Thrombosis

A new study has provided further reassurance on questions about the risk of intracerebral hemorrhage (ICH) with statins.

The Danish case-control study, which compared statin use in 2,164 case patients with ICH and in 86,255 matched control persons, found that current statin use was associated with a lower risk of having a first ICH and that the risk was further reduced with longer duration of statin use.

The study also showed that statin use was linked to a lower risk of ICH in the more superficial lobar areas of the brain and in the deeper, nonlobar locations. There was no difference in the magnitude of risk reduction between the two locations.

“Although this study is observational, I feel these data are strong, and the results are reassuring. It certainly does not suggest any increased risk of ICH with statins,” senior author David Gaist, PhD, Odense University Hospital, Denmark, said in an interview.

“On the contrary, it indicates a lower risk, which seems to be independent of the location of the bleed.”

The study was published online in Neurology.

The authors note that statins effectively reduce the occurrence of cardiovascular events and ischemic stroke in high-risk populations, but early randomized trials raised concerns of an increased risk of ICH among statin users who have a history of stroke.

Subsequent observational studies, including four meta-analyses, included patients with and those without prior stroke. The results were inconsistent, although most found no increase in bleeding. More recent studies have found a lower risk of ICH among statin users; the risk was inversely associated with the duration and intensity of statin treatment.

However, the researchers point out that few studies have assessed the association between statin use and the location of ICH. Hemorrhages that occur in the lobar region of the brain and those that occur in the nonlobar areas can have different pathophysiologies. Arteriolosclerosis, which is strongly associated with hypertension, is a common histologic finding in patients with ICH, regardless of hemorrhage location, while cerebral amyloid angiopathy (CAA) is associated with lobar but not nonlobar ICH.

The current study was conducted to look more closely at the relationship between statin use and hematoma location as a reflection of differences in the underlying pathophysiologies of lobar versus nonlobar ICH.

The researchers used Danish registries to identify all first-ever cases of spontaneous ICH that occurred between 2009 and 2018 in persons older than 55 years in the Southern Denmark region. Patients with traumatic ICH or ICH related to vascular malformations and tumors were excluded.

These cases were verified through medical records. ICH diagnoses were classified as having a lobar or nonlobar location, and patients were matched for age, sex, and calendar year to general population control persons. The nationwide prescription registry was also analyzed to ascertain use of statins and other medications.

The study included 989 patients with lobar ICH who were matched to 39,500 control persons and 1,175 patients with nonlobar ICH who were matched to 46,755 control persons.

Results showed that current statin use was associated with a 16%-17% relative reduction in ICH risk. There was no difference with respect to ICH location.

For lobar ICH, statin use showed an adjusted odds ratio of 0.83 (95% confidence interval, 0.70-0.98); for nonlobar ICH, the adjusted odds ratio was 0.84 (95% CI, 0.72-0.98).

Longer duration of statin use was associated with a greater reduction in risk of ICH; use for more than 5 years was associated with a relative reduction of ICH of 33%-38%, again with no difference with regard to ICH location.

For lobar ICH, statin use for more than 5 years showed an adjusted odds ratio of 0.67 (95% CI, 0.51-0.87); and for nonlobar ICH, the adjusted odds ratio was 0.62 (95% CI, 0.48-0.80).

“We suspected that statins may have more of an effect in reducing nonlobar ICH, as this type is considered to be more associated with arteriosclerosis, compared with lobar ICH,” Dr. Gaist explained. “But we didn’t find that. We found that taking statins was associated with a similar reduction in risk of both lobar and nonlobar ICH.”

Although amyloid angiopathy can contribute to lobar ICH, arteriosclerosis is still involved in the majority of cases, he noted. He cited a recent population-based U.K. study that showed that while histologically verified CAA was present in 58% of patients with a lobar ICH, most also had evidence of arteriosclerosis, with only 13% having isolated CAA pathology.

“If statins exert their effect on reducing ICH by reducing arteriosclerosis, which is likely, then this observation of arteriosclerosis pathology being prevalent in both lobar and nonlobar ICH locations would explain our results,” Dr. Gaist commented.

“Strengths of our study include the large numbers involved and the fact that the patients are unselected. We tried to find everyone who had had a first ICH in a well-defined region of Denmark, so issues of selection are less of a concern than in some other studies,” he noted.

He also pointed out that all the ICH diagnoses were verified from medical records and that in a substudy, brain scans were evaluated, with investigators masked to clinical data to evaluate the location and characteristics of the hematoma. In addition, data on statin use were collected prospectively from a nationwide prescription registry.
 

Interaction with antihypertensives, anticoagulants?

Other results from the study suggest a possible interaction between statin use and antihypertensive and anticoagulant drugs.

Data showed that the lower ICH risk was restricted to patients who received statins and antihypertensive drugs concurrently. Conversely, only patients who were not concurrently taking anticoagulants had a lower risk of ICH in association with statin use.

Dr. Gaist suggested that the lack of a reduction in ICH with statins among patients taking anticoagulants could be because the increased risk of ICH with anticoagulants was stronger than the reduced risk with statins.

Regarding the fact that the reduced risk of ICH with statins was only observed among individuals who were also taking antihypertensive medication, Dr. Gaist noted that because hypertension is such an important risk factor for ICH, “it may be that to get the true benefit of statins, patients have to have their hypertension controlled.”

However, an alternative explanation could that the finding is a result of “healthy adherer” bias, in which people who take antihypertensive medication and follow a healthy lifestyle as advised would be more likely to take statins.

“The observational nature of our study does not allow us to determine the extent to which associations are causal,” the authors say.

Dr. Gaist also noted that an important caveat in this study is that they focused on individuals who had had a first ICH.

“This data does not inform us about those who have already had an ICH and are taking statins. But we are planning to look at this in our next study,” he said.

The study was funded by the Novo Nordisk Foundation. Dr. Gaist has received speaker honorarium from Bristol-Myers Squibb and Pfizer unrelated to this work.

A version of this article first appeared on Medscape.com.

A new study has provided further reassurance on questions about the risk of intracerebral hemorrhage (ICH) with statins.

The Danish case-control study, which compared statin use in 2,164 case patients with ICH and in 86,255 matched control persons, found that current statin use was associated with a lower risk of having a first ICH and that the risk was further reduced with longer duration of statin use.

The study also showed that statin use was linked to a lower risk of ICH in the more superficial lobar areas of the brain and in the deeper, nonlobar locations. There was no difference in the magnitude of risk reduction between the two locations.

“Although this study is observational, I feel these data are strong, and the results are reassuring. It certainly does not suggest any increased risk of ICH with statins,” senior author David Gaist, PhD, Odense University Hospital, Denmark, said in an interview.

“On the contrary, it indicates a lower risk, which seems to be independent of the location of the bleed.”

The study was published online in Neurology.

The authors note that statins effectively reduce the occurrence of cardiovascular events and ischemic stroke in high-risk populations, but early randomized trials raised concerns of an increased risk of ICH among statin users who have a history of stroke.

Subsequent observational studies, including four meta-analyses, included patients with and those without prior stroke. The results were inconsistent, although most found no increase in bleeding. More recent studies have found a lower risk of ICH among statin users; the risk was inversely associated with the duration and intensity of statin treatment.

However, the researchers point out that few studies have assessed the association between statin use and the location of ICH. Hemorrhages that occur in the lobar region of the brain and those that occur in the nonlobar areas can have different pathophysiologies. Arteriolosclerosis, which is strongly associated with hypertension, is a common histologic finding in patients with ICH, regardless of hemorrhage location, while cerebral amyloid angiopathy (CAA) is associated with lobar but not nonlobar ICH.

The current study was conducted to look more closely at the relationship between statin use and hematoma location as a reflection of differences in the underlying pathophysiologies of lobar versus nonlobar ICH.

The researchers used Danish registries to identify all first-ever cases of spontaneous ICH that occurred between 2009 and 2018 in persons older than 55 years in the Southern Denmark region. Patients with traumatic ICH or ICH related to vascular malformations and tumors were excluded.

These cases were verified through medical records. ICH diagnoses were classified as having a lobar or nonlobar location, and patients were matched for age, sex, and calendar year to general population control persons. The nationwide prescription registry was also analyzed to ascertain use of statins and other medications.

The study included 989 patients with lobar ICH who were matched to 39,500 control persons and 1,175 patients with nonlobar ICH who were matched to 46,755 control persons.

Results showed that current statin use was associated with a 16%-17% relative reduction in ICH risk. There was no difference with respect to ICH location.

For lobar ICH, statin use showed an adjusted odds ratio of 0.83 (95% confidence interval, 0.70-0.98); for nonlobar ICH, the adjusted odds ratio was 0.84 (95% CI, 0.72-0.98).

Longer duration of statin use was associated with a greater reduction in risk of ICH; use for more than 5 years was associated with a relative reduction of ICH of 33%-38%, again with no difference with regard to ICH location.

For lobar ICH, statin use for more than 5 years showed an adjusted odds ratio of 0.67 (95% CI, 0.51-0.87); and for nonlobar ICH, the adjusted odds ratio was 0.62 (95% CI, 0.48-0.80).

“We suspected that statins may have more of an effect in reducing nonlobar ICH, as this type is considered to be more associated with arteriosclerosis, compared with lobar ICH,” Dr. Gaist explained. “But we didn’t find that. We found that taking statins was associated with a similar reduction in risk of both lobar and nonlobar ICH.”

Although amyloid angiopathy can contribute to lobar ICH, arteriosclerosis is still involved in the majority of cases, he noted. He cited a recent population-based U.K. study that showed that while histologically verified CAA was present in 58% of patients with a lobar ICH, most also had evidence of arteriosclerosis, with only 13% having isolated CAA pathology.

“If statins exert their effect on reducing ICH by reducing arteriosclerosis, which is likely, then this observation of arteriosclerosis pathology being prevalent in both lobar and nonlobar ICH locations would explain our results,” Dr. Gaist commented.

“Strengths of our study include the large numbers involved and the fact that the patients are unselected. We tried to find everyone who had had a first ICH in a well-defined region of Denmark, so issues of selection are less of a concern than in some other studies,” he noted.

He also pointed out that all the ICH diagnoses were verified from medical records and that in a substudy, brain scans were evaluated, with investigators masked to clinical data to evaluate the location and characteristics of the hematoma. In addition, data on statin use were collected prospectively from a nationwide prescription registry.
 

Interaction with antihypertensives, anticoagulants?

Other results from the study suggest a possible interaction between statin use and antihypertensive and anticoagulant drugs.

Data showed that the lower ICH risk was restricted to patients who received statins and antihypertensive drugs concurrently. Conversely, only patients who were not concurrently taking anticoagulants had a lower risk of ICH in association with statin use.

Dr. Gaist suggested that the lack of a reduction in ICH with statins among patients taking anticoagulants could be because the increased risk of ICH with anticoagulants was stronger than the reduced risk with statins.

Regarding the fact that the reduced risk of ICH with statins was only observed among individuals who were also taking antihypertensive medication, Dr. Gaist noted that because hypertension is such an important risk factor for ICH, “it may be that to get the true benefit of statins, patients have to have their hypertension controlled.”

However, an alternative explanation could that the finding is a result of “healthy adherer” bias, in which people who take antihypertensive medication and follow a healthy lifestyle as advised would be more likely to take statins.

“The observational nature of our study does not allow us to determine the extent to which associations are causal,” the authors say.

Dr. Gaist also noted that an important caveat in this study is that they focused on individuals who had had a first ICH.

“This data does not inform us about those who have already had an ICH and are taking statins. But we are planning to look at this in our next study,” he said.

The study was funded by the Novo Nordisk Foundation. Dr. Gaist has received speaker honorarium from Bristol-Myers Squibb and Pfizer unrelated to this work.

A version of this article first appeared on Medscape.com.

A new study has provided further reassurance on questions about the risk of intracerebral hemorrhage (ICH) with statins.

The Danish case-control study, which compared statin use in 2,164 case patients with ICH and in 86,255 matched control persons, found that current statin use was associated with a lower risk of having a first ICH and that the risk was further reduced with longer duration of statin use.

The study also showed that statin use was linked to a lower risk of ICH in the more superficial lobar areas of the brain and in the deeper, nonlobar locations. There was no difference in the magnitude of risk reduction between the two locations.

“Although this study is observational, I feel these data are strong, and the results are reassuring. It certainly does not suggest any increased risk of ICH with statins,” senior author David Gaist, PhD, Odense University Hospital, Denmark, said in an interview.

“On the contrary, it indicates a lower risk, which seems to be independent of the location of the bleed.”

The study was published online in Neurology.

The authors note that statins effectively reduce the occurrence of cardiovascular events and ischemic stroke in high-risk populations, but early randomized trials raised concerns of an increased risk of ICH among statin users who have a history of stroke.

Subsequent observational studies, including four meta-analyses, included patients with and those without prior stroke. The results were inconsistent, although most found no increase in bleeding. More recent studies have found a lower risk of ICH among statin users; the risk was inversely associated with the duration and intensity of statin treatment.

However, the researchers point out that few studies have assessed the association between statin use and the location of ICH. Hemorrhages that occur in the lobar region of the brain and those that occur in the nonlobar areas can have different pathophysiologies. Arteriolosclerosis, which is strongly associated with hypertension, is a common histologic finding in patients with ICH, regardless of hemorrhage location, while cerebral amyloid angiopathy (CAA) is associated with lobar but not nonlobar ICH.

The current study was conducted to look more closely at the relationship between statin use and hematoma location as a reflection of differences in the underlying pathophysiologies of lobar versus nonlobar ICH.

The researchers used Danish registries to identify all first-ever cases of spontaneous ICH that occurred between 2009 and 2018 in persons older than 55 years in the Southern Denmark region. Patients with traumatic ICH or ICH related to vascular malformations and tumors were excluded.

These cases were verified through medical records. ICH diagnoses were classified as having a lobar or nonlobar location, and patients were matched for age, sex, and calendar year to general population control persons. The nationwide prescription registry was also analyzed to ascertain use of statins and other medications.

The study included 989 patients with lobar ICH who were matched to 39,500 control persons and 1,175 patients with nonlobar ICH who were matched to 46,755 control persons.

Results showed that current statin use was associated with a 16%-17% relative reduction in ICH risk. There was no difference with respect to ICH location.

For lobar ICH, statin use showed an adjusted odds ratio of 0.83 (95% confidence interval, 0.70-0.98); for nonlobar ICH, the adjusted odds ratio was 0.84 (95% CI, 0.72-0.98).

Longer duration of statin use was associated with a greater reduction in risk of ICH; use for more than 5 years was associated with a relative reduction of ICH of 33%-38%, again with no difference with regard to ICH location.

For lobar ICH, statin use for more than 5 years showed an adjusted odds ratio of 0.67 (95% CI, 0.51-0.87); and for nonlobar ICH, the adjusted odds ratio was 0.62 (95% CI, 0.48-0.80).

“We suspected that statins may have more of an effect in reducing nonlobar ICH, as this type is considered to be more associated with arteriosclerosis, compared with lobar ICH,” Dr. Gaist explained. “But we didn’t find that. We found that taking statins was associated with a similar reduction in risk of both lobar and nonlobar ICH.”

Although amyloid angiopathy can contribute to lobar ICH, arteriosclerosis is still involved in the majority of cases, he noted. He cited a recent population-based U.K. study that showed that while histologically verified CAA was present in 58% of patients with a lobar ICH, most also had evidence of arteriosclerosis, with only 13% having isolated CAA pathology.

“If statins exert their effect on reducing ICH by reducing arteriosclerosis, which is likely, then this observation of arteriosclerosis pathology being prevalent in both lobar and nonlobar ICH locations would explain our results,” Dr. Gaist commented.

“Strengths of our study include the large numbers involved and the fact that the patients are unselected. We tried to find everyone who had had a first ICH in a well-defined region of Denmark, so issues of selection are less of a concern than in some other studies,” he noted.

He also pointed out that all the ICH diagnoses were verified from medical records and that in a substudy, brain scans were evaluated, with investigators masked to clinical data to evaluate the location and characteristics of the hematoma. In addition, data on statin use were collected prospectively from a nationwide prescription registry.
 

Interaction with antihypertensives, anticoagulants?

Other results from the study suggest a possible interaction between statin use and antihypertensive and anticoagulant drugs.

Data showed that the lower ICH risk was restricted to patients who received statins and antihypertensive drugs concurrently. Conversely, only patients who were not concurrently taking anticoagulants had a lower risk of ICH in association with statin use.

Dr. Gaist suggested that the lack of a reduction in ICH with statins among patients taking anticoagulants could be because the increased risk of ICH with anticoagulants was stronger than the reduced risk with statins.

Regarding the fact that the reduced risk of ICH with statins was only observed among individuals who were also taking antihypertensive medication, Dr. Gaist noted that because hypertension is such an important risk factor for ICH, “it may be that to get the true benefit of statins, patients have to have their hypertension controlled.”

However, an alternative explanation could that the finding is a result of “healthy adherer” bias, in which people who take antihypertensive medication and follow a healthy lifestyle as advised would be more likely to take statins.

“The observational nature of our study does not allow us to determine the extent to which associations are causal,” the authors say.

Dr. Gaist also noted that an important caveat in this study is that they focused on individuals who had had a first ICH.

“This data does not inform us about those who have already had an ICH and are taking statins. But we are planning to look at this in our next study,” he said.

The study was funded by the Novo Nordisk Foundation. Dr. Gaist has received speaker honorarium from Bristol-Myers Squibb and Pfizer unrelated to this work.

A version of this article first appeared on Medscape.com.

NEW ORLEANS – In yet another indication of health disparities facing ethnic minorities, new research found that non-White patients with pulmonary embolism (PE) were less likely to get advanced therapies. Hispanics and Asians/Pacific Islanders, meanwhile, had higher death rates than Whites.

According to the research, released at the annual meeting of the American Society of Hematology, the biggest disparities affected Asian/Pacific Islander patients with PE. While they were the least likely among ethnic groups to be hospitalized for PE, the odds were 53% higher that they’d die in the hospital (adjusted odds ratio, 1.53; 95% confidence interval, 1.32-1.78), and 24% lower that they would get advanced therapies (aOR, 0.76; 95% CI, 0.59-0.98, P values not provided in this study).

“The findings really raise the importance of this research area and call for vigorous future research to try to better identify why we see these patterns and then come up with solutions to solve them,” said hematologist and study coauthor Mary Cushman, MD, of the University of Vermont, Burlington, at an ASH news briefing.

As Dr. Cushman noted, details about disparities in PE care are limited. It’s known that “Black people have a twofold greater mortality from pulmonary embolism compared to other groups, and this is a persistently observed disparity over many years,” she said. However, “little is known about the relationships of social determinants with treatment and course of pulmonary embolism,” she added.

The researchers used data from the Nationwide Inpatient Sample to track 1.1 million U.S. hospitalized patients with PE from 2016 to 2018. PE was the primary diagnosis in 615,570 patients (54.8%), and 66,570 (5.9%) had high-risk PE.

Among ethnic groups, hospitalization rates “differed pretty dramatically,” Dr. Cushman said. The researchers found that Blacks had the highest rate of PE hospitalization (20.1 per 10,000 person-years; 95% CI, 20.0-20.2), followed by Whites (13.1 per 10,000 person-years; 95% CI, 13.1-13.2), Hispanics (6.0 per 10,000 person-years; 95% CI, 5.9-6.1), Native Americans (5.6 per 10,000 person-years, 95% CI, 5.4-5.7) and Asians/Pacific Islanders (3.0 per 10,000 person-years; 95% CI, 2.9-3.1). Overall, the rate was 14.9/10,000 person-years.

With regard to treatment, therapies defined by the researchers as advanced – systemic thrombolysis, catheter-directed therapy, surgical embolectomy, and venoarterial extracorporeal membrane oxygenation – were also less commonly used in treating ethnic minorities.

These treatments were used in 5.5% of all patients, and 19% of those with high-risk PE. After adjusting for nearly 20 factors such as age, sex, and place of residence, researchers found that the odds that a patient would receive advanced treatment were lower in Blacks (aOR, 0.87; 95% CI, 0.81-0.92) and Asians/Pacific Islanders (aOR, 0.76; 95% CI, 0.59-0.98) compared with Whites. The differences in Hispanics and Native Americans were not statistically significant.

As for insurance, those with Medicare and Medicaid were less likely to get advanced treatment vs. those with private insurance (aOR, 0.73; 95% CI, 0.69-0.77 and aOR, 0.68; 95% CI, 0.63-0.74, respectively). Differences among income levels were not statistically significant.

In the hospital, 6.4% of patients with PE died, as did 50% of those with high-risk PE. There was no statistically significant difference in death rates overall between Whites and Blacks or Native Americans. However, Asians/Pacific Islanders had a much higher death rate (aOR, 1.53; 95% CI, 1.32-1.78), as did Hispanics (aOR, 1.10; 95% CI, 1.00-1.22).

Why are Asians/Pacific Islanders at such high risk of death? Dr. Cushman noted that, while their hospitalization rate is low, they are especially likely to present with high-risk PE.

The difference in death rates between patients with Medicare/Medicaid insurance and those with private insurance was not statistically significant. Neither was the difference in death rates among income groups vs. the highest quartile with one exception: The lowest quartile (aOR, 1.09; 95% CI, 1.02-1.17).

As for the reasons for the higher risks among various groups, Dr. Cushman said there are several possible theories. “It could be due to differences in awareness of PE symptoms: They don’t know how ill they are, so they present later in the course. Or they might have less trust in the system, which might lead to delayed care. Or it could be that they have misdiagnosis of PE symptoms when they present initially.”

Alternatively, she noted, the differences “could be rooted in structural racism and other social determinants of health that weren’t measured, such as education level and quality of education.”

In an interview, Dr. Cushman expressed the hope that “clinicians will think about these findings in terms of how they take care of patients and try their best to recognize any unconscious biases that might creep into their approach. In addition, as a society we need more education of the general public about PE. Some of our findings might be caused by delayed care due to lack of recognition of a need to seek care.”

In an interview, University of Pittsburgh vascular surgeon Rabih Chaer, MD, MSc, who didn’t take part in the study, said it relies on a "large dataset which offers valuable information but with limited granularity and follow-up. This limits the accurate categorization of PE severity, as well as comorbidities, all of which impact outcomes and survival.”

For example, Dr. Chaer said, PE treatments can be limited in some patients due to their comorbidities that cause bleeding risk. Still, Dr. Chaer said the findings mesh with his own research that has shown racial disparities in PE treatment and outcomes, including a 2021 study. "While we did not see a difference by race in in-hospital mortality, Black patients hospitalized with PE are younger with a higher severity of disease compared with White patients,” he said. "Although Black patients are less likely to receive an intervention overall, this differed depending on PE severity with higher risk of intervention only for life-threatening PE." And a 2022 study found that “patients with PE from deprived neighborhoods have worse survival beyond the index [first] admission and were more likely to suffer from cardiovascular or PE-related causes of death in the first year after the index pulmonary embolism,” he said. 

Dr. Chaer noted that his research team “is actively working on the next steps beyond identifying the fact that there are racial disparities in PE treatment and outcomes. We are fortunate to have access to a large granular database with long-term follow up and are currently reviewing the medical record details to identify causes for disparities and potential solutions.”

Dr. Cushman received funding from the National Institutes of Health. Other study authors report various disclosures. Dr. Chaer has no disclosures.

NEW ORLEANS – In yet another indication of health disparities facing ethnic minorities, new research found that non-White patients with pulmonary embolism (PE) were less likely to get advanced therapies. Hispanics and Asians/Pacific Islanders, meanwhile, had higher death rates than Whites.

According to the research, released at the annual meeting of the American Society of Hematology, the biggest disparities affected Asian/Pacific Islander patients with PE. While they were the least likely among ethnic groups to be hospitalized for PE, the odds were 53% higher that they’d die in the hospital (adjusted odds ratio, 1.53; 95% confidence interval, 1.32-1.78), and 24% lower that they would get advanced therapies (aOR, 0.76; 95% CI, 0.59-0.98, P values not provided in this study).

“The findings really raise the importance of this research area and call for vigorous future research to try to better identify why we see these patterns and then come up with solutions to solve them,” said hematologist and study coauthor Mary Cushman, MD, of the University of Vermont, Burlington, at an ASH news briefing.

As Dr. Cushman noted, details about disparities in PE care are limited. It’s known that “Black people have a twofold greater mortality from pulmonary embolism compared to other groups, and this is a persistently observed disparity over many years,” she said. However, “little is known about the relationships of social determinants with treatment and course of pulmonary embolism,” she added.

The researchers used data from the Nationwide Inpatient Sample to track 1.1 million U.S. hospitalized patients with PE from 2016 to 2018. PE was the primary diagnosis in 615,570 patients (54.8%), and 66,570 (5.9%) had high-risk PE.

Among ethnic groups, hospitalization rates “differed pretty dramatically,” Dr. Cushman said. The researchers found that Blacks had the highest rate of PE hospitalization (20.1 per 10,000 person-years; 95% CI, 20.0-20.2), followed by Whites (13.1 per 10,000 person-years; 95% CI, 13.1-13.2), Hispanics (6.0 per 10,000 person-years; 95% CI, 5.9-6.1), Native Americans (5.6 per 10,000 person-years, 95% CI, 5.4-5.7) and Asians/Pacific Islanders (3.0 per 10,000 person-years; 95% CI, 2.9-3.1). Overall, the rate was 14.9/10,000 person-years.

With regard to treatment, therapies defined by the researchers as advanced – systemic thrombolysis, catheter-directed therapy, surgical embolectomy, and venoarterial extracorporeal membrane oxygenation – were also less commonly used in treating ethnic minorities.

These treatments were used in 5.5% of all patients, and 19% of those with high-risk PE. After adjusting for nearly 20 factors such as age, sex, and place of residence, researchers found that the odds that a patient would receive advanced treatment were lower in Blacks (aOR, 0.87; 95% CI, 0.81-0.92) and Asians/Pacific Islanders (aOR, 0.76; 95% CI, 0.59-0.98) compared with Whites. The differences in Hispanics and Native Americans were not statistically significant.

As for insurance, those with Medicare and Medicaid were less likely to get advanced treatment vs. those with private insurance (aOR, 0.73; 95% CI, 0.69-0.77 and aOR, 0.68; 95% CI, 0.63-0.74, respectively). Differences among income levels were not statistically significant.

In the hospital, 6.4% of patients with PE died, as did 50% of those with high-risk PE. There was no statistically significant difference in death rates overall between Whites and Blacks or Native Americans. However, Asians/Pacific Islanders had a much higher death rate (aOR, 1.53; 95% CI, 1.32-1.78), as did Hispanics (aOR, 1.10; 95% CI, 1.00-1.22).

Why are Asians/Pacific Islanders at such high risk of death? Dr. Cushman noted that, while their hospitalization rate is low, they are especially likely to present with high-risk PE.

The difference in death rates between patients with Medicare/Medicaid insurance and those with private insurance was not statistically significant. Neither was the difference in death rates among income groups vs. the highest quartile with one exception: The lowest quartile (aOR, 1.09; 95% CI, 1.02-1.17).

As for the reasons for the higher risks among various groups, Dr. Cushman said there are several possible theories. “It could be due to differences in awareness of PE symptoms: They don’t know how ill they are, so they present later in the course. Or they might have less trust in the system, which might lead to delayed care. Or it could be that they have misdiagnosis of PE symptoms when they present initially.”

Alternatively, she noted, the differences “could be rooted in structural racism and other social determinants of health that weren’t measured, such as education level and quality of education.”

In an interview, Dr. Cushman expressed the hope that “clinicians will think about these findings in terms of how they take care of patients and try their best to recognize any unconscious biases that might creep into their approach. In addition, as a society we need more education of the general public about PE. Some of our findings might be caused by delayed care due to lack of recognition of a need to seek care.”

In an interview, University of Pittsburgh vascular surgeon Rabih Chaer, MD, MSc, who didn’t take part in the study, said it relies on a "large dataset which offers valuable information but with limited granularity and follow-up. This limits the accurate categorization of PE severity, as well as comorbidities, all of which impact outcomes and survival.”

For example, Dr. Chaer said, PE treatments can be limited in some patients due to their comorbidities that cause bleeding risk. Still, Dr. Chaer said the findings mesh with his own research that has shown racial disparities in PE treatment and outcomes, including a 2021 study. "While we did not see a difference by race in in-hospital mortality, Black patients hospitalized with PE are younger with a higher severity of disease compared with White patients,” he said. "Although Black patients are less likely to receive an intervention overall, this differed depending on PE severity with higher risk of intervention only for life-threatening PE." And a 2022 study found that “patients with PE from deprived neighborhoods have worse survival beyond the index [first] admission and were more likely to suffer from cardiovascular or PE-related causes of death in the first year after the index pulmonary embolism,” he said. 

Dr. Chaer noted that his research team “is actively working on the next steps beyond identifying the fact that there are racial disparities in PE treatment and outcomes. We are fortunate to have access to a large granular database with long-term follow up and are currently reviewing the medical record details to identify causes for disparities and potential solutions.”

Dr. Cushman received funding from the National Institutes of Health. Other study authors report various disclosures. Dr. Chaer has no disclosures.

NEW ORLEANS – In yet another indication of health disparities facing ethnic minorities, new research found that non-White patients with pulmonary embolism (PE) were less likely to get advanced therapies. Hispanics and Asians/Pacific Islanders, meanwhile, had higher death rates than Whites.

According to the research, released at the annual meeting of the American Society of Hematology, the biggest disparities affected Asian/Pacific Islander patients with PE. While they were the least likely among ethnic groups to be hospitalized for PE, the odds were 53% higher that they’d die in the hospital (adjusted odds ratio, 1.53; 95% confidence interval, 1.32-1.78), and 24% lower that they would get advanced therapies (aOR, 0.76; 95% CI, 0.59-0.98, P values not provided in this study).

“The findings really raise the importance of this research area and call for vigorous future research to try to better identify why we see these patterns and then come up with solutions to solve them,” said hematologist and study coauthor Mary Cushman, MD, of the University of Vermont, Burlington, at an ASH news briefing.

As Dr. Cushman noted, details about disparities in PE care are limited. It’s known that “Black people have a twofold greater mortality from pulmonary embolism compared to other groups, and this is a persistently observed disparity over many years,” she said. However, “little is known about the relationships of social determinants with treatment and course of pulmonary embolism,” she added.

The researchers used data from the Nationwide Inpatient Sample to track 1.1 million U.S. hospitalized patients with PE from 2016 to 2018. PE was the primary diagnosis in 615,570 patients (54.8%), and 66,570 (5.9%) had high-risk PE.

Among ethnic groups, hospitalization rates “differed pretty dramatically,” Dr. Cushman said. The researchers found that Blacks had the highest rate of PE hospitalization (20.1 per 10,000 person-years; 95% CI, 20.0-20.2), followed by Whites (13.1 per 10,000 person-years; 95% CI, 13.1-13.2), Hispanics (6.0 per 10,000 person-years; 95% CI, 5.9-6.1), Native Americans (5.6 per 10,000 person-years, 95% CI, 5.4-5.7) and Asians/Pacific Islanders (3.0 per 10,000 person-years; 95% CI, 2.9-3.1). Overall, the rate was 14.9/10,000 person-years.

With regard to treatment, therapies defined by the researchers as advanced – systemic thrombolysis, catheter-directed therapy, surgical embolectomy, and venoarterial extracorporeal membrane oxygenation – were also less commonly used in treating ethnic minorities.

These treatments were used in 5.5% of all patients, and 19% of those with high-risk PE. After adjusting for nearly 20 factors such as age, sex, and place of residence, researchers found that the odds that a patient would receive advanced treatment were lower in Blacks (aOR, 0.87; 95% CI, 0.81-0.92) and Asians/Pacific Islanders (aOR, 0.76; 95% CI, 0.59-0.98) compared with Whites. The differences in Hispanics and Native Americans were not statistically significant.

As for insurance, those with Medicare and Medicaid were less likely to get advanced treatment vs. those with private insurance (aOR, 0.73; 95% CI, 0.69-0.77 and aOR, 0.68; 95% CI, 0.63-0.74, respectively). Differences among income levels were not statistically significant.

In the hospital, 6.4% of patients with PE died, as did 50% of those with high-risk PE. There was no statistically significant difference in death rates overall between Whites and Blacks or Native Americans. However, Asians/Pacific Islanders had a much higher death rate (aOR, 1.53; 95% CI, 1.32-1.78), as did Hispanics (aOR, 1.10; 95% CI, 1.00-1.22).

Why are Asians/Pacific Islanders at such high risk of death? Dr. Cushman noted that, while their hospitalization rate is low, they are especially likely to present with high-risk PE.

The difference in death rates between patients with Medicare/Medicaid insurance and those with private insurance was not statistically significant. Neither was the difference in death rates among income groups vs. the highest quartile with one exception: The lowest quartile (aOR, 1.09; 95% CI, 1.02-1.17).

As for the reasons for the higher risks among various groups, Dr. Cushman said there are several possible theories. “It could be due to differences in awareness of PE symptoms: They don’t know how ill they are, so they present later in the course. Or they might have less trust in the system, which might lead to delayed care. Or it could be that they have misdiagnosis of PE symptoms when they present initially.”

Alternatively, she noted, the differences “could be rooted in structural racism and other social determinants of health that weren’t measured, such as education level and quality of education.”

In an interview, Dr. Cushman expressed the hope that “clinicians will think about these findings in terms of how they take care of patients and try their best to recognize any unconscious biases that might creep into their approach. In addition, as a society we need more education of the general public about PE. Some of our findings might be caused by delayed care due to lack of recognition of a need to seek care.”

In an interview, University of Pittsburgh vascular surgeon Rabih Chaer, MD, MSc, who didn’t take part in the study, said it relies on a "large dataset which offers valuable information but with limited granularity and follow-up. This limits the accurate categorization of PE severity, as well as comorbidities, all of which impact outcomes and survival.”

For example, Dr. Chaer said, PE treatments can be limited in some patients due to their comorbidities that cause bleeding risk. Still, Dr. Chaer said the findings mesh with his own research that has shown racial disparities in PE treatment and outcomes, including a 2021 study. "While we did not see a difference by race in in-hospital mortality, Black patients hospitalized with PE are younger with a higher severity of disease compared with White patients,” he said. "Although Black patients are less likely to receive an intervention overall, this differed depending on PE severity with higher risk of intervention only for life-threatening PE." And a 2022 study found that “patients with PE from deprived neighborhoods have worse survival beyond the index [first] admission and were more likely to suffer from cardiovascular or PE-related causes of death in the first year after the index pulmonary embolism,” he said. 

Dr. Chaer noted that his research team “is actively working on the next steps beyond identifying the fact that there are racial disparities in PE treatment and outcomes. We are fortunate to have access to a large granular database with long-term follow up and are currently reviewing the medical record details to identify causes for disparities and potential solutions.”

Dr. Cushman received funding from the National Institutes of Health. Other study authors report various disclosures. Dr. Chaer has no disclosures.

A new U.S. randomized trial has failed to show benefit of a 35-day course of oral anticoagulation with rivaroxaban for the prevention of thrombotic events in outpatients with symptomatic COVID-19.

The PREVENT-HD trial was presented at the American Heart Association scientific sessions by Gregory Piazza, MD, Brigham and Women’s Hospital, Boston.

“With the caveat that the trial was underpowered to provide a definitive conclusion, these data do not support routine antithrombotic prophylaxis in nonhospitalized patients with symptomatic COVID-19,” Dr. Piazza concluded.

PREVENT-HD is the largest randomized study to look at anticoagulation in nonhospitalized COVID-19 patients and joins a long list of smaller trials that have also shown no benefit with this approach.

However, anticoagulation is recommended in patients who are hospitalized with COVID-19.

Dr. Piazza noted that the issue of anticoagulation in COVID-19 has focused mainly on hospitalized patients, but most COVID-19 cases are treated as outpatients, who are also suspected to be at risk for venous and arterial thrombotic events, especially if they have additional risk factors. Histopathological evidence also suggests that at least part of the deterioration in lung function leading to hospitalization may be attributable to in situ pulmonary artery thrombosis.

The PREVENT-HD trial explored the question of whether early initiation of thromboprophylaxis dosing of rivaroxaban in higher-risk outpatients with COVID-19 may lower the incidence of venous and arterial thrombotic events, reduce in situ pulmonary thrombosis and the worsening of pulmonary function that may lead to hospitalization, and reduce all-cause mortality.

The trial included 1,284 outpatients with a positive test for COVID-19 and who were within 14 days of symptom onset. They also had to have at least one of the following additional risk factors: age over 60 years; prior history of venous thromboembolism (VTE), thrombophilia, coronary artery disease, peripheral artery disease, cardiovascular disease or ischemic stroke, cancer, diabetes, heart failure, obesity (body mass index ≥ 35 kg/m²) or D-dimer > upper limit of normal. Around 35% of the study population had two or more of these risk factors.

Patients were randomized to rivaroxaban 10 mg daily for 35 days or placebo.

The primary efficacy endpoint was time to first occurrence of a composite of symptomatic VTE, myocardial infarction, ischemic stroke, acute limb ischemia, non–central nervous system systemic embolization, all-cause hospitalization, and all-cause mortality up to day 35.

The primary safety endpoint was time to first occurrence of International Society on Thrombosis and Hemostasis (ISTH) critical-site and fatal bleeding.

A modified intention-to-treat analysis (all participants taking at least one dose of study intervention) was also planned.

The trial was stopped early in April this year because of a lower than expected event incidence (3.2%), compared with the planned rate (8.5%), giving a very low likelihood of being able to achieve the required number of events.

Dr. Piazza said reasons contributing to the low event rate included a falling COVID-19 death and hospitalization rate nationwide, and increased use of effective vaccines.

Results of the main intention-to-treat analysis (in 1,284 patients) showed no significant difference in the primary efficacy composite endpoint, which occurred in 3.4% of the rivaroxaban group versus 3.0% of the placebo group.

In the modified intention-to-treat analysis (which included 1,197 patients who actually took at least one dose of the study medication) there was shift in the directionality of the point estimate (rivaroxaban 2.0% vs. placebo 2.7%), which Dr. Piazza said was related to a higher number of patients hospitalized before receiving study drug in the rivaroxaban group. However, the difference was still nonsignificant. 

The first major secondary outcome of symptomatic VTE, arterial thrombotic events, and all-cause mortality occurred in 0.3% of rivaroxaban patients versus 1.1% of placebo patients, but this difference did not reach statistical significance.

However, a post hoc exploratory analysis did show a significant reduction in the outcome of symptomatic VTE and arterial thrombotic events. 

In terms of safety, there were no fatal critical-site bleeding events, and there was no difference in ISTH major bleeding, which occurred in one patient in the rivaroxaban group versus no patients in the placebo group.

There was, however, a significant increase in nonmajor clinically relevant bleeding with rivaroxaban, which occurred in nine patients (1.5%) versus one patient (0.2%) in the placebo group.

Trivial bleeding was also increased in the rivaroxaban group, occurring in 17 patients (2.8%) versus 5 patients (0.8%) in the placebo group.

Discussant for the study, Renato Lopes, MD, Duke University Medical Center, Durham, N.C., noted that the relationship between COVID-19 and thrombosis has been an important issue since the beginning of the pandemic, with many proposed mechanisms to explain the COVID-19–associated coagulopathy, which is a major cause of death and disability.

While observational data at the beginning of the pandemic suggested patients with COVID-19 might benefit from anticoagulation, looking at all the different randomized trials that have tested anticoagulation in COVID-19 outpatients, there is no treatment effect on the various different primary outcomes in those studies and also no effect on all-cause mortality, Dr. Lopes said. 

He pointed out that PREVENT-HD was stopped prematurely with only about one-third of the planned number of patients enrolled, “just like every other outpatient COVID-19 trial.”

He also drew attention to the low rates of vaccination in the trial population, which does not reflect the current vaccination rate in the United States, and said the different direction of the results between the main intention-to-treat and modified intention-to-treat analyses deserve further investigation.

However, Dr. Lopes concluded, “The results of this trial, in line with the body of evidence in this field, do not support the routine use of any antithrombotic therapy for outpatients with COVID-19.”

The PREVENT-HD trial was sponsored by Janssen. Dr. Piazza has reported receiving research support from Bristol-Myers Squibb/Pfizer Alliance, Bayer, Janssen, Alexion, Amgen, and Boston Scientific, and consulting fees from Bristol-Myers Squibb/Pfizer Alliance, Boston Scientific, Janssen, NAMSA, Prairie Education and Research Cooperative, Boston Clinical Research Institute, and Amgen.

A version of this article first appeared on Medscape.com.

A new U.S. randomized trial has failed to show benefit of a 35-day course of oral anticoagulation with rivaroxaban for the prevention of thrombotic events in outpatients with symptomatic COVID-19.

The PREVENT-HD trial was presented at the American Heart Association scientific sessions by Gregory Piazza, MD, Brigham and Women’s Hospital, Boston.

“With the caveat that the trial was underpowered to provide a definitive conclusion, these data do not support routine antithrombotic prophylaxis in nonhospitalized patients with symptomatic COVID-19,” Dr. Piazza concluded.

PREVENT-HD is the largest randomized study to look at anticoagulation in nonhospitalized COVID-19 patients and joins a long list of smaller trials that have also shown no benefit with this approach.

However, anticoagulation is recommended in patients who are hospitalized with COVID-19.

Dr. Piazza noted that the issue of anticoagulation in COVID-19 has focused mainly on hospitalized patients, but most COVID-19 cases are treated as outpatients, who are also suspected to be at risk for venous and arterial thrombotic events, especially if they have additional risk factors. Histopathological evidence also suggests that at least part of the deterioration in lung function leading to hospitalization may be attributable to in situ pulmonary artery thrombosis.

The PREVENT-HD trial explored the question of whether early initiation of thromboprophylaxis dosing of rivaroxaban in higher-risk outpatients with COVID-19 may lower the incidence of venous and arterial thrombotic events, reduce in situ pulmonary thrombosis and the worsening of pulmonary function that may lead to hospitalization, and reduce all-cause mortality.

The trial included 1,284 outpatients with a positive test for COVID-19 and who were within 14 days of symptom onset. They also had to have at least one of the following additional risk factors: age over 60 years; prior history of venous thromboembolism (VTE), thrombophilia, coronary artery disease, peripheral artery disease, cardiovascular disease or ischemic stroke, cancer, diabetes, heart failure, obesity (body mass index ≥ 35 kg/m²) or D-dimer > upper limit of normal. Around 35% of the study population had two or more of these risk factors.

Patients were randomized to rivaroxaban 10 mg daily for 35 days or placebo.

The primary efficacy endpoint was time to first occurrence of a composite of symptomatic VTE, myocardial infarction, ischemic stroke, acute limb ischemia, non–central nervous system systemic embolization, all-cause hospitalization, and all-cause mortality up to day 35.

The primary safety endpoint was time to first occurrence of International Society on Thrombosis and Hemostasis (ISTH) critical-site and fatal bleeding.

A modified intention-to-treat analysis (all participants taking at least one dose of study intervention) was also planned.

The trial was stopped early in April this year because of a lower than expected event incidence (3.2%), compared with the planned rate (8.5%), giving a very low likelihood of being able to achieve the required number of events.

Dr. Piazza said reasons contributing to the low event rate included a falling COVID-19 death and hospitalization rate nationwide, and increased use of effective vaccines.

Results of the main intention-to-treat analysis (in 1,284 patients) showed no significant difference in the primary efficacy composite endpoint, which occurred in 3.4% of the rivaroxaban group versus 3.0% of the placebo group.

In the modified intention-to-treat analysis (which included 1,197 patients who actually took at least one dose of the study medication) there was shift in the directionality of the point estimate (rivaroxaban 2.0% vs. placebo 2.7%), which Dr. Piazza said was related to a higher number of patients hospitalized before receiving study drug in the rivaroxaban group. However, the difference was still nonsignificant. 

The first major secondary outcome of symptomatic VTE, arterial thrombotic events, and all-cause mortality occurred in 0.3% of rivaroxaban patients versus 1.1% of placebo patients, but this difference did not reach statistical significance.

However, a post hoc exploratory analysis did show a significant reduction in the outcome of symptomatic VTE and arterial thrombotic events. 

In terms of safety, there were no fatal critical-site bleeding events, and there was no difference in ISTH major bleeding, which occurred in one patient in the rivaroxaban group versus no patients in the placebo group.

There was, however, a significant increase in nonmajor clinically relevant bleeding with rivaroxaban, which occurred in nine patients (1.5%) versus one patient (0.2%) in the placebo group.

Trivial bleeding was also increased in the rivaroxaban group, occurring in 17 patients (2.8%) versus 5 patients (0.8%) in the placebo group.

Discussant for the study, Renato Lopes, MD, Duke University Medical Center, Durham, N.C., noted that the relationship between COVID-19 and thrombosis has been an important issue since the beginning of the pandemic, with many proposed mechanisms to explain the COVID-19–associated coagulopathy, which is a major cause of death and disability.

While observational data at the beginning of the pandemic suggested patients with COVID-19 might benefit from anticoagulation, looking at all the different randomized trials that have tested anticoagulation in COVID-19 outpatients, there is no treatment effect on the various different primary outcomes in those studies and also no effect on all-cause mortality, Dr. Lopes said. 

He pointed out that PREVENT-HD was stopped prematurely with only about one-third of the planned number of patients enrolled, “just like every other outpatient COVID-19 trial.”

He also drew attention to the low rates of vaccination in the trial population, which does not reflect the current vaccination rate in the United States, and said the different direction of the results between the main intention-to-treat and modified intention-to-treat analyses deserve further investigation.

However, Dr. Lopes concluded, “The results of this trial, in line with the body of evidence in this field, do not support the routine use of any antithrombotic therapy for outpatients with COVID-19.”

The PREVENT-HD trial was sponsored by Janssen. Dr. Piazza has reported receiving research support from Bristol-Myers Squibb/Pfizer Alliance, Bayer, Janssen, Alexion, Amgen, and Boston Scientific, and consulting fees from Bristol-Myers Squibb/Pfizer Alliance, Boston Scientific, Janssen, NAMSA, Prairie Education and Research Cooperative, Boston Clinical Research Institute, and Amgen.

A version of this article first appeared on Medscape.com.

A new U.S. randomized trial has failed to show benefit of a 35-day course of oral anticoagulation with rivaroxaban for the prevention of thrombotic events in outpatients with symptomatic COVID-19.

The PREVENT-HD trial was presented at the American Heart Association scientific sessions by Gregory Piazza, MD, Brigham and Women’s Hospital, Boston.

“With the caveat that the trial was underpowered to provide a definitive conclusion, these data do not support routine antithrombotic prophylaxis in nonhospitalized patients with symptomatic COVID-19,” Dr. Piazza concluded.

PREVENT-HD is the largest randomized study to look at anticoagulation in nonhospitalized COVID-19 patients and joins a long list of smaller trials that have also shown no benefit with this approach.

However, anticoagulation is recommended in patients who are hospitalized with COVID-19.

Dr. Piazza noted that the issue of anticoagulation in COVID-19 has focused mainly on hospitalized patients, but most COVID-19 cases are treated as outpatients, who are also suspected to be at risk for venous and arterial thrombotic events, especially if they have additional risk factors. Histopathological evidence also suggests that at least part of the deterioration in lung function leading to hospitalization may be attributable to in situ pulmonary artery thrombosis.

The PREVENT-HD trial explored the question of whether early initiation of thromboprophylaxis dosing of rivaroxaban in higher-risk outpatients with COVID-19 may lower the incidence of venous and arterial thrombotic events, reduce in situ pulmonary thrombosis and the worsening of pulmonary function that may lead to hospitalization, and reduce all-cause mortality.

The trial included 1,284 outpatients with a positive test for COVID-19 and who were within 14 days of symptom onset. They also had to have at least one of the following additional risk factors: age over 60 years; prior history of venous thromboembolism (VTE), thrombophilia, coronary artery disease, peripheral artery disease, cardiovascular disease or ischemic stroke, cancer, diabetes, heart failure, obesity (body mass index ≥ 35 kg/m²) or D-dimer > upper limit of normal. Around 35% of the study population had two or more of these risk factors.

Patients were randomized to rivaroxaban 10 mg daily for 35 days or placebo.

The primary efficacy endpoint was time to first occurrence of a composite of symptomatic VTE, myocardial infarction, ischemic stroke, acute limb ischemia, non–central nervous system systemic embolization, all-cause hospitalization, and all-cause mortality up to day 35.

The primary safety endpoint was time to first occurrence of International Society on Thrombosis and Hemostasis (ISTH) critical-site and fatal bleeding.

A modified intention-to-treat analysis (all participants taking at least one dose of study intervention) was also planned.

The trial was stopped early in April this year because of a lower than expected event incidence (3.2%), compared with the planned rate (8.5%), giving a very low likelihood of being able to achieve the required number of events.

Dr. Piazza said reasons contributing to the low event rate included a falling COVID-19 death and hospitalization rate nationwide, and increased use of effective vaccines.

Results of the main intention-to-treat analysis (in 1,284 patients) showed no significant difference in the primary efficacy composite endpoint, which occurred in 3.4% of the rivaroxaban group versus 3.0% of the placebo group.

In the modified intention-to-treat analysis (which included 1,197 patients who actually took at least one dose of the study medication) there was shift in the directionality of the point estimate (rivaroxaban 2.0% vs. placebo 2.7%), which Dr. Piazza said was related to a higher number of patients hospitalized before receiving study drug in the rivaroxaban group. However, the difference was still nonsignificant. 

The first major secondary outcome of symptomatic VTE, arterial thrombotic events, and all-cause mortality occurred in 0.3% of rivaroxaban patients versus 1.1% of placebo patients, but this difference did not reach statistical significance.

However, a post hoc exploratory analysis did show a significant reduction in the outcome of symptomatic VTE and arterial thrombotic events. 

In terms of safety, there were no fatal critical-site bleeding events, and there was no difference in ISTH major bleeding, which occurred in one patient in the rivaroxaban group versus no patients in the placebo group.

There was, however, a significant increase in nonmajor clinically relevant bleeding with rivaroxaban, which occurred in nine patients (1.5%) versus one patient (0.2%) in the placebo group.

Trivial bleeding was also increased in the rivaroxaban group, occurring in 17 patients (2.8%) versus 5 patients (0.8%) in the placebo group.

Discussant for the study, Renato Lopes, MD, Duke University Medical Center, Durham, N.C., noted that the relationship between COVID-19 and thrombosis has been an important issue since the beginning of the pandemic, with many proposed mechanisms to explain the COVID-19–associated coagulopathy, which is a major cause of death and disability.

While observational data at the beginning of the pandemic suggested patients with COVID-19 might benefit from anticoagulation, looking at all the different randomized trials that have tested anticoagulation in COVID-19 outpatients, there is no treatment effect on the various different primary outcomes in those studies and also no effect on all-cause mortality, Dr. Lopes said. 

He pointed out that PREVENT-HD was stopped prematurely with only about one-third of the planned number of patients enrolled, “just like every other outpatient COVID-19 trial.”

He also drew attention to the low rates of vaccination in the trial population, which does not reflect the current vaccination rate in the United States, and said the different direction of the results between the main intention-to-treat and modified intention-to-treat analyses deserve further investigation.

However, Dr. Lopes concluded, “The results of this trial, in line with the body of evidence in this field, do not support the routine use of any antithrombotic therapy for outpatients with COVID-19.”

The PREVENT-HD trial was sponsored by Janssen. Dr. Piazza has reported receiving research support from Bristol-Myers Squibb/Pfizer Alliance, Bayer, Janssen, Alexion, Amgen, and Boston Scientific, and consulting fees from Bristol-Myers Squibb/Pfizer Alliance, Boston Scientific, Janssen, NAMSA, Prairie Education and Research Cooperative, Boston Clinical Research Institute, and Amgen.

A version of this article first appeared on Medscape.com.

CHICAGO – A clinical decision-support tool designed to identify hospitalized patients who need thromboembolism prophylaxis and embedded in a hospital’s electronic health record led to significantly more appropriate prophylaxis, compared with usual care, and significantly cut the 30-day rate of thromboembolism in a randomized, multicenter trial with more than 10,000 patients.

“This is the first time that a clinical decision support tool not only changed [thromboprophylaxis prescribing] behavior but also affected hard outcomes. That’s remarkable,” lead investigator Alex C. Spyropoulos, MD, said in an interview.

Even so, outside experts expressed concerns about certain results and the trial design.

Mitchel L. Zoler/MDedge News

Use of the decision-support risk calculator for thromboembolism in the IMPROVE-DD VTE trial significantly boosted use of appropriate inpatient thromboprophylaxis starting at hospital admission by a relative 52%, and significantly increased outpatient thromboprophylaxis prescribed at discharge by a relative 93% in the study’s two primary endpoints, Dr. Spyropoulos reported at the American Heart Association scientific sessions.

This intervention led to a significant 29% relative reduction in the incidence of total thromboembolic events, both venous and arterial, during hospitalization and through 30 days post discharge.

The absolute thromboembolic event rates were 2.9% among 5,249 patients treated at either of two U.S. hospitals that used the EHR-based risk calculator and 4.0% in 5,450 patients seen at either of two other U.S. hospitals that served as controls and where usual care method identified patients who needed thromboprophylaxis, said Dr. Spyropoulos, professor and director of the anticoagulation and clinical thrombosis services for Northwell Health in New York. This included a 2.7% rate of venous thromboembolism and a 0.25% rate of arterial thromboembolism in the intervention patients, and a 3.3% rate of venous events and a 0.7% rate of arterial events in the controls.

Patients treated at the hospitals that used the EHR-embedded risk calculator also has a numerically lower rate of major bleeding events during hospitalization and 30-day postdischarge follow-up, a 0.15% rate compared with a 0.22% rate in the control patients, a difference that was not significant.
 

A ‘powerful message’

“It’s a powerful message to see an absolute 1.1% difference in the rate of thromboembolism and a trend to fewer major bleeds. I think this will change practice,” Dr. Spyropoulos added in the interview. “The next step is dissemination.”

But thromboprophylaxis experts cautioned that, while the results looked promising, the findings need more analysis and review, and the intervention may need further testing before it’s ready for widespread use.

For example, one unexpected result was an unexpected 2.1 percentage point increase in all-cause mortality linked with use of the decision-support tool. Total deaths from admission to 30 days after discharge occurred in 9.1% of the patients treated at the two hospitals that used the risk calculator and 7.0% among the control patients, a difference that Dr, Spyropoulos said was likely the result of unbalanced outcomes from COVID-19 infections that had no relevance to the tested intervention. The trial ran during December 2020–January 2022.
 

But wait – more detail and analysis needed

“I’d like to see more analysis of the data from this trial,” and “there is the issue of increased mortality,” commented Gregory Piazza, MD, director of vascular medicine at Brigham and Women’s Hospital in Boston, and a specialist in thromboembolism prevention and management. He also highlighted the need for greater detail on the arterial thromboembolic events tallied during the study.

With more details and analysis of these findings “we’ll learn more about the true impact” of this intervention, Dr. Piazza said in an interview.

Mitchel L. Zoler/MDedge News

“The increased mortality in the intervention group may have been due to differential treatment and decision-making and confounding and warrants further investigation,” commented Elaine M. Hylek, MD, a professor at Boston University and designated discussant for the report. Selection bias may have contributed to this possible confounding, Dr. Hylek noted.

Other limitations of the study cited by Dr. Hylek included its reliance on individual clinician decision-making to actually prescribe thromboprophylaxis, a lack of information on patient adherence to their thromboprophylaxis prescription, and an overall low rate of appropriate thromboprophylaxis prescribed to patients at discharge. The rates were 7.5% among the controls and 13.6% among patients in the intervention arm. For prescription at the time of hospitalization, the rates were 72.5% among control patients and 80.1% for patients seen at the two hospitals that used the decision-support tool.
 

The IMPROVE-DD VTE risk assessment tool

The clinical decision-support tool tested is called the IMPROVE-DD VTE risk assessment model, developed over several years by Dr. Spyropoulos and associates; they have also performed multiple validation studies. The model includes eight factors that score 1-3 points if positive that can add up to total scores of 0-14. A score of 0 or 1 is considered low risk, 2 or 3 intermediate risk, and 4 or more high risk. One of the scoring factors is the result of a D-dimer test, which explains the DD part of the name.

The eight factors and point assignments are prior venous thromboembolism: 3 points; known thrombophilia: 2 points; lower limb paralysis: 2 points; current cancer: 2 points; d-dimer level more than twofold the upper limit of normal: 2 points; immobilized for at least 7 days: 1 point; admitted to the ICU or coronary care unit: 1 point; and age greater than 60 years old: 1 point.

Development of the IMPROVE-DD VTE risk calculator received most of its funding from the U.S. Agency for Healthcare Research and Quality, and the risk tool will be available for hospitals and health systems to access at no charge through the agency’s website, Dr. Spyropoulos said. The researchers designed the calculator to operate in any EHR product.

IMPROVE-DD VTE “is a very valid, high-quality tool,” commented Dr. Piazza. “We’ve used some rather blunt tools in the past,” and especially praised inclusion of D-dimer results into the IMPROVE-DD VTE model.

“It’s nice to use a biomarker in addition to clinical factors,” he said. “A biomarker provides a more holistic picture; we can’t do genetic testing on every patient.”

Enrollment focused on higher-risk patients

The study ran at four academic, tertiary-care hospitals in the Northwell Health network in the New York region. It enrolled patients aged more than 60 years who were hospitalized for any of five diagnoses: heart failure; acute respiratory insufficiency, including chronic obstructive lung disease or asthma; acute infectious disease, including COVID-19; acute inflammatory disease, including rheumatic disease; or acute stroke. The study excluded patients with a history of atrial fibrillation, those who used an anticoagulant at home, or those who had received therapeutic anticoagulation within 24 hours of their hospital admission.

The anticoagulant prophylaxis that patients received depended on their calculated risk level – intermediate or high – and whether they were inpatients or being discharged. The anticoagulants that clinicians could prescribe included unfractionated heparin, enoxaparin, fondaparinux, rivaroxaban, and apixaban.

“We’ve been looking for a long time for a tool for medically ill patients that’s like the CHA2DS2-VASc score” for patients with atrial fibrillation. “These powerful data say we now have this, and the EHR provides a vehicle to easily implement it,” Dr. Spyropoulos said.

The IMPROVE-DD VTE study received partial funding from Janssen. Dr. Spyropoulos has been a consultant to Nayer, Boehringer Ingelheim, Bristol-Myers Squibb, Janssen, Pfizer, and Sanofi; adviser to the ATLAS Group; and has received research support from Janssen. Dr. Piazza has received research funding from Bayer, BIG/EKOS, BMS, Janssen, and Portola. Dr. Hylek had been a consultant to Bayer and Ionis, and has received honoraria from Boehringer Ingelheim and Pfizer.

CHICAGO – A clinical decision-support tool designed to identify hospitalized patients who need thromboembolism prophylaxis and embedded in a hospital’s electronic health record led to significantly more appropriate prophylaxis, compared with usual care, and significantly cut the 30-day rate of thromboembolism in a randomized, multicenter trial with more than 10,000 patients.

“This is the first time that a clinical decision support tool not only changed [thromboprophylaxis prescribing] behavior but also affected hard outcomes. That’s remarkable,” lead investigator Alex C. Spyropoulos, MD, said in an interview.

Even so, outside experts expressed concerns about certain results and the trial design.

Mitchel L. Zoler/MDedge News

Use of the decision-support risk calculator for thromboembolism in the IMPROVE-DD VTE trial significantly boosted use of appropriate inpatient thromboprophylaxis starting at hospital admission by a relative 52%, and significantly increased outpatient thromboprophylaxis prescribed at discharge by a relative 93% in the study’s two primary endpoints, Dr. Spyropoulos reported at the American Heart Association scientific sessions.

This intervention led to a significant 29% relative reduction in the incidence of total thromboembolic events, both venous and arterial, during hospitalization and through 30 days post discharge.

The absolute thromboembolic event rates were 2.9% among 5,249 patients treated at either of two U.S. hospitals that used the EHR-based risk calculator and 4.0% in 5,450 patients seen at either of two other U.S. hospitals that served as controls and where usual care method identified patients who needed thromboprophylaxis, said Dr. Spyropoulos, professor and director of the anticoagulation and clinical thrombosis services for Northwell Health in New York. This included a 2.7% rate of venous thromboembolism and a 0.25% rate of arterial thromboembolism in the intervention patients, and a 3.3% rate of venous events and a 0.7% rate of arterial events in the controls.

Patients treated at the hospitals that used the EHR-embedded risk calculator also has a numerically lower rate of major bleeding events during hospitalization and 30-day postdischarge follow-up, a 0.15% rate compared with a 0.22% rate in the control patients, a difference that was not significant.
 

A ‘powerful message’

“It’s a powerful message to see an absolute 1.1% difference in the rate of thromboembolism and a trend to fewer major bleeds. I think this will change practice,” Dr. Spyropoulos added in the interview. “The next step is dissemination.”

But thromboprophylaxis experts cautioned that, while the results looked promising, the findings need more analysis and review, and the intervention may need further testing before it’s ready for widespread use.

For example, one unexpected result was an unexpected 2.1 percentage point increase in all-cause mortality linked with use of the decision-support tool. Total deaths from admission to 30 days after discharge occurred in 9.1% of the patients treated at the two hospitals that used the risk calculator and 7.0% among the control patients, a difference that Dr, Spyropoulos said was likely the result of unbalanced outcomes from COVID-19 infections that had no relevance to the tested intervention. The trial ran during December 2020–January 2022.
 

But wait – more detail and analysis needed

“I’d like to see more analysis of the data from this trial,” and “there is the issue of increased mortality,” commented Gregory Piazza, MD, director of vascular medicine at Brigham and Women’s Hospital in Boston, and a specialist in thromboembolism prevention and management. He also highlighted the need for greater detail on the arterial thromboembolic events tallied during the study.

With more details and analysis of these findings “we’ll learn more about the true impact” of this intervention, Dr. Piazza said in an interview.

Mitchel L. Zoler/MDedge News

“The increased mortality in the intervention group may have been due to differential treatment and decision-making and confounding and warrants further investigation,” commented Elaine M. Hylek, MD, a professor at Boston University and designated discussant for the report. Selection bias may have contributed to this possible confounding, Dr. Hylek noted.

Other limitations of the study cited by Dr. Hylek included its reliance on individual clinician decision-making to actually prescribe thromboprophylaxis, a lack of information on patient adherence to their thromboprophylaxis prescription, and an overall low rate of appropriate thromboprophylaxis prescribed to patients at discharge. The rates were 7.5% among the controls and 13.6% among patients in the intervention arm. For prescription at the time of hospitalization, the rates were 72.5% among control patients and 80.1% for patients seen at the two hospitals that used the decision-support tool.
 

The IMPROVE-DD VTE risk assessment tool

The clinical decision-support tool tested is called the IMPROVE-DD VTE risk assessment model, developed over several years by Dr. Spyropoulos and associates; they have also performed multiple validation studies. The model includes eight factors that score 1-3 points if positive that can add up to total scores of 0-14. A score of 0 or 1 is considered low risk, 2 or 3 intermediate risk, and 4 or more high risk. One of the scoring factors is the result of a D-dimer test, which explains the DD part of the name.

The eight factors and point assignments are prior venous thromboembolism: 3 points; known thrombophilia: 2 points; lower limb paralysis: 2 points; current cancer: 2 points; d-dimer level more than twofold the upper limit of normal: 2 points; immobilized for at least 7 days: 1 point; admitted to the ICU or coronary care unit: 1 point; and age greater than 60 years old: 1 point.

Development of the IMPROVE-DD VTE risk calculator received most of its funding from the U.S. Agency for Healthcare Research and Quality, and the risk tool will be available for hospitals and health systems to access at no charge through the agency’s website, Dr. Spyropoulos said. The researchers designed the calculator to operate in any EHR product.

IMPROVE-DD VTE “is a very valid, high-quality tool,” commented Dr. Piazza. “We’ve used some rather blunt tools in the past,” and especially praised inclusion of D-dimer results into the IMPROVE-DD VTE model.

“It’s nice to use a biomarker in addition to clinical factors,” he said. “A biomarker provides a more holistic picture; we can’t do genetic testing on every patient.”

Enrollment focused on higher-risk patients

The study ran at four academic, tertiary-care hospitals in the Northwell Health network in the New York region. It enrolled patients aged more than 60 years who were hospitalized for any of five diagnoses: heart failure; acute respiratory insufficiency, including chronic obstructive lung disease or asthma; acute infectious disease, including COVID-19; acute inflammatory disease, including rheumatic disease; or acute stroke. The study excluded patients with a history of atrial fibrillation, those who used an anticoagulant at home, or those who had received therapeutic anticoagulation within 24 hours of their hospital admission.

The anticoagulant prophylaxis that patients received depended on their calculated risk level – intermediate or high – and whether they were inpatients or being discharged. The anticoagulants that clinicians could prescribe included unfractionated heparin, enoxaparin, fondaparinux, rivaroxaban, and apixaban.

“We’ve been looking for a long time for a tool for medically ill patients that’s like the CHA2DS2-VASc score” for patients with atrial fibrillation. “These powerful data say we now have this, and the EHR provides a vehicle to easily implement it,” Dr. Spyropoulos said.

The IMPROVE-DD VTE study received partial funding from Janssen. Dr. Spyropoulos has been a consultant to Nayer, Boehringer Ingelheim, Bristol-Myers Squibb, Janssen, Pfizer, and Sanofi; adviser to the ATLAS Group; and has received research support from Janssen. Dr. Piazza has received research funding from Bayer, BIG/EKOS, BMS, Janssen, and Portola. Dr. Hylek had been a consultant to Bayer and Ionis, and has received honoraria from Boehringer Ingelheim and Pfizer.

CHICAGO – A clinical decision-support tool designed to identify hospitalized patients who need thromboembolism prophylaxis and embedded in a hospital’s electronic health record led to significantly more appropriate prophylaxis, compared with usual care, and significantly cut the 30-day rate of thromboembolism in a randomized, multicenter trial with more than 10,000 patients.

“This is the first time that a clinical decision support tool not only changed [thromboprophylaxis prescribing] behavior but also affected hard outcomes. That’s remarkable,” lead investigator Alex C. Spyropoulos, MD, said in an interview.

Even so, outside experts expressed concerns about certain results and the trial design.

Mitchel L. Zoler/MDedge News

Use of the decision-support risk calculator for thromboembolism in the IMPROVE-DD VTE trial significantly boosted use of appropriate inpatient thromboprophylaxis starting at hospital admission by a relative 52%, and significantly increased outpatient thromboprophylaxis prescribed at discharge by a relative 93% in the study’s two primary endpoints, Dr. Spyropoulos reported at the American Heart Association scientific sessions.

This intervention led to a significant 29% relative reduction in the incidence of total thromboembolic events, both venous and arterial, during hospitalization and through 30 days post discharge.

The absolute thromboembolic event rates were 2.9% among 5,249 patients treated at either of two U.S. hospitals that used the EHR-based risk calculator and 4.0% in 5,450 patients seen at either of two other U.S. hospitals that served as controls and where usual care method identified patients who needed thromboprophylaxis, said Dr. Spyropoulos, professor and director of the anticoagulation and clinical thrombosis services for Northwell Health in New York. This included a 2.7% rate of venous thromboembolism and a 0.25% rate of arterial thromboembolism in the intervention patients, and a 3.3% rate of venous events and a 0.7% rate of arterial events in the controls.

Patients treated at the hospitals that used the EHR-embedded risk calculator also has a numerically lower rate of major bleeding events during hospitalization and 30-day postdischarge follow-up, a 0.15% rate compared with a 0.22% rate in the control patients, a difference that was not significant.
 

A ‘powerful message’

“It’s a powerful message to see an absolute 1.1% difference in the rate of thromboembolism and a trend to fewer major bleeds. I think this will change practice,” Dr. Spyropoulos added in the interview. “The next step is dissemination.”

But thromboprophylaxis experts cautioned that, while the results looked promising, the findings need more analysis and review, and the intervention may need further testing before it’s ready for widespread use.

For example, one unexpected result was an unexpected 2.1 percentage point increase in all-cause mortality linked with use of the decision-support tool. Total deaths from admission to 30 days after discharge occurred in 9.1% of the patients treated at the two hospitals that used the risk calculator and 7.0% among the control patients, a difference that Dr, Spyropoulos said was likely the result of unbalanced outcomes from COVID-19 infections that had no relevance to the tested intervention. The trial ran during December 2020–January 2022.
 

But wait – more detail and analysis needed

“I’d like to see more analysis of the data from this trial,” and “there is the issue of increased mortality,” commented Gregory Piazza, MD, director of vascular medicine at Brigham and Women’s Hospital in Boston, and a specialist in thromboembolism prevention and management. He also highlighted the need for greater detail on the arterial thromboembolic events tallied during the study.

With more details and analysis of these findings “we’ll learn more about the true impact” of this intervention, Dr. Piazza said in an interview.

Mitchel L. Zoler/MDedge News

“The increased mortality in the intervention group may have been due to differential treatment and decision-making and confounding and warrants further investigation,” commented Elaine M. Hylek, MD, a professor at Boston University and designated discussant for the report. Selection bias may have contributed to this possible confounding, Dr. Hylek noted.

Other limitations of the study cited by Dr. Hylek included its reliance on individual clinician decision-making to actually prescribe thromboprophylaxis, a lack of information on patient adherence to their thromboprophylaxis prescription, and an overall low rate of appropriate thromboprophylaxis prescribed to patients at discharge. The rates were 7.5% among the controls and 13.6% among patients in the intervention arm. For prescription at the time of hospitalization, the rates were 72.5% among control patients and 80.1% for patients seen at the two hospitals that used the decision-support tool.
 

The IMPROVE-DD VTE risk assessment tool

The clinical decision-support tool tested is called the IMPROVE-DD VTE risk assessment model, developed over several years by Dr. Spyropoulos and associates; they have also performed multiple validation studies. The model includes eight factors that score 1-3 points if positive that can add up to total scores of 0-14. A score of 0 or 1 is considered low risk, 2 or 3 intermediate risk, and 4 or more high risk. One of the scoring factors is the result of a D-dimer test, which explains the DD part of the name.

The eight factors and point assignments are prior venous thromboembolism: 3 points; known thrombophilia: 2 points; lower limb paralysis: 2 points; current cancer: 2 points; d-dimer level more than twofold the upper limit of normal: 2 points; immobilized for at least 7 days: 1 point; admitted to the ICU or coronary care unit: 1 point; and age greater than 60 years old: 1 point.

Development of the IMPROVE-DD VTE risk calculator received most of its funding from the U.S. Agency for Healthcare Research and Quality, and the risk tool will be available for hospitals and health systems to access at no charge through the agency’s website, Dr. Spyropoulos said. The researchers designed the calculator to operate in any EHR product.

IMPROVE-DD VTE “is a very valid, high-quality tool,” commented Dr. Piazza. “We’ve used some rather blunt tools in the past,” and especially praised inclusion of D-dimer results into the IMPROVE-DD VTE model.

“It’s nice to use a biomarker in addition to clinical factors,” he said. “A biomarker provides a more holistic picture; we can’t do genetic testing on every patient.”

Enrollment focused on higher-risk patients

The study ran at four academic, tertiary-care hospitals in the Northwell Health network in the New York region. It enrolled patients aged more than 60 years who were hospitalized for any of five diagnoses: heart failure; acute respiratory insufficiency, including chronic obstructive lung disease or asthma; acute infectious disease, including COVID-19; acute inflammatory disease, including rheumatic disease; or acute stroke. The study excluded patients with a history of atrial fibrillation, those who used an anticoagulant at home, or those who had received therapeutic anticoagulation within 24 hours of their hospital admission.

The anticoagulant prophylaxis that patients received depended on their calculated risk level – intermediate or high – and whether they were inpatients or being discharged. The anticoagulants that clinicians could prescribe included unfractionated heparin, enoxaparin, fondaparinux, rivaroxaban, and apixaban.

“We’ve been looking for a long time for a tool for medically ill patients that’s like the CHA2DS2-VASc score” for patients with atrial fibrillation. “These powerful data say we now have this, and the EHR provides a vehicle to easily implement it,” Dr. Spyropoulos said.

The IMPROVE-DD VTE study received partial funding from Janssen. Dr. Spyropoulos has been a consultant to Nayer, Boehringer Ingelheim, Bristol-Myers Squibb, Janssen, Pfizer, and Sanofi; adviser to the ATLAS Group; and has received research support from Janssen. Dr. Piazza has received research funding from Bayer, BIG/EKOS, BMS, Janssen, and Portola. Dr. Hylek had been a consultant to Bayer and Ionis, and has received honoraria from Boehringer Ingelheim and Pfizer.

A study evaluating a new approach using a combination of two thrombolytics designed to reduce bleeding risk in patients with acute ischemic stroke has not shown any benefit on the primary outcome of all intracranial hemorrhage (ICH).

However, there were some encouraging findings including a trend towards a reduction in symptomatic ICH, researchers report, and the combination approach did not show any depletion of fibrinogen levels, which suggests a potential lower bleeding risk.

“Although the main results of this study are neutral, we are encouraged that the combination approach with a low dose of alteplase followed by the new mutant pro-urokinase product looked as effective as full-dose alteplase alone, and there were some promising signs signaling a potential lower bleeding risk,” senior investigator, Diederik Dippel, MD, Erasmus University Medical Center, Rotterdam, the Netherlands, told this news organization.  

The DUMAS study (Dual Thrombolytic Therapy With Mutant Pro-Urokinase and Low Dose Alteplase for Ischemic Stroke) was presented at the World Stroke Congress in Singapore by study coauthor Nadinda van der Ende, MD, also from Erasmus University Medical Center. 

She pointed out that thrombolysis with intravenous alteplase increases the likelihood of a good outcome in acute ischemic stroke but can cause symptomatic intracranial hemorrhage, which can be associated with death and major disability.

Mutant pro-urokinase is a new thrombolytic agent, in development by Thrombolytic Science, Cambridge, Mass., formed by changing one amino acid in pro-urokinase to make it more stable. It is more fibrin specific than alteplase and therefore believed to have a lower risk of intracranial hemorrhage.

Fibrin is formed as the last step in the clotting process, and the precursor of fibrin in the blood is fibrinogen, Dr. van der Ende noted. Alteplase depletes fibrinogen, contributing to its increased bleeding risk, but mutant pro-urokinase is not believed to affect fibrinogen.

“Mutant pro-urokinase does not bind to intact fibrin. It only binds to fibrin that has already been primed by alteplase,” she explained.

The hypothesis behind the current study is that giving a small dose of alteplase will break down fibrin in the clot enough to expose the binding sites for mutant pro-urokinase, which can then be given to continue to lyse the clot.  

As alteplase has a short half-life, it disappears quickly, and new fibrin is not affected. As mutant pro-urokinase can only lyse fibrin that is primed with alteplase, new hemostatic clots should stay intact. Animal studies have shown less bleeding from distant sites with this approach, Dr. van der Ende said.

The primary analysis of the phase 2 DUMAS study included 238 patients with mild ischemic stroke (median National Institutes of Health Stroke Scale [NIHSS] score 3) who met the standard criteria for IV alteplase.

They were randomized to alteplase alone at the regular dose of 0.9 mg/kg (max 90 mg) with a 10% bolus and the remaining given over 60 minutes; or to a combination of a 5-mg bolus of IV alteplase followed by mutant pro-urokinase at a dose of 40 mg given over 60 minutes.

The primary outcome was the rate of all intracranial hemorrhage (symptomatic and asymptomatic) detected by neuroimaging.  

This occurred in 14% of patients in the full-dose alteplase group vs. 13% of patients in the combined alteplase/mutant pro-urokinase group, a nonsignificant difference: adjusted odds ratio, 0.99 (95% confidence interval, 0.46-2.14).

Secondary outcomes showed no significant differences in NIHSS scores at 24 hours or 5-7 days; functional outcome as measured by a shift analysis of the Modified Rankin Scale (mRS); final infarct volume; or perfusion deficit.

However, blood fibrinogen levels were not depleted and significantly higher in the alteplase/mutant pro-urokinase group than in the full-dose alteplase alone group.

In terms of safety, symptomatic ICH occurred in three patients in the alteplase group (3%) and in none (0%) in the combined alteplase/mutant pro-urokinase group; death occurred in 4% vs. 2% patients respectively; and major extracranial hemorrhage occurred in 1% in both groups.

Dr. Van der Ende concluded that the study showed an overall low rate of ICH; a combination of alteplase and mutant pro-urokinase was not superior to alteplase alone in reducing ICH rates in this population of patients with minor stroke; and mutant pro-urokinase appeared to be safe and, unlike alteplase, did not show any reduction in fibrinogen levels.

“We think the lack of an effect on fibrinogen with this new combination of a small alteplase bolus followed by mutant pro-urokinase infusion is promising,” Dr. Dippel commented. “The fact that there was no symptomatic ICH with the combination treatment is also encouraging. Although the primary endpoint of this trial was neutral, we still believe this is a very interesting approach, with the potential for reduced bleeding, compared with alteplase alone, but we need larger numbers to see an effect on outcomes.”

Dr. Dippel also pointed out that the study included only patients with minor stroke who were not eligible for endovascular therapy, and these patients have a low risk of a poor outcome and a low bleeding risk. 

They are hoping to do another study in patients with more severe stroke, who have a higher bleeding risk and would have more to gain from this combination approach.

Because many patients with severe stroke now have immediate thrombectomy if they present to a comprehensive stroke center, a trial in severe stroke patients would have to be done in primary stroke centers, so if the patents are referred to thrombectomy, the thrombolytic would have a chance to work, Dr. Dippel added.

Commenting on the study for this news organization, Stefan Kiechl, MD, Medical University of Innsbruck (Austria), who is cochair of the World Stroke Congress scientific committee, said, “Alteplase is not fibrin specific, and also causes a degeneration of fibrinogen, which results in ‘fibrinogen depletion coagulopathy.’ It is assumed that 20%-40% of intracerebral bleeding after thrombolysis with alteplase is caused by this problem. DUMAS tests the combination of a substantially reduced alteplase [5 mg] dose plus mutant pro-urokinase to avoid this problem.”

The new thrombolysis protocol, however, did not result in a lower bleeding risk, compared to the comparator alteplase,” he added. “The main limitation of this study is that mainly patients with minor strokes were included. Patients with moderate and severe strokes, who have a substantial risk of bleeding, were not adequately addressed.”

The DUMAS trial was funded by an unrestricted grant from Thrombolytic Science, paid to the institution. Dr. Van der Ende and Dr. Dippel report no relevant disclosures.
 

A version of this article first appeared on Medscape.com.

A study evaluating a new approach using a combination of two thrombolytics designed to reduce bleeding risk in patients with acute ischemic stroke has not shown any benefit on the primary outcome of all intracranial hemorrhage (ICH).

However, there were some encouraging findings including a trend towards a reduction in symptomatic ICH, researchers report, and the combination approach did not show any depletion of fibrinogen levels, which suggests a potential lower bleeding risk.

“Although the main results of this study are neutral, we are encouraged that the combination approach with a low dose of alteplase followed by the new mutant pro-urokinase product looked as effective as full-dose alteplase alone, and there were some promising signs signaling a potential lower bleeding risk,” senior investigator, Diederik Dippel, MD, Erasmus University Medical Center, Rotterdam, the Netherlands, told this news organization.  

The DUMAS study (Dual Thrombolytic Therapy With Mutant Pro-Urokinase and Low Dose Alteplase for Ischemic Stroke) was presented at the World Stroke Congress in Singapore by study coauthor Nadinda van der Ende, MD, also from Erasmus University Medical Center. 

She pointed out that thrombolysis with intravenous alteplase increases the likelihood of a good outcome in acute ischemic stroke but can cause symptomatic intracranial hemorrhage, which can be associated with death and major disability.

Mutant pro-urokinase is a new thrombolytic agent, in development by Thrombolytic Science, Cambridge, Mass., formed by changing one amino acid in pro-urokinase to make it more stable. It is more fibrin specific than alteplase and therefore believed to have a lower risk of intracranial hemorrhage.

Fibrin is formed as the last step in the clotting process, and the precursor of fibrin in the blood is fibrinogen, Dr. van der Ende noted. Alteplase depletes fibrinogen, contributing to its increased bleeding risk, but mutant pro-urokinase is not believed to affect fibrinogen.

“Mutant pro-urokinase does not bind to intact fibrin. It only binds to fibrin that has already been primed by alteplase,” she explained.

The hypothesis behind the current study is that giving a small dose of alteplase will break down fibrin in the clot enough to expose the binding sites for mutant pro-urokinase, which can then be given to continue to lyse the clot.  

As alteplase has a short half-life, it disappears quickly, and new fibrin is not affected. As mutant pro-urokinase can only lyse fibrin that is primed with alteplase, new hemostatic clots should stay intact. Animal studies have shown less bleeding from distant sites with this approach, Dr. van der Ende said.

The primary analysis of the phase 2 DUMAS study included 238 patients with mild ischemic stroke (median National Institutes of Health Stroke Scale [NIHSS] score 3) who met the standard criteria for IV alteplase.

They were randomized to alteplase alone at the regular dose of 0.9 mg/kg (max 90 mg) with a 10% bolus and the remaining given over 60 minutes; or to a combination of a 5-mg bolus of IV alteplase followed by mutant pro-urokinase at a dose of 40 mg given over 60 minutes.

The primary outcome was the rate of all intracranial hemorrhage (symptomatic and asymptomatic) detected by neuroimaging.  

This occurred in 14% of patients in the full-dose alteplase group vs. 13% of patients in the combined alteplase/mutant pro-urokinase group, a nonsignificant difference: adjusted odds ratio, 0.99 (95% confidence interval, 0.46-2.14).

Secondary outcomes showed no significant differences in NIHSS scores at 24 hours or 5-7 days; functional outcome as measured by a shift analysis of the Modified Rankin Scale (mRS); final infarct volume; or perfusion deficit.

However, blood fibrinogen levels were not depleted and significantly higher in the alteplase/mutant pro-urokinase group than in the full-dose alteplase alone group.

In terms of safety, symptomatic ICH occurred in three patients in the alteplase group (3%) and in none (0%) in the combined alteplase/mutant pro-urokinase group; death occurred in 4% vs. 2% patients respectively; and major extracranial hemorrhage occurred in 1% in both groups.

Dr. Van der Ende concluded that the study showed an overall low rate of ICH; a combination of alteplase and mutant pro-urokinase was not superior to alteplase alone in reducing ICH rates in this population of patients with minor stroke; and mutant pro-urokinase appeared to be safe and, unlike alteplase, did not show any reduction in fibrinogen levels.

“We think the lack of an effect on fibrinogen with this new combination of a small alteplase bolus followed by mutant pro-urokinase infusion is promising,” Dr. Dippel commented. “The fact that there was no symptomatic ICH with the combination treatment is also encouraging. Although the primary endpoint of this trial was neutral, we still believe this is a very interesting approach, with the potential for reduced bleeding, compared with alteplase alone, but we need larger numbers to see an effect on outcomes.”

Dr. Dippel also pointed out that the study included only patients with minor stroke who were not eligible for endovascular therapy, and these patients have a low risk of a poor outcome and a low bleeding risk. 

They are hoping to do another study in patients with more severe stroke, who have a higher bleeding risk and would have more to gain from this combination approach.

Because many patients with severe stroke now have immediate thrombectomy if they present to a comprehensive stroke center, a trial in severe stroke patients would have to be done in primary stroke centers, so if the patents are referred to thrombectomy, the thrombolytic would have a chance to work, Dr. Dippel added.

Commenting on the study for this news organization, Stefan Kiechl, MD, Medical University of Innsbruck (Austria), who is cochair of the World Stroke Congress scientific committee, said, “Alteplase is not fibrin specific, and also causes a degeneration of fibrinogen, which results in ‘fibrinogen depletion coagulopathy.’ It is assumed that 20%-40% of intracerebral bleeding after thrombolysis with alteplase is caused by this problem. DUMAS tests the combination of a substantially reduced alteplase [5 mg] dose plus mutant pro-urokinase to avoid this problem.”

The new thrombolysis protocol, however, did not result in a lower bleeding risk, compared to the comparator alteplase,” he added. “The main limitation of this study is that mainly patients with minor strokes were included. Patients with moderate and severe strokes, who have a substantial risk of bleeding, were not adequately addressed.”

The DUMAS trial was funded by an unrestricted grant from Thrombolytic Science, paid to the institution. Dr. Van der Ende and Dr. Dippel report no relevant disclosures.
 

A version of this article first appeared on Medscape.com.

A study evaluating a new approach using a combination of two thrombolytics designed to reduce bleeding risk in patients with acute ischemic stroke has not shown any benefit on the primary outcome of all intracranial hemorrhage (ICH).

However, there were some encouraging findings including a trend towards a reduction in symptomatic ICH, researchers report, and the combination approach did not show any depletion of fibrinogen levels, which suggests a potential lower bleeding risk.

“Although the main results of this study are neutral, we are encouraged that the combination approach with a low dose of alteplase followed by the new mutant pro-urokinase product looked as effective as full-dose alteplase alone, and there were some promising signs signaling a potential lower bleeding risk,” senior investigator, Diederik Dippel, MD, Erasmus University Medical Center, Rotterdam, the Netherlands, told this news organization.  

The DUMAS study (Dual Thrombolytic Therapy With Mutant Pro-Urokinase and Low Dose Alteplase for Ischemic Stroke) was presented at the World Stroke Congress in Singapore by study coauthor Nadinda van der Ende, MD, also from Erasmus University Medical Center. 

She pointed out that thrombolysis with intravenous alteplase increases the likelihood of a good outcome in acute ischemic stroke but can cause symptomatic intracranial hemorrhage, which can be associated with death and major disability.

Mutant pro-urokinase is a new thrombolytic agent, in development by Thrombolytic Science, Cambridge, Mass., formed by changing one amino acid in pro-urokinase to make it more stable. It is more fibrin specific than alteplase and therefore believed to have a lower risk of intracranial hemorrhage.

Fibrin is formed as the last step in the clotting process, and the precursor of fibrin in the blood is fibrinogen, Dr. van der Ende noted. Alteplase depletes fibrinogen, contributing to its increased bleeding risk, but mutant pro-urokinase is not believed to affect fibrinogen.

“Mutant pro-urokinase does not bind to intact fibrin. It only binds to fibrin that has already been primed by alteplase,” she explained.

The hypothesis behind the current study is that giving a small dose of alteplase will break down fibrin in the clot enough to expose the binding sites for mutant pro-urokinase, which can then be given to continue to lyse the clot.  

As alteplase has a short half-life, it disappears quickly, and new fibrin is not affected. As mutant pro-urokinase can only lyse fibrin that is primed with alteplase, new hemostatic clots should stay intact. Animal studies have shown less bleeding from distant sites with this approach, Dr. van der Ende said.

The primary analysis of the phase 2 DUMAS study included 238 patients with mild ischemic stroke (median National Institutes of Health Stroke Scale [NIHSS] score 3) who met the standard criteria for IV alteplase.

They were randomized to alteplase alone at the regular dose of 0.9 mg/kg (max 90 mg) with a 10% bolus and the remaining given over 60 minutes; or to a combination of a 5-mg bolus of IV alteplase followed by mutant pro-urokinase at a dose of 40 mg given over 60 minutes.

The primary outcome was the rate of all intracranial hemorrhage (symptomatic and asymptomatic) detected by neuroimaging.  

This occurred in 14% of patients in the full-dose alteplase group vs. 13% of patients in the combined alteplase/mutant pro-urokinase group, a nonsignificant difference: adjusted odds ratio, 0.99 (95% confidence interval, 0.46-2.14).

Secondary outcomes showed no significant differences in NIHSS scores at 24 hours or 5-7 days; functional outcome as measured by a shift analysis of the Modified Rankin Scale (mRS); final infarct volume; or perfusion deficit.

However, blood fibrinogen levels were not depleted and significantly higher in the alteplase/mutant pro-urokinase group than in the full-dose alteplase alone group.

In terms of safety, symptomatic ICH occurred in three patients in the alteplase group (3%) and in none (0%) in the combined alteplase/mutant pro-urokinase group; death occurred in 4% vs. 2% patients respectively; and major extracranial hemorrhage occurred in 1% in both groups.

Dr. Van der Ende concluded that the study showed an overall low rate of ICH; a combination of alteplase and mutant pro-urokinase was not superior to alteplase alone in reducing ICH rates in this population of patients with minor stroke; and mutant pro-urokinase appeared to be safe and, unlike alteplase, did not show any reduction in fibrinogen levels.

“We think the lack of an effect on fibrinogen with this new combination of a small alteplase bolus followed by mutant pro-urokinase infusion is promising,” Dr. Dippel commented. “The fact that there was no symptomatic ICH with the combination treatment is also encouraging. Although the primary endpoint of this trial was neutral, we still believe this is a very interesting approach, with the potential for reduced bleeding, compared with alteplase alone, but we need larger numbers to see an effect on outcomes.”

Dr. Dippel also pointed out that the study included only patients with minor stroke who were not eligible for endovascular therapy, and these patients have a low risk of a poor outcome and a low bleeding risk. 

They are hoping to do another study in patients with more severe stroke, who have a higher bleeding risk and would have more to gain from this combination approach.

Because many patients with severe stroke now have immediate thrombectomy if they present to a comprehensive stroke center, a trial in severe stroke patients would have to be done in primary stroke centers, so if the patents are referred to thrombectomy, the thrombolytic would have a chance to work, Dr. Dippel added.

Commenting on the study for this news organization, Stefan Kiechl, MD, Medical University of Innsbruck (Austria), who is cochair of the World Stroke Congress scientific committee, said, “Alteplase is not fibrin specific, and also causes a degeneration of fibrinogen, which results in ‘fibrinogen depletion coagulopathy.’ It is assumed that 20%-40% of intracerebral bleeding after thrombolysis with alteplase is caused by this problem. DUMAS tests the combination of a substantially reduced alteplase [5 mg] dose plus mutant pro-urokinase to avoid this problem.”

The new thrombolysis protocol, however, did not result in a lower bleeding risk, compared to the comparator alteplase,” he added. “The main limitation of this study is that mainly patients with minor strokes were included. Patients with moderate and severe strokes, who have a substantial risk of bleeding, were not adequately addressed.”

The DUMAS trial was funded by an unrestricted grant from Thrombolytic Science, paid to the institution. Dr. Van der Ende and Dr. Dippel report no relevant disclosures.
 

A version of this article first appeared on Medscape.com.

A commonly prescribed direct oral anticoagulant (DOAC) has the lowest risk of bleeding, say researchers. Used to prevent strokes in those with atrial fibrillation (AFib), DOACs have recently become more common than warfarin, the previous standard treatment, as they do not require as much follow-up monitoring – which was “particularly valuable” during the COVID-19 pandemic – and have “less risk” of side effects, highlighted the authors of a new study, published in Annals of Internal Medicine.

However, the authors explained that, although current guidelines recommend using DOACs over warfarin in patients with AFib, “head-to-head trial data do not exist to guide the choice of DOAC.” So, they set out to try and fill this evidence gap by doing a large-scale comparison between all DOACs – apixaban, dabigatran, edoxaban, and rivaroxaban – in routine clinical practice.

Wallis Lau, PhD, University College London, and co–lead author, said: “Direct oral anticoagulants have been prescribed with increasing frequency worldwide in recent years, but evidence comparing them directly has been limited.”
 

One drug stood out

For the multinational population-based cohort study the researchers compared the efficacy and risk of side effects for the four most common DOACs. They reviewed data – from five standardized electronic health care databases that covered 221 million people in the United Kingdom, France, Germany, and the United States – of 527,226 patients who had been newly diagnosed with AFib between 2010 and 2019, and who had received a new DOAC prescription. The study included 281,320 apixaban users, 61,008 dabigatran users, 12,722 edoxaban users, and 172,176 rivaroxaban users.

Database-specific hazard ratios of ischemic stroke or systemic embolism, intracranial hemorrhage, gastrointestinal bleeding, and all-cause mortality between DOACs were estimated using a Cox regression model stratified by propensity score and pooled using a random-effects model.

In total, 9,530 ischemic stroke or systemic embolism events, 841 intercranial hemorrhage events, 8,319 gastrointestinal bleeding events, and 1,476 deaths were identified over the study follow-up. The researchers found that all four drugs were comparable on outcomes for ischemic stroke, intercranial hemorrhage, and all-cause mortality.

However, they identified a difference in the risk of gastrointestinal bleeding, which they highlighted “is one of the most common and concerning side effects of DOACs.”

“Apixaban stood out as having lower risk of gastrointestinal bleeding,” said the authors, with a 19%-28% lower risk when compared directly with each of the other three DOACs. Specifically, apixaban use was associated with lower risk for gastrointestinal bleeding than use of dabigatran (HR, 0.81; 95% confidence interval, 0.70-0.94), edoxaban (HR, 0.77; 95% CI, 0.66-0.91), or rivaroxaban (HR, 0.72; 95% CI, 0.66-0.79).

The researchers also highlighted that their findings held true when looking at data only from those aged over 80, and those with chronic kidney disease, two groups that are “often underrepresented” in clinical trials.
 

Apixaban may be preferable

The researchers concluded that, among patients with AFib, apixaban use was associated with lower risk for gastrointestinal bleeding and similar rates of ischemic stroke or systemic embolism, intracranial hemorrhage and all-cause mortality, compared with dabigatran, edoxaban, and rivaroxaban.

“Our results indicate that apixaban may be preferable to other blood thinners because of the lower rate of gastrointestinal bleeding and similar rates of stroke, a finding that we hope will be supported by randomized controlled trials,” said Dr. Lau.

However, he emphasized that, “as with all medications, potential risks and benefits can differ between people, so considering the full spectrum of outcomes and side effects will still be necessary for each individual patient.”

The authors all declared no conflicting interests.

A version of this article first appeared on Medscape UK.

A commonly prescribed direct oral anticoagulant (DOAC) has the lowest risk of bleeding, say researchers. Used to prevent strokes in those with atrial fibrillation (AFib), DOACs have recently become more common than warfarin, the previous standard treatment, as they do not require as much follow-up monitoring – which was “particularly valuable” during the COVID-19 pandemic – and have “less risk” of side effects, highlighted the authors of a new study, published in Annals of Internal Medicine.

However, the authors explained that, although current guidelines recommend using DOACs over warfarin in patients with AFib, “head-to-head trial data do not exist to guide the choice of DOAC.” So, they set out to try and fill this evidence gap by doing a large-scale comparison between all DOACs – apixaban, dabigatran, edoxaban, and rivaroxaban – in routine clinical practice.

Wallis Lau, PhD, University College London, and co–lead author, said: “Direct oral anticoagulants have been prescribed with increasing frequency worldwide in recent years, but evidence comparing them directly has been limited.”
 

One drug stood out

For the multinational population-based cohort study the researchers compared the efficacy and risk of side effects for the four most common DOACs. They reviewed data – from five standardized electronic health care databases that covered 221 million people in the United Kingdom, France, Germany, and the United States – of 527,226 patients who had been newly diagnosed with AFib between 2010 and 2019, and who had received a new DOAC prescription. The study included 281,320 apixaban users, 61,008 dabigatran users, 12,722 edoxaban users, and 172,176 rivaroxaban users.

Database-specific hazard ratios of ischemic stroke or systemic embolism, intracranial hemorrhage, gastrointestinal bleeding, and all-cause mortality between DOACs were estimated using a Cox regression model stratified by propensity score and pooled using a random-effects model.

In total, 9,530 ischemic stroke or systemic embolism events, 841 intercranial hemorrhage events, 8,319 gastrointestinal bleeding events, and 1,476 deaths were identified over the study follow-up. The researchers found that all four drugs were comparable on outcomes for ischemic stroke, intercranial hemorrhage, and all-cause mortality.

However, they identified a difference in the risk of gastrointestinal bleeding, which they highlighted “is one of the most common and concerning side effects of DOACs.”

“Apixaban stood out as having lower risk of gastrointestinal bleeding,” said the authors, with a 19%-28% lower risk when compared directly with each of the other three DOACs. Specifically, apixaban use was associated with lower risk for gastrointestinal bleeding than use of dabigatran (HR, 0.81; 95% confidence interval, 0.70-0.94), edoxaban (HR, 0.77; 95% CI, 0.66-0.91), or rivaroxaban (HR, 0.72; 95% CI, 0.66-0.79).

The researchers also highlighted that their findings held true when looking at data only from those aged over 80, and those with chronic kidney disease, two groups that are “often underrepresented” in clinical trials.
 

Apixaban may be preferable

The researchers concluded that, among patients with AFib, apixaban use was associated with lower risk for gastrointestinal bleeding and similar rates of ischemic stroke or systemic embolism, intracranial hemorrhage and all-cause mortality, compared with dabigatran, edoxaban, and rivaroxaban.

“Our results indicate that apixaban may be preferable to other blood thinners because of the lower rate of gastrointestinal bleeding and similar rates of stroke, a finding that we hope will be supported by randomized controlled trials,” said Dr. Lau.

However, he emphasized that, “as with all medications, potential risks and benefits can differ between people, so considering the full spectrum of outcomes and side effects will still be necessary for each individual patient.”

The authors all declared no conflicting interests.

A version of this article first appeared on Medscape UK.

A commonly prescribed direct oral anticoagulant (DOAC) has the lowest risk of bleeding, say researchers. Used to prevent strokes in those with atrial fibrillation (AFib), DOACs have recently become more common than warfarin, the previous standard treatment, as they do not require as much follow-up monitoring – which was “particularly valuable” during the COVID-19 pandemic – and have “less risk” of side effects, highlighted the authors of a new study, published in Annals of Internal Medicine.

However, the authors explained that, although current guidelines recommend using DOACs over warfarin in patients with AFib, “head-to-head trial data do not exist to guide the choice of DOAC.” So, they set out to try and fill this evidence gap by doing a large-scale comparison between all DOACs – apixaban, dabigatran, edoxaban, and rivaroxaban – in routine clinical practice.

Wallis Lau, PhD, University College London, and co–lead author, said: “Direct oral anticoagulants have been prescribed with increasing frequency worldwide in recent years, but evidence comparing them directly has been limited.”
 

One drug stood out

For the multinational population-based cohort study the researchers compared the efficacy and risk of side effects for the four most common DOACs. They reviewed data – from five standardized electronic health care databases that covered 221 million people in the United Kingdom, France, Germany, and the United States – of 527,226 patients who had been newly diagnosed with AFib between 2010 and 2019, and who had received a new DOAC prescription. The study included 281,320 apixaban users, 61,008 dabigatran users, 12,722 edoxaban users, and 172,176 rivaroxaban users.

Database-specific hazard ratios of ischemic stroke or systemic embolism, intracranial hemorrhage, gastrointestinal bleeding, and all-cause mortality between DOACs were estimated using a Cox regression model stratified by propensity score and pooled using a random-effects model.

In total, 9,530 ischemic stroke or systemic embolism events, 841 intercranial hemorrhage events, 8,319 gastrointestinal bleeding events, and 1,476 deaths were identified over the study follow-up. The researchers found that all four drugs were comparable on outcomes for ischemic stroke, intercranial hemorrhage, and all-cause mortality.

However, they identified a difference in the risk of gastrointestinal bleeding, which they highlighted “is one of the most common and concerning side effects of DOACs.”

“Apixaban stood out as having lower risk of gastrointestinal bleeding,” said the authors, with a 19%-28% lower risk when compared directly with each of the other three DOACs. Specifically, apixaban use was associated with lower risk for gastrointestinal bleeding than use of dabigatran (HR, 0.81; 95% confidence interval, 0.70-0.94), edoxaban (HR, 0.77; 95% CI, 0.66-0.91), or rivaroxaban (HR, 0.72; 95% CI, 0.66-0.79).

The researchers also highlighted that their findings held true when looking at data only from those aged over 80, and those with chronic kidney disease, two groups that are “often underrepresented” in clinical trials.
 

Apixaban may be preferable

The researchers concluded that, among patients with AFib, apixaban use was associated with lower risk for gastrointestinal bleeding and similar rates of ischemic stroke or systemic embolism, intracranial hemorrhage and all-cause mortality, compared with dabigatran, edoxaban, and rivaroxaban.

“Our results indicate that apixaban may be preferable to other blood thinners because of the lower rate of gastrointestinal bleeding and similar rates of stroke, a finding that we hope will be supported by randomized controlled trials,” said Dr. Lau.

However, he emphasized that, “as with all medications, potential risks and benefits can differ between people, so considering the full spectrum of outcomes and side effects will still be necessary for each individual patient.”

The authors all declared no conflicting interests.

A version of this article first appeared on Medscape UK.

Patients with acute ischemic stroke presenting late at the hospital can be selected for endovascular thrombectomy by the presence of collateral flow on CT angiography (CTA), a new study shows.

The MR CLEAN-LATE trial found that patients selected for thrombectomy in this way had a greater chance of a better functional outcome than patients who did not receive endovascular therapy.

The study was presented at the 14th World Stroke Congress in Singapore by study investigator Susanne Olthuis, MD, of Maastricht (the Netherlands) University Medical Center.

Patients in the intervention group were more likely to show a benefit on the primary endpoint of modified Rankin Scale (mRS) score at 90 days with a significant common odds ratio of 1.68, a finding that received applause from attendees of the plenary WSC session at which the study was presented.

“This means that patients treated with endovascular therapy in this trial had about a 1.7 times higher chance of achieving a better functional outcome at 90 days,” Dr. Olthuis said.

“Selection based on collateral flow identifies an additional group of patients eligible for late-window endovascular therapy in addition to those eligible based on perfusion and clinical criteria,” Dr. Olthuis concluded.

“We recommend implementation of collateral selection in routine clinical practice as it is time efficient. The CTA is already available, and it involves a low-complexity assessment. The only distinction that needs to be made is whether or not there are any collaterals visible on CTA. If collaterals are absent or there is any doubt, then CT perfusion [CTP] imaging can still be used,” she added.

Co–principal investigator Wim H. van Zwam, MD, interventional radiologist at Maastricht, said in a comment:“My take-home message is that now in the late window we can select patients based on the presence of collaterals on CT angiography, which makes selection easier and faster and more widely available.

“If any collaterals are seen – and that is easily done just by looking at the CTA scan – then the patient can be selected for endovascular treatment,” Dr. van Zwam added. “We don’t need to wait for calculations of core and penumbra volumes from the CTP scan. There will also be additional patients who can benefit from endovascular therapy who do not fulfill the CTP criteria but do have visible collaterals.”

Explaining the background to the study, Dr. Olthuis noted that endovascular thrombectomy for large vessel occlusion stroke is safe and effective if performed within 6 hours and the effect then diminishes over time. In the original trial of endovascular treatment, MR CLEAN, patients with higher collateral grades had more treatment benefit, leading to the hypothesis that the assessment of collateral blood flow could help identify patients who would still benefit in the late time window.

The current MR CLEAN-LATE trial therefore set out to compare safety and efficacy of endovascular therapy in patients with acute ischemic stroke in the anterior circulation presenting within 6-24 hours from symptom onset with patients selected based on the presence of collateral flow on CTA.

At the time the trial was starting, the DAWN and DEFUSE 3 trials reported showing benefit of endovascular therapy in patients presenting in the late window who had been selected for endovascular treatment based on a combination of perfusion imaging and clinical criteria, so patients who fitted these criteria were also excluded from MR CLEAN-LATE as they would now be eligible for endovascular therapy under the latest clinical guidelines. 

But the study continued, as “we believed collateral selection may still be able to identify an additional group of patients that may benefit from endovascular therapy in the late window,” Dr. Olthuis said.

The trial randomly assigned 502 such patients with a National Institutes of Health Stroke Scale (NIHSS) score of at least 2 and with collateral flow grades of 1-3 to receive endovascular therapy (intervention) or control.

Safety data showed a slightly but nonsignificantly higher mortality rate at 90 days in the control group (30%) versus 24% in the intervention group.

The rate of symptomatic intracranial hemorrhage was higher in the intervention group (6.7%) versus 1.6% in the control group, but Dr. Olthuis pointed out that the rate of sICH in the intervention group was similar to that in the endovascular groups of the DAWN and DEFUSE 3 trials.

The primary endpoint – mRS score at 90 days – showed a shift toward better outcome in the intervention group, with an adjusted common OR of 1.68 (95% confidence interval, 1.21-2.33).

The median mRS score in the intervention group was 3 (95% CI, 2-5) versus 4 (95% CI, 2-6) in the control group.

Secondary outcomes also showed benefits for the intervention group for the endpoints of mRS score 0-1 versus 2-6 (OR, 1.63); mRS 0-2 versus 3-6 (OR 1.54); and mRS 0-3 versus 4-6 (OR, 1.74).

In addition, NIHSS score was reduced by 17% at 24 hours and by 27% by 5-7 days or discharge in the intervention group. Recanalization at 24 hours was also improved in the intervention group (81% vs. 52%) and infarct size was reduced by 32%.

Dr. Olthuis explained that collateral grade was defined as the amount of collateral flow in the affected hemisphere as a percentage of the contralateral site, with grade 0 correlating to an absence of collaterals (and these were the only patients excluded).

Grade 1 included patients with 50% or less collaterals, grade 2 more than 50%, and grade 3 excellent collaterals – around 100%. “We included grade 1, 2 and 3, and subgroup analysis suggested no treatment interactions between different collateral grades in the patients included,” she said.

Dr. van Zwam noted that there has been evidence from other studies suggesting that the presence of collateral flow could be used to select patients for late thrombectomy, but MR CLEAN-LATE is the first randomized trial to show this and provides confirmation that this strategy is valid.

“Our results show that patients can be selected with just standard CT angiography imaging and that CT perfusion is not necessary. This will make it easier and faster to select patients especially for centers in low-resource areas who do not yet have CT perfusion imaging,” he commented.

“But even in centers where CT perfusion imaging is performed, these results should mean that we do not have to wait to analyze these results before going ahead with thrombectomy. It will also give us an additional tool, as some patients do not meet the criteria on perfusion imaging but still have identifiable collaterals and thus would now qualify for endovascular thrombectomy,” he added.
 

Could collateral assessment replace CT perfusion?

Commenting on the MR CLEAN-LATE trial, Stefan Kiechl, MD, Medical University of Innsbruck (Austria), who is cochair of the WSC scientific committee, said it was an “excellent study.”

“This study does not rely on advanced imaging (e.g., mismatch) and criteria can easily be interpreted on CT/CTA. If the study is published and all details are available this study may substantially ease endovascular therapy in the late time window,” Dr. Kiechl told this news organization.

Also commenting, Urs Fischer, MD, chairman of the department of neurology at the University Hospital Basel (Switzerland), who was not involved with MR CLEAN-LATE, said: “This is another study that has nicely shown that endovascular therapy in patients in the later time window is highly effective.”

Dr. Fischer said he was not surprised by the results. 

“I was expecting the trial to be positive,” he said. “What we can say is that endovascular therapy in patients with proximal vessel occlusion is a very effective intervention – probably one of the most important interventions in the history of medicine – and now we have another subgroup to whom we can offer this therapy. So, this is an important study that will improve the outcome of many further patients.”

Yvo Roos, MD, professor of acute neurology at University Medical Center, Amsterdam, who was a MR CLEAN-LATE investigator, agreed that the trial has the potential to increase number of patients who can be treated with endovascular therapy.

But both Dr. Roos and Dr. Fischer were not convinced that collateral assessment would replace CT perfusion as the first-line choice in selecting patients for endovascular treatment.

“We need to see what kind of patients were included in the trial and what kind of perfusion imaging characteristics they had, to see how they compare with patients selected by perfusion imaging,” Dr. Roos noted. “I think CT perfusion is here. But if the data shows that collateral score is better able to identify patients for endovascular treatment than CT perfusion, then this has the potential to change practice. But that needs to be shown.”

All patients screened for the MR CLEAN-LATE trial also received CT perfusion imaging as part of the standard imaging protocol, and many were selected for endovascular therapy directly on this basis, so would not have entered the trial. The researchers plan to analyze these results and to compare how the two approaches differ.

MR CLEAN-LATE is an investigator-driven study, funded by the Dutch Heart Foundation, the Brain Foundation Netherlands, and Medtronic. The study was designed and conducted, analyzed, and interpreted by the investigators independently of all sponsors. Dr. Olthuis reported no relevant financial relationships.

A version of this article first appeared on Medscape.com.

Patients with acute ischemic stroke presenting late at the hospital can be selected for endovascular thrombectomy by the presence of collateral flow on CT angiography (CTA), a new study shows.

The MR CLEAN-LATE trial found that patients selected for thrombectomy in this way had a greater chance of a better functional outcome than patients who did not receive endovascular therapy.

The study was presented at the 14th World Stroke Congress in Singapore by study investigator Susanne Olthuis, MD, of Maastricht (the Netherlands) University Medical Center.

Patients in the intervention group were more likely to show a benefit on the primary endpoint of modified Rankin Scale (mRS) score at 90 days with a significant common odds ratio of 1.68, a finding that received applause from attendees of the plenary WSC session at which the study was presented.

“This means that patients treated with endovascular therapy in this trial had about a 1.7 times higher chance of achieving a better functional outcome at 90 days,” Dr. Olthuis said.

“Selection based on collateral flow identifies an additional group of patients eligible for late-window endovascular therapy in addition to those eligible based on perfusion and clinical criteria,” Dr. Olthuis concluded.

“We recommend implementation of collateral selection in routine clinical practice as it is time efficient. The CTA is already available, and it involves a low-complexity assessment. The only distinction that needs to be made is whether or not there are any collaterals visible on CTA. If collaterals are absent or there is any doubt, then CT perfusion [CTP] imaging can still be used,” she added.

Co–principal investigator Wim H. van Zwam, MD, interventional radiologist at Maastricht, said in a comment:“My take-home message is that now in the late window we can select patients based on the presence of collaterals on CT angiography, which makes selection easier and faster and more widely available.

“If any collaterals are seen – and that is easily done just by looking at the CTA scan – then the patient can be selected for endovascular treatment,” Dr. van Zwam added. “We don’t need to wait for calculations of core and penumbra volumes from the CTP scan. There will also be additional patients who can benefit from endovascular therapy who do not fulfill the CTP criteria but do have visible collaterals.”

Explaining the background to the study, Dr. Olthuis noted that endovascular thrombectomy for large vessel occlusion stroke is safe and effective if performed within 6 hours and the effect then diminishes over time. In the original trial of endovascular treatment, MR CLEAN, patients with higher collateral grades had more treatment benefit, leading to the hypothesis that the assessment of collateral blood flow could help identify patients who would still benefit in the late time window.

The current MR CLEAN-LATE trial therefore set out to compare safety and efficacy of endovascular therapy in patients with acute ischemic stroke in the anterior circulation presenting within 6-24 hours from symptom onset with patients selected based on the presence of collateral flow on CTA.

At the time the trial was starting, the DAWN and DEFUSE 3 trials reported showing benefit of endovascular therapy in patients presenting in the late window who had been selected for endovascular treatment based on a combination of perfusion imaging and clinical criteria, so patients who fitted these criteria were also excluded from MR CLEAN-LATE as they would now be eligible for endovascular therapy under the latest clinical guidelines. 

But the study continued, as “we believed collateral selection may still be able to identify an additional group of patients that may benefit from endovascular therapy in the late window,” Dr. Olthuis said.

The trial randomly assigned 502 such patients with a National Institutes of Health Stroke Scale (NIHSS) score of at least 2 and with collateral flow grades of 1-3 to receive endovascular therapy (intervention) or control.

Safety data showed a slightly but nonsignificantly higher mortality rate at 90 days in the control group (30%) versus 24% in the intervention group.

The rate of symptomatic intracranial hemorrhage was higher in the intervention group (6.7%) versus 1.6% in the control group, but Dr. Olthuis pointed out that the rate of sICH in the intervention group was similar to that in the endovascular groups of the DAWN and DEFUSE 3 trials.

The primary endpoint – mRS score at 90 days – showed a shift toward better outcome in the intervention group, with an adjusted common OR of 1.68 (95% confidence interval, 1.21-2.33).

The median mRS score in the intervention group was 3 (95% CI, 2-5) versus 4 (95% CI, 2-6) in the control group.

Secondary outcomes also showed benefits for the intervention group for the endpoints of mRS score 0-1 versus 2-6 (OR, 1.63); mRS 0-2 versus 3-6 (OR 1.54); and mRS 0-3 versus 4-6 (OR, 1.74).

In addition, NIHSS score was reduced by 17% at 24 hours and by 27% by 5-7 days or discharge in the intervention group. Recanalization at 24 hours was also improved in the intervention group (81% vs. 52%) and infarct size was reduced by 32%.

Dr. Olthuis explained that collateral grade was defined as the amount of collateral flow in the affected hemisphere as a percentage of the contralateral site, with grade 0 correlating to an absence of collaterals (and these were the only patients excluded).

Grade 1 included patients with 50% or less collaterals, grade 2 more than 50%, and grade 3 excellent collaterals – around 100%. “We included grade 1, 2 and 3, and subgroup analysis suggested no treatment interactions between different collateral grades in the patients included,” she said.

Dr. van Zwam noted that there has been evidence from other studies suggesting that the presence of collateral flow could be used to select patients for late thrombectomy, but MR CLEAN-LATE is the first randomized trial to show this and provides confirmation that this strategy is valid.

“Our results show that patients can be selected with just standard CT angiography imaging and that CT perfusion is not necessary. This will make it easier and faster to select patients especially for centers in low-resource areas who do not yet have CT perfusion imaging,” he commented.

“But even in centers where CT perfusion imaging is performed, these results should mean that we do not have to wait to analyze these results before going ahead with thrombectomy. It will also give us an additional tool, as some patients do not meet the criteria on perfusion imaging but still have identifiable collaterals and thus would now qualify for endovascular thrombectomy,” he added.
 

Could collateral assessment replace CT perfusion?

Commenting on the MR CLEAN-LATE trial, Stefan Kiechl, MD, Medical University of Innsbruck (Austria), who is cochair of the WSC scientific committee, said it was an “excellent study.”

“This study does not rely on advanced imaging (e.g., mismatch) and criteria can easily be interpreted on CT/CTA. If the study is published and all details are available this study may substantially ease endovascular therapy in the late time window,” Dr. Kiechl told this news organization.

Also commenting, Urs Fischer, MD, chairman of the department of neurology at the University Hospital Basel (Switzerland), who was not involved with MR CLEAN-LATE, said: “This is another study that has nicely shown that endovascular therapy in patients in the later time window is highly effective.”

Dr. Fischer said he was not surprised by the results. 

“I was expecting the trial to be positive,” he said. “What we can say is that endovascular therapy in patients with proximal vessel occlusion is a very effective intervention – probably one of the most important interventions in the history of medicine – and now we have another subgroup to whom we can offer this therapy. So, this is an important study that will improve the outcome of many further patients.”

Yvo Roos, MD, professor of acute neurology at University Medical Center, Amsterdam, who was a MR CLEAN-LATE investigator, agreed that the trial has the potential to increase number of patients who can be treated with endovascular therapy.

But both Dr. Roos and Dr. Fischer were not convinced that collateral assessment would replace CT perfusion as the first-line choice in selecting patients for endovascular treatment.

“We need to see what kind of patients were included in the trial and what kind of perfusion imaging characteristics they had, to see how they compare with patients selected by perfusion imaging,” Dr. Roos noted. “I think CT perfusion is here. But if the data shows that collateral score is better able to identify patients for endovascular treatment than CT perfusion, then this has the potential to change practice. But that needs to be shown.”

All patients screened for the MR CLEAN-LATE trial also received CT perfusion imaging as part of the standard imaging protocol, and many were selected for endovascular therapy directly on this basis, so would not have entered the trial. The researchers plan to analyze these results and to compare how the two approaches differ.

MR CLEAN-LATE is an investigator-driven study, funded by the Dutch Heart Foundation, the Brain Foundation Netherlands, and Medtronic. The study was designed and conducted, analyzed, and interpreted by the investigators independently of all sponsors. Dr. Olthuis reported no relevant financial relationships.

A version of this article first appeared on Medscape.com.

Patients with acute ischemic stroke presenting late at the hospital can be selected for endovascular thrombectomy by the presence of collateral flow on CT angiography (CTA), a new study shows.

The MR CLEAN-LATE trial found that patients selected for thrombectomy in this way had a greater chance of a better functional outcome than patients who did not receive endovascular therapy.

The study was presented at the 14th World Stroke Congress in Singapore by study investigator Susanne Olthuis, MD, of Maastricht (the Netherlands) University Medical Center.

Patients in the intervention group were more likely to show a benefit on the primary endpoint of modified Rankin Scale (mRS) score at 90 days with a significant common odds ratio of 1.68, a finding that received applause from attendees of the plenary WSC session at which the study was presented.

“This means that patients treated with endovascular therapy in this trial had about a 1.7 times higher chance of achieving a better functional outcome at 90 days,” Dr. Olthuis said.

“Selection based on collateral flow identifies an additional group of patients eligible for late-window endovascular therapy in addition to those eligible based on perfusion and clinical criteria,” Dr. Olthuis concluded.

“We recommend implementation of collateral selection in routine clinical practice as it is time efficient. The CTA is already available, and it involves a low-complexity assessment. The only distinction that needs to be made is whether or not there are any collaterals visible on CTA. If collaterals are absent or there is any doubt, then CT perfusion [CTP] imaging can still be used,” she added.

Co–principal investigator Wim H. van Zwam, MD, interventional radiologist at Maastricht, said in a comment:“My take-home message is that now in the late window we can select patients based on the presence of collaterals on CT angiography, which makes selection easier and faster and more widely available.

“If any collaterals are seen – and that is easily done just by looking at the CTA scan – then the patient can be selected for endovascular treatment,” Dr. van Zwam added. “We don’t need to wait for calculations of core and penumbra volumes from the CTP scan. There will also be additional patients who can benefit from endovascular therapy who do not fulfill the CTP criteria but do have visible collaterals.”

Explaining the background to the study, Dr. Olthuis noted that endovascular thrombectomy for large vessel occlusion stroke is safe and effective if performed within 6 hours and the effect then diminishes over time. In the original trial of endovascular treatment, MR CLEAN, patients with higher collateral grades had more treatment benefit, leading to the hypothesis that the assessment of collateral blood flow could help identify patients who would still benefit in the late time window.

The current MR CLEAN-LATE trial therefore set out to compare safety and efficacy of endovascular therapy in patients with acute ischemic stroke in the anterior circulation presenting within 6-24 hours from symptom onset with patients selected based on the presence of collateral flow on CTA.

At the time the trial was starting, the DAWN and DEFUSE 3 trials reported showing benefit of endovascular therapy in patients presenting in the late window who had been selected for endovascular treatment based on a combination of perfusion imaging and clinical criteria, so patients who fitted these criteria were also excluded from MR CLEAN-LATE as they would now be eligible for endovascular therapy under the latest clinical guidelines. 

But the study continued, as “we believed collateral selection may still be able to identify an additional group of patients that may benefit from endovascular therapy in the late window,” Dr. Olthuis said.

The trial randomly assigned 502 such patients with a National Institutes of Health Stroke Scale (NIHSS) score of at least 2 and with collateral flow grades of 1-3 to receive endovascular therapy (intervention) or control.

Safety data showed a slightly but nonsignificantly higher mortality rate at 90 days in the control group (30%) versus 24% in the intervention group.

The rate of symptomatic intracranial hemorrhage was higher in the intervention group (6.7%) versus 1.6% in the control group, but Dr. Olthuis pointed out that the rate of sICH in the intervention group was similar to that in the endovascular groups of the DAWN and DEFUSE 3 trials.

The primary endpoint – mRS score at 90 days – showed a shift toward better outcome in the intervention group, with an adjusted common OR of 1.68 (95% confidence interval, 1.21-2.33).

The median mRS score in the intervention group was 3 (95% CI, 2-5) versus 4 (95% CI, 2-6) in the control group.

Secondary outcomes also showed benefits for the intervention group for the endpoints of mRS score 0-1 versus 2-6 (OR, 1.63); mRS 0-2 versus 3-6 (OR 1.54); and mRS 0-3 versus 4-6 (OR, 1.74).

In addition, NIHSS score was reduced by 17% at 24 hours and by 27% by 5-7 days or discharge in the intervention group. Recanalization at 24 hours was also improved in the intervention group (81% vs. 52%) and infarct size was reduced by 32%.

Dr. Olthuis explained that collateral grade was defined as the amount of collateral flow in the affected hemisphere as a percentage of the contralateral site, with grade 0 correlating to an absence of collaterals (and these were the only patients excluded).

Grade 1 included patients with 50% or less collaterals, grade 2 more than 50%, and grade 3 excellent collaterals – around 100%. “We included grade 1, 2 and 3, and subgroup analysis suggested no treatment interactions between different collateral grades in the patients included,” she said.

Dr. van Zwam noted that there has been evidence from other studies suggesting that the presence of collateral flow could be used to select patients for late thrombectomy, but MR CLEAN-LATE is the first randomized trial to show this and provides confirmation that this strategy is valid.

“Our results show that patients can be selected with just standard CT angiography imaging and that CT perfusion is not necessary. This will make it easier and faster to select patients especially for centers in low-resource areas who do not yet have CT perfusion imaging,” he commented.

“But even in centers where CT perfusion imaging is performed, these results should mean that we do not have to wait to analyze these results before going ahead with thrombectomy. It will also give us an additional tool, as some patients do not meet the criteria on perfusion imaging but still have identifiable collaterals and thus would now qualify for endovascular thrombectomy,” he added.
 

Could collateral assessment replace CT perfusion?

Commenting on the MR CLEAN-LATE trial, Stefan Kiechl, MD, Medical University of Innsbruck (Austria), who is cochair of the WSC scientific committee, said it was an “excellent study.”

“This study does not rely on advanced imaging (e.g., mismatch) and criteria can easily be interpreted on CT/CTA. If the study is published and all details are available this study may substantially ease endovascular therapy in the late time window,” Dr. Kiechl told this news organization.

Also commenting, Urs Fischer, MD, chairman of the department of neurology at the University Hospital Basel (Switzerland), who was not involved with MR CLEAN-LATE, said: “This is another study that has nicely shown that endovascular therapy in patients in the later time window is highly effective.”

Dr. Fischer said he was not surprised by the results. 

“I was expecting the trial to be positive,” he said. “What we can say is that endovascular therapy in patients with proximal vessel occlusion is a very effective intervention – probably one of the most important interventions in the history of medicine – and now we have another subgroup to whom we can offer this therapy. So, this is an important study that will improve the outcome of many further patients.”

Yvo Roos, MD, professor of acute neurology at University Medical Center, Amsterdam, who was a MR CLEAN-LATE investigator, agreed that the trial has the potential to increase number of patients who can be treated with endovascular therapy.

But both Dr. Roos and Dr. Fischer were not convinced that collateral assessment would replace CT perfusion as the first-line choice in selecting patients for endovascular treatment.

“We need to see what kind of patients were included in the trial and what kind of perfusion imaging characteristics they had, to see how they compare with patients selected by perfusion imaging,” Dr. Roos noted. “I think CT perfusion is here. But if the data shows that collateral score is better able to identify patients for endovascular treatment than CT perfusion, then this has the potential to change practice. But that needs to be shown.”

All patients screened for the MR CLEAN-LATE trial also received CT perfusion imaging as part of the standard imaging protocol, and many were selected for endovascular therapy directly on this basis, so would not have entered the trial. The researchers plan to analyze these results and to compare how the two approaches differ.

MR CLEAN-LATE is an investigator-driven study, funded by the Dutch Heart Foundation, the Brain Foundation Netherlands, and Medtronic. The study was designed and conducted, analyzed, and interpreted by the investigators independently of all sponsors. Dr. Olthuis reported no relevant financial relationships.

A version of this article first appeared on Medscape.com.

Apixaban offers greater protection than rivaroxaban against ischemic stroke, systemic embolism, and bleeding in patients with both atrial fibrillation (AFib) and valvular heart disease (VHD), a new study finds.

Compared with rivaroxaban, apixaban cut risks nearly in half, suggesting that clinicians should consider these new data when choosing an anticoagulant, reported lead author Ghadeer K. Dawwas, PhD, of the University of Pennsylvania, Philadelphia, and colleagues.

In the new retrospective study involving almost 20,000 patients, Dr. Dawwas and her colleagues “emulated a target trial” using private insurance claims from Optum’s deidentified Clinformatics Data Mart Database. The cohort was narrowed from a screened population of 58,210 patients with concurrent AFib and VHD to 9,947 new apixaban users who could be closely matched with 9,947 new rivaroxaban users. Covariates included provider specialty, type of VHD, demographic characteristics, measures of health care use, baseline use of medications, and baseline comorbidities.

The primary effectiveness outcome was a composite of systemic embolism and ischemic stroke, while the primary safety outcome was a composite of intracranial or gastrointestinal bleeding.

“Although several ongoing trials aim to compare apixaban with warfarin in patients with AFib and VHD, none of these trials will directly compare apixaban and rivaroxaban,” the investigators wrote. Their report is in Annals of Internal Medicine.

Dr. Dawwas and colleagues previously showed that direct oral anticoagulants (DOACs) were safer and more effective than warfarin in the same patient population. Comparing apixaban and rivaroxaban – the two most common DOACs – was the next logical step, Dr. Dawwas said in an interview.
 

Study results

Compared with rivaroxaban, patients who received apixaban had a 43% reduced risk of stroke or embolism (hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.40-0.80). Apixaban’s ability to protect against bleeding appeared even more pronounced, with a 49% reduced risk over rivaroxaban (HR, 0.51; 95% CI, 0.41-0.62).

Comparing the two agents on an absolute basis, apixaban reduced risk of embolism or stroke by 0.2% within the first 6 months of treatment initiation, and 1.1% within the first year of initiation. At the same time points, absolute risk reductions for bleeding were 1.2% and 1.9%, respectively.

The investigators noted that their results held consistent in an alternative analysis that considered separate types of VHD.

“Based on the results from our analysis, we showed that apixaban is effective and safe in patients with atrial fibrillation and valvular heart diseases,” Dr. Dawwas said.
 

Head-to-head trial needed to change practice

Christopher M. Bianco, DO, associate professor of medicine at West Virginia University Heart and Vascular Institute, Morgantown, said the findings “add to the growing body of literature,” but “a head-to-head trial would be necessary to make a definitive change to clinical practice.”

Dr. Bianco, who recently conducted a retrospective analysis of apixaban and rivaroxaban that found no difference in safety and efficacy among a different patient population, said these kinds of studies are helpful in generating hypotheses, but they can’t account for all relevant clinical factors.

“There are just so many things that go into the decision-making process of [prescribing] apixaban and rivaroxaban,” he said. “Even though [Dr. Dawwas and colleagues] used propensity matching, you’re never going to be able to sort that out with a retrospective analysis.”

Specifically, Dr. Bianco noted that the findings did not include dose data. This is a key gap, he said, considering how often real-world datasets have shown that providers underdose DOACs for a number of unaccountable reasons, and how frequently patients exhibit poor adherence.

The study also lacked detail concerning the degree of renal dysfunction, which can determine drug eligibility, Dr. Bianco said. Furthermore, attempts to stratify patients based on thrombosis and bleeding risk were likely “insufficient,” he added.

Dr. Bianco also cautioned that the investigators defined valvular heart disease as any valve-related disease of any severity. In contrast, previous studies have generally restricted valvular heart disease to patients with mitral stenosis or prosthetic valves.

“This is definitely not the traditional definition of valvular heart disease, so the title is a little bit misleading in that sense, although they certainly do disclose that in the methods,” Dr. Bianco said.

On a more positive note, he highlighted the size of the patient population, and the real-world data, which included many patients who would be excluded from clinical trials.

More broadly, the study helps drive research forward, Dr. Bianco concluded; namely, by attracting financial support for a more powerful head-to-head trial that drug makers are unlikely to fund due to inherent market risk.

This study was supported by the National Institutes of Health. The investigators disclosed additional relationships with Takeda, Spark, Sanofi, and others. Dr. Bianco disclosed no conflicts of interest.

Apixaban offers greater protection than rivaroxaban against ischemic stroke, systemic embolism, and bleeding in patients with both atrial fibrillation (AFib) and valvular heart disease (VHD), a new study finds.

Compared with rivaroxaban, apixaban cut risks nearly in half, suggesting that clinicians should consider these new data when choosing an anticoagulant, reported lead author Ghadeer K. Dawwas, PhD, of the University of Pennsylvania, Philadelphia, and colleagues.

In the new retrospective study involving almost 20,000 patients, Dr. Dawwas and her colleagues “emulated a target trial” using private insurance claims from Optum’s deidentified Clinformatics Data Mart Database. The cohort was narrowed from a screened population of 58,210 patients with concurrent AFib and VHD to 9,947 new apixaban users who could be closely matched with 9,947 new rivaroxaban users. Covariates included provider specialty, type of VHD, demographic characteristics, measures of health care use, baseline use of medications, and baseline comorbidities.

The primary effectiveness outcome was a composite of systemic embolism and ischemic stroke, while the primary safety outcome was a composite of intracranial or gastrointestinal bleeding.

“Although several ongoing trials aim to compare apixaban with warfarin in patients with AFib and VHD, none of these trials will directly compare apixaban and rivaroxaban,” the investigators wrote. Their report is in Annals of Internal Medicine.

Dr. Dawwas and colleagues previously showed that direct oral anticoagulants (DOACs) were safer and more effective than warfarin in the same patient population. Comparing apixaban and rivaroxaban – the two most common DOACs – was the next logical step, Dr. Dawwas said in an interview.
 

Study results

Compared with rivaroxaban, patients who received apixaban had a 43% reduced risk of stroke or embolism (hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.40-0.80). Apixaban’s ability to protect against bleeding appeared even more pronounced, with a 49% reduced risk over rivaroxaban (HR, 0.51; 95% CI, 0.41-0.62).

Comparing the two agents on an absolute basis, apixaban reduced risk of embolism or stroke by 0.2% within the first 6 months of treatment initiation, and 1.1% within the first year of initiation. At the same time points, absolute risk reductions for bleeding were 1.2% and 1.9%, respectively.

The investigators noted that their results held consistent in an alternative analysis that considered separate types of VHD.

“Based on the results from our analysis, we showed that apixaban is effective and safe in patients with atrial fibrillation and valvular heart diseases,” Dr. Dawwas said.
 

Head-to-head trial needed to change practice

Christopher M. Bianco, DO, associate professor of medicine at West Virginia University Heart and Vascular Institute, Morgantown, said the findings “add to the growing body of literature,” but “a head-to-head trial would be necessary to make a definitive change to clinical practice.”

Dr. Bianco, who recently conducted a retrospective analysis of apixaban and rivaroxaban that found no difference in safety and efficacy among a different patient population, said these kinds of studies are helpful in generating hypotheses, but they can’t account for all relevant clinical factors.

“There are just so many things that go into the decision-making process of [prescribing] apixaban and rivaroxaban,” he said. “Even though [Dr. Dawwas and colleagues] used propensity matching, you’re never going to be able to sort that out with a retrospective analysis.”

Specifically, Dr. Bianco noted that the findings did not include dose data. This is a key gap, he said, considering how often real-world datasets have shown that providers underdose DOACs for a number of unaccountable reasons, and how frequently patients exhibit poor adherence.

The study also lacked detail concerning the degree of renal dysfunction, which can determine drug eligibility, Dr. Bianco said. Furthermore, attempts to stratify patients based on thrombosis and bleeding risk were likely “insufficient,” he added.

Dr. Bianco also cautioned that the investigators defined valvular heart disease as any valve-related disease of any severity. In contrast, previous studies have generally restricted valvular heart disease to patients with mitral stenosis or prosthetic valves.

“This is definitely not the traditional definition of valvular heart disease, so the title is a little bit misleading in that sense, although they certainly do disclose that in the methods,” Dr. Bianco said.

On a more positive note, he highlighted the size of the patient population, and the real-world data, which included many patients who would be excluded from clinical trials.

More broadly, the study helps drive research forward, Dr. Bianco concluded; namely, by attracting financial support for a more powerful head-to-head trial that drug makers are unlikely to fund due to inherent market risk.

This study was supported by the National Institutes of Health. The investigators disclosed additional relationships with Takeda, Spark, Sanofi, and others. Dr. Bianco disclosed no conflicts of interest.

Apixaban offers greater protection than rivaroxaban against ischemic stroke, systemic embolism, and bleeding in patients with both atrial fibrillation (AFib) and valvular heart disease (VHD), a new study finds.

Compared with rivaroxaban, apixaban cut risks nearly in half, suggesting that clinicians should consider these new data when choosing an anticoagulant, reported lead author Ghadeer K. Dawwas, PhD, of the University of Pennsylvania, Philadelphia, and colleagues.

In the new retrospective study involving almost 20,000 patients, Dr. Dawwas and her colleagues “emulated a target trial” using private insurance claims from Optum’s deidentified Clinformatics Data Mart Database. The cohort was narrowed from a screened population of 58,210 patients with concurrent AFib and VHD to 9,947 new apixaban users who could be closely matched with 9,947 new rivaroxaban users. Covariates included provider specialty, type of VHD, demographic characteristics, measures of health care use, baseline use of medications, and baseline comorbidities.

The primary effectiveness outcome was a composite of systemic embolism and ischemic stroke, while the primary safety outcome was a composite of intracranial or gastrointestinal bleeding.

“Although several ongoing trials aim to compare apixaban with warfarin in patients with AFib and VHD, none of these trials will directly compare apixaban and rivaroxaban,” the investigators wrote. Their report is in Annals of Internal Medicine.

Dr. Dawwas and colleagues previously showed that direct oral anticoagulants (DOACs) were safer and more effective than warfarin in the same patient population. Comparing apixaban and rivaroxaban – the two most common DOACs – was the next logical step, Dr. Dawwas said in an interview.
 

Study results

Compared with rivaroxaban, patients who received apixaban had a 43% reduced risk of stroke or embolism (hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.40-0.80). Apixaban’s ability to protect against bleeding appeared even more pronounced, with a 49% reduced risk over rivaroxaban (HR, 0.51; 95% CI, 0.41-0.62).

Comparing the two agents on an absolute basis, apixaban reduced risk of embolism or stroke by 0.2% within the first 6 months of treatment initiation, and 1.1% within the first year of initiation. At the same time points, absolute risk reductions for bleeding were 1.2% and 1.9%, respectively.

The investigators noted that their results held consistent in an alternative analysis that considered separate types of VHD.

“Based on the results from our analysis, we showed that apixaban is effective and safe in patients with atrial fibrillation and valvular heart diseases,” Dr. Dawwas said.
 

Head-to-head trial needed to change practice

Christopher M. Bianco, DO, associate professor of medicine at West Virginia University Heart and Vascular Institute, Morgantown, said the findings “add to the growing body of literature,” but “a head-to-head trial would be necessary to make a definitive change to clinical practice.”

Dr. Bianco, who recently conducted a retrospective analysis of apixaban and rivaroxaban that found no difference in safety and efficacy among a different patient population, said these kinds of studies are helpful in generating hypotheses, but they can’t account for all relevant clinical factors.

“There are just so many things that go into the decision-making process of [prescribing] apixaban and rivaroxaban,” he said. “Even though [Dr. Dawwas and colleagues] used propensity matching, you’re never going to be able to sort that out with a retrospective analysis.”

Specifically, Dr. Bianco noted that the findings did not include dose data. This is a key gap, he said, considering how often real-world datasets have shown that providers underdose DOACs for a number of unaccountable reasons, and how frequently patients exhibit poor adherence.

The study also lacked detail concerning the degree of renal dysfunction, which can determine drug eligibility, Dr. Bianco said. Furthermore, attempts to stratify patients based on thrombosis and bleeding risk were likely “insufficient,” he added.

Dr. Bianco also cautioned that the investigators defined valvular heart disease as any valve-related disease of any severity. In contrast, previous studies have generally restricted valvular heart disease to patients with mitral stenosis or prosthetic valves.

“This is definitely not the traditional definition of valvular heart disease, so the title is a little bit misleading in that sense, although they certainly do disclose that in the methods,” Dr. Bianco said.

On a more positive note, he highlighted the size of the patient population, and the real-world data, which included many patients who would be excluded from clinical trials.

More broadly, the study helps drive research forward, Dr. Bianco concluded; namely, by attracting financial support for a more powerful head-to-head trial that drug makers are unlikely to fund due to inherent market risk.

This study was supported by the National Institutes of Health. The investigators disclosed additional relationships with Takeda, Spark, Sanofi, and others. Dr. Bianco disclosed no conflicts of interest.

Nirmatrelvir/ritonavir (Paxlovid) has been a game changer for high-risk patients with early COVID-19 symptoms but has significant interactions with commonly used cardiovascular medications, a new paper cautions.

COVID-19 patients with cardiovascular disease (CVD) or risk factors such as diabetes, hypertension, and chronic kidney disease are at high risk of severe disease and account for the lion’s share of those receiving Paxlovid. Data from the initial EPIC-HR trial and recent real-world data also suggest they’re among the most likely to benefit from the oral antiviral, regardless of their COVID-19 vaccination status.

ClaudioVentrella/Thinkstock

“But at the same time, it unfortunately interacts with many very commonly prescribed cardiovascular medications and with many of them in a very clinically meaningful way, which may lead to serious adverse consequences,” senior author Sarju Ganatra, MD, said in an interview. “So, while it’s being prescribed with a good intention to help these people, we may actually end up doing more harm than good.

“We don’t want to deter people from getting their necessary COVID-19 treatment, which is excellent for the most part these days as an outpatient,” he added. “So, we felt the need to make a comprehensive list of cardiac medications and level of interactions with Paxlovid and also to help the clinicians and prescribers at the point of care to make the clinical decision of what modifications they may need to do.”

The paper, published online in the Journal of the American College of Cardiology, details drug-drug interactions with some 80 CV medications including statins, antihypertensive agents, heart failure therapies, and antiplatelet/anticoagulants.

It also includes a color-coded figure denoting whether a drug is safe to coadminister with Paxlovid, may potentially interact and require a dose adjustment or temporary discontinuation, or is contraindicated.

Among the commonly used blood thinners, for example, the paper notes that Paxlovid significantly increases drug levels of the direct oral anticoagulants (DOACs) apixaban, rivaroxaban, edoxaban, and dabigatran and, thus, increases the risk of bleeding.

“It can still be administered, if it’s necessary, but the dose of the DOAC either needs to be reduced or held depending on what they are getting it for, whether they’re getting it for pulmonary embolism or atrial fibrillation, and we adjust for all those things in the table in the paper,” said Dr. Ganatra, from Lahey Hospital and Medical Center, Burlington, Mass.

When the DOAC can’t be interrupted or dose adjusted, however, Paxlovid should not be given, the experts said. The antiviral is safe to use with enoxaparin, a low-molecular-weight heparin, but can increase or decrease levels of warfarin and should be used with close international normalized ratio monitoring.

For patients on antiplatelet agents, clinicians are advised to avoid prescribing nirmatrelvir/ritonavir to those on ticagrelor or clopidogrel unless the agents can be replaced by prasugrel.

Ritonavir – an inhibitor of cytochrome P 450 enzymes, particularly CYP3A4 – poses an increased risk of bleeding when given with ticagrelor, a CYP3A4 substrate, and decreases the active metabolite of clopidogrel, cutting its platelet inhibition by 20%. Although there’s a twofold decrease in the maximum concentration of prasugrel in patients on ritonavir, this does not affect its antiplatelet activity, the paper explains.

Among the lipid-lowering agents, experts suggested temporarily withholding atorvastatin, rosuvastatin, simvastatin, and lovastatin because of an increased risk for myopathy and liver toxicity but say that other statins, fibrates, ezetimibe, and the proprotein convertase subtilisin/kexin type 9 inhibitors evolocumab and alirocumab are safe to coadminister with Paxlovid.

While statins typically leave the body within hours, most of the antiarrhythmic drugs, except for sotalol, are not safe to give with Paxlovid, Dr. Ganatra said. It’s technically not feasible to hold these drugs because most have long half-lives, reaching about 100 days, for example, for amiodarone.

“It’s going to hang around in your system for a long time, so you don’t want to be falsely reassured that you’re holding the drug and it’s going to be fine to go back slowly,” he said. “You need to look for alternative therapies in those scenarios for COVID-19 treatment, which could be other antivirals, or a monoclonal antibody individualized to the patient’s risk.”

Although there’s limited clinical information regarding interaction-related adverse events with Paxlovid, the team used pharmacokinetics and pharmacodynamics data to provide the guidance. Serious adverse events are also well documented for ritonavir, which has been prescribed for years to treat HIV, Dr. Ganatra noted.

The Infectious Disease Society of America also published guidance on the management of potential drug interactions with Paxlovid in May and, earlier in October, the Food and Drug Administration updated its Paxlovid patient eligibility screening checklist.

Still, most prescribers are actually primary care physicians and even pharmacists, who may not be completely attuned, said Dr. Ganatra, who noted that some centers have started programs to help connect primary care physicians with their cardiology colleagues to check on CV drugs in their COVID-19 patients.

“We need to be thinking more broadly and at a system level where the hospital or health care system leverages the electronic health record systems,” he said. “Most of them are sophisticated enough to incorporate simple drug-drug interaction information, so if you try to prescribe someone Paxlovid and it’s a heart transplant patient who is on immunosuppressive therapy or a patient on a blood thinner, then it should give you a warning ... or at least give them a link to our paper or other valuable resources.

“If someone is on a blood thinner and the blood thinner level goes up by ninefold, we can only imagine what we would be dealing with,” Dr. Ganatra said. “So, these interactions should be taken very seriously and I think it’s worth the time and investment.”

The authors reported no relevant financial relationships.

A version of this article first appeared on Medscape.com.

Nirmatrelvir/ritonavir (Paxlovid) has been a game changer for high-risk patients with early COVID-19 symptoms but has significant interactions with commonly used cardiovascular medications, a new paper cautions.

COVID-19 patients with cardiovascular disease (CVD) or risk factors such as diabetes, hypertension, and chronic kidney disease are at high risk of severe disease and account for the lion’s share of those receiving Paxlovid. Data from the initial EPIC-HR trial and recent real-world data also suggest they’re among the most likely to benefit from the oral antiviral, regardless of their COVID-19 vaccination status.

ClaudioVentrella/Thinkstock

“But at the same time, it unfortunately interacts with many very commonly prescribed cardiovascular medications and with many of them in a very clinically meaningful way, which may lead to serious adverse consequences,” senior author Sarju Ganatra, MD, said in an interview. “So, while it’s being prescribed with a good intention to help these people, we may actually end up doing more harm than good.

“We don’t want to deter people from getting their necessary COVID-19 treatment, which is excellent for the most part these days as an outpatient,” he added. “So, we felt the need to make a comprehensive list of cardiac medications and level of interactions with Paxlovid and also to help the clinicians and prescribers at the point of care to make the clinical decision of what modifications they may need to do.”

The paper, published online in the Journal of the American College of Cardiology, details drug-drug interactions with some 80 CV medications including statins, antihypertensive agents, heart failure therapies, and antiplatelet/anticoagulants.

It also includes a color-coded figure denoting whether a drug is safe to coadminister with Paxlovid, may potentially interact and require a dose adjustment or temporary discontinuation, or is contraindicated.

Among the commonly used blood thinners, for example, the paper notes that Paxlovid significantly increases drug levels of the direct oral anticoagulants (DOACs) apixaban, rivaroxaban, edoxaban, and dabigatran and, thus, increases the risk of bleeding.

“It can still be administered, if it’s necessary, but the dose of the DOAC either needs to be reduced or held depending on what they are getting it for, whether they’re getting it for pulmonary embolism or atrial fibrillation, and we adjust for all those things in the table in the paper,” said Dr. Ganatra, from Lahey Hospital and Medical Center, Burlington, Mass.

When the DOAC can’t be interrupted or dose adjusted, however, Paxlovid should not be given, the experts said. The antiviral is safe to use with enoxaparin, a low-molecular-weight heparin, but can increase or decrease levels of warfarin and should be used with close international normalized ratio monitoring.

For patients on antiplatelet agents, clinicians are advised to avoid prescribing nirmatrelvir/ritonavir to those on ticagrelor or clopidogrel unless the agents can be replaced by prasugrel.

Ritonavir – an inhibitor of cytochrome P 450 enzymes, particularly CYP3A4 – poses an increased risk of bleeding when given with ticagrelor, a CYP3A4 substrate, and decreases the active metabolite of clopidogrel, cutting its platelet inhibition by 20%. Although there’s a twofold decrease in the maximum concentration of prasugrel in patients on ritonavir, this does not affect its antiplatelet activity, the paper explains.

Among the lipid-lowering agents, experts suggested temporarily withholding atorvastatin, rosuvastatin, simvastatin, and lovastatin because of an increased risk for myopathy and liver toxicity but say that other statins, fibrates, ezetimibe, and the proprotein convertase subtilisin/kexin type 9 inhibitors evolocumab and alirocumab are safe to coadminister with Paxlovid.

While statins typically leave the body within hours, most of the antiarrhythmic drugs, except for sotalol, are not safe to give with Paxlovid, Dr. Ganatra said. It’s technically not feasible to hold these drugs because most have long half-lives, reaching about 100 days, for example, for amiodarone.

“It’s going to hang around in your system for a long time, so you don’t want to be falsely reassured that you’re holding the drug and it’s going to be fine to go back slowly,” he said. “You need to look for alternative therapies in those scenarios for COVID-19 treatment, which could be other antivirals, or a monoclonal antibody individualized to the patient’s risk.”

Although there’s limited clinical information regarding interaction-related adverse events with Paxlovid, the team used pharmacokinetics and pharmacodynamics data to provide the guidance. Serious adverse events are also well documented for ritonavir, which has been prescribed for years to treat HIV, Dr. Ganatra noted.

The Infectious Disease Society of America also published guidance on the management of potential drug interactions with Paxlovid in May and, earlier in October, the Food and Drug Administration updated its Paxlovid patient eligibility screening checklist.

Still, most prescribers are actually primary care physicians and even pharmacists, who may not be completely attuned, said Dr. Ganatra, who noted that some centers have started programs to help connect primary care physicians with their cardiology colleagues to check on CV drugs in their COVID-19 patients.

“We need to be thinking more broadly and at a system level where the hospital or health care system leverages the electronic health record systems,” he said. “Most of them are sophisticated enough to incorporate simple drug-drug interaction information, so if you try to prescribe someone Paxlovid and it’s a heart transplant patient who is on immunosuppressive therapy or a patient on a blood thinner, then it should give you a warning ... or at least give them a link to our paper or other valuable resources.

“If someone is on a blood thinner and the blood thinner level goes up by ninefold, we can only imagine what we would be dealing with,” Dr. Ganatra said. “So, these interactions should be taken very seriously and I think it’s worth the time and investment.”

The authors reported no relevant financial relationships.

A version of this article first appeared on Medscape.com.

Nirmatrelvir/ritonavir (Paxlovid) has been a game changer for high-risk patients with early COVID-19 symptoms but has significant interactions with commonly used cardiovascular medications, a new paper cautions.

COVID-19 patients with cardiovascular disease (CVD) or risk factors such as diabetes, hypertension, and chronic kidney disease are at high risk of severe disease and account for the lion’s share of those receiving Paxlovid. Data from the initial EPIC-HR trial and recent real-world data also suggest they’re among the most likely to benefit from the oral antiviral, regardless of their COVID-19 vaccination status.

ClaudioVentrella/Thinkstock

“But at the same time, it unfortunately interacts with many very commonly prescribed cardiovascular medications and with many of them in a very clinically meaningful way, which may lead to serious adverse consequences,” senior author Sarju Ganatra, MD, said in an interview. “So, while it’s being prescribed with a good intention to help these people, we may actually end up doing more harm than good.

“We don’t want to deter people from getting their necessary COVID-19 treatment, which is excellent for the most part these days as an outpatient,” he added. “So, we felt the need to make a comprehensive list of cardiac medications and level of interactions with Paxlovid and also to help the clinicians and prescribers at the point of care to make the clinical decision of what modifications they may need to do.”

The paper, published online in the Journal of the American College of Cardiology, details drug-drug interactions with some 80 CV medications including statins, antihypertensive agents, heart failure therapies, and antiplatelet/anticoagulants.

It also includes a color-coded figure denoting whether a drug is safe to coadminister with Paxlovid, may potentially interact and require a dose adjustment or temporary discontinuation, or is contraindicated.

Among the commonly used blood thinners, for example, the paper notes that Paxlovid significantly increases drug levels of the direct oral anticoagulants (DOACs) apixaban, rivaroxaban, edoxaban, and dabigatran and, thus, increases the risk of bleeding.

“It can still be administered, if it’s necessary, but the dose of the DOAC either needs to be reduced or held depending on what they are getting it for, whether they’re getting it for pulmonary embolism or atrial fibrillation, and we adjust for all those things in the table in the paper,” said Dr. Ganatra, from Lahey Hospital and Medical Center, Burlington, Mass.

When the DOAC can’t be interrupted or dose adjusted, however, Paxlovid should not be given, the experts said. The antiviral is safe to use with enoxaparin, a low-molecular-weight heparin, but can increase or decrease levels of warfarin and should be used with close international normalized ratio monitoring.

For patients on antiplatelet agents, clinicians are advised to avoid prescribing nirmatrelvir/ritonavir to those on ticagrelor or clopidogrel unless the agents can be replaced by prasugrel.

Ritonavir – an inhibitor of cytochrome P 450 enzymes, particularly CYP3A4 – poses an increased risk of bleeding when given with ticagrelor, a CYP3A4 substrate, and decreases the active metabolite of clopidogrel, cutting its platelet inhibition by 20%. Although there’s a twofold decrease in the maximum concentration of prasugrel in patients on ritonavir, this does not affect its antiplatelet activity, the paper explains.

Among the lipid-lowering agents, experts suggested temporarily withholding atorvastatin, rosuvastatin, simvastatin, and lovastatin because of an increased risk for myopathy and liver toxicity but say that other statins, fibrates, ezetimibe, and the proprotein convertase subtilisin/kexin type 9 inhibitors evolocumab and alirocumab are safe to coadminister with Paxlovid.

While statins typically leave the body within hours, most of the antiarrhythmic drugs, except for sotalol, are not safe to give with Paxlovid, Dr. Ganatra said. It’s technically not feasible to hold these drugs because most have long half-lives, reaching about 100 days, for example, for amiodarone.

“It’s going to hang around in your system for a long time, so you don’t want to be falsely reassured that you’re holding the drug and it’s going to be fine to go back slowly,” he said. “You need to look for alternative therapies in those scenarios for COVID-19 treatment, which could be other antivirals, or a monoclonal antibody individualized to the patient’s risk.”

Although there’s limited clinical information regarding interaction-related adverse events with Paxlovid, the team used pharmacokinetics and pharmacodynamics data to provide the guidance. Serious adverse events are also well documented for ritonavir, which has been prescribed for years to treat HIV, Dr. Ganatra noted.

The Infectious Disease Society of America also published guidance on the management of potential drug interactions with Paxlovid in May and, earlier in October, the Food and Drug Administration updated its Paxlovid patient eligibility screening checklist.

Still, most prescribers are actually primary care physicians and even pharmacists, who may not be completely attuned, said Dr. Ganatra, who noted that some centers have started programs to help connect primary care physicians with their cardiology colleagues to check on CV drugs in their COVID-19 patients.

“We need to be thinking more broadly and at a system level where the hospital or health care system leverages the electronic health record systems,” he said. “Most of them are sophisticated enough to incorporate simple drug-drug interaction information, so if you try to prescribe someone Paxlovid and it’s a heart transplant patient who is on immunosuppressive therapy or a patient on a blood thinner, then it should give you a warning ... or at least give them a link to our paper or other valuable resources.

“If someone is on a blood thinner and the blood thinner level goes up by ninefold, we can only imagine what we would be dealing with,” Dr. Ganatra said. “So, these interactions should be taken very seriously and I think it’s worth the time and investment.”

The authors reported no relevant financial relationships.

A version of this article first appeared on Medscape.com.

The Amplatzer Amulet (Abbott) and first-generation Watchman 2.5 (Boston Scientific) devices provide relatively comparable results out to 3 years after left atrial appendage occlusion (LAAO), longer follow-up from the Amplatzer Amulet Left Atrial Appendage Occluder Versus Watchman Device for Stroke Prophylaxis (Amulet IDE) trial shows.

“The dual-seal Amplatzer Amulet left atrial appendage occluder continued to demonstrate safety and effectiveness through 3 years,” principal investigator Dhanunjaya Lakkireddy, MD, said in a late-breaking session at the recent Transcatheter Cardiovascular Therapeutics annual meeting.

Preliminary results, reported last year, showed that procedural complications were higher with the Amplatzer but that it provided superior closure of the left atrial appendage (LAA) at 45 days and was noninferior with respect to safety at 12 months and efficacy at 18 months.

Amulet IDE is the largest head-to-head comparison of the two devices, enrolling 1,878 high-risk patients with nonvalvular atrial fibrillation undergoing LAA closure to reduce the risk of stroke.

Three-year follow-up was higher with the Amulet device than with the Watchman, at 721 vs. 659 patients, driven by increased deaths (85 vs. 63) and withdrawals (50 vs. 23) in the Watchman group within 18 months, noted Dr. Lakkireddy, Kansas City Heart Rhythm Institute and Research Foundation, Overland Park, Kan.

Use of oral anticoagulation was higher in the Watchman group at 6 months (2.8% vs. 4.7%; P = .04), 18 months (3.1% vs. 5.6%; P = .01), and 3 years (3.7% vs. 7.3%; P < .01).

This was primarily driven by more late device-related thrombus (DRT) after 6 months with the Watchman device than with the Amulet occluder (23 vs. 10). “Perhaps the dual-closure mechanism of the Amulet explains this fundamental difference, where you have a nice smooth disc that covers the ostium,” he posited.

At 3 years, rates of cardiovascular death trended lower with Amulet than with Watchman (6.6% vs. 8.5%; P = .14), as did all-cause deaths (14.6% vs. 17.9%; P = .07).

Most cardiovascular deaths in the Amulet group were not preceded by a device factor, whereas DRT (1 vs. 4) and peridevice leak 3 mm or more (5 vs. 15) frequently preceded these deaths in the Watchman group, Dr. Lakkireddy observed. No pericardial effusion-related deaths occurred in either group.

Major bleeding, however, trended higher for the Amulet, at 16.1%, compared with 14.7% for the Watchman (P = .46). Ischemic stroke and systemic embolic rates also trended higher for Amulet, at 5%, and 4.6% for Watchman.

The protocol recommended aspirin only for both groups after 6 months. None of the 29 Amulet and 3 of the 29 Watchman patients with an ischemic stroke were on oral anticoagulation at the time of the stroke.

Device factors, however, frequently preceded ischemic strokes in the Watchman group, Dr. Lakkireddy said. DRT occurred in 1 patient with Amulet and 2 patients with Watchman and peridevice leak in 3 with Amulet and 15 with Watchman. “Again, the peridevice leak issue really stands out as an important factor,” he said at the meeting, which was sponsored by the Cardiovascular Research Foundation.

Based on “data from the large trials, it’s clearly evident that the presence of peridevice leak significantly raises the risk of stroke in follow-up,” he said. “So, attention has to be paid to the choice of the device and how we can mitigate the risk of peridevice leaks in these patients.”

The composite of stroke, systemic embolism, and cardiovascular death occurred in 11.1% of patients with Amulet and 12.7% with Watchman (P = .31).

A version of this article first appeared on Medscape.com.

The Amplatzer Amulet (Abbott) and first-generation Watchman 2.5 (Boston Scientific) devices provide relatively comparable results out to 3 years after left atrial appendage occlusion (LAAO), longer follow-up from the Amplatzer Amulet Left Atrial Appendage Occluder Versus Watchman Device for Stroke Prophylaxis (Amulet IDE) trial shows.

“The dual-seal Amplatzer Amulet left atrial appendage occluder continued to demonstrate safety and effectiveness through 3 years,” principal investigator Dhanunjaya Lakkireddy, MD, said in a late-breaking session at the recent Transcatheter Cardiovascular Therapeutics annual meeting.

Preliminary results, reported last year, showed that procedural complications were higher with the Amplatzer but that it provided superior closure of the left atrial appendage (LAA) at 45 days and was noninferior with respect to safety at 12 months and efficacy at 18 months.

Amulet IDE is the largest head-to-head comparison of the two devices, enrolling 1,878 high-risk patients with nonvalvular atrial fibrillation undergoing LAA closure to reduce the risk of stroke.

Three-year follow-up was higher with the Amulet device than with the Watchman, at 721 vs. 659 patients, driven by increased deaths (85 vs. 63) and withdrawals (50 vs. 23) in the Watchman group within 18 months, noted Dr. Lakkireddy, Kansas City Heart Rhythm Institute and Research Foundation, Overland Park, Kan.

Use of oral anticoagulation was higher in the Watchman group at 6 months (2.8% vs. 4.7%; P = .04), 18 months (3.1% vs. 5.6%; P = .01), and 3 years (3.7% vs. 7.3%; P < .01).

This was primarily driven by more late device-related thrombus (DRT) after 6 months with the Watchman device than with the Amulet occluder (23 vs. 10). “Perhaps the dual-closure mechanism of the Amulet explains this fundamental difference, where you have a nice smooth disc that covers the ostium,” he posited.

At 3 years, rates of cardiovascular death trended lower with Amulet than with Watchman (6.6% vs. 8.5%; P = .14), as did all-cause deaths (14.6% vs. 17.9%; P = .07).

Most cardiovascular deaths in the Amulet group were not preceded by a device factor, whereas DRT (1 vs. 4) and peridevice leak 3 mm or more (5 vs. 15) frequently preceded these deaths in the Watchman group, Dr. Lakkireddy observed. No pericardial effusion-related deaths occurred in either group.

Major bleeding, however, trended higher for the Amulet, at 16.1%, compared with 14.7% for the Watchman (P = .46). Ischemic stroke and systemic embolic rates also trended higher for Amulet, at 5%, and 4.6% for Watchman.

The protocol recommended aspirin only for both groups after 6 months. None of the 29 Amulet and 3 of the 29 Watchman patients with an ischemic stroke were on oral anticoagulation at the time of the stroke.

Device factors, however, frequently preceded ischemic strokes in the Watchman group, Dr. Lakkireddy said. DRT occurred in 1 patient with Amulet and 2 patients with Watchman and peridevice leak in 3 with Amulet and 15 with Watchman. “Again, the peridevice leak issue really stands out as an important factor,” he said at the meeting, which was sponsored by the Cardiovascular Research Foundation.

Based on “data from the large trials, it’s clearly evident that the presence of peridevice leak significantly raises the risk of stroke in follow-up,” he said. “So, attention has to be paid to the choice of the device and how we can mitigate the risk of peridevice leaks in these patients.”

The composite of stroke, systemic embolism, and cardiovascular death occurred in 11.1% of patients with Amulet and 12.7% with Watchman (P = .31).

A version of this article first appeared on Medscape.com.

The Amplatzer Amulet (Abbott) and first-generation Watchman 2.5 (Boston Scientific) devices provide relatively comparable results out to 3 years after left atrial appendage occlusion (LAAO), longer follow-up from the Amplatzer Amulet Left Atrial Appendage Occluder Versus Watchman Device for Stroke Prophylaxis (Amulet IDE) trial shows.

“The dual-seal Amplatzer Amulet left atrial appendage occluder continued to demonstrate safety and effectiveness through 3 years,” principal investigator Dhanunjaya Lakkireddy, MD, said in a late-breaking session at the recent Transcatheter Cardiovascular Therapeutics annual meeting.

Preliminary results, reported last year, showed that procedural complications were higher with the Amplatzer but that it provided superior closure of the left atrial appendage (LAA) at 45 days and was noninferior with respect to safety at 12 months and efficacy at 18 months.

Amulet IDE is the largest head-to-head comparison of the two devices, enrolling 1,878 high-risk patients with nonvalvular atrial fibrillation undergoing LAA closure to reduce the risk of stroke.

Three-year follow-up was higher with the Amulet device than with the Watchman, at 721 vs. 659 patients, driven by increased deaths (85 vs. 63) and withdrawals (50 vs. 23) in the Watchman group within 18 months, noted Dr. Lakkireddy, Kansas City Heart Rhythm Institute and Research Foundation, Overland Park, Kan.

Use of oral anticoagulation was higher in the Watchman group at 6 months (2.8% vs. 4.7%; P = .04), 18 months (3.1% vs. 5.6%; P = .01), and 3 years (3.7% vs. 7.3%; P < .01).

This was primarily driven by more late device-related thrombus (DRT) after 6 months with the Watchman device than with the Amulet occluder (23 vs. 10). “Perhaps the dual-closure mechanism of the Amulet explains this fundamental difference, where you have a nice smooth disc that covers the ostium,” he posited.

At 3 years, rates of cardiovascular death trended lower with Amulet than with Watchman (6.6% vs. 8.5%; P = .14), as did all-cause deaths (14.6% vs. 17.9%; P = .07).

Most cardiovascular deaths in the Amulet group were not preceded by a device factor, whereas DRT (1 vs. 4) and peridevice leak 3 mm or more (5 vs. 15) frequently preceded these deaths in the Watchman group, Dr. Lakkireddy observed. No pericardial effusion-related deaths occurred in either group.

Major bleeding, however, trended higher for the Amulet, at 16.1%, compared with 14.7% for the Watchman (P = .46). Ischemic stroke and systemic embolic rates also trended higher for Amulet, at 5%, and 4.6% for Watchman.

The protocol recommended aspirin only for both groups after 6 months. None of the 29 Amulet and 3 of the 29 Watchman patients with an ischemic stroke were on oral anticoagulation at the time of the stroke.

Device factors, however, frequently preceded ischemic strokes in the Watchman group, Dr. Lakkireddy said. DRT occurred in 1 patient with Amulet and 2 patients with Watchman and peridevice leak in 3 with Amulet and 15 with Watchman. “Again, the peridevice leak issue really stands out as an important factor,” he said at the meeting, which was sponsored by the Cardiovascular Research Foundation.

Based on “data from the large trials, it’s clearly evident that the presence of peridevice leak significantly raises the risk of stroke in follow-up,” he said. “So, attention has to be paid to the choice of the device and how we can mitigate the risk of peridevice leaks in these patients.”

The composite of stroke, systemic embolism, and cardiovascular death occurred in 11.1% of patients with Amulet and 12.7% with Watchman (P = .31).

A version of this article first appeared on Medscape.com.