Thrombosis

Some, perhaps many, previously unrecognized cases of atrial fibrillation (AF) will come to light in a screening program aimed at older asymptomatic adults. The key question is whether the challenges of such systematic but age-restricted AF screening in the community, with oral anticoagulation (OAC) offered to those found to have the arrhythmia, is worthwhile in preventing events such as death or stroke.
 

Now there is evidence supporting such a clinical benefit from a large, prospective, randomized trial. A screening program restricted to people 75 or 76 years of age in two Swedish communities, which called on them to use a handheld single-lead ECG system at home intermittently for 2 weeks, was followed by a slight drop in clinical events over about 7 years.

The 4% decline in risk (P = .045) in the STROKESTOP trial’s “intention-to-treat” (ITT) analysis yielded a number needed to treat of 91; that is, that many people had to be targeted by the screening program to prevent one primary-endpoint clinical event.

Those included ischemic stroke, systemic thromboembolism, hospitalization for severe bleeding, and death from any cause, investigators reported April 23 during the virtual European Heart Rhythm Association (EHRA) 2021 Congress.

If that benefit and its significance seem marginal, some secondary findings might be reassuring. Half the population of the target age in the two communities – 13,979 randomly selected people – were invited to join the trial and follow the screening protocol, comprising the ITT cohort. The other half, numbering 13,996, was not invited and served as control subjects.

However, only 51% of the ITT cohort accepted the invitation and participated in the trial; they represented the “as-treated” cohort, observed Emma Svennberg, MD, PhD, Karolinska Institute, Danderyd Hospital, Stockholm, who presented the analysis at the EHRA sessions.

The screening protocol identified untreated AF, whether previously known or unknown, in about 5% of the 7,165 as-treated screening participants; OAC was initiated in about three-fourths of those cases.

The as-treated group, on their own, benefited with a 24% drop in the prospectively defined secondary endpoint of ischemic stroke, compared with the entire control group.

The clinical benefit in the ITT population was “small but significant,” but over the same period in the as-treated cohort, there was a highly significant drop in risk for ischemic stroke, Dr. Svennberg said in an interview.

The trial’s lead message, she said, is that “screening for atrial fibrillation in an elderly population reduces the risk of death and ischemic stroke without increasing the risk of bleeding.”
 

Caveats: As-treated vs. ITT

But there are caveats that complicate interpretation of the trial and, Dr. Svennberg proposed, point to the importance of that interpretation of both the ITT and as-treated analyses.

“We detected significantly more atrial fibrillation in the group that was randomized to screening. A major strength of our study was that we referred all of those individuals for a structured follow-up within the study,” she said. “Although the focus of the follow-up was oral anticoagulant therapy, other risk factors were also assessed and managed, such as hypertension and diabetes.”

It’s possible that increased detection of AF followed by such structured management contributed to the observed benefit, Dr. Svennberg proposed.

However, the exclusion of those in the prespecified ITT population who declined to be screened or otherwise didn’t participate left an as-treated cohort that was healthier than the ITT population or the control group.

Indeed, the nonparticipating invitees were sicker, with significantly more diabetes, vascular disease, hypertension, and heart failure, and higher CHA2DS2VASc stroke risk scores than those who agreed to participate.

“We took a more difficult route in setting up this study, in that we identified all individuals aged 75 to 76 residing in our two regions and excluded no one,” Dr. Svennberg said in an interview. “That means even individuals with end-stage disease, severe dementia, bedridden in nursing homes, et cetera, were also randomized but perhaps not likely or eligible to participate.”

Therefore, some invitees were unable to join the study even as others might have declined “out of low interest” or other personal reasons, she said. “We believe that this mimics how a population-based screening program would be performed if done in our country.”

In the ITT analysis, screening successfully identified previously unknown or untreated cases of AF, which led to expanded OAC use and intensified risk-factor management, “which was key to a successful outcome.”

In the as-treated analysis, Dr. Svennberg said, “I think a combination of the intervention and the population being overall more healthy was driving the secondary endpoint.”
 

Systematic vs. opportunistic screening

Although “opportunistic screening in individuals aged 65 and older” is recommended by current European Society of Cardiology guidelines, systematic screening, such as that used in STROKESTOP, has a much weaker evidence base, observed Renate B. Schnabel, MD, PhD, University Heart & Vascular Center, Hamburg, Germany, as the invited discussant after the STROKESTOP presentation.

STROKESTOP “is one of the first studies, if not the first study,” to show a clinical benefit from screening for AF, Dr. Schnabel said.

Fewer-than-projected primary outcome events were seen during the trial, and event curves for screened and control participants didn’t start to separate until about 4 years into the study, she said. It therefore might take a long time for the screened elderly to realize the clinical benefits of screening.

Studies such as the recent SCREEN-AF and mSTOPS have amply shown that AF screening in the asymptomatic elderly can reveal previously unrecognized AF far more often than would be detected in routine practice, allowing them the opportunity to go on OAC. But the trials weren’t able to show whether the benefits of such management outweigh the risks or costs.

Indeed, on April 20, the U.S. Preventive Services Task Force (USPSTF) released a draft recommendation statement concluding that “the current evidence is insufficient to assess the balance of benefits and harms” associated with AF screening in asymptomatic people at least 50 years of age.

In STROKESTOP, however, benefit for the primary outcome reached significance in the prespecified ITT analysis and “appeared to be driven by the reduction in ischemic stroke incidence,” Dr. Schnabel said.

“The future guidelines have gained strong evidence to judge on systematic atrial fibrillation screening” as it was performed in the trial, she said. “How to implement atrial fibrillation screening, including systematic screening in health care systems across Europe and beyond, remains an open question.”
 

A randomized population

STROKESTOP considered all 75- and 76-year-olds living in Sweden’s Stockholm County (n = 23,888) and the Halland region (n = 4,880) and randomly assigned them to the ITT group or a control group, with stratification by sex, birth year, and geographic region. In both groups, 54.6% were female and the mean CHA2DS2VASc score was 3.5.

People assigned to the ITT cohort were invited to be screened and followed. Those who agreed to participate underwent a baseline ECG assessment to detect or rule out permanent AF. Guideline-based OAC and follow-up was offered to those found with the arrhythmia. Those in sinus rhythm with no history of AF used a handheld single-lead ECG recorder (Zenicor) for 30 seconds twice daily for 14 days.

Structured management, including OAC, was offered to anyone demonstrating sufficient AF, that is, at least one bout without p waves in one 30-second recording or at least two such episodes lasting 10-29 seconds during the 2-week screening period.

In the ITT analysis, the hazard ratio (HR) for the composite clinical primary endpoint was 0.96 (95% confidence interval, 0.920-0.999; P = .045), but in the as-treated analysis, the HR for ischemic stroke was 0.76 (95% CI, 0.68-0.87; P < .001).

“I believe that this will likely be generalizable to most countries’ elderly residents,” Dr. Svennberg said. “I think if we can find a significant difference in our elderly population in Sweden, most countries will be able to do so, or find even more significant results.”

That’s because “baseline detection of AF in Sweden is high,” she said, “so new detection is likely more difficult.” Also, in Sweden, “care can be sought without monetary concern, and prescriptions are provided at low costs to the patients.” Therefore, patients newly identified with AF, whether in studies or not, “would likely be started on therapy.”

It will be important to know whether the screening strategy is cost-effective, Dr. Schnabel said, because “the overall effect, with a hazard ratio of 0.96, is not too big, and costs incurred by systematic screening are comparatively high.”

STROKESTOP “now provides sound information for cost-effectiveness analyses, which to date have largely relied on assumptions.”

STROKESTOP was partially supported by Carl Bennet AB, Boehringer-Ingelheim, Bayer, Bristol-Meyers Squibb, and Pfizer. Dr. Svennberg disclosed receiving fees for lectures or consulting from Bayer, Bristol-Meyers Squibb, Pfizer, Boehringer-Ingelheim, Merck Sharp & Dohme, and Sanofi; and institutional grants from Roche Diagnostics and Carl Bennett Ltd.

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

Some, perhaps many, previously unrecognized cases of atrial fibrillation (AF) will come to light in a screening program aimed at older asymptomatic adults. The key question is whether the challenges of such systematic but age-restricted AF screening in the community, with oral anticoagulation (OAC) offered to those found to have the arrhythmia, is worthwhile in preventing events such as death or stroke.
 

Now there is evidence supporting such a clinical benefit from a large, prospective, randomized trial. A screening program restricted to people 75 or 76 years of age in two Swedish communities, which called on them to use a handheld single-lead ECG system at home intermittently for 2 weeks, was followed by a slight drop in clinical events over about 7 years.

The 4% decline in risk (P = .045) in the STROKESTOP trial’s “intention-to-treat” (ITT) analysis yielded a number needed to treat of 91; that is, that many people had to be targeted by the screening program to prevent one primary-endpoint clinical event.

Those included ischemic stroke, systemic thromboembolism, hospitalization for severe bleeding, and death from any cause, investigators reported April 23 during the virtual European Heart Rhythm Association (EHRA) 2021 Congress.

If that benefit and its significance seem marginal, some secondary findings might be reassuring. Half the population of the target age in the two communities – 13,979 randomly selected people – were invited to join the trial and follow the screening protocol, comprising the ITT cohort. The other half, numbering 13,996, was not invited and served as control subjects.

However, only 51% of the ITT cohort accepted the invitation and participated in the trial; they represented the “as-treated” cohort, observed Emma Svennberg, MD, PhD, Karolinska Institute, Danderyd Hospital, Stockholm, who presented the analysis at the EHRA sessions.

The screening protocol identified untreated AF, whether previously known or unknown, in about 5% of the 7,165 as-treated screening participants; OAC was initiated in about three-fourths of those cases.

The as-treated group, on their own, benefited with a 24% drop in the prospectively defined secondary endpoint of ischemic stroke, compared with the entire control group.

The clinical benefit in the ITT population was “small but significant,” but over the same period in the as-treated cohort, there was a highly significant drop in risk for ischemic stroke, Dr. Svennberg said in an interview.

The trial’s lead message, she said, is that “screening for atrial fibrillation in an elderly population reduces the risk of death and ischemic stroke without increasing the risk of bleeding.”
 

Caveats: As-treated vs. ITT

But there are caveats that complicate interpretation of the trial and, Dr. Svennberg proposed, point to the importance of that interpretation of both the ITT and as-treated analyses.

“We detected significantly more atrial fibrillation in the group that was randomized to screening. A major strength of our study was that we referred all of those individuals for a structured follow-up within the study,” she said. “Although the focus of the follow-up was oral anticoagulant therapy, other risk factors were also assessed and managed, such as hypertension and diabetes.”

It’s possible that increased detection of AF followed by such structured management contributed to the observed benefit, Dr. Svennberg proposed.

However, the exclusion of those in the prespecified ITT population who declined to be screened or otherwise didn’t participate left an as-treated cohort that was healthier than the ITT population or the control group.

Indeed, the nonparticipating invitees were sicker, with significantly more diabetes, vascular disease, hypertension, and heart failure, and higher CHA2DS2VASc stroke risk scores than those who agreed to participate.

“We took a more difficult route in setting up this study, in that we identified all individuals aged 75 to 76 residing in our two regions and excluded no one,” Dr. Svennberg said in an interview. “That means even individuals with end-stage disease, severe dementia, bedridden in nursing homes, et cetera, were also randomized but perhaps not likely or eligible to participate.”

Therefore, some invitees were unable to join the study even as others might have declined “out of low interest” or other personal reasons, she said. “We believe that this mimics how a population-based screening program would be performed if done in our country.”

In the ITT analysis, screening successfully identified previously unknown or untreated cases of AF, which led to expanded OAC use and intensified risk-factor management, “which was key to a successful outcome.”

In the as-treated analysis, Dr. Svennberg said, “I think a combination of the intervention and the population being overall more healthy was driving the secondary endpoint.”
 

Systematic vs. opportunistic screening

Although “opportunistic screening in individuals aged 65 and older” is recommended by current European Society of Cardiology guidelines, systematic screening, such as that used in STROKESTOP, has a much weaker evidence base, observed Renate B. Schnabel, MD, PhD, University Heart & Vascular Center, Hamburg, Germany, as the invited discussant after the STROKESTOP presentation.

STROKESTOP “is one of the first studies, if not the first study,” to show a clinical benefit from screening for AF, Dr. Schnabel said.

Fewer-than-projected primary outcome events were seen during the trial, and event curves for screened and control participants didn’t start to separate until about 4 years into the study, she said. It therefore might take a long time for the screened elderly to realize the clinical benefits of screening.

Studies such as the recent SCREEN-AF and mSTOPS have amply shown that AF screening in the asymptomatic elderly can reveal previously unrecognized AF far more often than would be detected in routine practice, allowing them the opportunity to go on OAC. But the trials weren’t able to show whether the benefits of such management outweigh the risks or costs.

Indeed, on April 20, the U.S. Preventive Services Task Force (USPSTF) released a draft recommendation statement concluding that “the current evidence is insufficient to assess the balance of benefits and harms” associated with AF screening in asymptomatic people at least 50 years of age.

In STROKESTOP, however, benefit for the primary outcome reached significance in the prespecified ITT analysis and “appeared to be driven by the reduction in ischemic stroke incidence,” Dr. Schnabel said.

“The future guidelines have gained strong evidence to judge on systematic atrial fibrillation screening” as it was performed in the trial, she said. “How to implement atrial fibrillation screening, including systematic screening in health care systems across Europe and beyond, remains an open question.”
 

A randomized population

STROKESTOP considered all 75- and 76-year-olds living in Sweden’s Stockholm County (n = 23,888) and the Halland region (n = 4,880) and randomly assigned them to the ITT group or a control group, with stratification by sex, birth year, and geographic region. In both groups, 54.6% were female and the mean CHA2DS2VASc score was 3.5.

People assigned to the ITT cohort were invited to be screened and followed. Those who agreed to participate underwent a baseline ECG assessment to detect or rule out permanent AF. Guideline-based OAC and follow-up was offered to those found with the arrhythmia. Those in sinus rhythm with no history of AF used a handheld single-lead ECG recorder (Zenicor) for 30 seconds twice daily for 14 days.

Structured management, including OAC, was offered to anyone demonstrating sufficient AF, that is, at least one bout without p waves in one 30-second recording or at least two such episodes lasting 10-29 seconds during the 2-week screening period.

In the ITT analysis, the hazard ratio (HR) for the composite clinical primary endpoint was 0.96 (95% confidence interval, 0.920-0.999; P = .045), but in the as-treated analysis, the HR for ischemic stroke was 0.76 (95% CI, 0.68-0.87; P < .001).

“I believe that this will likely be generalizable to most countries’ elderly residents,” Dr. Svennberg said. “I think if we can find a significant difference in our elderly population in Sweden, most countries will be able to do so, or find even more significant results.”

That’s because “baseline detection of AF in Sweden is high,” she said, “so new detection is likely more difficult.” Also, in Sweden, “care can be sought without monetary concern, and prescriptions are provided at low costs to the patients.” Therefore, patients newly identified with AF, whether in studies or not, “would likely be started on therapy.”

It will be important to know whether the screening strategy is cost-effective, Dr. Schnabel said, because “the overall effect, with a hazard ratio of 0.96, is not too big, and costs incurred by systematic screening are comparatively high.”

STROKESTOP “now provides sound information for cost-effectiveness analyses, which to date have largely relied on assumptions.”

STROKESTOP was partially supported by Carl Bennet AB, Boehringer-Ingelheim, Bayer, Bristol-Meyers Squibb, and Pfizer. Dr. Svennberg disclosed receiving fees for lectures or consulting from Bayer, Bristol-Meyers Squibb, Pfizer, Boehringer-Ingelheim, Merck Sharp & Dohme, and Sanofi; and institutional grants from Roche Diagnostics and Carl Bennett Ltd.

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

Some, perhaps many, previously unrecognized cases of atrial fibrillation (AF) will come to light in a screening program aimed at older asymptomatic adults. The key question is whether the challenges of such systematic but age-restricted AF screening in the community, with oral anticoagulation (OAC) offered to those found to have the arrhythmia, is worthwhile in preventing events such as death or stroke.
 

Now there is evidence supporting such a clinical benefit from a large, prospective, randomized trial. A screening program restricted to people 75 or 76 years of age in two Swedish communities, which called on them to use a handheld single-lead ECG system at home intermittently for 2 weeks, was followed by a slight drop in clinical events over about 7 years.

The 4% decline in risk (P = .045) in the STROKESTOP trial’s “intention-to-treat” (ITT) analysis yielded a number needed to treat of 91; that is, that many people had to be targeted by the screening program to prevent one primary-endpoint clinical event.

Those included ischemic stroke, systemic thromboembolism, hospitalization for severe bleeding, and death from any cause, investigators reported April 23 during the virtual European Heart Rhythm Association (EHRA) 2021 Congress.

If that benefit and its significance seem marginal, some secondary findings might be reassuring. Half the population of the target age in the two communities – 13,979 randomly selected people – were invited to join the trial and follow the screening protocol, comprising the ITT cohort. The other half, numbering 13,996, was not invited and served as control subjects.

However, only 51% of the ITT cohort accepted the invitation and participated in the trial; they represented the “as-treated” cohort, observed Emma Svennberg, MD, PhD, Karolinska Institute, Danderyd Hospital, Stockholm, who presented the analysis at the EHRA sessions.

The screening protocol identified untreated AF, whether previously known or unknown, in about 5% of the 7,165 as-treated screening participants; OAC was initiated in about three-fourths of those cases.

The as-treated group, on their own, benefited with a 24% drop in the prospectively defined secondary endpoint of ischemic stroke, compared with the entire control group.

The clinical benefit in the ITT population was “small but significant,” but over the same period in the as-treated cohort, there was a highly significant drop in risk for ischemic stroke, Dr. Svennberg said in an interview.

The trial’s lead message, she said, is that “screening for atrial fibrillation in an elderly population reduces the risk of death and ischemic stroke without increasing the risk of bleeding.”
 

Caveats: As-treated vs. ITT

But there are caveats that complicate interpretation of the trial and, Dr. Svennberg proposed, point to the importance of that interpretation of both the ITT and as-treated analyses.

“We detected significantly more atrial fibrillation in the group that was randomized to screening. A major strength of our study was that we referred all of those individuals for a structured follow-up within the study,” she said. “Although the focus of the follow-up was oral anticoagulant therapy, other risk factors were also assessed and managed, such as hypertension and diabetes.”

It’s possible that increased detection of AF followed by such structured management contributed to the observed benefit, Dr. Svennberg proposed.

However, the exclusion of those in the prespecified ITT population who declined to be screened or otherwise didn’t participate left an as-treated cohort that was healthier than the ITT population or the control group.

Indeed, the nonparticipating invitees were sicker, with significantly more diabetes, vascular disease, hypertension, and heart failure, and higher CHA2DS2VASc stroke risk scores than those who agreed to participate.

“We took a more difficult route in setting up this study, in that we identified all individuals aged 75 to 76 residing in our two regions and excluded no one,” Dr. Svennberg said in an interview. “That means even individuals with end-stage disease, severe dementia, bedridden in nursing homes, et cetera, were also randomized but perhaps not likely or eligible to participate.”

Therefore, some invitees were unable to join the study even as others might have declined “out of low interest” or other personal reasons, she said. “We believe that this mimics how a population-based screening program would be performed if done in our country.”

In the ITT analysis, screening successfully identified previously unknown or untreated cases of AF, which led to expanded OAC use and intensified risk-factor management, “which was key to a successful outcome.”

In the as-treated analysis, Dr. Svennberg said, “I think a combination of the intervention and the population being overall more healthy was driving the secondary endpoint.”
 

Systematic vs. opportunistic screening

Although “opportunistic screening in individuals aged 65 and older” is recommended by current European Society of Cardiology guidelines, systematic screening, such as that used in STROKESTOP, has a much weaker evidence base, observed Renate B. Schnabel, MD, PhD, University Heart & Vascular Center, Hamburg, Germany, as the invited discussant after the STROKESTOP presentation.

STROKESTOP “is one of the first studies, if not the first study,” to show a clinical benefit from screening for AF, Dr. Schnabel said.

Fewer-than-projected primary outcome events were seen during the trial, and event curves for screened and control participants didn’t start to separate until about 4 years into the study, she said. It therefore might take a long time for the screened elderly to realize the clinical benefits of screening.

Studies such as the recent SCREEN-AF and mSTOPS have amply shown that AF screening in the asymptomatic elderly can reveal previously unrecognized AF far more often than would be detected in routine practice, allowing them the opportunity to go on OAC. But the trials weren’t able to show whether the benefits of such management outweigh the risks or costs.

Indeed, on April 20, the U.S. Preventive Services Task Force (USPSTF) released a draft recommendation statement concluding that “the current evidence is insufficient to assess the balance of benefits and harms” associated with AF screening in asymptomatic people at least 50 years of age.

In STROKESTOP, however, benefit for the primary outcome reached significance in the prespecified ITT analysis and “appeared to be driven by the reduction in ischemic stroke incidence,” Dr. Schnabel said.

“The future guidelines have gained strong evidence to judge on systematic atrial fibrillation screening” as it was performed in the trial, she said. “How to implement atrial fibrillation screening, including systematic screening in health care systems across Europe and beyond, remains an open question.”
 

A randomized population

STROKESTOP considered all 75- and 76-year-olds living in Sweden’s Stockholm County (n = 23,888) and the Halland region (n = 4,880) and randomly assigned them to the ITT group or a control group, with stratification by sex, birth year, and geographic region. In both groups, 54.6% were female and the mean CHA2DS2VASc score was 3.5.

People assigned to the ITT cohort were invited to be screened and followed. Those who agreed to participate underwent a baseline ECG assessment to detect or rule out permanent AF. Guideline-based OAC and follow-up was offered to those found with the arrhythmia. Those in sinus rhythm with no history of AF used a handheld single-lead ECG recorder (Zenicor) for 30 seconds twice daily for 14 days.

Structured management, including OAC, was offered to anyone demonstrating sufficient AF, that is, at least one bout without p waves in one 30-second recording or at least two such episodes lasting 10-29 seconds during the 2-week screening period.

In the ITT analysis, the hazard ratio (HR) for the composite clinical primary endpoint was 0.96 (95% confidence interval, 0.920-0.999; P = .045), but in the as-treated analysis, the HR for ischemic stroke was 0.76 (95% CI, 0.68-0.87; P < .001).

“I believe that this will likely be generalizable to most countries’ elderly residents,” Dr. Svennberg said. “I think if we can find a significant difference in our elderly population in Sweden, most countries will be able to do so, or find even more significant results.”

That’s because “baseline detection of AF in Sweden is high,” she said, “so new detection is likely more difficult.” Also, in Sweden, “care can be sought without monetary concern, and prescriptions are provided at low costs to the patients.” Therefore, patients newly identified with AF, whether in studies or not, “would likely be started on therapy.”

It will be important to know whether the screening strategy is cost-effective, Dr. Schnabel said, because “the overall effect, with a hazard ratio of 0.96, is not too big, and costs incurred by systematic screening are comparatively high.”

STROKESTOP “now provides sound information for cost-effectiveness analyses, which to date have largely relied on assumptions.”

STROKESTOP was partially supported by Carl Bennet AB, Boehringer-Ingelheim, Bayer, Bristol-Meyers Squibb, and Pfizer. Dr. Svennberg disclosed receiving fees for lectures or consulting from Bayer, Bristol-Meyers Squibb, Pfizer, Boehringer-Ingelheim, Merck Sharp & Dohme, and Sanofi; and institutional grants from Roche Diagnostics and Carl Bennett Ltd.

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

Excess mortality among people with endogenous Cushing’s syndrome (CS) has declined in the past 20 years yet remains three times higher than in the general population, new research finds.

Among more than 90,000 individuals with endogenous CS, the overall proportion of mortality – defined as the ratio of the number of deaths from CS divided by the total number of CS patients – was 0.05, and the standardized mortality rate was an “unacceptable” three times that of the general population, Padiporn Limumpornpetch, MD, reported on March 20 at ENDO 2021: The Endocrine Society Annual Meeting.

Excess deaths were higher among those with adrenal CS, compared with those with Cushing’s disease. The most common causes of death among those with CS were cardiovascular diseases, cerebrovascular accident, infection, and malignancy, noted Dr. Limumpornpetch, of Songkla University, Hat Yai, Thailand, who is also a PhD student at the University of Leeds, United Kingdom.

“While mortality has improved since 2000, it is still significantly compromised compared to the background population ... The causes of death highlight the need for aggressive management of cardiovascular risk, prevention of thromboembolism, infection control, and a normalized cortisol level,” she said.

Asked to comment, Maria Fleseriu, MD, told this news organization that the new data show “we are making improvements in the care of patients with CS and thus outcomes, but we are not there yet ... This meta-analysis highlights the whole spectrum of acute and life-threatening complications in CS and their high prevalence, even before disease diagnosis and after successful surgery.”

She noted that although she wasn’t surprised by the overall results, “the improvement over time was indeed lower than I expected. However, interestingly here, the risk of mortality in adrenal Cushing’s was unexpectedly high despite patients with adrenal cancer being excluded.”

Dr. Fleseriu, who is director of the Pituitary Center at Oregon Health and Science University, Portland, advised, “Management of hyperglycemia and diabetes, hypertension, hypokalemia, hyperlipidemia, and other cardiovascular risk factors is generally undertaken in accordance with standard of clinical care.”

“But we should focus more on optimizing more aggressively this care in addition to the specific Cushing’s treatment,” she stressed.

In addition, she noted, “Medical therapy for CS may be needed even prior to surgery in severe and/or prolonged hypercortisolism to decrease complications ... We definitely need a multidisciplinary approach to address complications and etiologic treatment as well as the reduced long-term quality of life in patients with CS.”

Largest study in scale and scope of Cushing’s syndrome mortality

Endogenous Cushing’s syndrome occurs when the body overproduces cortisol. The most common cause of the latter is a tumor of the pituitary gland (Cushing’s disease), but another cause is a usually benign tumor of the adrenal glands (adrenal Cushing’s syndrome). Surgery is the mainstay of initial treatment of Cushing’s syndrome. If an operation to remove the tumor fails to cause remission, medications are available.

Prior to this new meta-analysis, there had been limited data on mortality among patients with endogenous CS. Research has mostly been limited to single-cohort studies. A previous systematic review/meta-analysis comprised only seven articles with 780 patients. All the studies were conducted prior to 2012, and most were limited to Cushing’s disease.

“In 2021, we lacked a detailed understanding of patient outcomes and mortality because of the rarity of Cushing’s syndrome,” Dr. Limumpornpetch noted.

The current meta-analysis included 91 articles that reported mortality among patients with endogenous CS. There was a total of 19,181 patients from 92 study cohorts, including 49 studies on CD (n = 14,971), 24 studies on adrenal CS (n = 2304), and 19 studies that included both (n = 1906).

Among 21 studies that reported standardized mortality rate (SMR) data, including 13 CD studies (n = 2160) and seven on adrenal CS (n = 1531), the overall increase in mortality compared to the background population was a significant 3.00 (range, 1.15-7.84).

This SMR was higher among patients with adrenal Cushing’s syndrome (3.3) versus Cushing’s disease (2.8) (P = .003) and among patients who had active disease (5.7) versus those whose disease was in remission (2.3) (P < .001).

The SMR was also worse among patients with Cushing’s disease with larger tumors (macroadenomas), at 7.4, than among patients with very small tumors (microadenomas), at 1.9 (P = .004).

The proportion of death was 0.05 for CS overall, with 0.04 for CD and 0.02 for adrenal adenomas.

Compared to studies published prior to the year 2000, more recent studies seem to reflect advances in treatment and care. The overall proportion of death for all CS cohorts dropped from 0.10 to 0.03 (P < .001); for all CD cohorts, it dropped from 0.14 to 0.03; and for adrenal CS cohorts, it dropped from 0.09 to 0.03 (P = .04).

Causes of death were cardiovascular diseases (29.5% of cases), cerebrovascular accident (11.5%), infection (10.5%), and malignancy (10.1%). Less common causes of death were gastrointestinal bleeding and acute pancreatitis (3.7%), active CS (3.5%), adrenal insufficiency (2.5%), suicide (2.5%), and surgery (1.6%).

Overall, in the CS groups, the proportion of deaths within 30 days of surgery dropped from 0.04 prior to 2000 to 0.01 since (P = .07). For CD, the proportion dropped from 0.02 to 0.01 (P = .25).

Preventing perioperative mortality: Consider thromboprophylaxis

Dr. Fleseriu told this news organization that she believes hypercoagulability is “the least recognized complication with a big role in mortality.” Because most of the perioperative mortality is due to venous thromboembolism and infections, “thromboprophylaxis should be considered for CS patients with severe hypercortisolism and/or postoperatively, based on individual risk factors of thromboembolism and bleeding.”

Recently, Dr. Fleseriu’s group showed in a single retrospective study that the risk for arterial and venous thromboembolic events among patients with CS was approximately 20%. Many patients experienced more than one event. Risk was higher 30 to 60 days postoperatively.

The odds ratio of venous thromoboembolism among patients with CS was 18 times higher than in the normal population.

“Due to the additional thrombotic risk of surgery or any invasive procedure, anticoagulation prophylaxis should be at least considered in all patients with Cushing’s syndrome and balanced with individual bleeding risk,” Dr. Fleseriu advised.

A recent Pituitary Society workshop discussed the management of complications of CS at length; proceedings will be published soon, she noted.

Dr. Limumpornpetch commented, “We look forward to the day when our interdisciplinary approach to managing these challenging patients can deliver outcomes similar to the background population.”

Dr. Limumpornpetch has disclosed no relevant financial relationships. Dr. Fleseriu has been a scientific consultant to Recordati, Sparrow, and Strongbridge and has received grants (inst) from Novartis and Strongbridge.

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

Excess mortality among people with endogenous Cushing’s syndrome (CS) has declined in the past 20 years yet remains three times higher than in the general population, new research finds.

Among more than 90,000 individuals with endogenous CS, the overall proportion of mortality – defined as the ratio of the number of deaths from CS divided by the total number of CS patients – was 0.05, and the standardized mortality rate was an “unacceptable” three times that of the general population, Padiporn Limumpornpetch, MD, reported on March 20 at ENDO 2021: The Endocrine Society Annual Meeting.

Excess deaths were higher among those with adrenal CS, compared with those with Cushing’s disease. The most common causes of death among those with CS were cardiovascular diseases, cerebrovascular accident, infection, and malignancy, noted Dr. Limumpornpetch, of Songkla University, Hat Yai, Thailand, who is also a PhD student at the University of Leeds, United Kingdom.

“While mortality has improved since 2000, it is still significantly compromised compared to the background population ... The causes of death highlight the need for aggressive management of cardiovascular risk, prevention of thromboembolism, infection control, and a normalized cortisol level,” she said.

Asked to comment, Maria Fleseriu, MD, told this news organization that the new data show “we are making improvements in the care of patients with CS and thus outcomes, but we are not there yet ... This meta-analysis highlights the whole spectrum of acute and life-threatening complications in CS and their high prevalence, even before disease diagnosis and after successful surgery.”

She noted that although she wasn’t surprised by the overall results, “the improvement over time was indeed lower than I expected. However, interestingly here, the risk of mortality in adrenal Cushing’s was unexpectedly high despite patients with adrenal cancer being excluded.”

Dr. Fleseriu, who is director of the Pituitary Center at Oregon Health and Science University, Portland, advised, “Management of hyperglycemia and diabetes, hypertension, hypokalemia, hyperlipidemia, and other cardiovascular risk factors is generally undertaken in accordance with standard of clinical care.”

“But we should focus more on optimizing more aggressively this care in addition to the specific Cushing’s treatment,” she stressed.

In addition, she noted, “Medical therapy for CS may be needed even prior to surgery in severe and/or prolonged hypercortisolism to decrease complications ... We definitely need a multidisciplinary approach to address complications and etiologic treatment as well as the reduced long-term quality of life in patients with CS.”

Largest study in scale and scope of Cushing’s syndrome mortality

Endogenous Cushing’s syndrome occurs when the body overproduces cortisol. The most common cause of the latter is a tumor of the pituitary gland (Cushing’s disease), but another cause is a usually benign tumor of the adrenal glands (adrenal Cushing’s syndrome). Surgery is the mainstay of initial treatment of Cushing’s syndrome. If an operation to remove the tumor fails to cause remission, medications are available.

Prior to this new meta-analysis, there had been limited data on mortality among patients with endogenous CS. Research has mostly been limited to single-cohort studies. A previous systematic review/meta-analysis comprised only seven articles with 780 patients. All the studies were conducted prior to 2012, and most were limited to Cushing’s disease.

“In 2021, we lacked a detailed understanding of patient outcomes and mortality because of the rarity of Cushing’s syndrome,” Dr. Limumpornpetch noted.

The current meta-analysis included 91 articles that reported mortality among patients with endogenous CS. There was a total of 19,181 patients from 92 study cohorts, including 49 studies on CD (n = 14,971), 24 studies on adrenal CS (n = 2304), and 19 studies that included both (n = 1906).

Among 21 studies that reported standardized mortality rate (SMR) data, including 13 CD studies (n = 2160) and seven on adrenal CS (n = 1531), the overall increase in mortality compared to the background population was a significant 3.00 (range, 1.15-7.84).

This SMR was higher among patients with adrenal Cushing’s syndrome (3.3) versus Cushing’s disease (2.8) (P = .003) and among patients who had active disease (5.7) versus those whose disease was in remission (2.3) (P < .001).

The SMR was also worse among patients with Cushing’s disease with larger tumors (macroadenomas), at 7.4, than among patients with very small tumors (microadenomas), at 1.9 (P = .004).

The proportion of death was 0.05 for CS overall, with 0.04 for CD and 0.02 for adrenal adenomas.

Compared to studies published prior to the year 2000, more recent studies seem to reflect advances in treatment and care. The overall proportion of death for all CS cohorts dropped from 0.10 to 0.03 (P < .001); for all CD cohorts, it dropped from 0.14 to 0.03; and for adrenal CS cohorts, it dropped from 0.09 to 0.03 (P = .04).

Causes of death were cardiovascular diseases (29.5% of cases), cerebrovascular accident (11.5%), infection (10.5%), and malignancy (10.1%). Less common causes of death were gastrointestinal bleeding and acute pancreatitis (3.7%), active CS (3.5%), adrenal insufficiency (2.5%), suicide (2.5%), and surgery (1.6%).

Overall, in the CS groups, the proportion of deaths within 30 days of surgery dropped from 0.04 prior to 2000 to 0.01 since (P = .07). For CD, the proportion dropped from 0.02 to 0.01 (P = .25).

Preventing perioperative mortality: Consider thromboprophylaxis

Dr. Fleseriu told this news organization that she believes hypercoagulability is “the least recognized complication with a big role in mortality.” Because most of the perioperative mortality is due to venous thromboembolism and infections, “thromboprophylaxis should be considered for CS patients with severe hypercortisolism and/or postoperatively, based on individual risk factors of thromboembolism and bleeding.”

Recently, Dr. Fleseriu’s group showed in a single retrospective study that the risk for arterial and venous thromboembolic events among patients with CS was approximately 20%. Many patients experienced more than one event. Risk was higher 30 to 60 days postoperatively.

The odds ratio of venous thromoboembolism among patients with CS was 18 times higher than in the normal population.

“Due to the additional thrombotic risk of surgery or any invasive procedure, anticoagulation prophylaxis should be at least considered in all patients with Cushing’s syndrome and balanced with individual bleeding risk,” Dr. Fleseriu advised.

A recent Pituitary Society workshop discussed the management of complications of CS at length; proceedings will be published soon, she noted.

Dr. Limumpornpetch commented, “We look forward to the day when our interdisciplinary approach to managing these challenging patients can deliver outcomes similar to the background population.”

Dr. Limumpornpetch has disclosed no relevant financial relationships. Dr. Fleseriu has been a scientific consultant to Recordati, Sparrow, and Strongbridge and has received grants (inst) from Novartis and Strongbridge.

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

Excess mortality among people with endogenous Cushing’s syndrome (CS) has declined in the past 20 years yet remains three times higher than in the general population, new research finds.

Among more than 90,000 individuals with endogenous CS, the overall proportion of mortality – defined as the ratio of the number of deaths from CS divided by the total number of CS patients – was 0.05, and the standardized mortality rate was an “unacceptable” three times that of the general population, Padiporn Limumpornpetch, MD, reported on March 20 at ENDO 2021: The Endocrine Society Annual Meeting.

Excess deaths were higher among those with adrenal CS, compared with those with Cushing’s disease. The most common causes of death among those with CS were cardiovascular diseases, cerebrovascular accident, infection, and malignancy, noted Dr. Limumpornpetch, of Songkla University, Hat Yai, Thailand, who is also a PhD student at the University of Leeds, United Kingdom.

“While mortality has improved since 2000, it is still significantly compromised compared to the background population ... The causes of death highlight the need for aggressive management of cardiovascular risk, prevention of thromboembolism, infection control, and a normalized cortisol level,” she said.

Asked to comment, Maria Fleseriu, MD, told this news organization that the new data show “we are making improvements in the care of patients with CS and thus outcomes, but we are not there yet ... This meta-analysis highlights the whole spectrum of acute and life-threatening complications in CS and their high prevalence, even before disease diagnosis and after successful surgery.”

She noted that although she wasn’t surprised by the overall results, “the improvement over time was indeed lower than I expected. However, interestingly here, the risk of mortality in adrenal Cushing’s was unexpectedly high despite patients with adrenal cancer being excluded.”

Dr. Fleseriu, who is director of the Pituitary Center at Oregon Health and Science University, Portland, advised, “Management of hyperglycemia and diabetes, hypertension, hypokalemia, hyperlipidemia, and other cardiovascular risk factors is generally undertaken in accordance with standard of clinical care.”

“But we should focus more on optimizing more aggressively this care in addition to the specific Cushing’s treatment,” she stressed.

In addition, she noted, “Medical therapy for CS may be needed even prior to surgery in severe and/or prolonged hypercortisolism to decrease complications ... We definitely need a multidisciplinary approach to address complications and etiologic treatment as well as the reduced long-term quality of life in patients with CS.”

Largest study in scale and scope of Cushing’s syndrome mortality

Endogenous Cushing’s syndrome occurs when the body overproduces cortisol. The most common cause of the latter is a tumor of the pituitary gland (Cushing’s disease), but another cause is a usually benign tumor of the adrenal glands (adrenal Cushing’s syndrome). Surgery is the mainstay of initial treatment of Cushing’s syndrome. If an operation to remove the tumor fails to cause remission, medications are available.

Prior to this new meta-analysis, there had been limited data on mortality among patients with endogenous CS. Research has mostly been limited to single-cohort studies. A previous systematic review/meta-analysis comprised only seven articles with 780 patients. All the studies were conducted prior to 2012, and most were limited to Cushing’s disease.

“In 2021, we lacked a detailed understanding of patient outcomes and mortality because of the rarity of Cushing’s syndrome,” Dr. Limumpornpetch noted.

The current meta-analysis included 91 articles that reported mortality among patients with endogenous CS. There was a total of 19,181 patients from 92 study cohorts, including 49 studies on CD (n = 14,971), 24 studies on adrenal CS (n = 2304), and 19 studies that included both (n = 1906).

Among 21 studies that reported standardized mortality rate (SMR) data, including 13 CD studies (n = 2160) and seven on adrenal CS (n = 1531), the overall increase in mortality compared to the background population was a significant 3.00 (range, 1.15-7.84).

This SMR was higher among patients with adrenal Cushing’s syndrome (3.3) versus Cushing’s disease (2.8) (P = .003) and among patients who had active disease (5.7) versus those whose disease was in remission (2.3) (P < .001).

The SMR was also worse among patients with Cushing’s disease with larger tumors (macroadenomas), at 7.4, than among patients with very small tumors (microadenomas), at 1.9 (P = .004).

The proportion of death was 0.05 for CS overall, with 0.04 for CD and 0.02 for adrenal adenomas.

Compared to studies published prior to the year 2000, more recent studies seem to reflect advances in treatment and care. The overall proportion of death for all CS cohorts dropped from 0.10 to 0.03 (P < .001); for all CD cohorts, it dropped from 0.14 to 0.03; and for adrenal CS cohorts, it dropped from 0.09 to 0.03 (P = .04).

Causes of death were cardiovascular diseases (29.5% of cases), cerebrovascular accident (11.5%), infection (10.5%), and malignancy (10.1%). Less common causes of death were gastrointestinal bleeding and acute pancreatitis (3.7%), active CS (3.5%), adrenal insufficiency (2.5%), suicide (2.5%), and surgery (1.6%).

Overall, in the CS groups, the proportion of deaths within 30 days of surgery dropped from 0.04 prior to 2000 to 0.01 since (P = .07). For CD, the proportion dropped from 0.02 to 0.01 (P = .25).

Preventing perioperative mortality: Consider thromboprophylaxis

Dr. Fleseriu told this news organization that she believes hypercoagulability is “the least recognized complication with a big role in mortality.” Because most of the perioperative mortality is due to venous thromboembolism and infections, “thromboprophylaxis should be considered for CS patients with severe hypercortisolism and/or postoperatively, based on individual risk factors of thromboembolism and bleeding.”

Recently, Dr. Fleseriu’s group showed in a single retrospective study that the risk for arterial and venous thromboembolic events among patients with CS was approximately 20%. Many patients experienced more than one event. Risk was higher 30 to 60 days postoperatively.

The odds ratio of venous thromoboembolism among patients with CS was 18 times higher than in the normal population.

“Due to the additional thrombotic risk of surgery or any invasive procedure, anticoagulation prophylaxis should be at least considered in all patients with Cushing’s syndrome and balanced with individual bleeding risk,” Dr. Fleseriu advised.

A recent Pituitary Society workshop discussed the management of complications of CS at length; proceedings will be published soon, she noted.

Dr. Limumpornpetch commented, “We look forward to the day when our interdisciplinary approach to managing these challenging patients can deliver outcomes similar to the background population.”

Dr. Limumpornpetch has disclosed no relevant financial relationships. Dr. Fleseriu has been a scientific consultant to Recordati, Sparrow, and Strongbridge and has received grants (inst) from Novartis and Strongbridge.

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

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

This article was updated 4/13/21.

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

This article was updated 4/13/21.

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

This article was updated 4/13/21.

A new antiplatelet drug with a completely novel mechanism of action may hold the promise of delivering the holy grail – reducing cardiac events without increasing bleeding. That is the hope behind the new class of drugs directed against the platelet collagen glycoprotein VI (GPVI) receptor.

A phase 2 trial with the first agent in this class, known as revacept (advanceCOR), showed no increase in bleeding with the product when added to standard dual-antiplatelet therapy for patients with stable ischemic heart disease undergoing elective percutaneous coronary intervention (PCI), despite the drug’s being used at a dose that has been shown to increase platelet inhibition.

Unfortunately, there was no reduction in the primary clinical efficacy endpoint, a myocardial injury surrogate, but the authors pointed out that the overall event rate was low, and they were hopeful that future trials in a higher-risk population will show efficacy.

The ISAR PLASTER study was published online on March 31 in JAMA Cardiology.

“This new drug is targeting the collagen in the extracellular matrix of atherosclerotic plaque rather than the platelets themselves. So, in theory, this agent should not cause an increase in bleeding,” study author Steffen Massberg, DrMed, said in an interview.

Dr. Massberg explained that revacept targets the binding site for platelets on collagen that is exposed on rupture of atherosclerotic plaques and is a major trigger of platelet activation.

“In contrast to aspirin and P2Y12 inhibitors, which target all platelets, revacept only binds to sites where there is ruptured plaque. But the platelets themselves otherwise have normal function, so regular coagulation processes should be unaffected,” he commented.

“While collagen also has a role in the coagulation process, it is more involved in atherosclerotic plaque rupture, and in animal studies, revacept was effective in preventing clot formation in large arteries but only had a small effect on bleeding,” Dr. Massberg added.

In the JAMA Cardiology article, the authors further elaborated that, when collagen is exposed during atherosclerotic plaque rupture, it binds platelet GPVI, the major platelet collagen receptor.

“Glycoprotein VI in turn mediates local platelet recruitment, activation, and aggregation. Glycoprotein VI is an attractive antiplatelet target because GPVI-mediated platelet response plays a central role during myocardial infarction and stroke but is less relevant in physiological hemostasis,” they wrote.

The researchers describe revacept as a dimeric, soluble fusion protein composed of the extracellular domain of the GPVI receptor and the human Fc-fragment. It competes with endogenous platelet GPVI for binding to exposed collagen fibers and inhibits collagen-mediated platelet adhesion and aggregation selectively at the site of plaque rupture.

In addition, revacept blocks binding of von Willebrand factor to collagen and inhibits von Willebrand factor–mediated platelet activation, they reported.

“As a lesion-directed drug, revacept does not interfere with the function of circulating platelets beyond the atherosclerotic lesion,” the authors said.

In animal studies and a phase 1 clinical trial, the drug was shown to inhibit atherothrombosis but to have little effect on systemic hemostasis or bleeding.

The current ISAR-PLASTER trial is the first study of the use of the agent for patients with coronary heart disease.

For the study, 334 patients with stable ischemic heart disease undergoing elective PCI were randomly assigned to receive a single intravenous infusion of revacept 160 mg, revacept 80 mg, or placebo prior to the start of PCI in addition to standard antithrombotic therapy.

The safety endpoint was bleeding of type 2-5, per Bleeding Academic Research Consortium (BARC) criteria, at 30 days.

Results showed no significant differences in the primary efficacy endpoint (the composite of death or myocardial injury, defined as an increase in high-sensitivity cardiac troponin T [hsTnT] to at least five times the upper limit of normal within 48 hours from randomization) between the revacept and placebo groups. The primary efficacy endpoint occurred in 24.4% of the revacept 160-mg group, 25.0% of the revacept 80-mg group, and 23.3% of the placebo group.

The high dose of revacept was associated with a small but significant reduction of high-concentration collagen-induced platelet aggregation, but adenosine 5-diphosphate–induced aggregation was not affected.

Revacept did not increase bleeding. Bleeding of BARC type 2 or higher at 30 days occurred in 5.0% of the 160-mg group, 5.9% of the 80-mg group, and 8.6% of the placebo group.

Dr. Massberg pointed out that one possible explanation for the lack of difference in the efficacy outcome was that the patients enrolled in the study were at low risk.

“The rate of major adverse cardiovascular events was very low (2.5% at 30 days), and this was a low-risk population undergoing elective PCI,” he commented.

The authors also pointed out that the five-times increase in hsTnT endpoint used in the current study has little prognostic impact.

In addition, Dr. Massberg noted that, in the stable situation, myocardial injury is mostly triggered by cholesterol embolism during PCI and side-branch occlusion due to distal plaque embolization, problems that are unlikely to respond to inhibition of GPVI-collagen interaction by revacept.

He suggested that better results may be achieved in patients with acute coronary syndrome (ACS). “In ACS patients, the myocardial injury is caused by ongoing thrombotic cascades, where the collagen-platelet interaction plays a much larger role, so in theory, this drug should show a greater effect in an ACS population.”

The researchers are now planning a larger phase 3 study in that group.

“I am still optimistic. I still believe it could work,” Dr. Massberg said. “The major aim for this study was safety and dosing. There was no difference in bleeding, so safety was supported,” he added.

The ISAR-PLASTER study was funded by the German Center for Cardiovascular Research, Deutsches Herzzentrum Munchen, the Federal Ministry of Education and Research, and advanceCOR (the manufacturer of revacept). One of the coauthors of the study is a cofounder of advanceCor.

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

A new antiplatelet drug with a completely novel mechanism of action may hold the promise of delivering the holy grail – reducing cardiac events without increasing bleeding. That is the hope behind the new class of drugs directed against the platelet collagen glycoprotein VI (GPVI) receptor.

A phase 2 trial with the first agent in this class, known as revacept (advanceCOR), showed no increase in bleeding with the product when added to standard dual-antiplatelet therapy for patients with stable ischemic heart disease undergoing elective percutaneous coronary intervention (PCI), despite the drug’s being used at a dose that has been shown to increase platelet inhibition.

Unfortunately, there was no reduction in the primary clinical efficacy endpoint, a myocardial injury surrogate, but the authors pointed out that the overall event rate was low, and they were hopeful that future trials in a higher-risk population will show efficacy.

The ISAR PLASTER study was published online on March 31 in JAMA Cardiology.

“This new drug is targeting the collagen in the extracellular matrix of atherosclerotic plaque rather than the platelets themselves. So, in theory, this agent should not cause an increase in bleeding,” study author Steffen Massberg, DrMed, said in an interview.

Dr. Massberg explained that revacept targets the binding site for platelets on collagen that is exposed on rupture of atherosclerotic plaques and is a major trigger of platelet activation.

“In contrast to aspirin and P2Y12 inhibitors, which target all platelets, revacept only binds to sites where there is ruptured plaque. But the platelets themselves otherwise have normal function, so regular coagulation processes should be unaffected,” he commented.

“While collagen also has a role in the coagulation process, it is more involved in atherosclerotic plaque rupture, and in animal studies, revacept was effective in preventing clot formation in large arteries but only had a small effect on bleeding,” Dr. Massberg added.

In the JAMA Cardiology article, the authors further elaborated that, when collagen is exposed during atherosclerotic plaque rupture, it binds platelet GPVI, the major platelet collagen receptor.

“Glycoprotein VI in turn mediates local platelet recruitment, activation, and aggregation. Glycoprotein VI is an attractive antiplatelet target because GPVI-mediated platelet response plays a central role during myocardial infarction and stroke but is less relevant in physiological hemostasis,” they wrote.

The researchers describe revacept as a dimeric, soluble fusion protein composed of the extracellular domain of the GPVI receptor and the human Fc-fragment. It competes with endogenous platelet GPVI for binding to exposed collagen fibers and inhibits collagen-mediated platelet adhesion and aggregation selectively at the site of plaque rupture.

In addition, revacept blocks binding of von Willebrand factor to collagen and inhibits von Willebrand factor–mediated platelet activation, they reported.

“As a lesion-directed drug, revacept does not interfere with the function of circulating platelets beyond the atherosclerotic lesion,” the authors said.

In animal studies and a phase 1 clinical trial, the drug was shown to inhibit atherothrombosis but to have little effect on systemic hemostasis or bleeding.

The current ISAR-PLASTER trial is the first study of the use of the agent for patients with coronary heart disease.

For the study, 334 patients with stable ischemic heart disease undergoing elective PCI were randomly assigned to receive a single intravenous infusion of revacept 160 mg, revacept 80 mg, or placebo prior to the start of PCI in addition to standard antithrombotic therapy.

The safety endpoint was bleeding of type 2-5, per Bleeding Academic Research Consortium (BARC) criteria, at 30 days.

Results showed no significant differences in the primary efficacy endpoint (the composite of death or myocardial injury, defined as an increase in high-sensitivity cardiac troponin T [hsTnT] to at least five times the upper limit of normal within 48 hours from randomization) between the revacept and placebo groups. The primary efficacy endpoint occurred in 24.4% of the revacept 160-mg group, 25.0% of the revacept 80-mg group, and 23.3% of the placebo group.

The high dose of revacept was associated with a small but significant reduction of high-concentration collagen-induced platelet aggregation, but adenosine 5-diphosphate–induced aggregation was not affected.

Revacept did not increase bleeding. Bleeding of BARC type 2 or higher at 30 days occurred in 5.0% of the 160-mg group, 5.9% of the 80-mg group, and 8.6% of the placebo group.

Dr. Massberg pointed out that one possible explanation for the lack of difference in the efficacy outcome was that the patients enrolled in the study were at low risk.

“The rate of major adverse cardiovascular events was very low (2.5% at 30 days), and this was a low-risk population undergoing elective PCI,” he commented.

The authors also pointed out that the five-times increase in hsTnT endpoint used in the current study has little prognostic impact.

In addition, Dr. Massberg noted that, in the stable situation, myocardial injury is mostly triggered by cholesterol embolism during PCI and side-branch occlusion due to distal plaque embolization, problems that are unlikely to respond to inhibition of GPVI-collagen interaction by revacept.

He suggested that better results may be achieved in patients with acute coronary syndrome (ACS). “In ACS patients, the myocardial injury is caused by ongoing thrombotic cascades, where the collagen-platelet interaction plays a much larger role, so in theory, this drug should show a greater effect in an ACS population.”

The researchers are now planning a larger phase 3 study in that group.

“I am still optimistic. I still believe it could work,” Dr. Massberg said. “The major aim for this study was safety and dosing. There was no difference in bleeding, so safety was supported,” he added.

The ISAR-PLASTER study was funded by the German Center for Cardiovascular Research, Deutsches Herzzentrum Munchen, the Federal Ministry of Education and Research, and advanceCOR (the manufacturer of revacept). One of the coauthors of the study is a cofounder of advanceCor.

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

A new antiplatelet drug with a completely novel mechanism of action may hold the promise of delivering the holy grail – reducing cardiac events without increasing bleeding. That is the hope behind the new class of drugs directed against the platelet collagen glycoprotein VI (GPVI) receptor.

A phase 2 trial with the first agent in this class, known as revacept (advanceCOR), showed no increase in bleeding with the product when added to standard dual-antiplatelet therapy for patients with stable ischemic heart disease undergoing elective percutaneous coronary intervention (PCI), despite the drug’s being used at a dose that has been shown to increase platelet inhibition.

Unfortunately, there was no reduction in the primary clinical efficacy endpoint, a myocardial injury surrogate, but the authors pointed out that the overall event rate was low, and they were hopeful that future trials in a higher-risk population will show efficacy.

The ISAR PLASTER study was published online on March 31 in JAMA Cardiology.

“This new drug is targeting the collagen in the extracellular matrix of atherosclerotic plaque rather than the platelets themselves. So, in theory, this agent should not cause an increase in bleeding,” study author Steffen Massberg, DrMed, said in an interview.

Dr. Massberg explained that revacept targets the binding site for platelets on collagen that is exposed on rupture of atherosclerotic plaques and is a major trigger of platelet activation.

“In contrast to aspirin and P2Y12 inhibitors, which target all platelets, revacept only binds to sites where there is ruptured plaque. But the platelets themselves otherwise have normal function, so regular coagulation processes should be unaffected,” he commented.

“While collagen also has a role in the coagulation process, it is more involved in atherosclerotic plaque rupture, and in animal studies, revacept was effective in preventing clot formation in large arteries but only had a small effect on bleeding,” Dr. Massberg added.

In the JAMA Cardiology article, the authors further elaborated that, when collagen is exposed during atherosclerotic plaque rupture, it binds platelet GPVI, the major platelet collagen receptor.

“Glycoprotein VI in turn mediates local platelet recruitment, activation, and aggregation. Glycoprotein VI is an attractive antiplatelet target because GPVI-mediated platelet response plays a central role during myocardial infarction and stroke but is less relevant in physiological hemostasis,” they wrote.

The researchers describe revacept as a dimeric, soluble fusion protein composed of the extracellular domain of the GPVI receptor and the human Fc-fragment. It competes with endogenous platelet GPVI for binding to exposed collagen fibers and inhibits collagen-mediated platelet adhesion and aggregation selectively at the site of plaque rupture.

In addition, revacept blocks binding of von Willebrand factor to collagen and inhibits von Willebrand factor–mediated platelet activation, they reported.

“As a lesion-directed drug, revacept does not interfere with the function of circulating platelets beyond the atherosclerotic lesion,” the authors said.

In animal studies and a phase 1 clinical trial, the drug was shown to inhibit atherothrombosis but to have little effect on systemic hemostasis or bleeding.

The current ISAR-PLASTER trial is the first study of the use of the agent for patients with coronary heart disease.

For the study, 334 patients with stable ischemic heart disease undergoing elective PCI were randomly assigned to receive a single intravenous infusion of revacept 160 mg, revacept 80 mg, or placebo prior to the start of PCI in addition to standard antithrombotic therapy.

The safety endpoint was bleeding of type 2-5, per Bleeding Academic Research Consortium (BARC) criteria, at 30 days.

Results showed no significant differences in the primary efficacy endpoint (the composite of death or myocardial injury, defined as an increase in high-sensitivity cardiac troponin T [hsTnT] to at least five times the upper limit of normal within 48 hours from randomization) between the revacept and placebo groups. The primary efficacy endpoint occurred in 24.4% of the revacept 160-mg group, 25.0% of the revacept 80-mg group, and 23.3% of the placebo group.

The high dose of revacept was associated with a small but significant reduction of high-concentration collagen-induced platelet aggregation, but adenosine 5-diphosphate–induced aggregation was not affected.

Revacept did not increase bleeding. Bleeding of BARC type 2 or higher at 30 days occurred in 5.0% of the 160-mg group, 5.9% of the 80-mg group, and 8.6% of the placebo group.

Dr. Massberg pointed out that one possible explanation for the lack of difference in the efficacy outcome was that the patients enrolled in the study were at low risk.

“The rate of major adverse cardiovascular events was very low (2.5% at 30 days), and this was a low-risk population undergoing elective PCI,” he commented.

The authors also pointed out that the five-times increase in hsTnT endpoint used in the current study has little prognostic impact.

In addition, Dr. Massberg noted that, in the stable situation, myocardial injury is mostly triggered by cholesterol embolism during PCI and side-branch occlusion due to distal plaque embolization, problems that are unlikely to respond to inhibition of GPVI-collagen interaction by revacept.

He suggested that better results may be achieved in patients with acute coronary syndrome (ACS). “In ACS patients, the myocardial injury is caused by ongoing thrombotic cascades, where the collagen-platelet interaction plays a much larger role, so in theory, this drug should show a greater effect in an ACS population.”

The researchers are now planning a larger phase 3 study in that group.

“I am still optimistic. I still believe it could work,” Dr. Massberg said. “The major aim for this study was safety and dosing. There was no difference in bleeding, so safety was supported,” he added.

The ISAR-PLASTER study was funded by the German Center for Cardiovascular Research, Deutsches Herzzentrum Munchen, the Federal Ministry of Education and Research, and advanceCOR (the manufacturer of revacept). One of the coauthors of the study is a cofounder of advanceCor.

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

The incidence of venous thromboembolism (VTE) in nonhospitalized patients with COVID-19 was not significantly different from patients without the infectious disease, according to a new study published in JAMA Internal Medicine.

Design Cells/Getty Images

National Institutes of Health guidelines recommend blood thinners to prevent blood clots in patients hospitalized with COVID-19. However, the new study provides more insight on the best treatment approach for COVID-19 outpatients.

“[COVID-19’s] rapid global progression and impact has caused us to make and modify treatment decisions at a pace that we never have in modern medicine,” study author Nareg Roubinian, MD, an investigator at Kaiser Permanente, Oakland, Calif., said in an interview.

“As with other potential therapies for COVID-19, blood thinners need to be prospectively studied in a clinical trial to determine if they improve patient outcomes,” Dr. Roubinian added.

The increased risk of blood clots in patients hospitalized with COVID-19 has been a major issue throughout the pandemic. In fact, one study published in November 2020 found that more than half of patients hospitalized with the illness have prothrombotic antiphospholipid (aPL) autoantibodies in their blood, which could contribute to venous and arterial thromboembolism.

Although it was clear many hospitalized patients diagnosed with COVID-19 were developing more clots, researchers of the current study were not sure if this trend would also be seen in outpatients.

“Most people with COVID-19 do not need to be hospitalized, and we needed to know how often patients outside the hospital were having blood clots,” said Dr. Roubinian.

For the study, Dr. Roubinian and colleagues examined data on 220,588 patients who were members of Kaiser Permanente Northern California health plan and were tested for COVID-19 between Feb. 25 and Aug. 31, 2020. They then reported on the 30-day incidence of outpatient and hospital-associated blood clots following the COVID-19 diagnosis. Patients who were asymptomatic at the time of testing or had received anticoagulants within the last year were excluded.

“We knew from other studies that patients with COVID-19 often get sicker in the first few weeks after infection. What we didn’t know was whether COVID-19 patients were developing blood clots but not pneumonia or were developing blood clots at the same time as they developed pneumonia,” said Dr. Roubinian, an intensive care doctor with the Permanente Medical Group in Oakland, Calif. “Following the patients for 30 days allowed us to focus on the time period from infection to when blood clots were most likely to develop.”

Researchers found that of the cohort who took the COVID-19 test, 11.8% had a positive result. Within 30 days of the COVID-19 test, 0.8% of patients with a positive result were diagnosed with VTE compared to 0.5% of those who received a negative test result. They also found that viral testing took place in an outpatient setting for 59.1% of the patients with a positive viral test who later developed VTE. Of those patients, 76.1% had to be hospitalized.

Dr. Roubinian said he was surprised to see that the blood clotting in outpatients with COVID-19 was similar in frequency to what he saw in patients without the infection.

“Our findings suggest that blood clots do occur in COVID-19 patients but not on a scale where we need to put all or many COVID outpatients on blood thinners,” he said. “As with other potential therapies for COVID-19, blood thinners need to be prospectively studied in a clinical trial to determine if they improve patient outcomes.”

In December 2020, three trials investigating the risk and benefits of increased levels of anticoagulation in hospitalized COVID-19 patients were paused because of safety issues. The trials would have enrolled critically ill COVID-19 patients for whom therapeutic doses of anticoagulation drugs showed no benefit.

Anticoagulants are associated with bleeding risks, including prolonged nosebleeds and vomiting or coughing up blood.

Instead of prescribing the routine use of thromboprophylactic drugs to COVID-19 outpatients, Dr. Roubinian believes it would be helpful to learn how to determine whether a patient at risk of becoming sick or being hospitalized would benefit from being treated with such drugs.

Dr. Roubinian reported receiving grants from the National Institutes of Health and the National Heart, Lung, and Blood Institute during the conduct of the study.
 

The incidence of venous thromboembolism (VTE) in nonhospitalized patients with COVID-19 was not significantly different from patients without the infectious disease, according to a new study published in JAMA Internal Medicine.

Design Cells/Getty Images

National Institutes of Health guidelines recommend blood thinners to prevent blood clots in patients hospitalized with COVID-19. However, the new study provides more insight on the best treatment approach for COVID-19 outpatients.

“[COVID-19’s] rapid global progression and impact has caused us to make and modify treatment decisions at a pace that we never have in modern medicine,” study author Nareg Roubinian, MD, an investigator at Kaiser Permanente, Oakland, Calif., said in an interview.

“As with other potential therapies for COVID-19, blood thinners need to be prospectively studied in a clinical trial to determine if they improve patient outcomes,” Dr. Roubinian added.

The increased risk of blood clots in patients hospitalized with COVID-19 has been a major issue throughout the pandemic. In fact, one study published in November 2020 found that more than half of patients hospitalized with the illness have prothrombotic antiphospholipid (aPL) autoantibodies in their blood, which could contribute to venous and arterial thromboembolism.

Although it was clear many hospitalized patients diagnosed with COVID-19 were developing more clots, researchers of the current study were not sure if this trend would also be seen in outpatients.

“Most people with COVID-19 do not need to be hospitalized, and we needed to know how often patients outside the hospital were having blood clots,” said Dr. Roubinian.

For the study, Dr. Roubinian and colleagues examined data on 220,588 patients who were members of Kaiser Permanente Northern California health plan and were tested for COVID-19 between Feb. 25 and Aug. 31, 2020. They then reported on the 30-day incidence of outpatient and hospital-associated blood clots following the COVID-19 diagnosis. Patients who were asymptomatic at the time of testing or had received anticoagulants within the last year were excluded.

“We knew from other studies that patients with COVID-19 often get sicker in the first few weeks after infection. What we didn’t know was whether COVID-19 patients were developing blood clots but not pneumonia or were developing blood clots at the same time as they developed pneumonia,” said Dr. Roubinian, an intensive care doctor with the Permanente Medical Group in Oakland, Calif. “Following the patients for 30 days allowed us to focus on the time period from infection to when blood clots were most likely to develop.”

Researchers found that of the cohort who took the COVID-19 test, 11.8% had a positive result. Within 30 days of the COVID-19 test, 0.8% of patients with a positive result were diagnosed with VTE compared to 0.5% of those who received a negative test result. They also found that viral testing took place in an outpatient setting for 59.1% of the patients with a positive viral test who later developed VTE. Of those patients, 76.1% had to be hospitalized.

Dr. Roubinian said he was surprised to see that the blood clotting in outpatients with COVID-19 was similar in frequency to what he saw in patients without the infection.

“Our findings suggest that blood clots do occur in COVID-19 patients but not on a scale where we need to put all or many COVID outpatients on blood thinners,” he said. “As with other potential therapies for COVID-19, blood thinners need to be prospectively studied in a clinical trial to determine if they improve patient outcomes.”

In December 2020, three trials investigating the risk and benefits of increased levels of anticoagulation in hospitalized COVID-19 patients were paused because of safety issues. The trials would have enrolled critically ill COVID-19 patients for whom therapeutic doses of anticoagulation drugs showed no benefit.

Anticoagulants are associated with bleeding risks, including prolonged nosebleeds and vomiting or coughing up blood.

Instead of prescribing the routine use of thromboprophylactic drugs to COVID-19 outpatients, Dr. Roubinian believes it would be helpful to learn how to determine whether a patient at risk of becoming sick or being hospitalized would benefit from being treated with such drugs.

Dr. Roubinian reported receiving grants from the National Institutes of Health and the National Heart, Lung, and Blood Institute during the conduct of the study.
 

The incidence of venous thromboembolism (VTE) in nonhospitalized patients with COVID-19 was not significantly different from patients without the infectious disease, according to a new study published in JAMA Internal Medicine.

Design Cells/Getty Images

National Institutes of Health guidelines recommend blood thinners to prevent blood clots in patients hospitalized with COVID-19. However, the new study provides more insight on the best treatment approach for COVID-19 outpatients.

“[COVID-19’s] rapid global progression and impact has caused us to make and modify treatment decisions at a pace that we never have in modern medicine,” study author Nareg Roubinian, MD, an investigator at Kaiser Permanente, Oakland, Calif., said in an interview.

“As with other potential therapies for COVID-19, blood thinners need to be prospectively studied in a clinical trial to determine if they improve patient outcomes,” Dr. Roubinian added.

The increased risk of blood clots in patients hospitalized with COVID-19 has been a major issue throughout the pandemic. In fact, one study published in November 2020 found that more than half of patients hospitalized with the illness have prothrombotic antiphospholipid (aPL) autoantibodies in their blood, which could contribute to venous and arterial thromboembolism.

Although it was clear many hospitalized patients diagnosed with COVID-19 were developing more clots, researchers of the current study were not sure if this trend would also be seen in outpatients.

“Most people with COVID-19 do not need to be hospitalized, and we needed to know how often patients outside the hospital were having blood clots,” said Dr. Roubinian.

For the study, Dr. Roubinian and colleagues examined data on 220,588 patients who were members of Kaiser Permanente Northern California health plan and were tested for COVID-19 between Feb. 25 and Aug. 31, 2020. They then reported on the 30-day incidence of outpatient and hospital-associated blood clots following the COVID-19 diagnosis. Patients who were asymptomatic at the time of testing or had received anticoagulants within the last year were excluded.

“We knew from other studies that patients with COVID-19 often get sicker in the first few weeks after infection. What we didn’t know was whether COVID-19 patients were developing blood clots but not pneumonia or were developing blood clots at the same time as they developed pneumonia,” said Dr. Roubinian, an intensive care doctor with the Permanente Medical Group in Oakland, Calif. “Following the patients for 30 days allowed us to focus on the time period from infection to when blood clots were most likely to develop.”

Researchers found that of the cohort who took the COVID-19 test, 11.8% had a positive result. Within 30 days of the COVID-19 test, 0.8% of patients with a positive result were diagnosed with VTE compared to 0.5% of those who received a negative test result. They also found that viral testing took place in an outpatient setting for 59.1% of the patients with a positive viral test who later developed VTE. Of those patients, 76.1% had to be hospitalized.

Dr. Roubinian said he was surprised to see that the blood clotting in outpatients with COVID-19 was similar in frequency to what he saw in patients without the infection.

“Our findings suggest that blood clots do occur in COVID-19 patients but not on a scale where we need to put all or many COVID outpatients on blood thinners,” he said. “As with other potential therapies for COVID-19, blood thinners need to be prospectively studied in a clinical trial to determine if they improve patient outcomes.”

In December 2020, three trials investigating the risk and benefits of increased levels of anticoagulation in hospitalized COVID-19 patients were paused because of safety issues. The trials would have enrolled critically ill COVID-19 patients for whom therapeutic doses of anticoagulation drugs showed no benefit.

Anticoagulants are associated with bleeding risks, including prolonged nosebleeds and vomiting or coughing up blood.

Instead of prescribing the routine use of thromboprophylactic drugs to COVID-19 outpatients, Dr. Roubinian believes it would be helpful to learn how to determine whether a patient at risk of becoming sick or being hospitalized would benefit from being treated with such drugs.

Dr. Roubinian reported receiving grants from the National Institutes of Health and the National Heart, Lung, and Blood Institute during the conduct of the study.
 

The European Medicines Agency continues to reassure the public about the safety of the AstraZeneca COVID-19 vaccine, although several countries have imposed new restrictions on the product, owing to its link to a rare clotting disorder.

Use of the vaccine has been suspended for individuals younger than 55 or 60 years in several European countries and in Canada after reports of a prothrombotic disorder and thrombocytopenia, mainly in younger individuals.

Now, more information on the prothrombotic disorder has become available. The vaccine appears to be linked to a condition that clinically resembles heparin-induced thrombocytopenia (HIT) and that occurs mainly in younger women.

Researchers have described clinical and laboratory details of nine patients from Germany and Austria who developed this condition 4-16 days after receiving the AstraZeneca vaccine in a preprint article published March 28, 2021, on Research Square.

They found that serum from four patients who were tested showed platelet-activating antibodies directed against platelet factor 4 (PF4), similar to what is seen in HIT.

They are proposing naming the condition “vaccine-induced prothrombotic immune thrombocytopenia (VIPIT)” to avoid confusion with HIT.

At a press conference March 31, the EMA said its ongoing review of the situation “has not identified any specific risk factors, such as age, gender, or a previous medical history of clotting disorders, for these very rare events. A causal link with the vaccine is not proven but is possible, and further analysis is continuing.”

A statement from the agency noted: “EMA is of the view that the benefits of the AstraZeneca vaccine in preventing COVID-19, with its associated risk of hospitalization and death, outweigh the risks of side effects.”

But it added: “Vaccinated people should be aware of the remote possibility of these very rare types of blood clots occurring. If they have symptoms suggestive of clotting problems as described in the product information, they should seek immediate medical attention and inform health care professionals of their recent vaccination.”
 

VIPIT study

In the Research Square preprint article, a group led by Andreas Greinacher, MD, professor of transfusion medicine at the Greifswald (Germany) University Clinic, reported on clinical and laboratory features of nine patients (eight of whom were women) in Germany and Austria who developed thrombosis and thrombocytopenia after they received the AstraZeneca vaccine.

The researchers explained that they investigated whether these patients could have a prothrombotic disorder caused by platelet-activating antibodies directed against PF4, which is known to be caused by heparin and sometimes environmental triggers.

The nine patients were aged 22-49 years and presented with thrombosis beginning 4-16 days post vaccination. Seven patients had cerebral venous thrombosis (CVT), one had pulmonary embolism, and one had splanchnic vein thrombosis and CVT. Four patients died. None had received heparin prior to symptom onset.

Serum from four patients was tested for anti-PF4/heparin antibodies, and all four tested strongly positive. All four also tested strongly positive on platelet activation assay for the presence of PF4 independently of heparin.

The authors noted that it has been recognized that triggers other than heparin, including some infections, can rarely cause a disorder that strongly resembles HIT. These cases have been referred to as spontaneous HIT syndrome.

They said that their current findings have several important clinical implications.

“Clinicians should be aware that onset of (venous or arterial) thrombosis particularly at unusual sites such as in the brain or abdomen and thrombocytopenia beginning approximately 5-14 days after vaccination can represent a rare adverse effect of preceding COVID-19 vaccination,” they wrote. To date, this has only been reported with the AstraZeneca vaccine.

They pointed out that enzyme immunoassays for HIT are widely available and can be used to investigate for potential postvaccination anti-PF4 antibody–associated thrombocytopenia/thrombosis. For such patients, referral should be made to a laboratory that performs platelet-activation assays.

Although this syndrome differs from typical HIT, the researchers noted that at least one patient showed strong platelet activation in the presence of heparin. They thus recommended therapy with nonheparin anticoagulants, such as the direct oral anticoagulants.

They also wrote that high-dose intravenous immunoglobulin has been shown to be effective for treating severe HIT and could also be an important treatment adjunct for patients who develop life-threatening thrombotic events, such as cerebral vein sinus thrombosis (CVST), after being vaccinated.
 

EMA data to date

Updated data, reported at the EMA press briefing on March 31, indicate that 62 cases of CVST have been reported worldwide (44 from the European Union). These data may not yet include all the German cases.

Peter Arlett, MD, head of pharmacovigilance and epidemiology at the EMA, said there were more cases than expected in the 2-week window after vaccination among patients younger than 60 and that health care professionals should be alert to features of this condition, including headache and blurred vision.

He suggested that the higher rate of the condition among younger women may reflect the population that received this vaccine, because initially, the vaccine was not recommended for older people in many countries and was targeted toward younger health care workers, who were mainly women.

The German regulatory agency, the Paul Ehrlich Institute, reported this week that it has now registered 31 cases of CVST among nearly 2.7 million people who had received the vaccine in Germany. Of these patients, 19 also were found to have a deficiency of blood platelets or thrombocytopenia. Nine of the affected patients died. All but two of the cases occurred in women aged 20-63 years. The two men were aged 36 and 57 years.

These data have prompted the German authorities to limit use of the AstraZeneca vaccine to those aged 60 years and older. Even before this decision, senior clinicians in Germany had been urging a change in the vaccination recommendations.

For example, Bernd Salzberger, MD, head of infectious diseases, University Hospital Regensburg (Germany), told the Science Media Center: “In women, a complicated course of COVID disease is less common from the start and is so rare in younger women that the chance of avoiding a fatal course through vaccination in women without comorbidities is of the same order of magnitude as the risk of this rare side effect.”

Sandra Ciesek, MD, a virologist at Goethe University, Frankfurt, Germany, told the journal Science: “The argument I keep hearing is that the risk-benefit ratio is still positive. But we do not have just one vaccine, we have several. So, restricting the AstraZeneca vaccine to older people makes sense to me, and it does not waste any doses.”
 

Concerns put in perspective

Commenting of the latest developments, thrombosis expert Saskia Middeldorp, MD, head of internal medicine at Radboud University Medical Center, Nijmegen, the Netherlands, said it was vitally important that these concerns be put in perspective and that the vaccination program with the AstraZeneca product continue.

“There are some concerning reports about very rare blood clotting disorders and low platelet counts possibly associated with the AstraZeneca vaccine. Groups from Germany and Norway have identified a syndrome similar to HIT, which seems to explain the cause of this very rare side effect,” Dr. Middeldorp noted.

“But with such a high pressure from the virus and many countries now going into a third wave of infection, anything that might slow down vaccination rates will cause much more harm than good,” she warned.

Dr. Middeldorp believes the incidence of this HIT-type syndrome linked to the vaccine is about 1-2 per million. “These are estimates based on the number of reports of this side effect and denominators from the U.K. and EU populations,” she explained. However, Germany has restricted the vaccine on the basis of German data, which appear to show higher rates of the condition. It is not known why the rates are higher in Germany.

“The European Medicines Agency is looking at this very closely. Their statement is quite clear. There is no foundation for changing policy on vaccination,” Dr. Middeldorp stated.

She cautioned that these reports were reducing confidence in the AstraZeneca vaccine, particularly among young people, which she said was causing “a major setback” for the vaccination program.

Noting that everything must be viewed in the context of this severe pandemic, Dr. Middeldorp emphasized that the benefit of the vaccine outweighed any risk, even among young people.

“To those who may be hesitating to have the vaccine as they don’t think they are at high risk of severe COVID infection, I would say there are a lot of young people in the ICU at present with COVID, and your chance of a severe COVID illness is far higher than the 1 or 2 in a million risk of a severe reaction to the vaccine,” she stated.

Dr. Greinacher has received grants and nonfinancial support from Aspen, Boehringer Ingelheim, Merck Sharp & Dohme, Bristol-Myers Squibb, Paringenix, Bayer Healthcare, Gore, Rovi, Sagent, and Biomarin/Prosensa; personal fees from Aspen, Boehringer Ingelheim, Merck Sharp & Dohme, Macopharma, Bristol-Myers Squibb, Chromatec, and Instrumentation Laboratory; and nonfinancial support from Boehringer Ingelheim, Portola, Ergomed, and GTH outside the submitted work.

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

The European Medicines Agency continues to reassure the public about the safety of the AstraZeneca COVID-19 vaccine, although several countries have imposed new restrictions on the product, owing to its link to a rare clotting disorder.

Use of the vaccine has been suspended for individuals younger than 55 or 60 years in several European countries and in Canada after reports of a prothrombotic disorder and thrombocytopenia, mainly in younger individuals.

Now, more information on the prothrombotic disorder has become available. The vaccine appears to be linked to a condition that clinically resembles heparin-induced thrombocytopenia (HIT) and that occurs mainly in younger women.

Researchers have described clinical and laboratory details of nine patients from Germany and Austria who developed this condition 4-16 days after receiving the AstraZeneca vaccine in a preprint article published March 28, 2021, on Research Square.

They found that serum from four patients who were tested showed platelet-activating antibodies directed against platelet factor 4 (PF4), similar to what is seen in HIT.

They are proposing naming the condition “vaccine-induced prothrombotic immune thrombocytopenia (VIPIT)” to avoid confusion with HIT.

At a press conference March 31, the EMA said its ongoing review of the situation “has not identified any specific risk factors, such as age, gender, or a previous medical history of clotting disorders, for these very rare events. A causal link with the vaccine is not proven but is possible, and further analysis is continuing.”

A statement from the agency noted: “EMA is of the view that the benefits of the AstraZeneca vaccine in preventing COVID-19, with its associated risk of hospitalization and death, outweigh the risks of side effects.”

But it added: “Vaccinated people should be aware of the remote possibility of these very rare types of blood clots occurring. If they have symptoms suggestive of clotting problems as described in the product information, they should seek immediate medical attention and inform health care professionals of their recent vaccination.”
 

VIPIT study

In the Research Square preprint article, a group led by Andreas Greinacher, MD, professor of transfusion medicine at the Greifswald (Germany) University Clinic, reported on clinical and laboratory features of nine patients (eight of whom were women) in Germany and Austria who developed thrombosis and thrombocytopenia after they received the AstraZeneca vaccine.

The researchers explained that they investigated whether these patients could have a prothrombotic disorder caused by platelet-activating antibodies directed against PF4, which is known to be caused by heparin and sometimes environmental triggers.

The nine patients were aged 22-49 years and presented with thrombosis beginning 4-16 days post vaccination. Seven patients had cerebral venous thrombosis (CVT), one had pulmonary embolism, and one had splanchnic vein thrombosis and CVT. Four patients died. None had received heparin prior to symptom onset.

Serum from four patients was tested for anti-PF4/heparin antibodies, and all four tested strongly positive. All four also tested strongly positive on platelet activation assay for the presence of PF4 independently of heparin.

The authors noted that it has been recognized that triggers other than heparin, including some infections, can rarely cause a disorder that strongly resembles HIT. These cases have been referred to as spontaneous HIT syndrome.

They said that their current findings have several important clinical implications.

“Clinicians should be aware that onset of (venous or arterial) thrombosis particularly at unusual sites such as in the brain or abdomen and thrombocytopenia beginning approximately 5-14 days after vaccination can represent a rare adverse effect of preceding COVID-19 vaccination,” they wrote. To date, this has only been reported with the AstraZeneca vaccine.

They pointed out that enzyme immunoassays for HIT are widely available and can be used to investigate for potential postvaccination anti-PF4 antibody–associated thrombocytopenia/thrombosis. For such patients, referral should be made to a laboratory that performs platelet-activation assays.

Although this syndrome differs from typical HIT, the researchers noted that at least one patient showed strong platelet activation in the presence of heparin. They thus recommended therapy with nonheparin anticoagulants, such as the direct oral anticoagulants.

They also wrote that high-dose intravenous immunoglobulin has been shown to be effective for treating severe HIT and could also be an important treatment adjunct for patients who develop life-threatening thrombotic events, such as cerebral vein sinus thrombosis (CVST), after being vaccinated.
 

EMA data to date

Updated data, reported at the EMA press briefing on March 31, indicate that 62 cases of CVST have been reported worldwide (44 from the European Union). These data may not yet include all the German cases.

Peter Arlett, MD, head of pharmacovigilance and epidemiology at the EMA, said there were more cases than expected in the 2-week window after vaccination among patients younger than 60 and that health care professionals should be alert to features of this condition, including headache and blurred vision.

He suggested that the higher rate of the condition among younger women may reflect the population that received this vaccine, because initially, the vaccine was not recommended for older people in many countries and was targeted toward younger health care workers, who were mainly women.

The German regulatory agency, the Paul Ehrlich Institute, reported this week that it has now registered 31 cases of CVST among nearly 2.7 million people who had received the vaccine in Germany. Of these patients, 19 also were found to have a deficiency of blood platelets or thrombocytopenia. Nine of the affected patients died. All but two of the cases occurred in women aged 20-63 years. The two men were aged 36 and 57 years.

These data have prompted the German authorities to limit use of the AstraZeneca vaccine to those aged 60 years and older. Even before this decision, senior clinicians in Germany had been urging a change in the vaccination recommendations.

For example, Bernd Salzberger, MD, head of infectious diseases, University Hospital Regensburg (Germany), told the Science Media Center: “In women, a complicated course of COVID disease is less common from the start and is so rare in younger women that the chance of avoiding a fatal course through vaccination in women without comorbidities is of the same order of magnitude as the risk of this rare side effect.”

Sandra Ciesek, MD, a virologist at Goethe University, Frankfurt, Germany, told the journal Science: “The argument I keep hearing is that the risk-benefit ratio is still positive. But we do not have just one vaccine, we have several. So, restricting the AstraZeneca vaccine to older people makes sense to me, and it does not waste any doses.”
 

Concerns put in perspective

Commenting of the latest developments, thrombosis expert Saskia Middeldorp, MD, head of internal medicine at Radboud University Medical Center, Nijmegen, the Netherlands, said it was vitally important that these concerns be put in perspective and that the vaccination program with the AstraZeneca product continue.

“There are some concerning reports about very rare blood clotting disorders and low platelet counts possibly associated with the AstraZeneca vaccine. Groups from Germany and Norway have identified a syndrome similar to HIT, which seems to explain the cause of this very rare side effect,” Dr. Middeldorp noted.

“But with such a high pressure from the virus and many countries now going into a third wave of infection, anything that might slow down vaccination rates will cause much more harm than good,” she warned.

Dr. Middeldorp believes the incidence of this HIT-type syndrome linked to the vaccine is about 1-2 per million. “These are estimates based on the number of reports of this side effect and denominators from the U.K. and EU populations,” she explained. However, Germany has restricted the vaccine on the basis of German data, which appear to show higher rates of the condition. It is not known why the rates are higher in Germany.

“The European Medicines Agency is looking at this very closely. Their statement is quite clear. There is no foundation for changing policy on vaccination,” Dr. Middeldorp stated.

She cautioned that these reports were reducing confidence in the AstraZeneca vaccine, particularly among young people, which she said was causing “a major setback” for the vaccination program.

Noting that everything must be viewed in the context of this severe pandemic, Dr. Middeldorp emphasized that the benefit of the vaccine outweighed any risk, even among young people.

“To those who may be hesitating to have the vaccine as they don’t think they are at high risk of severe COVID infection, I would say there are a lot of young people in the ICU at present with COVID, and your chance of a severe COVID illness is far higher than the 1 or 2 in a million risk of a severe reaction to the vaccine,” she stated.

Dr. Greinacher has received grants and nonfinancial support from Aspen, Boehringer Ingelheim, Merck Sharp & Dohme, Bristol-Myers Squibb, Paringenix, Bayer Healthcare, Gore, Rovi, Sagent, and Biomarin/Prosensa; personal fees from Aspen, Boehringer Ingelheim, Merck Sharp & Dohme, Macopharma, Bristol-Myers Squibb, Chromatec, and Instrumentation Laboratory; and nonfinancial support from Boehringer Ingelheim, Portola, Ergomed, and GTH outside the submitted work.

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

The European Medicines Agency continues to reassure the public about the safety of the AstraZeneca COVID-19 vaccine, although several countries have imposed new restrictions on the product, owing to its link to a rare clotting disorder.

Use of the vaccine has been suspended for individuals younger than 55 or 60 years in several European countries and in Canada after reports of a prothrombotic disorder and thrombocytopenia, mainly in younger individuals.

Now, more information on the prothrombotic disorder has become available. The vaccine appears to be linked to a condition that clinically resembles heparin-induced thrombocytopenia (HIT) and that occurs mainly in younger women.

Researchers have described clinical and laboratory details of nine patients from Germany and Austria who developed this condition 4-16 days after receiving the AstraZeneca vaccine in a preprint article published March 28, 2021, on Research Square.

They found that serum from four patients who were tested showed platelet-activating antibodies directed against platelet factor 4 (PF4), similar to what is seen in HIT.

They are proposing naming the condition “vaccine-induced prothrombotic immune thrombocytopenia (VIPIT)” to avoid confusion with HIT.

At a press conference March 31, the EMA said its ongoing review of the situation “has not identified any specific risk factors, such as age, gender, or a previous medical history of clotting disorders, for these very rare events. A causal link with the vaccine is not proven but is possible, and further analysis is continuing.”

A statement from the agency noted: “EMA is of the view that the benefits of the AstraZeneca vaccine in preventing COVID-19, with its associated risk of hospitalization and death, outweigh the risks of side effects.”

But it added: “Vaccinated people should be aware of the remote possibility of these very rare types of blood clots occurring. If they have symptoms suggestive of clotting problems as described in the product information, they should seek immediate medical attention and inform health care professionals of their recent vaccination.”
 

VIPIT study

In the Research Square preprint article, a group led by Andreas Greinacher, MD, professor of transfusion medicine at the Greifswald (Germany) University Clinic, reported on clinical and laboratory features of nine patients (eight of whom were women) in Germany and Austria who developed thrombosis and thrombocytopenia after they received the AstraZeneca vaccine.

The researchers explained that they investigated whether these patients could have a prothrombotic disorder caused by platelet-activating antibodies directed against PF4, which is known to be caused by heparin and sometimes environmental triggers.

The nine patients were aged 22-49 years and presented with thrombosis beginning 4-16 days post vaccination. Seven patients had cerebral venous thrombosis (CVT), one had pulmonary embolism, and one had splanchnic vein thrombosis and CVT. Four patients died. None had received heparin prior to symptom onset.

Serum from four patients was tested for anti-PF4/heparin antibodies, and all four tested strongly positive. All four also tested strongly positive on platelet activation assay for the presence of PF4 independently of heparin.

The authors noted that it has been recognized that triggers other than heparin, including some infections, can rarely cause a disorder that strongly resembles HIT. These cases have been referred to as spontaneous HIT syndrome.

They said that their current findings have several important clinical implications.

“Clinicians should be aware that onset of (venous or arterial) thrombosis particularly at unusual sites such as in the brain or abdomen and thrombocytopenia beginning approximately 5-14 days after vaccination can represent a rare adverse effect of preceding COVID-19 vaccination,” they wrote. To date, this has only been reported with the AstraZeneca vaccine.

They pointed out that enzyme immunoassays for HIT are widely available and can be used to investigate for potential postvaccination anti-PF4 antibody–associated thrombocytopenia/thrombosis. For such patients, referral should be made to a laboratory that performs platelet-activation assays.

Although this syndrome differs from typical HIT, the researchers noted that at least one patient showed strong platelet activation in the presence of heparin. They thus recommended therapy with nonheparin anticoagulants, such as the direct oral anticoagulants.

They also wrote that high-dose intravenous immunoglobulin has been shown to be effective for treating severe HIT and could also be an important treatment adjunct for patients who develop life-threatening thrombotic events, such as cerebral vein sinus thrombosis (CVST), after being vaccinated.
 

EMA data to date

Updated data, reported at the EMA press briefing on March 31, indicate that 62 cases of CVST have been reported worldwide (44 from the European Union). These data may not yet include all the German cases.

Peter Arlett, MD, head of pharmacovigilance and epidemiology at the EMA, said there were more cases than expected in the 2-week window after vaccination among patients younger than 60 and that health care professionals should be alert to features of this condition, including headache and blurred vision.

He suggested that the higher rate of the condition among younger women may reflect the population that received this vaccine, because initially, the vaccine was not recommended for older people in many countries and was targeted toward younger health care workers, who were mainly women.

The German regulatory agency, the Paul Ehrlich Institute, reported this week that it has now registered 31 cases of CVST among nearly 2.7 million people who had received the vaccine in Germany. Of these patients, 19 also were found to have a deficiency of blood platelets or thrombocytopenia. Nine of the affected patients died. All but two of the cases occurred in women aged 20-63 years. The two men were aged 36 and 57 years.

These data have prompted the German authorities to limit use of the AstraZeneca vaccine to those aged 60 years and older. Even before this decision, senior clinicians in Germany had been urging a change in the vaccination recommendations.

For example, Bernd Salzberger, MD, head of infectious diseases, University Hospital Regensburg (Germany), told the Science Media Center: “In women, a complicated course of COVID disease is less common from the start and is so rare in younger women that the chance of avoiding a fatal course through vaccination in women without comorbidities is of the same order of magnitude as the risk of this rare side effect.”

Sandra Ciesek, MD, a virologist at Goethe University, Frankfurt, Germany, told the journal Science: “The argument I keep hearing is that the risk-benefit ratio is still positive. But we do not have just one vaccine, we have several. So, restricting the AstraZeneca vaccine to older people makes sense to me, and it does not waste any doses.”
 

Concerns put in perspective

Commenting of the latest developments, thrombosis expert Saskia Middeldorp, MD, head of internal medicine at Radboud University Medical Center, Nijmegen, the Netherlands, said it was vitally important that these concerns be put in perspective and that the vaccination program with the AstraZeneca product continue.

“There are some concerning reports about very rare blood clotting disorders and low platelet counts possibly associated with the AstraZeneca vaccine. Groups from Germany and Norway have identified a syndrome similar to HIT, which seems to explain the cause of this very rare side effect,” Dr. Middeldorp noted.

“But with such a high pressure from the virus and many countries now going into a third wave of infection, anything that might slow down vaccination rates will cause much more harm than good,” she warned.

Dr. Middeldorp believes the incidence of this HIT-type syndrome linked to the vaccine is about 1-2 per million. “These are estimates based on the number of reports of this side effect and denominators from the U.K. and EU populations,” she explained. However, Germany has restricted the vaccine on the basis of German data, which appear to show higher rates of the condition. It is not known why the rates are higher in Germany.

“The European Medicines Agency is looking at this very closely. Their statement is quite clear. There is no foundation for changing policy on vaccination,” Dr. Middeldorp stated.

She cautioned that these reports were reducing confidence in the AstraZeneca vaccine, particularly among young people, which she said was causing “a major setback” for the vaccination program.

Noting that everything must be viewed in the context of this severe pandemic, Dr. Middeldorp emphasized that the benefit of the vaccine outweighed any risk, even among young people.

“To those who may be hesitating to have the vaccine as they don’t think they are at high risk of severe COVID infection, I would say there are a lot of young people in the ICU at present with COVID, and your chance of a severe COVID illness is far higher than the 1 or 2 in a million risk of a severe reaction to the vaccine,” she stated.

Dr. Greinacher has received grants and nonfinancial support from Aspen, Boehringer Ingelheim, Merck Sharp & Dohme, Bristol-Myers Squibb, Paringenix, Bayer Healthcare, Gore, Rovi, Sagent, and Biomarin/Prosensa; personal fees from Aspen, Boehringer Ingelheim, Merck Sharp & Dohme, Macopharma, Bristol-Myers Squibb, Chromatec, and Instrumentation Laboratory; and nonfinancial support from Boehringer Ingelheim, Portola, Ergomed, and GTH outside the submitted work.

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

Direct oral anticoagulants (DOACs) are used in about 1% of patients undergoing surgical mechanical aortic and mitral valve replacement, but in up to 6% of surgical bioprosthetic valve replacements, according to registry data presented at CRT 2021.

In an analysis of the Society of Thoracic Surgery (STS) registry during 2014-2017, DOAC use increased steadily among those undergoing surgical bioprosthetic valve replacement, reaching a number that is potentially clinically significant, according to Ankur Kalra, MD, an interventional cardiologist at Akron General Hospital who has an academic appointment at the Cleveland Clinic.

There was no increase in the use of DOACs observed among patients undergoing mechanical valve replacement, “but even if the number is 1%, they should probably not be used at all until we accrue more data,” Dr. Kalra said.
 

DOACs discouraged in patients with mechanical or bioprosthetic valves

In Food and Drug Administration labeling, DOACs are contraindicated or not recommended. This can be traced to the randomized RE-ALIGN trial, which was stopped prematurely due to evidence of harm from a DOAC, according to Dr. Kalra.

In RE-ALIGN, which enrolled patients undergoing mechanical aortic or mitral valve replacement, dabigatran was associated not only with more bleeding events than warfarin, but also more thromboembolic events.

There are no randomized data comparing the factor Xa inhibitors rivaroxaban or apixaban to warfarin in heart valve surgery, but Dr. Kalra noted cautionary language is found in the labeling of both, “perhaps due to the RE-ALIGN data.”
 

Registry shows trends in prescribing

In the STS registry data, 193 (1.1%) of the 18,142 patients undergoing mechanical aortic valve surgery, 139 (1.0%) of the 13,942 patients undergoing mechanical mitral valve surgery, 5,625 (4.7%) of the 116,203 patients undergoing aortic bioprosthetic aortic valve surgery, and 2,180 (5.9%) of the 39,243 patients undergoing bioprosthetic mitral valve surgery were on a DOAC at discharge.

Among those receiving a mechanical value and placed on a DOAC, about two-thirds were on a factor Xa inhibitor rather than dabigatran. For those receiving a bioprosthetic value, the proportion was greater than 80%. Dr. Kalra speculated that the RE-ALIGN trial might be the reason factor Xa inhibitors were favored.

In both types of valves, whether mechanical or bioprosthetic, more comorbidities predicted a greater likelihood of receiving a DOAC rather than warfarin. For those receiving mechanical values, the comorbidities with a significant association with greater DOAC use included hypertension (P = .003), dyslipidemia (P = .02), arrhythmia (P < .001), and peripheral arterial disease (P < 0.001).

The same factors were significant for predicting increased likelihood of a DOAC following bioprosthetic valve replacement, but there were additional factors, including atrial fibrillation independent of other types of arrhythmias (P < .001), a factor not significant for mechanical valves, as well as diabetes (P < .001), cerebrovascular disease (P < .001), dialysis (P < .001), and endocarditis (P < .001).

“This is probably intuitive, but patients who were on a factor Xa inhibitor before their valve replacement were also more likely to be discharged on a factor Xa inhibitor,” Dr. Kalra said at the virtual meeting, sponsored by MedStar Heart & Vascular Institute.

The year-to-year increase in DOAC use among those undergoing bioprosthetic valve replacement over the study period, which was a significant trend, was not observed among those undergoing mechanical valve replacement. Rather, the 1% proportion remained stable over the study period.

“We wanted to look at outcomes, but we found that the STS database, which only includes data out to 30 days, is not structured for this type of analysis,” Dr. Kalra said. He was also concerned about the limitations of a comparison in which 1% of the sample was being compared to 99%.
 

Expert: One percent is ‘very small number’

David J. Cohen, MD, commented on the 1% figure, which was so low that a moderator questioned whether it could be due mostly to coding errors.

“This is a very, very small number so at some level it is reassuring that it is so low in the mechanical valves,” Dr. Cohen said. However, he was more circumspect about the larger number in bioprosthetic valves.

“I have always thought it was a bit strange there was a warning against using them in bioprosthetic valves, especially in the aortic position,” he said.

Direct oral anticoagulants (DOACs) are used in about 1% of patients undergoing surgical mechanical aortic and mitral valve replacement, but in up to 6% of surgical bioprosthetic valve replacements, according to registry data presented at CRT 2021.

In an analysis of the Society of Thoracic Surgery (STS) registry during 2014-2017, DOAC use increased steadily among those undergoing surgical bioprosthetic valve replacement, reaching a number that is potentially clinically significant, according to Ankur Kalra, MD, an interventional cardiologist at Akron General Hospital who has an academic appointment at the Cleveland Clinic.

There was no increase in the use of DOACs observed among patients undergoing mechanical valve replacement, “but even if the number is 1%, they should probably not be used at all until we accrue more data,” Dr. Kalra said.
 

DOACs discouraged in patients with mechanical or bioprosthetic valves

In Food and Drug Administration labeling, DOACs are contraindicated or not recommended. This can be traced to the randomized RE-ALIGN trial, which was stopped prematurely due to evidence of harm from a DOAC, according to Dr. Kalra.

In RE-ALIGN, which enrolled patients undergoing mechanical aortic or mitral valve replacement, dabigatran was associated not only with more bleeding events than warfarin, but also more thromboembolic events.

There are no randomized data comparing the factor Xa inhibitors rivaroxaban or apixaban to warfarin in heart valve surgery, but Dr. Kalra noted cautionary language is found in the labeling of both, “perhaps due to the RE-ALIGN data.”
 

Registry shows trends in prescribing

In the STS registry data, 193 (1.1%) of the 18,142 patients undergoing mechanical aortic valve surgery, 139 (1.0%) of the 13,942 patients undergoing mechanical mitral valve surgery, 5,625 (4.7%) of the 116,203 patients undergoing aortic bioprosthetic aortic valve surgery, and 2,180 (5.9%) of the 39,243 patients undergoing bioprosthetic mitral valve surgery were on a DOAC at discharge.

Among those receiving a mechanical value and placed on a DOAC, about two-thirds were on a factor Xa inhibitor rather than dabigatran. For those receiving a bioprosthetic value, the proportion was greater than 80%. Dr. Kalra speculated that the RE-ALIGN trial might be the reason factor Xa inhibitors were favored.

In both types of valves, whether mechanical or bioprosthetic, more comorbidities predicted a greater likelihood of receiving a DOAC rather than warfarin. For those receiving mechanical values, the comorbidities with a significant association with greater DOAC use included hypertension (P = .003), dyslipidemia (P = .02), arrhythmia (P < .001), and peripheral arterial disease (P < 0.001).

The same factors were significant for predicting increased likelihood of a DOAC following bioprosthetic valve replacement, but there were additional factors, including atrial fibrillation independent of other types of arrhythmias (P < .001), a factor not significant for mechanical valves, as well as diabetes (P < .001), cerebrovascular disease (P < .001), dialysis (P < .001), and endocarditis (P < .001).

“This is probably intuitive, but patients who were on a factor Xa inhibitor before their valve replacement were also more likely to be discharged on a factor Xa inhibitor,” Dr. Kalra said at the virtual meeting, sponsored by MedStar Heart & Vascular Institute.

The year-to-year increase in DOAC use among those undergoing bioprosthetic valve replacement over the study period, which was a significant trend, was not observed among those undergoing mechanical valve replacement. Rather, the 1% proportion remained stable over the study period.

“We wanted to look at outcomes, but we found that the STS database, which only includes data out to 30 days, is not structured for this type of analysis,” Dr. Kalra said. He was also concerned about the limitations of a comparison in which 1% of the sample was being compared to 99%.
 

Expert: One percent is ‘very small number’

David J. Cohen, MD, commented on the 1% figure, which was so low that a moderator questioned whether it could be due mostly to coding errors.

“This is a very, very small number so at some level it is reassuring that it is so low in the mechanical valves,” Dr. Cohen said. However, he was more circumspect about the larger number in bioprosthetic valves.

“I have always thought it was a bit strange there was a warning against using them in bioprosthetic valves, especially in the aortic position,” he said.

Direct oral anticoagulants (DOACs) are used in about 1% of patients undergoing surgical mechanical aortic and mitral valve replacement, but in up to 6% of surgical bioprosthetic valve replacements, according to registry data presented at CRT 2021.

In an analysis of the Society of Thoracic Surgery (STS) registry during 2014-2017, DOAC use increased steadily among those undergoing surgical bioprosthetic valve replacement, reaching a number that is potentially clinically significant, according to Ankur Kalra, MD, an interventional cardiologist at Akron General Hospital who has an academic appointment at the Cleveland Clinic.

There was no increase in the use of DOACs observed among patients undergoing mechanical valve replacement, “but even if the number is 1%, they should probably not be used at all until we accrue more data,” Dr. Kalra said.
 

DOACs discouraged in patients with mechanical or bioprosthetic valves

In Food and Drug Administration labeling, DOACs are contraindicated or not recommended. This can be traced to the randomized RE-ALIGN trial, which was stopped prematurely due to evidence of harm from a DOAC, according to Dr. Kalra.

In RE-ALIGN, which enrolled patients undergoing mechanical aortic or mitral valve replacement, dabigatran was associated not only with more bleeding events than warfarin, but also more thromboembolic events.

There are no randomized data comparing the factor Xa inhibitors rivaroxaban or apixaban to warfarin in heart valve surgery, but Dr. Kalra noted cautionary language is found in the labeling of both, “perhaps due to the RE-ALIGN data.”
 

Registry shows trends in prescribing

In the STS registry data, 193 (1.1%) of the 18,142 patients undergoing mechanical aortic valve surgery, 139 (1.0%) of the 13,942 patients undergoing mechanical mitral valve surgery, 5,625 (4.7%) of the 116,203 patients undergoing aortic bioprosthetic aortic valve surgery, and 2,180 (5.9%) of the 39,243 patients undergoing bioprosthetic mitral valve surgery were on a DOAC at discharge.

Among those receiving a mechanical value and placed on a DOAC, about two-thirds were on a factor Xa inhibitor rather than dabigatran. For those receiving a bioprosthetic value, the proportion was greater than 80%. Dr. Kalra speculated that the RE-ALIGN trial might be the reason factor Xa inhibitors were favored.

In both types of valves, whether mechanical or bioprosthetic, more comorbidities predicted a greater likelihood of receiving a DOAC rather than warfarin. For those receiving mechanical values, the comorbidities with a significant association with greater DOAC use included hypertension (P = .003), dyslipidemia (P = .02), arrhythmia (P < .001), and peripheral arterial disease (P < 0.001).

The same factors were significant for predicting increased likelihood of a DOAC following bioprosthetic valve replacement, but there were additional factors, including atrial fibrillation independent of other types of arrhythmias (P < .001), a factor not significant for mechanical valves, as well as diabetes (P < .001), cerebrovascular disease (P < .001), dialysis (P < .001), and endocarditis (P < .001).

“This is probably intuitive, but patients who were on a factor Xa inhibitor before their valve replacement were also more likely to be discharged on a factor Xa inhibitor,” Dr. Kalra said at the virtual meeting, sponsored by MedStar Heart & Vascular Institute.

The year-to-year increase in DOAC use among those undergoing bioprosthetic valve replacement over the study period, which was a significant trend, was not observed among those undergoing mechanical valve replacement. Rather, the 1% proportion remained stable over the study period.

“We wanted to look at outcomes, but we found that the STS database, which only includes data out to 30 days, is not structured for this type of analysis,” Dr. Kalra said. He was also concerned about the limitations of a comparison in which 1% of the sample was being compared to 99%.
 

Expert: One percent is ‘very small number’

David J. Cohen, MD, commented on the 1% figure, which was so low that a moderator questioned whether it could be due mostly to coding errors.

“This is a very, very small number so at some level it is reassuring that it is so low in the mechanical valves,” Dr. Cohen said. However, he was more circumspect about the larger number in bioprosthetic valves.

“I have always thought it was a bit strange there was a warning against using them in bioprosthetic valves, especially in the aortic position,” he said.

In patients with acute ischemic stroke, the use of thrombolysis in the late window of 4.5-9 hours after symptom onset was not associated with an increase in clot migration that would cause reduced clot accessibility to endovascular therapy, a new analysis from the EXTEND trial shows.

“There was no significant difference in the incidence of clot migration leading to clot inaccessibility in patients who received placebo or (intravenous) thrombolysis,” the authors report.

“Our results found no convincing evidence against the use of bridging thrombolysis before endovascular therapy in patients with acute ischemic stroke who present outside the 4.5-hour window,” they conclude.

“This information is important because it provides some comfort for neurointerventionists that IV thrombolysis does not unduly increase the risk of clot migration,” senior author, Bernard Yan, DMedSci, FRACP, told this news organization.

The study was published online in Stroke on Feb. 16.

The Australian researchers explain that endovascular thrombectomy is the standard of care in patients presenting with acute ischemic stroke caused by large-vessel occlusion, and current treatment guidelines recommend bridging thrombolysis for all patients receiving thrombectomy within the 4.5-hour time window.

While thrombectomy is also recommended in selected patients up to 24 hours after onset of symptoms, it remains unclear whether thrombolysis pretreatment should be administered in this setting.

One of the issues that might affect use of thrombolysis is distal clot migration. As proximal clot location is a crucial factor determining suitability for endovascular clot retrieval, distal migration may prevent successful thrombectomy, they note.   

“Clot migration can happen any time and makes life more difficult for the neurointerventionist who performs the endovascular clot retrieval,” added Dr. Yan, who is a neurologist and neurointerventionist at the Royal Melbourne Hospital, Australia.

In the current paper, the researchers report a retrospective analysis of data from the EXTEND trial of late thrombolysis, defined as 4.5-9 hours after symptom onset, to investigate the association between thrombolysis and clot migration leading to clot irretrievability.

The analysis included a total of 220 patients (109 patients in the placebo group and 111 in the thrombolysis group).

Results showed that retrievable clot was seen on baseline imaging in 69% of patients in the placebo group and 61% in the thrombolysis group. Clot resolution occurred in 28% of patients in the placebo group and 50% in the thrombolysis group. 

No significant difference was observed in the incidence of clot migration leading to inaccessibility between groups. Clot migration from a retrievable to nonretrievable location occurred in 19% of the placebo group and 14% of the thrombolysis group, with an odds ratio for clot migration in the thrombolysis group of 0.70 (95% confidence interval, 0.35-1.44). This outcome was consistent across subgroups.

The researchers note that, to their knowledge, this is the first randomized controlled study to assess the effect of thrombolysis on clot migration and accessibility in an extended time window.

They acknowledge that a limitation of this study is that they only assessed clot migration from a retrievable to a nonretrievable location; therefore, the true frequency of any clot migration occurring was likely to be higher, and this could explain why other reports have found higher odds ratios of clot migration.

But they point out that they chose to limit their analysis in this way specifically to guide decision-making regarding bridging thrombolysis incorporating endovascular therapy in the extended time window.

“The findings of this study are highly relevant in the current clinical environment, where there are multiple ongoing trials looking at removing thrombolysis pretreatment within the 4.5-hour time window in thrombectomy patients,” the authors write.  

“We have demonstrated that thrombolysis in the 4.5- to 9-hour window is not associated with reduced clot accessibility, and this information will be useful in future trial designs incorporating this extended time window,” they add.

Commenting on the study for this news organization, Michael Hill, MD, University of Calgary (Alta.), said: “Thrombus migration does happen and is likely part of the natural history of ischemic stroke, which may be influenced by therapeutics such as thrombolysis. This paper’s top-line result is that thrombus migration occurs in both treated and untreated groups – and therefore that this is really an observation of natural history.”

Dr. Hill says that, at present, patients should be treated with thrombolysis before endovascular therapy if they are eligible, and these results do not change that recommendation. 

“The results of the ongoing trials comparing direct thrombectomy with thrombolysis plus thrombectomy will help to understand the potential clinical outcome relevance of this phenomenon,” he added.

The EXTEND trial was supported by grants from the Australian National Health and Medical Research Council of Australia and the Commonwealth Scientific and Industrial Research Organization Flagship Program. Dr. Yan reported no relevant financial relationships.

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

In patients with acute ischemic stroke, the use of thrombolysis in the late window of 4.5-9 hours after symptom onset was not associated with an increase in clot migration that would cause reduced clot accessibility to endovascular therapy, a new analysis from the EXTEND trial shows.

“There was no significant difference in the incidence of clot migration leading to clot inaccessibility in patients who received placebo or (intravenous) thrombolysis,” the authors report.

“Our results found no convincing evidence against the use of bridging thrombolysis before endovascular therapy in patients with acute ischemic stroke who present outside the 4.5-hour window,” they conclude.

“This information is important because it provides some comfort for neurointerventionists that IV thrombolysis does not unduly increase the risk of clot migration,” senior author, Bernard Yan, DMedSci, FRACP, told this news organization.

The study was published online in Stroke on Feb. 16.

The Australian researchers explain that endovascular thrombectomy is the standard of care in patients presenting with acute ischemic stroke caused by large-vessel occlusion, and current treatment guidelines recommend bridging thrombolysis for all patients receiving thrombectomy within the 4.5-hour time window.

While thrombectomy is also recommended in selected patients up to 24 hours after onset of symptoms, it remains unclear whether thrombolysis pretreatment should be administered in this setting.

One of the issues that might affect use of thrombolysis is distal clot migration. As proximal clot location is a crucial factor determining suitability for endovascular clot retrieval, distal migration may prevent successful thrombectomy, they note.   

“Clot migration can happen any time and makes life more difficult for the neurointerventionist who performs the endovascular clot retrieval,” added Dr. Yan, who is a neurologist and neurointerventionist at the Royal Melbourne Hospital, Australia.

In the current paper, the researchers report a retrospective analysis of data from the EXTEND trial of late thrombolysis, defined as 4.5-9 hours after symptom onset, to investigate the association between thrombolysis and clot migration leading to clot irretrievability.

The analysis included a total of 220 patients (109 patients in the placebo group and 111 in the thrombolysis group).

Results showed that retrievable clot was seen on baseline imaging in 69% of patients in the placebo group and 61% in the thrombolysis group. Clot resolution occurred in 28% of patients in the placebo group and 50% in the thrombolysis group. 

No significant difference was observed in the incidence of clot migration leading to inaccessibility between groups. Clot migration from a retrievable to nonretrievable location occurred in 19% of the placebo group and 14% of the thrombolysis group, with an odds ratio for clot migration in the thrombolysis group of 0.70 (95% confidence interval, 0.35-1.44). This outcome was consistent across subgroups.

The researchers note that, to their knowledge, this is the first randomized controlled study to assess the effect of thrombolysis on clot migration and accessibility in an extended time window.

They acknowledge that a limitation of this study is that they only assessed clot migration from a retrievable to a nonretrievable location; therefore, the true frequency of any clot migration occurring was likely to be higher, and this could explain why other reports have found higher odds ratios of clot migration.

But they point out that they chose to limit their analysis in this way specifically to guide decision-making regarding bridging thrombolysis incorporating endovascular therapy in the extended time window.

“The findings of this study are highly relevant in the current clinical environment, where there are multiple ongoing trials looking at removing thrombolysis pretreatment within the 4.5-hour time window in thrombectomy patients,” the authors write.  

“We have demonstrated that thrombolysis in the 4.5- to 9-hour window is not associated with reduced clot accessibility, and this information will be useful in future trial designs incorporating this extended time window,” they add.

Commenting on the study for this news organization, Michael Hill, MD, University of Calgary (Alta.), said: “Thrombus migration does happen and is likely part of the natural history of ischemic stroke, which may be influenced by therapeutics such as thrombolysis. This paper’s top-line result is that thrombus migration occurs in both treated and untreated groups – and therefore that this is really an observation of natural history.”

Dr. Hill says that, at present, patients should be treated with thrombolysis before endovascular therapy if they are eligible, and these results do not change that recommendation. 

“The results of the ongoing trials comparing direct thrombectomy with thrombolysis plus thrombectomy will help to understand the potential clinical outcome relevance of this phenomenon,” he added.

The EXTEND trial was supported by grants from the Australian National Health and Medical Research Council of Australia and the Commonwealth Scientific and Industrial Research Organization Flagship Program. Dr. Yan reported no relevant financial relationships.

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

In patients with acute ischemic stroke, the use of thrombolysis in the late window of 4.5-9 hours after symptom onset was not associated with an increase in clot migration that would cause reduced clot accessibility to endovascular therapy, a new analysis from the EXTEND trial shows.

“There was no significant difference in the incidence of clot migration leading to clot inaccessibility in patients who received placebo or (intravenous) thrombolysis,” the authors report.

“Our results found no convincing evidence against the use of bridging thrombolysis before endovascular therapy in patients with acute ischemic stroke who present outside the 4.5-hour window,” they conclude.

“This information is important because it provides some comfort for neurointerventionists that IV thrombolysis does not unduly increase the risk of clot migration,” senior author, Bernard Yan, DMedSci, FRACP, told this news organization.

The study was published online in Stroke on Feb. 16.

The Australian researchers explain that endovascular thrombectomy is the standard of care in patients presenting with acute ischemic stroke caused by large-vessel occlusion, and current treatment guidelines recommend bridging thrombolysis for all patients receiving thrombectomy within the 4.5-hour time window.

While thrombectomy is also recommended in selected patients up to 24 hours after onset of symptoms, it remains unclear whether thrombolysis pretreatment should be administered in this setting.

One of the issues that might affect use of thrombolysis is distal clot migration. As proximal clot location is a crucial factor determining suitability for endovascular clot retrieval, distal migration may prevent successful thrombectomy, they note.   

“Clot migration can happen any time and makes life more difficult for the neurointerventionist who performs the endovascular clot retrieval,” added Dr. Yan, who is a neurologist and neurointerventionist at the Royal Melbourne Hospital, Australia.

In the current paper, the researchers report a retrospective analysis of data from the EXTEND trial of late thrombolysis, defined as 4.5-9 hours after symptom onset, to investigate the association between thrombolysis and clot migration leading to clot irretrievability.

The analysis included a total of 220 patients (109 patients in the placebo group and 111 in the thrombolysis group).

Results showed that retrievable clot was seen on baseline imaging in 69% of patients in the placebo group and 61% in the thrombolysis group. Clot resolution occurred in 28% of patients in the placebo group and 50% in the thrombolysis group. 

No significant difference was observed in the incidence of clot migration leading to inaccessibility between groups. Clot migration from a retrievable to nonretrievable location occurred in 19% of the placebo group and 14% of the thrombolysis group, with an odds ratio for clot migration in the thrombolysis group of 0.70 (95% confidence interval, 0.35-1.44). This outcome was consistent across subgroups.

The researchers note that, to their knowledge, this is the first randomized controlled study to assess the effect of thrombolysis on clot migration and accessibility in an extended time window.

They acknowledge that a limitation of this study is that they only assessed clot migration from a retrievable to a nonretrievable location; therefore, the true frequency of any clot migration occurring was likely to be higher, and this could explain why other reports have found higher odds ratios of clot migration.

But they point out that they chose to limit their analysis in this way specifically to guide decision-making regarding bridging thrombolysis incorporating endovascular therapy in the extended time window.

“The findings of this study are highly relevant in the current clinical environment, where there are multiple ongoing trials looking at removing thrombolysis pretreatment within the 4.5-hour time window in thrombectomy patients,” the authors write.  

“We have demonstrated that thrombolysis in the 4.5- to 9-hour window is not associated with reduced clot accessibility, and this information will be useful in future trial designs incorporating this extended time window,” they add.

Commenting on the study for this news organization, Michael Hill, MD, University of Calgary (Alta.), said: “Thrombus migration does happen and is likely part of the natural history of ischemic stroke, which may be influenced by therapeutics such as thrombolysis. This paper’s top-line result is that thrombus migration occurs in both treated and untreated groups – and therefore that this is really an observation of natural history.”

Dr. Hill says that, at present, patients should be treated with thrombolysis before endovascular therapy if they are eligible, and these results do not change that recommendation. 

“The results of the ongoing trials comparing direct thrombectomy with thrombolysis plus thrombectomy will help to understand the potential clinical outcome relevance of this phenomenon,” he added.

The EXTEND trial was supported by grants from the Australian National Health and Medical Research Council of Australia and the Commonwealth Scientific and Industrial Research Organization Flagship Program. Dr. Yan reported no relevant financial relationships.

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

New guidelines from the American Society of Hematology “strongly recommend” using no thromboprophylaxis over using parenteral thromboprophylaxis in ambulatory patients receiving cancer chemotherapy who have low venous thromboembolism (VTE) risk, and using no thromboprophylaxis over oral thromboprophylaxis with vitamin K antagonists in those at any VTE risk level.

The evidence-based guidelines for the prevention and treatment of VTE in patient with cancer, published online in Blood Advances, also include a “conditional recommendation” for using either thromboprophylaxis with the direct oral anticoagulants (DOACs) apixaban or rivaroxaban or using no thromboprophylaxis in ambulatory patients with intermediate risk and using the DOACs over no thromboprophylaxis in those with high VTE risk.

The purpose of the guidelines, which also address VTE prophylaxis in hospitalized patients with cancer and the use of anticoagulation for VTE treatment in patients with cancer, is to provide clinical decision support for shared decision-making by patients and clinicians, Gary H. Lyman, MD, of Fred Hutchinson Cancer Research Center, Seattle and Marc Carrier, MD, of the University of Ottawa, and their colleagues from the multidisciplinary guidelines panel explained.

“The recommendations take into consideration the strength of the evidence, risks of mortality, VTE, and bleeding, as well as quality of life, acceptability, and cost considerations,” they wrote, noting that VTE is a common complication in patients with cancer, who are at markedly increased risk for morbidity and mortality from VTE.
 

Levels of evidence

The panel members relied on updated and original systematic evidence reviews. Conditional recommendations, as opposed to strong recommendations, are defined by the panel as “suggestions,” and all 33 recommendations that make up the guidelines include a statement on the strength of the relevant evidence.

For example, the thromboprophylaxis recommendations for low, intermediate, and high VTE risk are made based on “moderate certainty in the evidence of effects,” and the recommendation for no thromboprophylaxis over oral thromboprophylaxis with vitamin K antagonists is a strong recommendation based on “very low certainty in the evidence of benefits, but high certainty about the harms.”

The guidelines panel also strongly recommends, based on moderate certainty in the evidence of effects, using low-molecular-weight heparin over unfractionated heparin for the initial treatment of VTE in patients with cancer, and suggests, based on “very low certainty in the evidence of effects,” using LMWH over fondaparinux in this setting.

In addition to primary prophylaxis in ambulatory and hospitalized patients and initial VTE treatment, they also address primary prophylaxis for patients with cancer who have a central venous catheter, VTE treatment in surgical patients with cancer, short-term VTE treatment, and long-term VTE treatment.

For example, the guidelines panel conditionally recommends:

• Not using parenteral or oral thromboprophylaxis in patients with cancer and a central venous catheter
• Using LMWH or fondaparinux for surgical patients with cancer
• Using DOACS for the short-term treatment of VTE, and LMWH or DOACs for the long-term treatment of VTE in patients with cancer.

The perils of VTE

VTE in patients with cancer can interfere with treatment, increase mortality risk, and increase costs, the authors noted, adding that VTE can also adversely affect cancer patients’ quality of life.

“Some have even reported the experience of VTE to be more upsetting than that of the cancer,” they wrote. “More than 50% of thrombotic events occur within 3 months of the cancer diagnosis, a time when most cancer treatments will be underway. Patients, who are still coming to terms with a recent cancer diagnosis, often view the occurrence of VTE as a further threat to life, confirmation of the severity of their condition, and a poor prognostic sign.”

Therefore, the new guidelines aim to reduce VTE frequency, risk of bleeding complications, morbidity, and costs, thereby improving quality of life and the patient experience, the authors said, noting that three other recent guidelines on VTEs in patients with cancer have been published: the 2019 American Society of Clinical Oncology guidelines, the 2019 International Initiative on Thrombosis and Cancer guidelines, and the 2020 National Comprehensive Cancer Network guidelines.

The ASH guidelines are similar in many ways to the other guidelines, but differ in some ways, as well. An example is the timing of initiation of pharmacological thromboprophylaxis in patients undergoing cancer-related major abdominal surgery. The ASCO and ITAC guidelines advise starting thromboprophylaxis preoperatively, whereas the ASH guidelines recommend initiating thromboprophylaxis postoperatively, citing “the limited advantages to initiating thromboprophylaxis preoperatively, in addition to the potential bleeding and logistical considerations associated with neuraxial anesthesia.”

These differences highlight a lack of data in that setting and the need for additional studies, the authors said.
 

ASH vs. ASCO

James Douketis, MD, a practicing clinician and professor of medicine at McMaster University, Hamilton, Ont., highlighted another difference between the ASH and ASCO guidelines.

“For the treatment of [cancer-associated thrombosis], ASCO gives a strong recommendation to use LMWH or DOACs (with some caveats), which is easy to follow. ASH, on the other hand, suggests LMWH or a DOAC for the first 7-10 days, DOACs for the first 3-6 months, and back to LMWH or DOACs after 6 months,” he said in an interview.

The recommendation is “very evidence based but ambiguous and not helpful for the practicing clinician,” added Dr. Douketis, who helped develop the ITAC guidelines, but was not part of the ASH or ASCO guideline panels.

ASCO also provides a clear recommendation for giving VTE prophylaxis for 4 weeks after cancer surgery in patients with high VTE risk, whereas ASH gives “a somewhat vague recommendation” for thromboprophylaxis after hospital discharge.

The guidelines are “pretty well aligned” with respect to recommendations on VTE prophylaxis in medical cancer patients receiving chemotherapy, and although the “extremely academic” ASH guidelines were developed by “a superb team using the same evidence and excellent methodology,” they are interpreted in slightly different ways and fall short when it comes to being clinician friendly, Dr. Douketis said.

“At the end of day, for practicing clinicians, the ASH guidelines don’t provide a message that’s easy to digest,” he added.

ASH has, however, provided a resource page that includes tools and information for implementing the guidelines in clinical practice, and will maintain the guidelines “through surveillance for new evidence, ongoing review by experts, and regular revisions,” the authors said.

[email protected]

New guidelines from the American Society of Hematology “strongly recommend” using no thromboprophylaxis over using parenteral thromboprophylaxis in ambulatory patients receiving cancer chemotherapy who have low venous thromboembolism (VTE) risk, and using no thromboprophylaxis over oral thromboprophylaxis with vitamin K antagonists in those at any VTE risk level.

The evidence-based guidelines for the prevention and treatment of VTE in patient with cancer, published online in Blood Advances, also include a “conditional recommendation” for using either thromboprophylaxis with the direct oral anticoagulants (DOACs) apixaban or rivaroxaban or using no thromboprophylaxis in ambulatory patients with intermediate risk and using the DOACs over no thromboprophylaxis in those with high VTE risk.

The purpose of the guidelines, which also address VTE prophylaxis in hospitalized patients with cancer and the use of anticoagulation for VTE treatment in patients with cancer, is to provide clinical decision support for shared decision-making by patients and clinicians, Gary H. Lyman, MD, of Fred Hutchinson Cancer Research Center, Seattle and Marc Carrier, MD, of the University of Ottawa, and their colleagues from the multidisciplinary guidelines panel explained.

“The recommendations take into consideration the strength of the evidence, risks of mortality, VTE, and bleeding, as well as quality of life, acceptability, and cost considerations,” they wrote, noting that VTE is a common complication in patients with cancer, who are at markedly increased risk for morbidity and mortality from VTE.
 

Levels of evidence

The panel members relied on updated and original systematic evidence reviews. Conditional recommendations, as opposed to strong recommendations, are defined by the panel as “suggestions,” and all 33 recommendations that make up the guidelines include a statement on the strength of the relevant evidence.

For example, the thromboprophylaxis recommendations for low, intermediate, and high VTE risk are made based on “moderate certainty in the evidence of effects,” and the recommendation for no thromboprophylaxis over oral thromboprophylaxis with vitamin K antagonists is a strong recommendation based on “very low certainty in the evidence of benefits, but high certainty about the harms.”

The guidelines panel also strongly recommends, based on moderate certainty in the evidence of effects, using low-molecular-weight heparin over unfractionated heparin for the initial treatment of VTE in patients with cancer, and suggests, based on “very low certainty in the evidence of effects,” using LMWH over fondaparinux in this setting.

In addition to primary prophylaxis in ambulatory and hospitalized patients and initial VTE treatment, they also address primary prophylaxis for patients with cancer who have a central venous catheter, VTE treatment in surgical patients with cancer, short-term VTE treatment, and long-term VTE treatment.

For example, the guidelines panel conditionally recommends:

• Not using parenteral or oral thromboprophylaxis in patients with cancer and a central venous catheter
• Using LMWH or fondaparinux for surgical patients with cancer
• Using DOACS for the short-term treatment of VTE, and LMWH or DOACs for the long-term treatment of VTE in patients with cancer.

The perils of VTE

VTE in patients with cancer can interfere with treatment, increase mortality risk, and increase costs, the authors noted, adding that VTE can also adversely affect cancer patients’ quality of life.

“Some have even reported the experience of VTE to be more upsetting than that of the cancer,” they wrote. “More than 50% of thrombotic events occur within 3 months of the cancer diagnosis, a time when most cancer treatments will be underway. Patients, who are still coming to terms with a recent cancer diagnosis, often view the occurrence of VTE as a further threat to life, confirmation of the severity of their condition, and a poor prognostic sign.”

Therefore, the new guidelines aim to reduce VTE frequency, risk of bleeding complications, morbidity, and costs, thereby improving quality of life and the patient experience, the authors said, noting that three other recent guidelines on VTEs in patients with cancer have been published: the 2019 American Society of Clinical Oncology guidelines, the 2019 International Initiative on Thrombosis and Cancer guidelines, and the 2020 National Comprehensive Cancer Network guidelines.

The ASH guidelines are similar in many ways to the other guidelines, but differ in some ways, as well. An example is the timing of initiation of pharmacological thromboprophylaxis in patients undergoing cancer-related major abdominal surgery. The ASCO and ITAC guidelines advise starting thromboprophylaxis preoperatively, whereas the ASH guidelines recommend initiating thromboprophylaxis postoperatively, citing “the limited advantages to initiating thromboprophylaxis preoperatively, in addition to the potential bleeding and logistical considerations associated with neuraxial anesthesia.”

These differences highlight a lack of data in that setting and the need for additional studies, the authors said.
 

ASH vs. ASCO

James Douketis, MD, a practicing clinician and professor of medicine at McMaster University, Hamilton, Ont., highlighted another difference between the ASH and ASCO guidelines.

“For the treatment of [cancer-associated thrombosis], ASCO gives a strong recommendation to use LMWH or DOACs (with some caveats), which is easy to follow. ASH, on the other hand, suggests LMWH or a DOAC for the first 7-10 days, DOACs for the first 3-6 months, and back to LMWH or DOACs after 6 months,” he said in an interview.

The recommendation is “very evidence based but ambiguous and not helpful for the practicing clinician,” added Dr. Douketis, who helped develop the ITAC guidelines, but was not part of the ASH or ASCO guideline panels.

ASCO also provides a clear recommendation for giving VTE prophylaxis for 4 weeks after cancer surgery in patients with high VTE risk, whereas ASH gives “a somewhat vague recommendation” for thromboprophylaxis after hospital discharge.

The guidelines are “pretty well aligned” with respect to recommendations on VTE prophylaxis in medical cancer patients receiving chemotherapy, and although the “extremely academic” ASH guidelines were developed by “a superb team using the same evidence and excellent methodology,” they are interpreted in slightly different ways and fall short when it comes to being clinician friendly, Dr. Douketis said.

“At the end of day, for practicing clinicians, the ASH guidelines don’t provide a message that’s easy to digest,” he added.

ASH has, however, provided a resource page that includes tools and information for implementing the guidelines in clinical practice, and will maintain the guidelines “through surveillance for new evidence, ongoing review by experts, and regular revisions,” the authors said.

[email protected]

New guidelines from the American Society of Hematology “strongly recommend” using no thromboprophylaxis over using parenteral thromboprophylaxis in ambulatory patients receiving cancer chemotherapy who have low venous thromboembolism (VTE) risk, and using no thromboprophylaxis over oral thromboprophylaxis with vitamin K antagonists in those at any VTE risk level.

The evidence-based guidelines for the prevention and treatment of VTE in patient with cancer, published online in Blood Advances, also include a “conditional recommendation” for using either thromboprophylaxis with the direct oral anticoagulants (DOACs) apixaban or rivaroxaban or using no thromboprophylaxis in ambulatory patients with intermediate risk and using the DOACs over no thromboprophylaxis in those with high VTE risk.

The purpose of the guidelines, which also address VTE prophylaxis in hospitalized patients with cancer and the use of anticoagulation for VTE treatment in patients with cancer, is to provide clinical decision support for shared decision-making by patients and clinicians, Gary H. Lyman, MD, of Fred Hutchinson Cancer Research Center, Seattle and Marc Carrier, MD, of the University of Ottawa, and their colleagues from the multidisciplinary guidelines panel explained.

“The recommendations take into consideration the strength of the evidence, risks of mortality, VTE, and bleeding, as well as quality of life, acceptability, and cost considerations,” they wrote, noting that VTE is a common complication in patients with cancer, who are at markedly increased risk for morbidity and mortality from VTE.
 

Levels of evidence

The panel members relied on updated and original systematic evidence reviews. Conditional recommendations, as opposed to strong recommendations, are defined by the panel as “suggestions,” and all 33 recommendations that make up the guidelines include a statement on the strength of the relevant evidence.

For example, the thromboprophylaxis recommendations for low, intermediate, and high VTE risk are made based on “moderate certainty in the evidence of effects,” and the recommendation for no thromboprophylaxis over oral thromboprophylaxis with vitamin K antagonists is a strong recommendation based on “very low certainty in the evidence of benefits, but high certainty about the harms.”

The guidelines panel also strongly recommends, based on moderate certainty in the evidence of effects, using low-molecular-weight heparin over unfractionated heparin for the initial treatment of VTE in patients with cancer, and suggests, based on “very low certainty in the evidence of effects,” using LMWH over fondaparinux in this setting.

In addition to primary prophylaxis in ambulatory and hospitalized patients and initial VTE treatment, they also address primary prophylaxis for patients with cancer who have a central venous catheter, VTE treatment in surgical patients with cancer, short-term VTE treatment, and long-term VTE treatment.

For example, the guidelines panel conditionally recommends:

• Not using parenteral or oral thromboprophylaxis in patients with cancer and a central venous catheter
• Using LMWH or fondaparinux for surgical patients with cancer
• Using DOACS for the short-term treatment of VTE, and LMWH or DOACs for the long-term treatment of VTE in patients with cancer.

The perils of VTE

VTE in patients with cancer can interfere with treatment, increase mortality risk, and increase costs, the authors noted, adding that VTE can also adversely affect cancer patients’ quality of life.

“Some have even reported the experience of VTE to be more upsetting than that of the cancer,” they wrote. “More than 50% of thrombotic events occur within 3 months of the cancer diagnosis, a time when most cancer treatments will be underway. Patients, who are still coming to terms with a recent cancer diagnosis, often view the occurrence of VTE as a further threat to life, confirmation of the severity of their condition, and a poor prognostic sign.”

Therefore, the new guidelines aim to reduce VTE frequency, risk of bleeding complications, morbidity, and costs, thereby improving quality of life and the patient experience, the authors said, noting that three other recent guidelines on VTEs in patients with cancer have been published: the 2019 American Society of Clinical Oncology guidelines, the 2019 International Initiative on Thrombosis and Cancer guidelines, and the 2020 National Comprehensive Cancer Network guidelines.

The ASH guidelines are similar in many ways to the other guidelines, but differ in some ways, as well. An example is the timing of initiation of pharmacological thromboprophylaxis in patients undergoing cancer-related major abdominal surgery. The ASCO and ITAC guidelines advise starting thromboprophylaxis preoperatively, whereas the ASH guidelines recommend initiating thromboprophylaxis postoperatively, citing “the limited advantages to initiating thromboprophylaxis preoperatively, in addition to the potential bleeding and logistical considerations associated with neuraxial anesthesia.”

These differences highlight a lack of data in that setting and the need for additional studies, the authors said.
 

ASH vs. ASCO

James Douketis, MD, a practicing clinician and professor of medicine at McMaster University, Hamilton, Ont., highlighted another difference between the ASH and ASCO guidelines.

“For the treatment of [cancer-associated thrombosis], ASCO gives a strong recommendation to use LMWH or DOACs (with some caveats), which is easy to follow. ASH, on the other hand, suggests LMWH or a DOAC for the first 7-10 days, DOACs for the first 3-6 months, and back to LMWH or DOACs after 6 months,” he said in an interview.

The recommendation is “very evidence based but ambiguous and not helpful for the practicing clinician,” added Dr. Douketis, who helped develop the ITAC guidelines, but was not part of the ASH or ASCO guideline panels.

ASCO also provides a clear recommendation for giving VTE prophylaxis for 4 weeks after cancer surgery in patients with high VTE risk, whereas ASH gives “a somewhat vague recommendation” for thromboprophylaxis after hospital discharge.

The guidelines are “pretty well aligned” with respect to recommendations on VTE prophylaxis in medical cancer patients receiving chemotherapy, and although the “extremely academic” ASH guidelines were developed by “a superb team using the same evidence and excellent methodology,” they are interpreted in slightly different ways and fall short when it comes to being clinician friendly, Dr. Douketis said.

“At the end of day, for practicing clinicians, the ASH guidelines don’t provide a message that’s easy to digest,” he added.

ASH has, however, provided a resource page that includes tools and information for implementing the guidelines in clinical practice, and will maintain the guidelines “through surveillance for new evidence, ongoing review by experts, and regular revisions,” the authors said.

[email protected]

Over 10% of transgender men (females transitioning to male) who take testosterone develop high hematocrit levels that could put them at greater risk for a thrombotic event, and the largest increase in levels occurs in the first year after starting therapy, a new Dutch study indicates.

Erythrocytosis, defined as a hematocrit greater than 0.50 L/L, is a potentially serious side effect of testosterone therapy, say Milou Cecilia Madsen, MD, and colleagues in their article published online Feb. 18, 2021, in the Journal of Clinical Endocrinology & Metabolism.

When hematocrit was measured twice, 11.1% of the cohort of 1073 trans men had levels in excess of 0.50 L/L over a 20-year follow-up.

“Erythrocytosis is common in transgender men treated with testosterone, especially in those who smoke, have [a] high BMI [body mass index], and [who] use testosterone injections,” Dr. Madsen, of the VU University Medical Center Amsterdam, said in a statement from the Endocrine Society.

“A reasonable first step in the care of transgender men with high red blood cells while on testosterone is to advise them to quit smoking, switch injectable testosterone to gel, and, if BMI is high, to lose weight,” she added.
 

First large study of testosterone in trans men with 20-year follow-up

Transgender men often undergo testosterone therapy as part of gender-affirming treatment. 

Secondary erythrocytosis, a condition where the body makes too many red blood cells, is a common side effect of testosterone therapy that can increase the risk of thrombolic events, heart attack, and stroke, Dr. Madsen and colleagues explained.

This is the first study of a large cohort of trans men taking testosterone therapy followed for up to 20 years. Because of the large sample size, statistical analysis with many determinants could be performed. And because of the long follow-up, a clear time relation between initiation of testosterone therapy and hematocrit could be studied, they noted.

Participants were part of the Amsterdam Cohort of Gender Dysphoria study, a large cohort of individuals seen at the Center of Expertise on Gender Dysphoria at Amsterdam University Medical Center between 1972 and 2015.

Laboratory measurements taken between 2004 and 2018 were available for analysis. Trans men visited the center every 3-6 months during their first year of testosterone therapy and were then monitored every year or every other year.

Long-acting undecanoate injection was associated with the highest risk of a hematocrit level greater than 0.50 L/L, and the risk of erythrocytosis in those who took long-acting intramuscular injections was about threefold higher, compared with testosterone gel (adjusted odds ratio, 3.1).

In contrast, short-acting ester injections and oral administration of testosterone had a similar risk for erythrocytosis, as did testosterone gel.

Other determinants of elevated hematocrit included smoking, medical history of a number of comorbid conditions, and older age on initiation of testosterone.

In contrast, “higher testosterone levels per se were not associated with an increased odds of hematocrit greater than 0.50 L/L”, the authors noted.
 

Current advice for trans men based on old guidance for hypogonadism

The authors said that current advice for trans men is based on recommendations for testosterone-treated hypogonadal cis men (those assigned male at birth) from 2008, which advises a hematocrit greater than 0.50 L/L has a moderate to high risk of adverse outcome. For levels greater than 0.54 L/L, cessation of testosterone therapy, a dose reduction, or therapeutic phlebotomy to reduce the risk of adverse events is advised. For levels 0.50-0.54 L/L, no clear advice is given.

But questions remain as to whether these guidelines are applicable to trans men because the duration of testosterone therapy is much longer in trans men and hormone treatment often cannot be discontinued without causing distress.

Meanwhile, hematology guidelines indicate an upper limit for hematocrit for cis females of 0.48 L/L.

“It could be argued that the upper limit for cis females should be applied, as trans men are born with female genetics,” the authors said. “This is a subject for further research.”
 

Duration of testosterone therapy impacts risk of erythrocytosis

In the study, the researchers found that longer duration of testosterone therapy increased the risk of developing hematocrit levels greater than 0.50 L/L. For example, after 1 year, the cumulative incidence of erythrocytosis was 8%; after 10 years, it was 38%; and after 14 years, it was 50%.

Until more specific guidance is developed for trans men, if hematocrit levels rise to 0.50-0.54 L/L, the researchers suggested taking “reasonable” steps to prevent a further increase:

• Consider switching patients who use injectable testosterone to transdermal products.
• Advise patients with a BMI greater than 25 kg/m2 to lose weight to attain a BMI of 18.5-25.
• Advise patients to stop smoking.
• Pursue treatment optimization for chronic lung disease or sleep apnea.

The study had no external funding. The authors reported no relevant financial relationships.

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

Over 10% of transgender men (females transitioning to male) who take testosterone develop high hematocrit levels that could put them at greater risk for a thrombotic event, and the largest increase in levels occurs in the first year after starting therapy, a new Dutch study indicates.

Erythrocytosis, defined as a hematocrit greater than 0.50 L/L, is a potentially serious side effect of testosterone therapy, say Milou Cecilia Madsen, MD, and colleagues in their article published online Feb. 18, 2021, in the Journal of Clinical Endocrinology & Metabolism.

When hematocrit was measured twice, 11.1% of the cohort of 1073 trans men had levels in excess of 0.50 L/L over a 20-year follow-up.

“Erythrocytosis is common in transgender men treated with testosterone, especially in those who smoke, have [a] high BMI [body mass index], and [who] use testosterone injections,” Dr. Madsen, of the VU University Medical Center Amsterdam, said in a statement from the Endocrine Society.

“A reasonable first step in the care of transgender men with high red blood cells while on testosterone is to advise them to quit smoking, switch injectable testosterone to gel, and, if BMI is high, to lose weight,” she added.
 

First large study of testosterone in trans men with 20-year follow-up

Transgender men often undergo testosterone therapy as part of gender-affirming treatment. 

Secondary erythrocytosis, a condition where the body makes too many red blood cells, is a common side effect of testosterone therapy that can increase the risk of thrombolic events, heart attack, and stroke, Dr. Madsen and colleagues explained.

This is the first study of a large cohort of trans men taking testosterone therapy followed for up to 20 years. Because of the large sample size, statistical analysis with many determinants could be performed. And because of the long follow-up, a clear time relation between initiation of testosterone therapy and hematocrit could be studied, they noted.

Participants were part of the Amsterdam Cohort of Gender Dysphoria study, a large cohort of individuals seen at the Center of Expertise on Gender Dysphoria at Amsterdam University Medical Center between 1972 and 2015.

Laboratory measurements taken between 2004 and 2018 were available for analysis. Trans men visited the center every 3-6 months during their first year of testosterone therapy and were then monitored every year or every other year.

Long-acting undecanoate injection was associated with the highest risk of a hematocrit level greater than 0.50 L/L, and the risk of erythrocytosis in those who took long-acting intramuscular injections was about threefold higher, compared with testosterone gel (adjusted odds ratio, 3.1).

In contrast, short-acting ester injections and oral administration of testosterone had a similar risk for erythrocytosis, as did testosterone gel.

Other determinants of elevated hematocrit included smoking, medical history of a number of comorbid conditions, and older age on initiation of testosterone.

In contrast, “higher testosterone levels per se were not associated with an increased odds of hematocrit greater than 0.50 L/L”, the authors noted.
 

Current advice for trans men based on old guidance for hypogonadism

The authors said that current advice for trans men is based on recommendations for testosterone-treated hypogonadal cis men (those assigned male at birth) from 2008, which advises a hematocrit greater than 0.50 L/L has a moderate to high risk of adverse outcome. For levels greater than 0.54 L/L, cessation of testosterone therapy, a dose reduction, or therapeutic phlebotomy to reduce the risk of adverse events is advised. For levels 0.50-0.54 L/L, no clear advice is given.

But questions remain as to whether these guidelines are applicable to trans men because the duration of testosterone therapy is much longer in trans men and hormone treatment often cannot be discontinued without causing distress.

Meanwhile, hematology guidelines indicate an upper limit for hematocrit for cis females of 0.48 L/L.

“It could be argued that the upper limit for cis females should be applied, as trans men are born with female genetics,” the authors said. “This is a subject for further research.”
 

Duration of testosterone therapy impacts risk of erythrocytosis

In the study, the researchers found that longer duration of testosterone therapy increased the risk of developing hematocrit levels greater than 0.50 L/L. For example, after 1 year, the cumulative incidence of erythrocytosis was 8%; after 10 years, it was 38%; and after 14 years, it was 50%.

Until more specific guidance is developed for trans men, if hematocrit levels rise to 0.50-0.54 L/L, the researchers suggested taking “reasonable” steps to prevent a further increase:

• Consider switching patients who use injectable testosterone to transdermal products.
• Advise patients with a BMI greater than 25 kg/m2 to lose weight to attain a BMI of 18.5-25.
• Advise patients to stop smoking.
• Pursue treatment optimization for chronic lung disease or sleep apnea.

The study had no external funding. The authors reported no relevant financial relationships.

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

Over 10% of transgender men (females transitioning to male) who take testosterone develop high hematocrit levels that could put them at greater risk for a thrombotic event, and the largest increase in levels occurs in the first year after starting therapy, a new Dutch study indicates.

Erythrocytosis, defined as a hematocrit greater than 0.50 L/L, is a potentially serious side effect of testosterone therapy, say Milou Cecilia Madsen, MD, and colleagues in their article published online Feb. 18, 2021, in the Journal of Clinical Endocrinology & Metabolism.

When hematocrit was measured twice, 11.1% of the cohort of 1073 trans men had levels in excess of 0.50 L/L over a 20-year follow-up.

“Erythrocytosis is common in transgender men treated with testosterone, especially in those who smoke, have [a] high BMI [body mass index], and [who] use testosterone injections,” Dr. Madsen, of the VU University Medical Center Amsterdam, said in a statement from the Endocrine Society.

“A reasonable first step in the care of transgender men with high red blood cells while on testosterone is to advise them to quit smoking, switch injectable testosterone to gel, and, if BMI is high, to lose weight,” she added.
 

First large study of testosterone in trans men with 20-year follow-up

Transgender men often undergo testosterone therapy as part of gender-affirming treatment. 

Secondary erythrocytosis, a condition where the body makes too many red blood cells, is a common side effect of testosterone therapy that can increase the risk of thrombolic events, heart attack, and stroke, Dr. Madsen and colleagues explained.

This is the first study of a large cohort of trans men taking testosterone therapy followed for up to 20 years. Because of the large sample size, statistical analysis with many determinants could be performed. And because of the long follow-up, a clear time relation between initiation of testosterone therapy and hematocrit could be studied, they noted.

Participants were part of the Amsterdam Cohort of Gender Dysphoria study, a large cohort of individuals seen at the Center of Expertise on Gender Dysphoria at Amsterdam University Medical Center between 1972 and 2015.

Laboratory measurements taken between 2004 and 2018 were available for analysis. Trans men visited the center every 3-6 months during their first year of testosterone therapy and were then monitored every year or every other year.

Long-acting undecanoate injection was associated with the highest risk of a hematocrit level greater than 0.50 L/L, and the risk of erythrocytosis in those who took long-acting intramuscular injections was about threefold higher, compared with testosterone gel (adjusted odds ratio, 3.1).

In contrast, short-acting ester injections and oral administration of testosterone had a similar risk for erythrocytosis, as did testosterone gel.

Other determinants of elevated hematocrit included smoking, medical history of a number of comorbid conditions, and older age on initiation of testosterone.

In contrast, “higher testosterone levels per se were not associated with an increased odds of hematocrit greater than 0.50 L/L”, the authors noted.
 

Current advice for trans men based on old guidance for hypogonadism

The authors said that current advice for trans men is based on recommendations for testosterone-treated hypogonadal cis men (those assigned male at birth) from 2008, which advises a hematocrit greater than 0.50 L/L has a moderate to high risk of adverse outcome. For levels greater than 0.54 L/L, cessation of testosterone therapy, a dose reduction, or therapeutic phlebotomy to reduce the risk of adverse events is advised. For levels 0.50-0.54 L/L, no clear advice is given.

But questions remain as to whether these guidelines are applicable to trans men because the duration of testosterone therapy is much longer in trans men and hormone treatment often cannot be discontinued without causing distress.

Meanwhile, hematology guidelines indicate an upper limit for hematocrit for cis females of 0.48 L/L.

“It could be argued that the upper limit for cis females should be applied, as trans men are born with female genetics,” the authors said. “This is a subject for further research.”
 

Duration of testosterone therapy impacts risk of erythrocytosis

In the study, the researchers found that longer duration of testosterone therapy increased the risk of developing hematocrit levels greater than 0.50 L/L. For example, after 1 year, the cumulative incidence of erythrocytosis was 8%; after 10 years, it was 38%; and after 14 years, it was 50%.

Until more specific guidance is developed for trans men, if hematocrit levels rise to 0.50-0.54 L/L, the researchers suggested taking “reasonable” steps to prevent a further increase:

• Consider switching patients who use injectable testosterone to transdermal products.
• Advise patients with a BMI greater than 25 kg/m2 to lose weight to attain a BMI of 18.5-25.
• Advise patients to stop smoking.
• Pursue treatment optimization for chronic lung disease or sleep apnea.

The study had no external funding. The authors reported no relevant financial relationships.

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