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Meta-analysis confirms neuroprotective benefit of metformin
Key takeaways
, according to a systematic review and meta-analysis of longitudinal data.
However, the heterogeneity between the available studies and the potential heterogeneity of diagnostic criteria may mean that validation studies are needed.
Why is this important?
Data suggest that metformin, the most commonly prescribed antidiabetic drug, may be neuroprotective, while diabetes is associated with an excess risk of neurodegenerative disease. Results of studies conducted specifically to investigate the benefit of the antidiabetic drug on cognitive prognosis have been unclear. A meta-analysis was published in 2020, but it included cross-sectional and case-control studies. Given the long observation period needed to measure such an outcome, only cohort studies conducted over several years can provide reliable results. This new meta-analysis attempts to circumvent this limitation.
Methods
The meta-analysis was conducted using studies published up to March 2021 that met the inclusion criteria (population-based cohort studies published in English in which the administration of metformin and associated risk of exposure were reported).
Main results
Twelve studies were included in this analysis, of which eight were retrospective and 11 were considered to be of good methodologic quality. In total, 194,792 patients were included.
Pooled data showed that the relative risk associated with onset of neurodegenerative disease was 0.77 (95% CI, 0.67-0.88) for patients with diabetes taking metformin versus those not taking metformin. However, heterogeneity between studies was high (I2; 78.8%; P < .001).
The effect was greater with longer metformin use, with an RR of 0.29 (95% CI, 0.13-0.44) for those who took metformin for 4 years or more. Similarly, the studies conducted in Asian countries versus other locations suggested an added benefit for this population (RR, 0.69; 95% CI, 0.64-0.74).
Sensitivity analyses confirmed these results, and subtype analyses showed no difference according to the nature of the neurodegenerative disease.
A version of this article first appeared on Univadis.
Key takeaways
, according to a systematic review and meta-analysis of longitudinal data.
However, the heterogeneity between the available studies and the potential heterogeneity of diagnostic criteria may mean that validation studies are needed.
Why is this important?
Data suggest that metformin, the most commonly prescribed antidiabetic drug, may be neuroprotective, while diabetes is associated with an excess risk of neurodegenerative disease. Results of studies conducted specifically to investigate the benefit of the antidiabetic drug on cognitive prognosis have been unclear. A meta-analysis was published in 2020, but it included cross-sectional and case-control studies. Given the long observation period needed to measure such an outcome, only cohort studies conducted over several years can provide reliable results. This new meta-analysis attempts to circumvent this limitation.
Methods
The meta-analysis was conducted using studies published up to March 2021 that met the inclusion criteria (population-based cohort studies published in English in which the administration of metformin and associated risk of exposure were reported).
Main results
Twelve studies were included in this analysis, of which eight were retrospective and 11 were considered to be of good methodologic quality. In total, 194,792 patients were included.
Pooled data showed that the relative risk associated with onset of neurodegenerative disease was 0.77 (95% CI, 0.67-0.88) for patients with diabetes taking metformin versus those not taking metformin. However, heterogeneity between studies was high (I2; 78.8%; P < .001).
The effect was greater with longer metformin use, with an RR of 0.29 (95% CI, 0.13-0.44) for those who took metformin for 4 years or more. Similarly, the studies conducted in Asian countries versus other locations suggested an added benefit for this population (RR, 0.69; 95% CI, 0.64-0.74).
Sensitivity analyses confirmed these results, and subtype analyses showed no difference according to the nature of the neurodegenerative disease.
A version of this article first appeared on Univadis.
Key takeaways
, according to a systematic review and meta-analysis of longitudinal data.
However, the heterogeneity between the available studies and the potential heterogeneity of diagnostic criteria may mean that validation studies are needed.
Why is this important?
Data suggest that metformin, the most commonly prescribed antidiabetic drug, may be neuroprotective, while diabetes is associated with an excess risk of neurodegenerative disease. Results of studies conducted specifically to investigate the benefit of the antidiabetic drug on cognitive prognosis have been unclear. A meta-analysis was published in 2020, but it included cross-sectional and case-control studies. Given the long observation period needed to measure such an outcome, only cohort studies conducted over several years can provide reliable results. This new meta-analysis attempts to circumvent this limitation.
Methods
The meta-analysis was conducted using studies published up to March 2021 that met the inclusion criteria (population-based cohort studies published in English in which the administration of metformin and associated risk of exposure were reported).
Main results
Twelve studies were included in this analysis, of which eight were retrospective and 11 were considered to be of good methodologic quality. In total, 194,792 patients were included.
Pooled data showed that the relative risk associated with onset of neurodegenerative disease was 0.77 (95% CI, 0.67-0.88) for patients with diabetes taking metformin versus those not taking metformin. However, heterogeneity between studies was high (I2; 78.8%; P < .001).
The effect was greater with longer metformin use, with an RR of 0.29 (95% CI, 0.13-0.44) for those who took metformin for 4 years or more. Similarly, the studies conducted in Asian countries versus other locations suggested an added benefit for this population (RR, 0.69; 95% CI, 0.64-0.74).
Sensitivity analyses confirmed these results, and subtype analyses showed no difference according to the nature of the neurodegenerative disease.
A version of this article first appeared on Univadis.
Long-term cannabis use linked to dementia risk factors
A large prospective, longitudinal study showed long-term cannabis users had an intelligence quotient (IQ) decline from age 18 to midlife (mean, 5.5 IQ points), poorer learning and processing speed, compared with childhood, and self-reported memory and attention problems. Long-term cannabis users also showed hippocampal atrophy at midlife (age 45), which combined with mild midlife cognitive deficits, all known risk factors for dementia.
“Long-term cannabis users – people who have used cannabis from 18 or 19 years old and continued using through midlife – showed cognitive deficits, compared with nonusers. They also showed more severe cognitive deficits, compared with long-term alcohol users and long-term tobacco users. But people who used infrequently or recreationally in midlife did not show as severe cognitive deficits. Cognitive deficits were confined to cannabis users,” lead investigator Madeline Meier, PhD, associate professor of psychology, Arizona State University, Tempe, said in an interview.
“Long-term cannabis users had smaller hippocampal volume, but we also found that smaller hippocampal volume did not explain the cognitive deficits among the long-term cannabis users,” she added.
The study was recently published online in the American Journal of Psychiatry.
Growing use in Boomers
Long-term cannabis use has been associated with memory problems. Studies examining the impact of cannabis use on the brain have shown conflicting results. Some suggest regular use in adolescence is associated with altered connectivity and reduced volume of brain regions involved in executive functions such as memory, learning, and impulse control compared with those who do not use cannabis.
Others found no significant structural differences between the brains of cannabis users and nonusers.
An earlier, large longitudinal study in New Zealand found that persistent cannabis use (with frequent use starting in adolescence) was associated with a loss of an average of six (or up to eight) IQ points measured in mid-adulthood.
Cannabis use is increasing among Baby Boomers – a group born between 1946 and 1964 – who used cannabis at historically high rates as young adults, and who now use it at historically high rates in midlife and as older adults.
To date, case-control studies, which are predominantly in adolescents and young adults, have found that cannabis users show subtle cognitive deficits and structural brain differences, but it is unclear whether these differences in young cannabis users might be larger in midlife and in older adults who have longer histories of use.
The study included a representative cohort of 1,037 individuals in Dunedin, New Zealand, born between April 1972 and March 1973, and followed from age 3 to 45.
Cannabis use and dependence were assessed at ages 18, 21, 26, 32, 38, and 45. IQ was assessed at ages 7, 9, 11, and 45. Specific neuropsychological functions and hippocampal volume were assessed at age 45.
“Most of the previous research has focused on adolescent and young-adult cannabis users. What we’re looking at here is long-term cannabis users in midlife, and we’re finding that long-term users show cognitive deficits. But we’re not just looking at a snapshot of people in midlife, we’re also doing a longitudinal comparison – comparing them to themselves in childhood. We saw that long-term cannabis users showed a decline in IQ from childhood to adulthood,” said Dr. Meier.
Participants in the study are members of the Dunedin Longitudinal Study, a representative birth cohort (n = 1,037; 91% of eligible births; 52% male) born between April 1972 and March 1973 in Dunedin, New Zealand, who participated in the first assessment at age 3.
This cohort matched socioeconomic status (SES), key health indicators, and demographics. Assessments were carried out at birth and ages 3, 5, 7, 9, 11, 13, 15, 18, 21, 26, 32, 38, and 45. IQ was assessed at ages 7, 9, 11, and 45. Specific neuropsychological functions and hippocampal volume were assessed at age 45.
Shrinking hippocampal volume
Cannabis use, cognitive function, and hippocampal volume were assessed comparing long-term cannabis users (n = 84) against five distinct groups:
- Lifelong cannabis nonusers (n = 196) – to replicate the control group most often reported in the case-control literature
- Midlife recreational cannabis users (n = 65) – to determine if cognitive deficits and structural brain differences are apparent in nonproblem users – the majority of cannabis users
- Long-term tobacco users (n = 75)
- Long-term alcohol users (n = 57) – benchmark comparisons for any cannabis findings and to disentangle potential cannabis effects from tobacco and alcohol effects
- Cannabis quitters (n = 58) – to determine whether differences are apparent after cessation
Tests were conducted on dose-response associations using continuously measured persistence of cannabis use, rigorously adjusting for numerous confounders derived from multiple longitudinal waves and data sources.
The investigators also tested whether associations between continuously measured persistence of cannabis use and cognitive deficits were mediated by hippocampal volume differences.
The hippocampus was the area of focus because it has a high density of cannabinoid receptors and is also instrumental for learning and memory, which is one of the most consistently impaired cognitive domains in cannabis users, and has been the brain region that most consistently emerges as smaller in cannabis users relative to controls. Structural MRI was done at age 45 for 875 participants (93% of age 45 participants).
Of 997 cohort members still alive at age 45, 938 (94.1%) were assessed at age 45. Age 45 participants did not differ significantly from other participants on childhood SES, childhood self-control, or childhood IQ. Cognitive functioning among midlife recreational cannabis users was similar to representative cohort norms, suggesting that infrequent recreational cannabis use in midlife is unlikely to compromise cognitive functioning.
However, long-term cannabis users did not perform significantly worse on any test than cannabis quitters. Cannabis quitters showed subtle cognitive deficits that may explain inconsistent findings on the benefits of cessation.
Smaller hippocampal volume is thought to be a possible mediator of cannabis-related cognitive deficits because the hippocampus is rich in CB1 receptors and is involved in learning and memory.
Long-term cannabis users had smaller bilateral volume in total hippocampus and 5 of 12 structurally and functionally distinct subregions (tail, hippocampal amygdala transition area, CA1, molecular layer, and dentate gyrus), and significantly smaller volumes than midlife recreational cannabis users in the left and right hippocampus, and 3 of 12 subfields (tail, CA1, and molecular layer), compared with non-users, consistent with case-control studies.
More potent
“If you’ve been using cannabis very long term and now are in midlife, you might want to consider quitting. Quitting is associated with slightly better cognitive performance in midlife. We also need to watch for risk of dementia. We know that people who show cognitive deficits at midlife are at elevated risk for later life dementia. And the deficits we saw among long-term cannabis users (although fairly mild), they were in the range in terms of effect size of what we see among people in other studies who have gone on to develop dementia in later life,” said Dr. Meier.
The study findings conflict with those of other studies, including one by the same research group, which compared the cognitive functioning of twins who were discordant for cannabis use and found little evidence of cannabis-related cognitive deficits. Because long-term cannabis users also use tobacco, alcohol, and other illicit drugs, disentangling cannabis effects from other substances is challenging.
“Long-term cannabis users tend to be long-term polysubstance users, so it’s hard to isolate,” said Dr. Meier.
Additionally, some group sizes were small, raising concerns about low statistical power.
“Group sizes were small but we didn’t rely only on those group comparisons; however, we did find statistical differences. We also tested highly statistically powered dose-response associations between persistence of cannabis use over ages 18-45 and each of our outcomes (IQ, learning, and processing speed in midlife) while adjusting possible alternate explanations such as low childhood IQ, other substance use, [and] socioeconomic backgrounds.
“These dose-response associations used large sample sizes, were highly powered, and took into account a number of alternative explanations. These two different approaches showed very similar findings and one bolstered the other,” said Dr. Meier.
The study’s results were based on individuals who began using cannabis in the 1980s or ‘90s, but the concentration of tetrahydrocannabinol (THC) has risen in recent years.
“When the study began, THC concentration was approximately 4%. Over the last decade we have seen it go up to 12% or even higher. A recent study surveying U.S. dispensaries found 20% THC. If THC accounts for impairment, then the effects can be larger [with higher concentrations]. One of the challenges in the U.S. is that there are laws prohibiting researchers from testing cannabis, so we have to rely on product labels, which we know are unreliable,” said Dr. Meier.
A separate report is forthcoming with results of exploratory analyses of associations between long-term cannabis use and comprehensive MRI measures of global and regional gray and white matter.
The data will also be used to answer a number of different questions about cognitive deficits, brain structure, aging preparedness, social preparedness (strength of social networks), financial and health preparedness, and biological aging (the pace of aging relative to chronological age) in long-term cannabis users, Dr. Meier noted.
‘Fantastic’ research
Commenting on the research for this news organization , Andrew J. Saxon, MD, professor, department of psychiatry & behavioral sciences at University of Washington, Seattle, and a member of the American Psychiatric Association’s Council on Addiction Psychiatry, said the study “provides more evidence that heavy and regular cannabis use is not benign behavior.”
“It’s a fantastic piece of research in which they enrolled participants at birth and have followed them up to age 45. In most of the other research that has been done, we have no idea what their baseline was. What’s so remarkable here is that they can clearly demonstrate the loss of IQ points from childhood to age 45,” said Dr. Saxon.
“It is clear that, in people using cannabis long term, cognition is impaired. It would be good to have a better handle on how much cognitive function can be regained if you quit, because that could be a motivator for quitting in people where cannabis is having an adverse effect on their lives,” he added.
On the issue of THC potency, Dr. Saxon said that, while it’s true the potency of cannabis is increasing in terms of THC concentrations, the question is: “Do people who use cannabis use a set amount or do they imbibe until they achieve the state of altered consciousness that they’re seeking? Although there has been some research in the area of self-regulation and cannabis potency, we do not yet have the answers to determine if there is any causation,” said Dr. Saxon.
Dr. Meier and Dr. Saxon reported no relevant financial conflicts of interest.
A version of this article first appeared on Medscape.com.
A large prospective, longitudinal study showed long-term cannabis users had an intelligence quotient (IQ) decline from age 18 to midlife (mean, 5.5 IQ points), poorer learning and processing speed, compared with childhood, and self-reported memory and attention problems. Long-term cannabis users also showed hippocampal atrophy at midlife (age 45), which combined with mild midlife cognitive deficits, all known risk factors for dementia.
“Long-term cannabis users – people who have used cannabis from 18 or 19 years old and continued using through midlife – showed cognitive deficits, compared with nonusers. They also showed more severe cognitive deficits, compared with long-term alcohol users and long-term tobacco users. But people who used infrequently or recreationally in midlife did not show as severe cognitive deficits. Cognitive deficits were confined to cannabis users,” lead investigator Madeline Meier, PhD, associate professor of psychology, Arizona State University, Tempe, said in an interview.
“Long-term cannabis users had smaller hippocampal volume, but we also found that smaller hippocampal volume did not explain the cognitive deficits among the long-term cannabis users,” she added.
The study was recently published online in the American Journal of Psychiatry.
Growing use in Boomers
Long-term cannabis use has been associated with memory problems. Studies examining the impact of cannabis use on the brain have shown conflicting results. Some suggest regular use in adolescence is associated with altered connectivity and reduced volume of brain regions involved in executive functions such as memory, learning, and impulse control compared with those who do not use cannabis.
Others found no significant structural differences between the brains of cannabis users and nonusers.
An earlier, large longitudinal study in New Zealand found that persistent cannabis use (with frequent use starting in adolescence) was associated with a loss of an average of six (or up to eight) IQ points measured in mid-adulthood.
Cannabis use is increasing among Baby Boomers – a group born between 1946 and 1964 – who used cannabis at historically high rates as young adults, and who now use it at historically high rates in midlife and as older adults.
To date, case-control studies, which are predominantly in adolescents and young adults, have found that cannabis users show subtle cognitive deficits and structural brain differences, but it is unclear whether these differences in young cannabis users might be larger in midlife and in older adults who have longer histories of use.
The study included a representative cohort of 1,037 individuals in Dunedin, New Zealand, born between April 1972 and March 1973, and followed from age 3 to 45.
Cannabis use and dependence were assessed at ages 18, 21, 26, 32, 38, and 45. IQ was assessed at ages 7, 9, 11, and 45. Specific neuropsychological functions and hippocampal volume were assessed at age 45.
“Most of the previous research has focused on adolescent and young-adult cannabis users. What we’re looking at here is long-term cannabis users in midlife, and we’re finding that long-term users show cognitive deficits. But we’re not just looking at a snapshot of people in midlife, we’re also doing a longitudinal comparison – comparing them to themselves in childhood. We saw that long-term cannabis users showed a decline in IQ from childhood to adulthood,” said Dr. Meier.
Participants in the study are members of the Dunedin Longitudinal Study, a representative birth cohort (n = 1,037; 91% of eligible births; 52% male) born between April 1972 and March 1973 in Dunedin, New Zealand, who participated in the first assessment at age 3.
This cohort matched socioeconomic status (SES), key health indicators, and demographics. Assessments were carried out at birth and ages 3, 5, 7, 9, 11, 13, 15, 18, 21, 26, 32, 38, and 45. IQ was assessed at ages 7, 9, 11, and 45. Specific neuropsychological functions and hippocampal volume were assessed at age 45.
Shrinking hippocampal volume
Cannabis use, cognitive function, and hippocampal volume were assessed comparing long-term cannabis users (n = 84) against five distinct groups:
- Lifelong cannabis nonusers (n = 196) – to replicate the control group most often reported in the case-control literature
- Midlife recreational cannabis users (n = 65) – to determine if cognitive deficits and structural brain differences are apparent in nonproblem users – the majority of cannabis users
- Long-term tobacco users (n = 75)
- Long-term alcohol users (n = 57) – benchmark comparisons for any cannabis findings and to disentangle potential cannabis effects from tobacco and alcohol effects
- Cannabis quitters (n = 58) – to determine whether differences are apparent after cessation
Tests were conducted on dose-response associations using continuously measured persistence of cannabis use, rigorously adjusting for numerous confounders derived from multiple longitudinal waves and data sources.
The investigators also tested whether associations between continuously measured persistence of cannabis use and cognitive deficits were mediated by hippocampal volume differences.
The hippocampus was the area of focus because it has a high density of cannabinoid receptors and is also instrumental for learning and memory, which is one of the most consistently impaired cognitive domains in cannabis users, and has been the brain region that most consistently emerges as smaller in cannabis users relative to controls. Structural MRI was done at age 45 for 875 participants (93% of age 45 participants).
Of 997 cohort members still alive at age 45, 938 (94.1%) were assessed at age 45. Age 45 participants did not differ significantly from other participants on childhood SES, childhood self-control, or childhood IQ. Cognitive functioning among midlife recreational cannabis users was similar to representative cohort norms, suggesting that infrequent recreational cannabis use in midlife is unlikely to compromise cognitive functioning.
However, long-term cannabis users did not perform significantly worse on any test than cannabis quitters. Cannabis quitters showed subtle cognitive deficits that may explain inconsistent findings on the benefits of cessation.
Smaller hippocampal volume is thought to be a possible mediator of cannabis-related cognitive deficits because the hippocampus is rich in CB1 receptors and is involved in learning and memory.
Long-term cannabis users had smaller bilateral volume in total hippocampus and 5 of 12 structurally and functionally distinct subregions (tail, hippocampal amygdala transition area, CA1, molecular layer, and dentate gyrus), and significantly smaller volumes than midlife recreational cannabis users in the left and right hippocampus, and 3 of 12 subfields (tail, CA1, and molecular layer), compared with non-users, consistent with case-control studies.
More potent
“If you’ve been using cannabis very long term and now are in midlife, you might want to consider quitting. Quitting is associated with slightly better cognitive performance in midlife. We also need to watch for risk of dementia. We know that people who show cognitive deficits at midlife are at elevated risk for later life dementia. And the deficits we saw among long-term cannabis users (although fairly mild), they were in the range in terms of effect size of what we see among people in other studies who have gone on to develop dementia in later life,” said Dr. Meier.
The study findings conflict with those of other studies, including one by the same research group, which compared the cognitive functioning of twins who were discordant for cannabis use and found little evidence of cannabis-related cognitive deficits. Because long-term cannabis users also use tobacco, alcohol, and other illicit drugs, disentangling cannabis effects from other substances is challenging.
“Long-term cannabis users tend to be long-term polysubstance users, so it’s hard to isolate,” said Dr. Meier.
Additionally, some group sizes were small, raising concerns about low statistical power.
“Group sizes were small but we didn’t rely only on those group comparisons; however, we did find statistical differences. We also tested highly statistically powered dose-response associations between persistence of cannabis use over ages 18-45 and each of our outcomes (IQ, learning, and processing speed in midlife) while adjusting possible alternate explanations such as low childhood IQ, other substance use, [and] socioeconomic backgrounds.
“These dose-response associations used large sample sizes, were highly powered, and took into account a number of alternative explanations. These two different approaches showed very similar findings and one bolstered the other,” said Dr. Meier.
The study’s results were based on individuals who began using cannabis in the 1980s or ‘90s, but the concentration of tetrahydrocannabinol (THC) has risen in recent years.
“When the study began, THC concentration was approximately 4%. Over the last decade we have seen it go up to 12% or even higher. A recent study surveying U.S. dispensaries found 20% THC. If THC accounts for impairment, then the effects can be larger [with higher concentrations]. One of the challenges in the U.S. is that there are laws prohibiting researchers from testing cannabis, so we have to rely on product labels, which we know are unreliable,” said Dr. Meier.
A separate report is forthcoming with results of exploratory analyses of associations between long-term cannabis use and comprehensive MRI measures of global and regional gray and white matter.
The data will also be used to answer a number of different questions about cognitive deficits, brain structure, aging preparedness, social preparedness (strength of social networks), financial and health preparedness, and biological aging (the pace of aging relative to chronological age) in long-term cannabis users, Dr. Meier noted.
‘Fantastic’ research
Commenting on the research for this news organization , Andrew J. Saxon, MD, professor, department of psychiatry & behavioral sciences at University of Washington, Seattle, and a member of the American Psychiatric Association’s Council on Addiction Psychiatry, said the study “provides more evidence that heavy and regular cannabis use is not benign behavior.”
“It’s a fantastic piece of research in which they enrolled participants at birth and have followed them up to age 45. In most of the other research that has been done, we have no idea what their baseline was. What’s so remarkable here is that they can clearly demonstrate the loss of IQ points from childhood to age 45,” said Dr. Saxon.
“It is clear that, in people using cannabis long term, cognition is impaired. It would be good to have a better handle on how much cognitive function can be regained if you quit, because that could be a motivator for quitting in people where cannabis is having an adverse effect on their lives,” he added.
On the issue of THC potency, Dr. Saxon said that, while it’s true the potency of cannabis is increasing in terms of THC concentrations, the question is: “Do people who use cannabis use a set amount or do they imbibe until they achieve the state of altered consciousness that they’re seeking? Although there has been some research in the area of self-regulation and cannabis potency, we do not yet have the answers to determine if there is any causation,” said Dr. Saxon.
Dr. Meier and Dr. Saxon reported no relevant financial conflicts of interest.
A version of this article first appeared on Medscape.com.
A large prospective, longitudinal study showed long-term cannabis users had an intelligence quotient (IQ) decline from age 18 to midlife (mean, 5.5 IQ points), poorer learning and processing speed, compared with childhood, and self-reported memory and attention problems. Long-term cannabis users also showed hippocampal atrophy at midlife (age 45), which combined with mild midlife cognitive deficits, all known risk factors for dementia.
“Long-term cannabis users – people who have used cannabis from 18 or 19 years old and continued using through midlife – showed cognitive deficits, compared with nonusers. They also showed more severe cognitive deficits, compared with long-term alcohol users and long-term tobacco users. But people who used infrequently or recreationally in midlife did not show as severe cognitive deficits. Cognitive deficits were confined to cannabis users,” lead investigator Madeline Meier, PhD, associate professor of psychology, Arizona State University, Tempe, said in an interview.
“Long-term cannabis users had smaller hippocampal volume, but we also found that smaller hippocampal volume did not explain the cognitive deficits among the long-term cannabis users,” she added.
The study was recently published online in the American Journal of Psychiatry.
Growing use in Boomers
Long-term cannabis use has been associated with memory problems. Studies examining the impact of cannabis use on the brain have shown conflicting results. Some suggest regular use in adolescence is associated with altered connectivity and reduced volume of brain regions involved in executive functions such as memory, learning, and impulse control compared with those who do not use cannabis.
Others found no significant structural differences between the brains of cannabis users and nonusers.
An earlier, large longitudinal study in New Zealand found that persistent cannabis use (with frequent use starting in adolescence) was associated with a loss of an average of six (or up to eight) IQ points measured in mid-adulthood.
Cannabis use is increasing among Baby Boomers – a group born between 1946 and 1964 – who used cannabis at historically high rates as young adults, and who now use it at historically high rates in midlife and as older adults.
To date, case-control studies, which are predominantly in adolescents and young adults, have found that cannabis users show subtle cognitive deficits and structural brain differences, but it is unclear whether these differences in young cannabis users might be larger in midlife and in older adults who have longer histories of use.
The study included a representative cohort of 1,037 individuals in Dunedin, New Zealand, born between April 1972 and March 1973, and followed from age 3 to 45.
Cannabis use and dependence were assessed at ages 18, 21, 26, 32, 38, and 45. IQ was assessed at ages 7, 9, 11, and 45. Specific neuropsychological functions and hippocampal volume were assessed at age 45.
“Most of the previous research has focused on adolescent and young-adult cannabis users. What we’re looking at here is long-term cannabis users in midlife, and we’re finding that long-term users show cognitive deficits. But we’re not just looking at a snapshot of people in midlife, we’re also doing a longitudinal comparison – comparing them to themselves in childhood. We saw that long-term cannabis users showed a decline in IQ from childhood to adulthood,” said Dr. Meier.
Participants in the study are members of the Dunedin Longitudinal Study, a representative birth cohort (n = 1,037; 91% of eligible births; 52% male) born between April 1972 and March 1973 in Dunedin, New Zealand, who participated in the first assessment at age 3.
This cohort matched socioeconomic status (SES), key health indicators, and demographics. Assessments were carried out at birth and ages 3, 5, 7, 9, 11, 13, 15, 18, 21, 26, 32, 38, and 45. IQ was assessed at ages 7, 9, 11, and 45. Specific neuropsychological functions and hippocampal volume were assessed at age 45.
Shrinking hippocampal volume
Cannabis use, cognitive function, and hippocampal volume were assessed comparing long-term cannabis users (n = 84) against five distinct groups:
- Lifelong cannabis nonusers (n = 196) – to replicate the control group most often reported in the case-control literature
- Midlife recreational cannabis users (n = 65) – to determine if cognitive deficits and structural brain differences are apparent in nonproblem users – the majority of cannabis users
- Long-term tobacco users (n = 75)
- Long-term alcohol users (n = 57) – benchmark comparisons for any cannabis findings and to disentangle potential cannabis effects from tobacco and alcohol effects
- Cannabis quitters (n = 58) – to determine whether differences are apparent after cessation
Tests were conducted on dose-response associations using continuously measured persistence of cannabis use, rigorously adjusting for numerous confounders derived from multiple longitudinal waves and data sources.
The investigators also tested whether associations between continuously measured persistence of cannabis use and cognitive deficits were mediated by hippocampal volume differences.
The hippocampus was the area of focus because it has a high density of cannabinoid receptors and is also instrumental for learning and memory, which is one of the most consistently impaired cognitive domains in cannabis users, and has been the brain region that most consistently emerges as smaller in cannabis users relative to controls. Structural MRI was done at age 45 for 875 participants (93% of age 45 participants).
Of 997 cohort members still alive at age 45, 938 (94.1%) were assessed at age 45. Age 45 participants did not differ significantly from other participants on childhood SES, childhood self-control, or childhood IQ. Cognitive functioning among midlife recreational cannabis users was similar to representative cohort norms, suggesting that infrequent recreational cannabis use in midlife is unlikely to compromise cognitive functioning.
However, long-term cannabis users did not perform significantly worse on any test than cannabis quitters. Cannabis quitters showed subtle cognitive deficits that may explain inconsistent findings on the benefits of cessation.
Smaller hippocampal volume is thought to be a possible mediator of cannabis-related cognitive deficits because the hippocampus is rich in CB1 receptors and is involved in learning and memory.
Long-term cannabis users had smaller bilateral volume in total hippocampus and 5 of 12 structurally and functionally distinct subregions (tail, hippocampal amygdala transition area, CA1, molecular layer, and dentate gyrus), and significantly smaller volumes than midlife recreational cannabis users in the left and right hippocampus, and 3 of 12 subfields (tail, CA1, and molecular layer), compared with non-users, consistent with case-control studies.
More potent
“If you’ve been using cannabis very long term and now are in midlife, you might want to consider quitting. Quitting is associated with slightly better cognitive performance in midlife. We also need to watch for risk of dementia. We know that people who show cognitive deficits at midlife are at elevated risk for later life dementia. And the deficits we saw among long-term cannabis users (although fairly mild), they were in the range in terms of effect size of what we see among people in other studies who have gone on to develop dementia in later life,” said Dr. Meier.
The study findings conflict with those of other studies, including one by the same research group, which compared the cognitive functioning of twins who were discordant for cannabis use and found little evidence of cannabis-related cognitive deficits. Because long-term cannabis users also use tobacco, alcohol, and other illicit drugs, disentangling cannabis effects from other substances is challenging.
“Long-term cannabis users tend to be long-term polysubstance users, so it’s hard to isolate,” said Dr. Meier.
Additionally, some group sizes were small, raising concerns about low statistical power.
“Group sizes were small but we didn’t rely only on those group comparisons; however, we did find statistical differences. We also tested highly statistically powered dose-response associations between persistence of cannabis use over ages 18-45 and each of our outcomes (IQ, learning, and processing speed in midlife) while adjusting possible alternate explanations such as low childhood IQ, other substance use, [and] socioeconomic backgrounds.
“These dose-response associations used large sample sizes, were highly powered, and took into account a number of alternative explanations. These two different approaches showed very similar findings and one bolstered the other,” said Dr. Meier.
The study’s results were based on individuals who began using cannabis in the 1980s or ‘90s, but the concentration of tetrahydrocannabinol (THC) has risen in recent years.
“When the study began, THC concentration was approximately 4%. Over the last decade we have seen it go up to 12% or even higher. A recent study surveying U.S. dispensaries found 20% THC. If THC accounts for impairment, then the effects can be larger [with higher concentrations]. One of the challenges in the U.S. is that there are laws prohibiting researchers from testing cannabis, so we have to rely on product labels, which we know are unreliable,” said Dr. Meier.
A separate report is forthcoming with results of exploratory analyses of associations between long-term cannabis use and comprehensive MRI measures of global and regional gray and white matter.
The data will also be used to answer a number of different questions about cognitive deficits, brain structure, aging preparedness, social preparedness (strength of social networks), financial and health preparedness, and biological aging (the pace of aging relative to chronological age) in long-term cannabis users, Dr. Meier noted.
‘Fantastic’ research
Commenting on the research for this news organization , Andrew J. Saxon, MD, professor, department of psychiatry & behavioral sciences at University of Washington, Seattle, and a member of the American Psychiatric Association’s Council on Addiction Psychiatry, said the study “provides more evidence that heavy and regular cannabis use is not benign behavior.”
“It’s a fantastic piece of research in which they enrolled participants at birth and have followed them up to age 45. In most of the other research that has been done, we have no idea what their baseline was. What’s so remarkable here is that they can clearly demonstrate the loss of IQ points from childhood to age 45,” said Dr. Saxon.
“It is clear that, in people using cannabis long term, cognition is impaired. It would be good to have a better handle on how much cognitive function can be regained if you quit, because that could be a motivator for quitting in people where cannabis is having an adverse effect on their lives,” he added.
On the issue of THC potency, Dr. Saxon said that, while it’s true the potency of cannabis is increasing in terms of THC concentrations, the question is: “Do people who use cannabis use a set amount or do they imbibe until they achieve the state of altered consciousness that they’re seeking? Although there has been some research in the area of self-regulation and cannabis potency, we do not yet have the answers to determine if there is any causation,” said Dr. Saxon.
Dr. Meier and Dr. Saxon reported no relevant financial conflicts of interest.
A version of this article first appeared on Medscape.com.
FROM THE AMERICAN JOURNAL OF PSYCHIATRY
Antibody reduces amyloid, induces symptom decline
SEATTLE – The researchers identified two plasma biomarkers that correlate well with established amyloid PET standard uptake value ratio (SUVr) changes, potentially paving the way for monitoring lecanemab treatment effects. The researchers also found evidence that the plasma biomarker could be used to allow dose frequency reduction after initial reduction in amyloid plaques.
Lecanemab preferably targets aggregated species of amyloid called protofibrils, which is unique among anti-amyloid antibodies, and these are also among the most toxic manifestations of amyloid, according to Chad Swanson, PhD, who presented the study at the 2022 annual meeting of the American Academy of Neurology.
Are amyloid plaques a key driver of Alzheimer’s disease?
The study could help answer the question of whether amyloid plaques drive the cognitive decline seen in Alzheimer’s disease, in part because the antibody is so effective at what it was designed to do, according to Fernando Testai, MD, PhD, who comoderated the session where the study was presented. “The effect on amyloid content that they measured was persistent over a number of months. Cognition may follow along, so more studies have to be done, but the medication seems to be quite effective doing what it’s supposed to do. If it has something to do with disease, these treatments actually should give us the answer, because the effect on amyloid is pretty significant. After so many years of thinking amyloid probably has nothing to do (with Alzheimer’s symptoms, these results suggest) it may have something to do with the disease,” Dr. Testai said in an interview. He is a professor of neurology at the University of Illinois at Chicago.
Dr. Swanson is confident that amyloid plaques are a key driver of disease. “I’d say a number of companies now with anti-amyloid agents have shown that targeting amyloid can produce some slowing of clinical decline, as well as a robust reduction in amyloid, supporting this idea that that amyloid is meaningful. And it’s very clear that amyloid [deposition] tends to trigger tau pathology,” said Dr. Swanson in an interview. He is executive director of the neurology business group at Eisai Pharmaceuticals, which is developing the anti-amyloid antibody, called lecanemab.
Searching for the best dose and dose frequency
Dr. Swanson noted that Eisai has already conducted a large phase 2b study which informed the current phase 3 ClarityAD study design. The phase 2b study utilized a Bayesian adaptive design, which allocated more patients in a fully blinded way to doses that had the most potential for slowing clinical decline. “The intent was to maximize the efficiency of the design so that more subjects would go to a dose that looks like it could be the best dose according to the Bayesian algorithm,” said Dr. Swanson.
The study also included a gap period that followed the randomized phase of the trial, where subjects were not being dosed with the antibody from 9 to 59 months (mean, 2 years), before reinitiation at the start of the open-label extension phase. “[That] allowed us to answer some really important questions about what happens when you remove lecanemab after reducing amyloid, and then what happens when you reintroduce lecanemab in the open-label extension,” said Dr. Swanson.
The researchers found that amyloid reaccumulated during the treatment gap, and soluble biomarkers were potentially the most sensitive to the change. “Taking all of this information together with clinical data that suggest potential disease-modifying effects, it suggests that we need to continue to treat these individuals, but we may be able to treat with a less-frequent dosing interval once amyloid is removed from the brain. It’s a biweekly infusion. Following 18 months of treatment, we may be able to go in once every month or once every 3 months to maintain low levels of amyloid. We’re going to be testing that soon in the current phase 2 open-label extension,” said Dr. Swanson.
The study included 856 patients who were randomized to biweekly placebo or lecanemab 2.5 mg/kg biweekly, 5 mg/kg monthly, 5 mg/kg biweekly, 10 mg/kg monthly, or 10 mg/kg biweekly. The primary endpoint was the Alzheimer’s disease composite score at 12 months; secondary endpoints included ADCOMS and various biomarker levels at 18 months.
At 18 months, the 10-mg/kg biweekly group had an adjusted mean change from placebo in brain amyloid of –0.31 SUVr units, with more than 80% of the subjects converting from amyloid positive to amyloid negative by visual read. Most subjects remained amyloid negative at open-label extension baseline following the gap period despite a slow reaccumulation of amyloid plaque in the treated group. Out to 18 months in the core study, the same group had a 30% reduction in cognitive decline, compared with placebo, as measured by ADCOMS (P < .05).
There was a correlation between PET SUVr, clinical outcomes, and the Abeta42/40 ratio and plasma p-tau181. During the gap period, treatment discontinuation was associated with changes in the plasma biomarkers that echoed amyloid re-accumulation and clinical decline. Change from baseline in both plasma biomarkers were associated with a change from baseline in PET SUVr at 18 months.
Amyloid-related imaging abnormalities related to brain edema or sulcal effusion (ARIA-E) occurred in 9.9% of patients during the randomized phase of the trial, and 7.8% during the open-label extension phase. About 2% were symptomatic in both the randomization and open-label extension phases. The majority of ARIA-E cases appeared within 3 months of treatment initiation, and generally resolved in 4-16 weeks. 80% were mild to moderate by radiography.
Dr. Swanson is an employee of Eisai Pharmaceuticals, which sponsored the study. Dr. Testai has no relevant financial disclosures.
SEATTLE – The researchers identified two plasma biomarkers that correlate well with established amyloid PET standard uptake value ratio (SUVr) changes, potentially paving the way for monitoring lecanemab treatment effects. The researchers also found evidence that the plasma biomarker could be used to allow dose frequency reduction after initial reduction in amyloid plaques.
Lecanemab preferably targets aggregated species of amyloid called protofibrils, which is unique among anti-amyloid antibodies, and these are also among the most toxic manifestations of amyloid, according to Chad Swanson, PhD, who presented the study at the 2022 annual meeting of the American Academy of Neurology.
Are amyloid plaques a key driver of Alzheimer’s disease?
The study could help answer the question of whether amyloid plaques drive the cognitive decline seen in Alzheimer’s disease, in part because the antibody is so effective at what it was designed to do, according to Fernando Testai, MD, PhD, who comoderated the session where the study was presented. “The effect on amyloid content that they measured was persistent over a number of months. Cognition may follow along, so more studies have to be done, but the medication seems to be quite effective doing what it’s supposed to do. If it has something to do with disease, these treatments actually should give us the answer, because the effect on amyloid is pretty significant. After so many years of thinking amyloid probably has nothing to do (with Alzheimer’s symptoms, these results suggest) it may have something to do with the disease,” Dr. Testai said in an interview. He is a professor of neurology at the University of Illinois at Chicago.
Dr. Swanson is confident that amyloid plaques are a key driver of disease. “I’d say a number of companies now with anti-amyloid agents have shown that targeting amyloid can produce some slowing of clinical decline, as well as a robust reduction in amyloid, supporting this idea that that amyloid is meaningful. And it’s very clear that amyloid [deposition] tends to trigger tau pathology,” said Dr. Swanson in an interview. He is executive director of the neurology business group at Eisai Pharmaceuticals, which is developing the anti-amyloid antibody, called lecanemab.
Searching for the best dose and dose frequency
Dr. Swanson noted that Eisai has already conducted a large phase 2b study which informed the current phase 3 ClarityAD study design. The phase 2b study utilized a Bayesian adaptive design, which allocated more patients in a fully blinded way to doses that had the most potential for slowing clinical decline. “The intent was to maximize the efficiency of the design so that more subjects would go to a dose that looks like it could be the best dose according to the Bayesian algorithm,” said Dr. Swanson.
The study also included a gap period that followed the randomized phase of the trial, where subjects were not being dosed with the antibody from 9 to 59 months (mean, 2 years), before reinitiation at the start of the open-label extension phase. “[That] allowed us to answer some really important questions about what happens when you remove lecanemab after reducing amyloid, and then what happens when you reintroduce lecanemab in the open-label extension,” said Dr. Swanson.
The researchers found that amyloid reaccumulated during the treatment gap, and soluble biomarkers were potentially the most sensitive to the change. “Taking all of this information together with clinical data that suggest potential disease-modifying effects, it suggests that we need to continue to treat these individuals, but we may be able to treat with a less-frequent dosing interval once amyloid is removed from the brain. It’s a biweekly infusion. Following 18 months of treatment, we may be able to go in once every month or once every 3 months to maintain low levels of amyloid. We’re going to be testing that soon in the current phase 2 open-label extension,” said Dr. Swanson.
The study included 856 patients who were randomized to biweekly placebo or lecanemab 2.5 mg/kg biweekly, 5 mg/kg monthly, 5 mg/kg biweekly, 10 mg/kg monthly, or 10 mg/kg biweekly. The primary endpoint was the Alzheimer’s disease composite score at 12 months; secondary endpoints included ADCOMS and various biomarker levels at 18 months.
At 18 months, the 10-mg/kg biweekly group had an adjusted mean change from placebo in brain amyloid of –0.31 SUVr units, with more than 80% of the subjects converting from amyloid positive to amyloid negative by visual read. Most subjects remained amyloid negative at open-label extension baseline following the gap period despite a slow reaccumulation of amyloid plaque in the treated group. Out to 18 months in the core study, the same group had a 30% reduction in cognitive decline, compared with placebo, as measured by ADCOMS (P < .05).
There was a correlation between PET SUVr, clinical outcomes, and the Abeta42/40 ratio and plasma p-tau181. During the gap period, treatment discontinuation was associated with changes in the plasma biomarkers that echoed amyloid re-accumulation and clinical decline. Change from baseline in both plasma biomarkers were associated with a change from baseline in PET SUVr at 18 months.
Amyloid-related imaging abnormalities related to brain edema or sulcal effusion (ARIA-E) occurred in 9.9% of patients during the randomized phase of the trial, and 7.8% during the open-label extension phase. About 2% were symptomatic in both the randomization and open-label extension phases. The majority of ARIA-E cases appeared within 3 months of treatment initiation, and generally resolved in 4-16 weeks. 80% were mild to moderate by radiography.
Dr. Swanson is an employee of Eisai Pharmaceuticals, which sponsored the study. Dr. Testai has no relevant financial disclosures.
SEATTLE – The researchers identified two plasma biomarkers that correlate well with established amyloid PET standard uptake value ratio (SUVr) changes, potentially paving the way for monitoring lecanemab treatment effects. The researchers also found evidence that the plasma biomarker could be used to allow dose frequency reduction after initial reduction in amyloid plaques.
Lecanemab preferably targets aggregated species of amyloid called protofibrils, which is unique among anti-amyloid antibodies, and these are also among the most toxic manifestations of amyloid, according to Chad Swanson, PhD, who presented the study at the 2022 annual meeting of the American Academy of Neurology.
Are amyloid plaques a key driver of Alzheimer’s disease?
The study could help answer the question of whether amyloid plaques drive the cognitive decline seen in Alzheimer’s disease, in part because the antibody is so effective at what it was designed to do, according to Fernando Testai, MD, PhD, who comoderated the session where the study was presented. “The effect on amyloid content that they measured was persistent over a number of months. Cognition may follow along, so more studies have to be done, but the medication seems to be quite effective doing what it’s supposed to do. If it has something to do with disease, these treatments actually should give us the answer, because the effect on amyloid is pretty significant. After so many years of thinking amyloid probably has nothing to do (with Alzheimer’s symptoms, these results suggest) it may have something to do with the disease,” Dr. Testai said in an interview. He is a professor of neurology at the University of Illinois at Chicago.
Dr. Swanson is confident that amyloid plaques are a key driver of disease. “I’d say a number of companies now with anti-amyloid agents have shown that targeting amyloid can produce some slowing of clinical decline, as well as a robust reduction in amyloid, supporting this idea that that amyloid is meaningful. And it’s very clear that amyloid [deposition] tends to trigger tau pathology,” said Dr. Swanson in an interview. He is executive director of the neurology business group at Eisai Pharmaceuticals, which is developing the anti-amyloid antibody, called lecanemab.
Searching for the best dose and dose frequency
Dr. Swanson noted that Eisai has already conducted a large phase 2b study which informed the current phase 3 ClarityAD study design. The phase 2b study utilized a Bayesian adaptive design, which allocated more patients in a fully blinded way to doses that had the most potential for slowing clinical decline. “The intent was to maximize the efficiency of the design so that more subjects would go to a dose that looks like it could be the best dose according to the Bayesian algorithm,” said Dr. Swanson.
The study also included a gap period that followed the randomized phase of the trial, where subjects were not being dosed with the antibody from 9 to 59 months (mean, 2 years), before reinitiation at the start of the open-label extension phase. “[That] allowed us to answer some really important questions about what happens when you remove lecanemab after reducing amyloid, and then what happens when you reintroduce lecanemab in the open-label extension,” said Dr. Swanson.
The researchers found that amyloid reaccumulated during the treatment gap, and soluble biomarkers were potentially the most sensitive to the change. “Taking all of this information together with clinical data that suggest potential disease-modifying effects, it suggests that we need to continue to treat these individuals, but we may be able to treat with a less-frequent dosing interval once amyloid is removed from the brain. It’s a biweekly infusion. Following 18 months of treatment, we may be able to go in once every month or once every 3 months to maintain low levels of amyloid. We’re going to be testing that soon in the current phase 2 open-label extension,” said Dr. Swanson.
The study included 856 patients who were randomized to biweekly placebo or lecanemab 2.5 mg/kg biweekly, 5 mg/kg monthly, 5 mg/kg biweekly, 10 mg/kg monthly, or 10 mg/kg biweekly. The primary endpoint was the Alzheimer’s disease composite score at 12 months; secondary endpoints included ADCOMS and various biomarker levels at 18 months.
At 18 months, the 10-mg/kg biweekly group had an adjusted mean change from placebo in brain amyloid of –0.31 SUVr units, with more than 80% of the subjects converting from amyloid positive to amyloid negative by visual read. Most subjects remained amyloid negative at open-label extension baseline following the gap period despite a slow reaccumulation of amyloid plaque in the treated group. Out to 18 months in the core study, the same group had a 30% reduction in cognitive decline, compared with placebo, as measured by ADCOMS (P < .05).
There was a correlation between PET SUVr, clinical outcomes, and the Abeta42/40 ratio and plasma p-tau181. During the gap period, treatment discontinuation was associated with changes in the plasma biomarkers that echoed amyloid re-accumulation and clinical decline. Change from baseline in both plasma biomarkers were associated with a change from baseline in PET SUVr at 18 months.
Amyloid-related imaging abnormalities related to brain edema or sulcal effusion (ARIA-E) occurred in 9.9% of patients during the randomized phase of the trial, and 7.8% during the open-label extension phase. About 2% were symptomatic in both the randomization and open-label extension phases. The majority of ARIA-E cases appeared within 3 months of treatment initiation, and generally resolved in 4-16 weeks. 80% were mild to moderate by radiography.
Dr. Swanson is an employee of Eisai Pharmaceuticals, which sponsored the study. Dr. Testai has no relevant financial disclosures.
AT AAN 2022
The EMR gets it wrong: SNAFU
The medical news is full of articles about the coming epidemic of dementia. How many people will have it in 10 years, 20 years, etc. It’s a very legitimate concern, and I am not going to make light of it, or disagree with the predictions.
In my everyday practice, though, I find there’s an epidemic of overdiagnosed dementia, in those who aren’t even close.
This occurs in a few ways:
Aricept is pretty inexpensive these days. Long off patent, insurance companies don’t bother to question its use anymore. So anyone older than 60 who complains of losing their car keys gets put on it. Why? Because patients want their doctors to DO SOMETHING. Even if the doctor knows that there’s really nothing of alarm going on, sometimes it’s easier to go with the placebo effect than argue. I think we’ve all done that before.
There are also a lot of nonneurologists in practice who still, after almost 30 years on the market, think Aricept improves memory, when in fact that’s far from the truth. The best it can claim to do is slow down the rate at which patients get worse, but nobody wants to hear that.
I’ve also seen Aricept used for pseudodementia due to depression. Actually, I’ve seen it used for depression, too. Sometimes it’s used to counteract the side effects dof drugs that can impair cognition, such as Topamax, even in patients who aren’t even remotely demented.
None of the above are a major issue on their own. Where the trouble really happens, as with so many other things, is when they collide with an EMR, or someone too rushed to take a history, or both.
Let’s say Mrs. Jones is on Aricept because she went into a room, then forgot why she did.
Then she gets admitted to the hospital for pneumonia. Or she changes doctors and, like many practices these days, her medications are put in the computer by an MA or secretary.
A lot of times , so that gets punched in as a diagnosis and the patient is now believed to be unable to provide a reliable history. Or the person entering the info looks up its indication and enters “Alzheimer’s disease.”
Even worse is that I’ve seen EMRs where, in an effort to save time, the computer automatically enters diagnoses as you type medications in, and it’s up to the doctor to review them for accuracy. How that saves time I have no idea. But, as above, in these cases it’s going to lead to an entry of dementia where there isn’t any.
That, in particular, is pretty scary. As I wrote here in January of this year, what happens in the EMR stays in the EMR (kind of like Las Vegas).
I’m not knocking off-label use of medications. I don’t know a doctor who doesn’t use some that way, including myself.
But when doing so leads to the wrong assumptions and diagnoses it creates a lot of problems.
Dr. Block has a solo neurology practice in Scottsdale, Ariz.
The medical news is full of articles about the coming epidemic of dementia. How many people will have it in 10 years, 20 years, etc. It’s a very legitimate concern, and I am not going to make light of it, or disagree with the predictions.
In my everyday practice, though, I find there’s an epidemic of overdiagnosed dementia, in those who aren’t even close.
This occurs in a few ways:
Aricept is pretty inexpensive these days. Long off patent, insurance companies don’t bother to question its use anymore. So anyone older than 60 who complains of losing their car keys gets put on it. Why? Because patients want their doctors to DO SOMETHING. Even if the doctor knows that there’s really nothing of alarm going on, sometimes it’s easier to go with the placebo effect than argue. I think we’ve all done that before.
There are also a lot of nonneurologists in practice who still, after almost 30 years on the market, think Aricept improves memory, when in fact that’s far from the truth. The best it can claim to do is slow down the rate at which patients get worse, but nobody wants to hear that.
I’ve also seen Aricept used for pseudodementia due to depression. Actually, I’ve seen it used for depression, too. Sometimes it’s used to counteract the side effects dof drugs that can impair cognition, such as Topamax, even in patients who aren’t even remotely demented.
None of the above are a major issue on their own. Where the trouble really happens, as with so many other things, is when they collide with an EMR, or someone too rushed to take a history, or both.
Let’s say Mrs. Jones is on Aricept because she went into a room, then forgot why she did.
Then she gets admitted to the hospital for pneumonia. Or she changes doctors and, like many practices these days, her medications are put in the computer by an MA or secretary.
A lot of times , so that gets punched in as a diagnosis and the patient is now believed to be unable to provide a reliable history. Or the person entering the info looks up its indication and enters “Alzheimer’s disease.”
Even worse is that I’ve seen EMRs where, in an effort to save time, the computer automatically enters diagnoses as you type medications in, and it’s up to the doctor to review them for accuracy. How that saves time I have no idea. But, as above, in these cases it’s going to lead to an entry of dementia where there isn’t any.
That, in particular, is pretty scary. As I wrote here in January of this year, what happens in the EMR stays in the EMR (kind of like Las Vegas).
I’m not knocking off-label use of medications. I don’t know a doctor who doesn’t use some that way, including myself.
But when doing so leads to the wrong assumptions and diagnoses it creates a lot of problems.
Dr. Block has a solo neurology practice in Scottsdale, Ariz.
The medical news is full of articles about the coming epidemic of dementia. How many people will have it in 10 years, 20 years, etc. It’s a very legitimate concern, and I am not going to make light of it, or disagree with the predictions.
In my everyday practice, though, I find there’s an epidemic of overdiagnosed dementia, in those who aren’t even close.
This occurs in a few ways:
Aricept is pretty inexpensive these days. Long off patent, insurance companies don’t bother to question its use anymore. So anyone older than 60 who complains of losing their car keys gets put on it. Why? Because patients want their doctors to DO SOMETHING. Even if the doctor knows that there’s really nothing of alarm going on, sometimes it’s easier to go with the placebo effect than argue. I think we’ve all done that before.
There are also a lot of nonneurologists in practice who still, after almost 30 years on the market, think Aricept improves memory, when in fact that’s far from the truth. The best it can claim to do is slow down the rate at which patients get worse, but nobody wants to hear that.
I’ve also seen Aricept used for pseudodementia due to depression. Actually, I’ve seen it used for depression, too. Sometimes it’s used to counteract the side effects dof drugs that can impair cognition, such as Topamax, even in patients who aren’t even remotely demented.
None of the above are a major issue on their own. Where the trouble really happens, as with so many other things, is when they collide with an EMR, or someone too rushed to take a history, or both.
Let’s say Mrs. Jones is on Aricept because she went into a room, then forgot why she did.
Then she gets admitted to the hospital for pneumonia. Or she changes doctors and, like many practices these days, her medications are put in the computer by an MA or secretary.
A lot of times , so that gets punched in as a diagnosis and the patient is now believed to be unable to provide a reliable history. Or the person entering the info looks up its indication and enters “Alzheimer’s disease.”
Even worse is that I’ve seen EMRs where, in an effort to save time, the computer automatically enters diagnoses as you type medications in, and it’s up to the doctor to review them for accuracy. How that saves time I have no idea. But, as above, in these cases it’s going to lead to an entry of dementia where there isn’t any.
That, in particular, is pretty scary. As I wrote here in January of this year, what happens in the EMR stays in the EMR (kind of like Las Vegas).
I’m not knocking off-label use of medications. I don’t know a doctor who doesn’t use some that way, including myself.
But when doing so leads to the wrong assumptions and diagnoses it creates a lot of problems.
Dr. Block has a solo neurology practice in Scottsdale, Ariz.
Study: Physical fitness in children linked with concentration, quality of life
The findings of the German study involving more than 6,500 kids emphasize the importance of cardiorespiratory health in childhood, and support physical fitness initiatives in schools, according to lead author Katharina Köble, MSc, of the Technical University of Munich (Germany), and colleagues.
“Recent studies show that only a few children meet the recommendations of physical activity,” the investigators wrote in Journal of Clinical Medicine.
While the health benefits of physical activity are clearly documented, Ms. Köble and colleagues noted that typical measures of activity, such as accelerometers or self-reported questionnaires, are suboptimal research tools.
“Physical fitness is a more objective parameter to quantify when evaluating health promotion,” the investigators wrote. “Furthermore, cardiorespiratory fitness as part of physical fitness is more strongly related to risk factors of cardiovascular disease than physical activity.”
According to the investigators, physical fitness has also been linked with better concentration and HRQOL, but never in the same population of children.
The new study aimed to address this knowledge gap by assessing 6,533 healthy children aged 6-10 years, approximately half boys and half girls. Associations between physical fitness, concentration, and HRQOL were evaluated using multiple linear regression analysis in participants aged 9-10 years.
Physical fitness was measured using a series of challenges, including curl-ups (pull-ups with palms facing body), push-ups, standing long jump, handgrip strength measurement, and Progressive Aerobic Cardiovascular Endurance Run (PACER). Performing the multistage shuttle run, PACER, “requires participants to maintain the pace set by an audio signal, which progressively increases the intensity every minute.” Results of the PACER test were used to estimate VO2max.
Concentration was measured using the d2-R test, “a paper-pencil cancellation test, where subjects have to cross out all ‘d’ letters with two dashes under a time limit.”
HRQOL was evaluated with the KINDL questionnaire, which covers emotional well-being, physical well-being, everyday functioning (school), friends, family, and self-esteem.
Analysis showed that physical fitness improved with age (P < .001), except for VO2max in girls (P = .129). Concentration also improved with age (P < .001), while HRQOL did not (P = .179).
Among children aged 9-10 years, VO2max scores were strongly associated with both HRQOL (P < .001) and concentration (P < .001).
“VO2max was found to be one of the main factors influencing concentration levels and HRQOL dimensions in primary school children,” the investigators wrote. “Physical fitness, especially cardiorespiratory performance, should therefore be promoted more specifically in school settings to support the promotion of an overall healthy lifestyle in children and adolescents.”
Findings are having a real-word impact, according to researcher
In an interview, Ms. Köble noted that the findings are already having a real-world impact.
“We continued data assessment in the long-term and specifically adapted prevention programs in school to the needs of the school children we identified in our study,” she said. “Schools are partially offering specific movement and nutrition classes now.”
In addition, Ms. Köble and colleagues plan on educating teachers about the “urgent need for sufficient physical activity.”
“Academic performance should be considered as an additional health factor in future studies, as well as screen time and eating patterns, as all those variables showed interactions with physical fitness and concentration. In a subanalysis, we showed that children with better physical fitness and concentration values were those who usually went to higher education secondary schools,” they wrote.
VO2max did not correlate with BMI
Gregory Weaver, MD, a pediatrician at Cleveland Clinic Children’s, voiced some concerns about the reliability of the findings. He noted that VO2max did not correlate with body mass index or other measures of physical fitness, and that using the PACER test to estimate VO2max may have skewed the association between physical fitness and concentration.
“It is quite conceivable that children who can maintain the focus to perform maximally on this test will also do well on other tests of attention/concentration,” Dr. Weaver said. “Most children I know would have a very difficult time performing a physical fitness test which requires them to match a recorded pace that slowly increases overtime. I’m not an expert in the area, but it is my understanding that usually VO2max tests involve a treadmill which allows investigators to have complete control over pace.”
Dr. Weaver concluded that more work is needed to determine if physical fitness interventions can have a positive impact on HRQOL and concentration.
“I think the authors of this study attempted to ask an important question about the possible association between physical fitness and concentration among school aged children,” Dr. Weaver said in an interview. “But what is even more vital are studies demonstrating that a change in modifiable health factors like nutrition, physical fitness, or the built environment can improve quality of life. I was hoping the authors would show that an improvement in VO2max over time resulted in an improvement in concentration. Frustratingly, that is not what this article demonstrates.”
The investigators and Dr. Weaver reported no conflicts of interest.
The findings of the German study involving more than 6,500 kids emphasize the importance of cardiorespiratory health in childhood, and support physical fitness initiatives in schools, according to lead author Katharina Köble, MSc, of the Technical University of Munich (Germany), and colleagues.
“Recent studies show that only a few children meet the recommendations of physical activity,” the investigators wrote in Journal of Clinical Medicine.
While the health benefits of physical activity are clearly documented, Ms. Köble and colleagues noted that typical measures of activity, such as accelerometers or self-reported questionnaires, are suboptimal research tools.
“Physical fitness is a more objective parameter to quantify when evaluating health promotion,” the investigators wrote. “Furthermore, cardiorespiratory fitness as part of physical fitness is more strongly related to risk factors of cardiovascular disease than physical activity.”
According to the investigators, physical fitness has also been linked with better concentration and HRQOL, but never in the same population of children.
The new study aimed to address this knowledge gap by assessing 6,533 healthy children aged 6-10 years, approximately half boys and half girls. Associations between physical fitness, concentration, and HRQOL were evaluated using multiple linear regression analysis in participants aged 9-10 years.
Physical fitness was measured using a series of challenges, including curl-ups (pull-ups with palms facing body), push-ups, standing long jump, handgrip strength measurement, and Progressive Aerobic Cardiovascular Endurance Run (PACER). Performing the multistage shuttle run, PACER, “requires participants to maintain the pace set by an audio signal, which progressively increases the intensity every minute.” Results of the PACER test were used to estimate VO2max.
Concentration was measured using the d2-R test, “a paper-pencil cancellation test, where subjects have to cross out all ‘d’ letters with two dashes under a time limit.”
HRQOL was evaluated with the KINDL questionnaire, which covers emotional well-being, physical well-being, everyday functioning (school), friends, family, and self-esteem.
Analysis showed that physical fitness improved with age (P < .001), except for VO2max in girls (P = .129). Concentration also improved with age (P < .001), while HRQOL did not (P = .179).
Among children aged 9-10 years, VO2max scores were strongly associated with both HRQOL (P < .001) and concentration (P < .001).
“VO2max was found to be one of the main factors influencing concentration levels and HRQOL dimensions in primary school children,” the investigators wrote. “Physical fitness, especially cardiorespiratory performance, should therefore be promoted more specifically in school settings to support the promotion of an overall healthy lifestyle in children and adolescents.”
Findings are having a real-word impact, according to researcher
In an interview, Ms. Köble noted that the findings are already having a real-world impact.
“We continued data assessment in the long-term and specifically adapted prevention programs in school to the needs of the school children we identified in our study,” she said. “Schools are partially offering specific movement and nutrition classes now.”
In addition, Ms. Köble and colleagues plan on educating teachers about the “urgent need for sufficient physical activity.”
“Academic performance should be considered as an additional health factor in future studies, as well as screen time and eating patterns, as all those variables showed interactions with physical fitness and concentration. In a subanalysis, we showed that children with better physical fitness and concentration values were those who usually went to higher education secondary schools,” they wrote.
VO2max did not correlate with BMI
Gregory Weaver, MD, a pediatrician at Cleveland Clinic Children’s, voiced some concerns about the reliability of the findings. He noted that VO2max did not correlate with body mass index or other measures of physical fitness, and that using the PACER test to estimate VO2max may have skewed the association between physical fitness and concentration.
“It is quite conceivable that children who can maintain the focus to perform maximally on this test will also do well on other tests of attention/concentration,” Dr. Weaver said. “Most children I know would have a very difficult time performing a physical fitness test which requires them to match a recorded pace that slowly increases overtime. I’m not an expert in the area, but it is my understanding that usually VO2max tests involve a treadmill which allows investigators to have complete control over pace.”
Dr. Weaver concluded that more work is needed to determine if physical fitness interventions can have a positive impact on HRQOL and concentration.
“I think the authors of this study attempted to ask an important question about the possible association between physical fitness and concentration among school aged children,” Dr. Weaver said in an interview. “But what is even more vital are studies demonstrating that a change in modifiable health factors like nutrition, physical fitness, or the built environment can improve quality of life. I was hoping the authors would show that an improvement in VO2max over time resulted in an improvement in concentration. Frustratingly, that is not what this article demonstrates.”
The investigators and Dr. Weaver reported no conflicts of interest.
The findings of the German study involving more than 6,500 kids emphasize the importance of cardiorespiratory health in childhood, and support physical fitness initiatives in schools, according to lead author Katharina Köble, MSc, of the Technical University of Munich (Germany), and colleagues.
“Recent studies show that only a few children meet the recommendations of physical activity,” the investigators wrote in Journal of Clinical Medicine.
While the health benefits of physical activity are clearly documented, Ms. Köble and colleagues noted that typical measures of activity, such as accelerometers or self-reported questionnaires, are suboptimal research tools.
“Physical fitness is a more objective parameter to quantify when evaluating health promotion,” the investigators wrote. “Furthermore, cardiorespiratory fitness as part of physical fitness is more strongly related to risk factors of cardiovascular disease than physical activity.”
According to the investigators, physical fitness has also been linked with better concentration and HRQOL, but never in the same population of children.
The new study aimed to address this knowledge gap by assessing 6,533 healthy children aged 6-10 years, approximately half boys and half girls. Associations between physical fitness, concentration, and HRQOL were evaluated using multiple linear regression analysis in participants aged 9-10 years.
Physical fitness was measured using a series of challenges, including curl-ups (pull-ups with palms facing body), push-ups, standing long jump, handgrip strength measurement, and Progressive Aerobic Cardiovascular Endurance Run (PACER). Performing the multistage shuttle run, PACER, “requires participants to maintain the pace set by an audio signal, which progressively increases the intensity every minute.” Results of the PACER test were used to estimate VO2max.
Concentration was measured using the d2-R test, “a paper-pencil cancellation test, where subjects have to cross out all ‘d’ letters with two dashes under a time limit.”
HRQOL was evaluated with the KINDL questionnaire, which covers emotional well-being, physical well-being, everyday functioning (school), friends, family, and self-esteem.
Analysis showed that physical fitness improved with age (P < .001), except for VO2max in girls (P = .129). Concentration also improved with age (P < .001), while HRQOL did not (P = .179).
Among children aged 9-10 years, VO2max scores were strongly associated with both HRQOL (P < .001) and concentration (P < .001).
“VO2max was found to be one of the main factors influencing concentration levels and HRQOL dimensions in primary school children,” the investigators wrote. “Physical fitness, especially cardiorespiratory performance, should therefore be promoted more specifically in school settings to support the promotion of an overall healthy lifestyle in children and adolescents.”
Findings are having a real-word impact, according to researcher
In an interview, Ms. Köble noted that the findings are already having a real-world impact.
“We continued data assessment in the long-term and specifically adapted prevention programs in school to the needs of the school children we identified in our study,” she said. “Schools are partially offering specific movement and nutrition classes now.”
In addition, Ms. Köble and colleagues plan on educating teachers about the “urgent need for sufficient physical activity.”
“Academic performance should be considered as an additional health factor in future studies, as well as screen time and eating patterns, as all those variables showed interactions with physical fitness and concentration. In a subanalysis, we showed that children with better physical fitness and concentration values were those who usually went to higher education secondary schools,” they wrote.
VO2max did not correlate with BMI
Gregory Weaver, MD, a pediatrician at Cleveland Clinic Children’s, voiced some concerns about the reliability of the findings. He noted that VO2max did not correlate with body mass index or other measures of physical fitness, and that using the PACER test to estimate VO2max may have skewed the association between physical fitness and concentration.
“It is quite conceivable that children who can maintain the focus to perform maximally on this test will also do well on other tests of attention/concentration,” Dr. Weaver said. “Most children I know would have a very difficult time performing a physical fitness test which requires them to match a recorded pace that slowly increases overtime. I’m not an expert in the area, but it is my understanding that usually VO2max tests involve a treadmill which allows investigators to have complete control over pace.”
Dr. Weaver concluded that more work is needed to determine if physical fitness interventions can have a positive impact on HRQOL and concentration.
“I think the authors of this study attempted to ask an important question about the possible association between physical fitness and concentration among school aged children,” Dr. Weaver said in an interview. “But what is even more vital are studies demonstrating that a change in modifiable health factors like nutrition, physical fitness, or the built environment can improve quality of life. I was hoping the authors would show that an improvement in VO2max over time resulted in an improvement in concentration. Frustratingly, that is not what this article demonstrates.”
The investigators and Dr. Weaver reported no conflicts of interest.
FROM THE JOURNAL OF CLINICAL MEDICINE
Physical fitness tied to lower risk of Alzheimer’s disease
, new findings suggest. “One exciting finding of this study is that as people’s fitness improved, their risk of Alzheimer’s disease decreased – it was not an all-or-nothing proposition,” study investigator Edward Zamrini, MD, of the Washington DC VA Medical Center, said in a news release.
The findings suggest that people can work toward making incremental changes and improvements in their physical fitness, which may help decrease their risk of dementia, Dr. Zamrini added.
The findings were presented at the 2022 annual meeting of the American Academy of Neurology.
Effective prevention strategy
Using the Veterans Health Administration database, Dr. Zamrini and colleagues identified 649,605 veterans (mean age, 61 years) free of Alzheimer’s disease and related disorders (ADRD) when they completed standardized exercise treadmill tests between 2000 and 2017.
They divided participants into five age-specific fitness groups, from least fit to most fit, based on peak metabolic equivalents (METs) achieved during the treadmill test: lowest-fit (METs, ±3.8), low-fit (METs, ±5.8), moderate-fit (METs, ±7.5), fit (METs, ±9.2), and highest-fit (METs, ±11.7).
In unadjusted analysis, veterans with the lowest cardiorespiratory fitness developed ADRD at a rate of 9.5 cases per 1,000 person-years, compared with a rate of 6.4 cases per 1,000 person-years for the most fit group (P < .001).
After adjusting for factors that could affect risk of ADRD, compared with the lowest-fit group, the highest-fit and fit groups were 33% and 26% less likely to develop ADRD, respectively, while the moderate-fit and low-fit groups were 20% and 13% less likely to develop the disease, respectively.
The findings suggest that the association between cardiorespiratory fitness and ADRD risk is “inverse, independent, and graded,” the researchers said in their conference abstract.
“The idea that you can reduce your risk for Alzheimer’s disease by simply increasing your activity is very promising, especially since there are no adequate treatments to prevent or stop the progression of the disease,” Dr. Zamrini added in the news release.
“We hope to develop a simple scale that can be individualized so people can see the benefits that even incremental improvements in fitness can deliver,” he said.
The next vital sign?
Commenting on the study, Shaheen E. Lakhan, MD, PhD, a neurologist in Boston, noted that “for decades and with increasing body of support from studies like this, we have known that preventing dementia is based on healthy behaviors for the brain including a proper diet (NASH and/or Mediterranean), exercise regimen (aerobic/cardio more than anaerobic/weight-lifting), sleep hygiene, and social and intellectual engagements.”
“Frankly, what’s good for the body is good for the brain,” said Dr. Lakhan.
“It should be noted that the measure studied here is cardiorespiratory fitness, which has been associated with heart disease and resulting death, death from any cause, and now brain health,” Dr. Lakhan said.
“This powerful predictor may in fact be the next vital sign, after your heart rate and blood pressure, from which your primary care provider can make a personalized treatment plan,” he added.
“Accelerating this process, the ability to measure cardiorespiratory fitness traditionally from huge stationary machines down to wearables like a watch or ring, or even your iPhone or Android, is just on the horizon,” Dr. Lakhan said.
“Instead of tracking just your weight, shape, and BMI, personal fitness may be tailored to optimizing this indicator and further empowering individuals to take charge of their health,” he said.
The study was supported by the National Institute on Aging, the National Institutes of Health, the U.S. Department of Veterans Affairs, the Washington DC VA Medical Center, and George Washington University. Dr. Zamrini and Dr. Lakhan have disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.
, new findings suggest. “One exciting finding of this study is that as people’s fitness improved, their risk of Alzheimer’s disease decreased – it was not an all-or-nothing proposition,” study investigator Edward Zamrini, MD, of the Washington DC VA Medical Center, said in a news release.
The findings suggest that people can work toward making incremental changes and improvements in their physical fitness, which may help decrease their risk of dementia, Dr. Zamrini added.
The findings were presented at the 2022 annual meeting of the American Academy of Neurology.
Effective prevention strategy
Using the Veterans Health Administration database, Dr. Zamrini and colleagues identified 649,605 veterans (mean age, 61 years) free of Alzheimer’s disease and related disorders (ADRD) when they completed standardized exercise treadmill tests between 2000 and 2017.
They divided participants into five age-specific fitness groups, from least fit to most fit, based on peak metabolic equivalents (METs) achieved during the treadmill test: lowest-fit (METs, ±3.8), low-fit (METs, ±5.8), moderate-fit (METs, ±7.5), fit (METs, ±9.2), and highest-fit (METs, ±11.7).
In unadjusted analysis, veterans with the lowest cardiorespiratory fitness developed ADRD at a rate of 9.5 cases per 1,000 person-years, compared with a rate of 6.4 cases per 1,000 person-years for the most fit group (P < .001).
After adjusting for factors that could affect risk of ADRD, compared with the lowest-fit group, the highest-fit and fit groups were 33% and 26% less likely to develop ADRD, respectively, while the moderate-fit and low-fit groups were 20% and 13% less likely to develop the disease, respectively.
The findings suggest that the association between cardiorespiratory fitness and ADRD risk is “inverse, independent, and graded,” the researchers said in their conference abstract.
“The idea that you can reduce your risk for Alzheimer’s disease by simply increasing your activity is very promising, especially since there are no adequate treatments to prevent or stop the progression of the disease,” Dr. Zamrini added in the news release.
“We hope to develop a simple scale that can be individualized so people can see the benefits that even incremental improvements in fitness can deliver,” he said.
The next vital sign?
Commenting on the study, Shaheen E. Lakhan, MD, PhD, a neurologist in Boston, noted that “for decades and with increasing body of support from studies like this, we have known that preventing dementia is based on healthy behaviors for the brain including a proper diet (NASH and/or Mediterranean), exercise regimen (aerobic/cardio more than anaerobic/weight-lifting), sleep hygiene, and social and intellectual engagements.”
“Frankly, what’s good for the body is good for the brain,” said Dr. Lakhan.
“It should be noted that the measure studied here is cardiorespiratory fitness, which has been associated with heart disease and resulting death, death from any cause, and now brain health,” Dr. Lakhan said.
“This powerful predictor may in fact be the next vital sign, after your heart rate and blood pressure, from which your primary care provider can make a personalized treatment plan,” he added.
“Accelerating this process, the ability to measure cardiorespiratory fitness traditionally from huge stationary machines down to wearables like a watch or ring, or even your iPhone or Android, is just on the horizon,” Dr. Lakhan said.
“Instead of tracking just your weight, shape, and BMI, personal fitness may be tailored to optimizing this indicator and further empowering individuals to take charge of their health,” he said.
The study was supported by the National Institute on Aging, the National Institutes of Health, the U.S. Department of Veterans Affairs, the Washington DC VA Medical Center, and George Washington University. Dr. Zamrini and Dr. Lakhan have disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.
, new findings suggest. “One exciting finding of this study is that as people’s fitness improved, their risk of Alzheimer’s disease decreased – it was not an all-or-nothing proposition,” study investigator Edward Zamrini, MD, of the Washington DC VA Medical Center, said in a news release.
The findings suggest that people can work toward making incremental changes and improvements in their physical fitness, which may help decrease their risk of dementia, Dr. Zamrini added.
The findings were presented at the 2022 annual meeting of the American Academy of Neurology.
Effective prevention strategy
Using the Veterans Health Administration database, Dr. Zamrini and colleagues identified 649,605 veterans (mean age, 61 years) free of Alzheimer’s disease and related disorders (ADRD) when they completed standardized exercise treadmill tests between 2000 and 2017.
They divided participants into five age-specific fitness groups, from least fit to most fit, based on peak metabolic equivalents (METs) achieved during the treadmill test: lowest-fit (METs, ±3.8), low-fit (METs, ±5.8), moderate-fit (METs, ±7.5), fit (METs, ±9.2), and highest-fit (METs, ±11.7).
In unadjusted analysis, veterans with the lowest cardiorespiratory fitness developed ADRD at a rate of 9.5 cases per 1,000 person-years, compared with a rate of 6.4 cases per 1,000 person-years for the most fit group (P < .001).
After adjusting for factors that could affect risk of ADRD, compared with the lowest-fit group, the highest-fit and fit groups were 33% and 26% less likely to develop ADRD, respectively, while the moderate-fit and low-fit groups were 20% and 13% less likely to develop the disease, respectively.
The findings suggest that the association between cardiorespiratory fitness and ADRD risk is “inverse, independent, and graded,” the researchers said in their conference abstract.
“The idea that you can reduce your risk for Alzheimer’s disease by simply increasing your activity is very promising, especially since there are no adequate treatments to prevent or stop the progression of the disease,” Dr. Zamrini added in the news release.
“We hope to develop a simple scale that can be individualized so people can see the benefits that even incremental improvements in fitness can deliver,” he said.
The next vital sign?
Commenting on the study, Shaheen E. Lakhan, MD, PhD, a neurologist in Boston, noted that “for decades and with increasing body of support from studies like this, we have known that preventing dementia is based on healthy behaviors for the brain including a proper diet (NASH and/or Mediterranean), exercise regimen (aerobic/cardio more than anaerobic/weight-lifting), sleep hygiene, and social and intellectual engagements.”
“Frankly, what’s good for the body is good for the brain,” said Dr. Lakhan.
“It should be noted that the measure studied here is cardiorespiratory fitness, which has been associated with heart disease and resulting death, death from any cause, and now brain health,” Dr. Lakhan said.
“This powerful predictor may in fact be the next vital sign, after your heart rate and blood pressure, from which your primary care provider can make a personalized treatment plan,” he added.
“Accelerating this process, the ability to measure cardiorespiratory fitness traditionally from huge stationary machines down to wearables like a watch or ring, or even your iPhone or Android, is just on the horizon,” Dr. Lakhan said.
“Instead of tracking just your weight, shape, and BMI, personal fitness may be tailored to optimizing this indicator and further empowering individuals to take charge of their health,” he said.
The study was supported by the National Institute on Aging, the National Institutes of Health, the U.S. Department of Veterans Affairs, the Washington DC VA Medical Center, and George Washington University. Dr. Zamrini and Dr. Lakhan have disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.
FROM AAN 2022
Some reproductive factors linked with risk of dementia
Certain reproductive factors are associated with greater or lower risk of dementia, according to researchers who conducted a large population-based study with UK Biobank data.
Jessica Gong, a PhD candidate at the George Institute for Global Health at University of New South Wales in Australia, and coauthors found a greater dementia risk in women with early and late menarche, women who were younger when they first gave birth, and those who had had a hysterectomy, especially those who had a hysterectomy without concomitant oophorectomy or with a previous oophorectomy.
After controlling for key confounders, the researchers found lower risk of all-cause dementia if women had ever been pregnant, ever had an abortion, had a longer reproductive span, or had later menopause.
Use of oral contraceptive pills was associated with a lower dementia risk, they found.
In this study, there was no evidence that hormone therapy (HT) was associated with dementia risk (hazard ratio, 0.99, 95% confidence interval [0.90-1.09], P =.0828).
The analysis, published online April 5 in PLOS Medicine, comprised 273,240 women and 228,957 men without prevalent dementia.
The authors noted that dementia rates are increasing. Globally, 50 million people live with dementia, and the number is expected to triple by 2050, according to Alzheimer’s Disease International.
“Our study identified certain reproductive factors related to shorter exposure to endogenous estrogen were associated with increased risk of dementia, highlighting the susceptibility in dementia risk pertaining to women,” Ms. Gong told this publication.
Risk comparison of men and women
Men were included in this study to compare the association between number of children fathered and the risk of all-cause dementia, with the association in their female counterparts.
The U-shaped associations between the number of children and dementia risk were similar for both sexes, suggesting that the risk difference in women may not be associated with factors associated with childbearing
“It may be more related to social and behavioral factors in parenthood, rather than biological factors involved in childbearing,” Ms. Gong said.
Compared with those with two children, for those without children, the multiple adjusted HR (95% CI) was 1.18 (1.04, 1.33) (P = .027) for women and 1.10 (0.98-1.23) P = .164) for men.
For those with four or more children, the HR was 1.14 (0.98, 1.33) (P = .132) for women and 1.26 (1.10-1.45) (P = .003) for men.
Rachel Buckley, PhD, assistant professor of neurology with a dual appointment at Brigham and Women’s and Massachusetts General hospitals in Boston, told this publication she found the comparison of dementia risk with number of children in men and women “fascinating.”
She said the argument usually is that if women have had more births, then they have had more estrogen through their body because women get a huge injection of hormones in pregnancy.
“The idea is that the more pregnancies you have the more protected you are. But this study put that on its head, because if men and women are showing increased [dementia] risk in the number of children they have, it suggests there must be something about having the children – not necessarily the circulating hormones – that might be having an impact,” Dr. Buckley said.
“I had never thought to compare the number of children in men. I do find that very interesting,” she said.
As for the lack of a link between HT and dementia risk, in this study she said, she wouldn’t shut the door on that discussion just yet.
She noted the long history of controversy in the field about whether there is a protective factor against dementia for estrogen or whether exposure to estrogen leads to increased risk.
Before the landmark Women’s Health Initiative (WHI) study in the 1990s, she pointed out, there was evidence in many observational studies that women who had longer exposure to estrogen – whether that was earlier age at first period and later age at menopause combined or women had taken hormone therapy at some point, had less risk for dementia.
Dr. Buckley said that in a secondary outcome of WHI, however, “there was increased risk for progression to dementia in women who were taking hormone therapy which essentially flipped the field on its ahead because until that point everybody thought that estrogen was a protective factor.”
She said although this study found no association with dementia, she still thinks HT has a role to play and that it may just need to be better tailored to individuals.
“If you think about it, we have our tailored cocktail of hormones in our body and who’s to say that my hormones are going to be the same as yours? Why should you and I be put on the same hormone therapy and assume that will give us the same outcome? I think we could do a lot better with customization and calibration of hormones to aid in women’s health.”
Lifetime approach to dementia
Ms. Gong says future dementia risk-reduction strategies should consider sex-specific risk, and consider the reproductive events that took place in women’s lifespans as well as their entire hormone history when assessing dementia risk, to ensure that the strategies are sex sensitive.
Dr. Buckley agrees: “I don’t think we should ever think about dementia in terms of 65 onwards. We know this disease is insidious and it starts very, very early.”
Regarding limitations, the authors noted that it was a retrospective study that included self-reported measures of reproductive factors, which may be inherently subject to recall bias.
A coauthor does consultant work for Amgen, Freeline, and Kirin outside the submitted work. There were no other relevant financial disclosures.
Certain reproductive factors are associated with greater or lower risk of dementia, according to researchers who conducted a large population-based study with UK Biobank data.
Jessica Gong, a PhD candidate at the George Institute for Global Health at University of New South Wales in Australia, and coauthors found a greater dementia risk in women with early and late menarche, women who were younger when they first gave birth, and those who had had a hysterectomy, especially those who had a hysterectomy without concomitant oophorectomy or with a previous oophorectomy.
After controlling for key confounders, the researchers found lower risk of all-cause dementia if women had ever been pregnant, ever had an abortion, had a longer reproductive span, or had later menopause.
Use of oral contraceptive pills was associated with a lower dementia risk, they found.
In this study, there was no evidence that hormone therapy (HT) was associated with dementia risk (hazard ratio, 0.99, 95% confidence interval [0.90-1.09], P =.0828).
The analysis, published online April 5 in PLOS Medicine, comprised 273,240 women and 228,957 men without prevalent dementia.
The authors noted that dementia rates are increasing. Globally, 50 million people live with dementia, and the number is expected to triple by 2050, according to Alzheimer’s Disease International.
“Our study identified certain reproductive factors related to shorter exposure to endogenous estrogen were associated with increased risk of dementia, highlighting the susceptibility in dementia risk pertaining to women,” Ms. Gong told this publication.
Risk comparison of men and women
Men were included in this study to compare the association between number of children fathered and the risk of all-cause dementia, with the association in their female counterparts.
The U-shaped associations between the number of children and dementia risk were similar for both sexes, suggesting that the risk difference in women may not be associated with factors associated with childbearing
“It may be more related to social and behavioral factors in parenthood, rather than biological factors involved in childbearing,” Ms. Gong said.
Compared with those with two children, for those without children, the multiple adjusted HR (95% CI) was 1.18 (1.04, 1.33) (P = .027) for women and 1.10 (0.98-1.23) P = .164) for men.
For those with four or more children, the HR was 1.14 (0.98, 1.33) (P = .132) for women and 1.26 (1.10-1.45) (P = .003) for men.
Rachel Buckley, PhD, assistant professor of neurology with a dual appointment at Brigham and Women’s and Massachusetts General hospitals in Boston, told this publication she found the comparison of dementia risk with number of children in men and women “fascinating.”
She said the argument usually is that if women have had more births, then they have had more estrogen through their body because women get a huge injection of hormones in pregnancy.
“The idea is that the more pregnancies you have the more protected you are. But this study put that on its head, because if men and women are showing increased [dementia] risk in the number of children they have, it suggests there must be something about having the children – not necessarily the circulating hormones – that might be having an impact,” Dr. Buckley said.
“I had never thought to compare the number of children in men. I do find that very interesting,” she said.
As for the lack of a link between HT and dementia risk, in this study she said, she wouldn’t shut the door on that discussion just yet.
She noted the long history of controversy in the field about whether there is a protective factor against dementia for estrogen or whether exposure to estrogen leads to increased risk.
Before the landmark Women’s Health Initiative (WHI) study in the 1990s, she pointed out, there was evidence in many observational studies that women who had longer exposure to estrogen – whether that was earlier age at first period and later age at menopause combined or women had taken hormone therapy at some point, had less risk for dementia.
Dr. Buckley said that in a secondary outcome of WHI, however, “there was increased risk for progression to dementia in women who were taking hormone therapy which essentially flipped the field on its ahead because until that point everybody thought that estrogen was a protective factor.”
She said although this study found no association with dementia, she still thinks HT has a role to play and that it may just need to be better tailored to individuals.
“If you think about it, we have our tailored cocktail of hormones in our body and who’s to say that my hormones are going to be the same as yours? Why should you and I be put on the same hormone therapy and assume that will give us the same outcome? I think we could do a lot better with customization and calibration of hormones to aid in women’s health.”
Lifetime approach to dementia
Ms. Gong says future dementia risk-reduction strategies should consider sex-specific risk, and consider the reproductive events that took place in women’s lifespans as well as their entire hormone history when assessing dementia risk, to ensure that the strategies are sex sensitive.
Dr. Buckley agrees: “I don’t think we should ever think about dementia in terms of 65 onwards. We know this disease is insidious and it starts very, very early.”
Regarding limitations, the authors noted that it was a retrospective study that included self-reported measures of reproductive factors, which may be inherently subject to recall bias.
A coauthor does consultant work for Amgen, Freeline, and Kirin outside the submitted work. There were no other relevant financial disclosures.
Certain reproductive factors are associated with greater or lower risk of dementia, according to researchers who conducted a large population-based study with UK Biobank data.
Jessica Gong, a PhD candidate at the George Institute for Global Health at University of New South Wales in Australia, and coauthors found a greater dementia risk in women with early and late menarche, women who were younger when they first gave birth, and those who had had a hysterectomy, especially those who had a hysterectomy without concomitant oophorectomy or with a previous oophorectomy.
After controlling for key confounders, the researchers found lower risk of all-cause dementia if women had ever been pregnant, ever had an abortion, had a longer reproductive span, or had later menopause.
Use of oral contraceptive pills was associated with a lower dementia risk, they found.
In this study, there was no evidence that hormone therapy (HT) was associated with dementia risk (hazard ratio, 0.99, 95% confidence interval [0.90-1.09], P =.0828).
The analysis, published online April 5 in PLOS Medicine, comprised 273,240 women and 228,957 men without prevalent dementia.
The authors noted that dementia rates are increasing. Globally, 50 million people live with dementia, and the number is expected to triple by 2050, according to Alzheimer’s Disease International.
“Our study identified certain reproductive factors related to shorter exposure to endogenous estrogen were associated with increased risk of dementia, highlighting the susceptibility in dementia risk pertaining to women,” Ms. Gong told this publication.
Risk comparison of men and women
Men were included in this study to compare the association between number of children fathered and the risk of all-cause dementia, with the association in their female counterparts.
The U-shaped associations between the number of children and dementia risk were similar for both sexes, suggesting that the risk difference in women may not be associated with factors associated with childbearing
“It may be more related to social and behavioral factors in parenthood, rather than biological factors involved in childbearing,” Ms. Gong said.
Compared with those with two children, for those without children, the multiple adjusted HR (95% CI) was 1.18 (1.04, 1.33) (P = .027) for women and 1.10 (0.98-1.23) P = .164) for men.
For those with four or more children, the HR was 1.14 (0.98, 1.33) (P = .132) for women and 1.26 (1.10-1.45) (P = .003) for men.
Rachel Buckley, PhD, assistant professor of neurology with a dual appointment at Brigham and Women’s and Massachusetts General hospitals in Boston, told this publication she found the comparison of dementia risk with number of children in men and women “fascinating.”
She said the argument usually is that if women have had more births, then they have had more estrogen through their body because women get a huge injection of hormones in pregnancy.
“The idea is that the more pregnancies you have the more protected you are. But this study put that on its head, because if men and women are showing increased [dementia] risk in the number of children they have, it suggests there must be something about having the children – not necessarily the circulating hormones – that might be having an impact,” Dr. Buckley said.
“I had never thought to compare the number of children in men. I do find that very interesting,” she said.
As for the lack of a link between HT and dementia risk, in this study she said, she wouldn’t shut the door on that discussion just yet.
She noted the long history of controversy in the field about whether there is a protective factor against dementia for estrogen or whether exposure to estrogen leads to increased risk.
Before the landmark Women’s Health Initiative (WHI) study in the 1990s, she pointed out, there was evidence in many observational studies that women who had longer exposure to estrogen – whether that was earlier age at first period and later age at menopause combined or women had taken hormone therapy at some point, had less risk for dementia.
Dr. Buckley said that in a secondary outcome of WHI, however, “there was increased risk for progression to dementia in women who were taking hormone therapy which essentially flipped the field on its ahead because until that point everybody thought that estrogen was a protective factor.”
She said although this study found no association with dementia, she still thinks HT has a role to play and that it may just need to be better tailored to individuals.
“If you think about it, we have our tailored cocktail of hormones in our body and who’s to say that my hormones are going to be the same as yours? Why should you and I be put on the same hormone therapy and assume that will give us the same outcome? I think we could do a lot better with customization and calibration of hormones to aid in women’s health.”
Lifetime approach to dementia
Ms. Gong says future dementia risk-reduction strategies should consider sex-specific risk, and consider the reproductive events that took place in women’s lifespans as well as their entire hormone history when assessing dementia risk, to ensure that the strategies are sex sensitive.
Dr. Buckley agrees: “I don’t think we should ever think about dementia in terms of 65 onwards. We know this disease is insidious and it starts very, very early.”
Regarding limitations, the authors noted that it was a retrospective study that included self-reported measures of reproductive factors, which may be inherently subject to recall bias.
A coauthor does consultant work for Amgen, Freeline, and Kirin outside the submitted work. There were no other relevant financial disclosures.
FROM PLOS MEDICINE
Experimental drug may boost executive function in patients with Alzheimer’s disease
Patients performed better in cognitive testing after just 2 weeks, especially in areas of executive functioning. Clinicians involved in the study also reported improvements in patients’ ability to complete daily activities, especially in complex tasks such as using a computer, carrying out household chores, and managing their medications.
“It’s pretty incredible to see improvement over the course of a week to a week and a half,” said study investigator Aaron Koenig, MD, vice president of Early Clinical Development at Sage Therapeutics in Cambridge, Mass. “Not only are we seeing objective improvement, we’re also seeing a subjective benefit.”
The drug, SAGE-718, is also under study for MCI in patients with Huntington’s disease, the drug’s primary indication, and Parkinson’s disease.
The findings will be presented at the 2022 annual meeting of the American Academy of Neurology.
Improved executive function
SAGE-718 is in a new class of drugs called positive allosteric modulator of N-methyl-D-aspartate (NMDA) receptors, which are thought to improve neuroplasticity.
For the phase 2a open-label LUMINARY trial, researchers enrolled 26 patients ages 50-80 years with Alzheimer’s disease who had MCI. Patients completed a battery of cognitive tests at the study outset, again at the end of treatment, and again after 28 days.
Participants received SAGE-718 daily for 2 weeks and were followed for another 2 weeks.
The study’s primary outcome was safety. Seven patients (26.9%) reported mild or moderate treatment-emergent adverse events (AEs), and there were no serious AEs or deaths.
However, after 14 days, researchers also noted improvements from baseline on multiple tests of executive functioning, learning, and memory. And at 28 days, participants demonstrated significantly better Montreal Cognitive Assessment scores, compared with baseline (+2.3 points; P < .05), suggesting improvement in global cognition.
“We know that in Alzheimer’s and other neurodegenerative conditions there is a change in cognition, the ability to think, the ability to do things,” Dr. Koenig said. “What we’ve seen with SAGE-718 to date, all the way back to our phase 1 studies, is a cognitively beneficial effect, but more specifically an improvement in executive functioning.”
Intentional small study design
Commenting on the findings, Percy Griffin, PhD, MSc, director of scientific engagement for the Alzheimer’s Association, said that because of the small study size, short follow-up, and limited data available in the conference abstract, “we cannot speculate about the efficacy of this investigational therapy.”
“Bigger picture, the real-world clinical meaningfulness of research results that are generated in highly controlled circumstances is an important question that is being discussed right now throughout the Alzheimer’s field,” he added.
However, Dr. Koenig countered that the small study design was intentional. “Over the course of a year, we can get to the answer in different patient populations rather than running these rather large and arduous trials that may pan out to not be positive,” he said.
“The purpose here is to say, directionally, are we seeing improvement that warrants further investigation? If you don’t see an effect in a small number of patients, if you don’t see that effect rather quickly, and if you don’t see an effect that should translate into something meaningful, we at SAGE believe that you may not have a drug there,” he added.
Sage Therapeutics plans to launch a phase 2b placebo-controlled trial later this year to study SAGE-718 in more Alzheimer’s patients over a longer period of time.
The study was funded by SAGE Therapeutics. Dr. Koenig is an employee of SAGE and reports no other conflicts. Dr. Griffin has disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.
Patients performed better in cognitive testing after just 2 weeks, especially in areas of executive functioning. Clinicians involved in the study also reported improvements in patients’ ability to complete daily activities, especially in complex tasks such as using a computer, carrying out household chores, and managing their medications.
“It’s pretty incredible to see improvement over the course of a week to a week and a half,” said study investigator Aaron Koenig, MD, vice president of Early Clinical Development at Sage Therapeutics in Cambridge, Mass. “Not only are we seeing objective improvement, we’re also seeing a subjective benefit.”
The drug, SAGE-718, is also under study for MCI in patients with Huntington’s disease, the drug’s primary indication, and Parkinson’s disease.
The findings will be presented at the 2022 annual meeting of the American Academy of Neurology.
Improved executive function
SAGE-718 is in a new class of drugs called positive allosteric modulator of N-methyl-D-aspartate (NMDA) receptors, which are thought to improve neuroplasticity.
For the phase 2a open-label LUMINARY trial, researchers enrolled 26 patients ages 50-80 years with Alzheimer’s disease who had MCI. Patients completed a battery of cognitive tests at the study outset, again at the end of treatment, and again after 28 days.
Participants received SAGE-718 daily for 2 weeks and were followed for another 2 weeks.
The study’s primary outcome was safety. Seven patients (26.9%) reported mild or moderate treatment-emergent adverse events (AEs), and there were no serious AEs or deaths.
However, after 14 days, researchers also noted improvements from baseline on multiple tests of executive functioning, learning, and memory. And at 28 days, participants demonstrated significantly better Montreal Cognitive Assessment scores, compared with baseline (+2.3 points; P < .05), suggesting improvement in global cognition.
“We know that in Alzheimer’s and other neurodegenerative conditions there is a change in cognition, the ability to think, the ability to do things,” Dr. Koenig said. “What we’ve seen with SAGE-718 to date, all the way back to our phase 1 studies, is a cognitively beneficial effect, but more specifically an improvement in executive functioning.”
Intentional small study design
Commenting on the findings, Percy Griffin, PhD, MSc, director of scientific engagement for the Alzheimer’s Association, said that because of the small study size, short follow-up, and limited data available in the conference abstract, “we cannot speculate about the efficacy of this investigational therapy.”
“Bigger picture, the real-world clinical meaningfulness of research results that are generated in highly controlled circumstances is an important question that is being discussed right now throughout the Alzheimer’s field,” he added.
However, Dr. Koenig countered that the small study design was intentional. “Over the course of a year, we can get to the answer in different patient populations rather than running these rather large and arduous trials that may pan out to not be positive,” he said.
“The purpose here is to say, directionally, are we seeing improvement that warrants further investigation? If you don’t see an effect in a small number of patients, if you don’t see that effect rather quickly, and if you don’t see an effect that should translate into something meaningful, we at SAGE believe that you may not have a drug there,” he added.
Sage Therapeutics plans to launch a phase 2b placebo-controlled trial later this year to study SAGE-718 in more Alzheimer’s patients over a longer period of time.
The study was funded by SAGE Therapeutics. Dr. Koenig is an employee of SAGE and reports no other conflicts. Dr. Griffin has disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.
Patients performed better in cognitive testing after just 2 weeks, especially in areas of executive functioning. Clinicians involved in the study also reported improvements in patients’ ability to complete daily activities, especially in complex tasks such as using a computer, carrying out household chores, and managing their medications.
“It’s pretty incredible to see improvement over the course of a week to a week and a half,” said study investigator Aaron Koenig, MD, vice president of Early Clinical Development at Sage Therapeutics in Cambridge, Mass. “Not only are we seeing objective improvement, we’re also seeing a subjective benefit.”
The drug, SAGE-718, is also under study for MCI in patients with Huntington’s disease, the drug’s primary indication, and Parkinson’s disease.
The findings will be presented at the 2022 annual meeting of the American Academy of Neurology.
Improved executive function
SAGE-718 is in a new class of drugs called positive allosteric modulator of N-methyl-D-aspartate (NMDA) receptors, which are thought to improve neuroplasticity.
For the phase 2a open-label LUMINARY trial, researchers enrolled 26 patients ages 50-80 years with Alzheimer’s disease who had MCI. Patients completed a battery of cognitive tests at the study outset, again at the end of treatment, and again after 28 days.
Participants received SAGE-718 daily for 2 weeks and were followed for another 2 weeks.
The study’s primary outcome was safety. Seven patients (26.9%) reported mild or moderate treatment-emergent adverse events (AEs), and there were no serious AEs or deaths.
However, after 14 days, researchers also noted improvements from baseline on multiple tests of executive functioning, learning, and memory. And at 28 days, participants demonstrated significantly better Montreal Cognitive Assessment scores, compared with baseline (+2.3 points; P < .05), suggesting improvement in global cognition.
“We know that in Alzheimer’s and other neurodegenerative conditions there is a change in cognition, the ability to think, the ability to do things,” Dr. Koenig said. “What we’ve seen with SAGE-718 to date, all the way back to our phase 1 studies, is a cognitively beneficial effect, but more specifically an improvement in executive functioning.”
Intentional small study design
Commenting on the findings, Percy Griffin, PhD, MSc, director of scientific engagement for the Alzheimer’s Association, said that because of the small study size, short follow-up, and limited data available in the conference abstract, “we cannot speculate about the efficacy of this investigational therapy.”
“Bigger picture, the real-world clinical meaningfulness of research results that are generated in highly controlled circumstances is an important question that is being discussed right now throughout the Alzheimer’s field,” he added.
However, Dr. Koenig countered that the small study design was intentional. “Over the course of a year, we can get to the answer in different patient populations rather than running these rather large and arduous trials that may pan out to not be positive,” he said.
“The purpose here is to say, directionally, are we seeing improvement that warrants further investigation? If you don’t see an effect in a small number of patients, if you don’t see that effect rather quickly, and if you don’t see an effect that should translate into something meaningful, we at SAGE believe that you may not have a drug there,” he added.
Sage Therapeutics plans to launch a phase 2b placebo-controlled trial later this year to study SAGE-718 in more Alzheimer’s patients over a longer period of time.
The study was funded by SAGE Therapeutics. Dr. Koenig is an employee of SAGE and reports no other conflicts. Dr. Griffin has disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.
FROM AAN 2022
More evidence that COVID ‘brain fog’ is biologically based
Researchers found elevated levels of CSF immune activation and immunovascular markers in individuals with cognitive postacute sequelae of SARS-CoV-2 infection (PASC). Patients whose cognitive symptoms developed during the acute phase of COVID-19 had the highest levels of brain inflammation.
The findings add to a growing body of evidence that suggests the condition often referred to as “brain fog” has a neurologic basis, said lead author Joanna Hellmuth, MD, MHS, assistant professor of neurology at the University of California, San Francisco Weill Institute of Neurosciences and the UCSF Memory and Aging Center.
The findings will be presented at the 2022 annual meeting of the American Academy of Neurology.
Inflammatory response
There are no effective diagnostic tests or treatments for cognitive PASC, which prompted the investigators to study inflammation in patients with the condition. Initial findings were reported earlier in 2022, which showed abnormalities in the CSF in 77% of patients with cognitive impairment. Patients without cognitive impairments had normal CSF.
Extending that work in this new study, researchers studied patients from the Long-term Impact of Infection With Novel Coronavirus (LIINC) study with confirmed SARS-CoV-2 infection who were not hospitalized. They conducted 2-hour neurocognitive interviews and identified 23 people with new, persistent cognitive symptoms (cognitive PASC) and 10 with no cognitive symptoms who served as controls.
All participants underwent additional neurologic examination and neuropsychological testing, and half agreed to a lumbar puncture to allow researchers to collect CSF samples. The CSF was collected a median of 10.2 months after initial COVID symptoms began.
Participants with cognitive PASC had higher median levels of CSF acute phase reactants C-reactive protein (0.007 mg/L vs. 0.000 mg/L; P =.004) and serum amyloid A (0.001 mg/L vs. 0.000 mg/L; P = .001), compared with COVID controls.
The PASC group also had elevated levels of CSF immune activation markers interferon gamma–inducible protein (IP-10), interleukin-8, and immunovascular markers vascular endothelial growth factor-C and VEGFR-1, although the differences with the control group were not statistically significant.
The timing of the onset of cognitive problems was also associated with higher levels of immune activation and immunovascular markers. Patients with brain fog that developed during the acute phase of COVID-19 had higher levels of CSF VEGF-C, compared with patients whose cognitive symptoms developed more than a month after initial COVID symptoms (173 pg/mL vs. 99 pg/mL; P = .048) and COVID controls (79 pg/mL; P = .048).
Acute onset cognitive PASC participants had higher CSF levels of IP-10 (P = .030), IL-8 (P = .048), placental growth factor (P = .030) and intercellular adhesion molecule-1 (P = .045), compared with COVID controls.
Researchers believe these new findings could mean that intrathecal immune activation and endothelial activation/dysfunction may contribute to cognitive PASC and that the mechanisms involved may be different in patients with acute cognitive PASC versus those with delayed onset.
“Our data suggests that perhaps in these people with more acute cognitive changes they don’t have the return to homeostasis,” Dr. Hellmuth said, while patients with delayed onset cognitive PASC had levels more in line with COVID patients who had no cognitive issues.
Moving the needle forward
Commenting on the findings, William Schaffner, MD, professor of infectious diseases, Vanderbilt University Medical Center, Nashville, Tenn., said that, while the study doesn’t rule out a possible psychological basis for cognitive PASC, it adds more weight to the biological argument.
“When you have nonspecific symptoms for which specific tests are unavailable,” Dr. Schaffner explained, “there is a natural question that always comes up: Is this principally a biologically induced phenomenon or psychological? This moves the needle substantially in the direction of a biological phenomenon.”
Another important element to the study, Dr. Schaffner said, is that the patients involved had mild COVID.
“Not every patient with long COVID symptoms had been hospitalized with severe disease,” he said. “There are inflammatory phenomenon in various organ systems such that even if the inflammatory response in the lung was not severe enough to get you into the hospital, there were inflammatory responses in other organ systems that could persist once the acute infection resolved.”
Although the small size of the study is a limitation, Dr. Schaffner said that shouldn’t minimize the importance of these findings.
“That it’s small doesn’t diminish its value,” he said. “The next step forward might be to try to associate the markers more specifically with COVID. The more precise we can be, the more convincing the story will become.”
The study was funded by the National Institutes of Health. Dr. Hellmuth received grant support from the National Institutes of Health/National Institute of Mental Health supporting this work and personal fees for medical-legal consultation outside of the submitted work. Dr. Schaffner disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.
Researchers found elevated levels of CSF immune activation and immunovascular markers in individuals with cognitive postacute sequelae of SARS-CoV-2 infection (PASC). Patients whose cognitive symptoms developed during the acute phase of COVID-19 had the highest levels of brain inflammation.
The findings add to a growing body of evidence that suggests the condition often referred to as “brain fog” has a neurologic basis, said lead author Joanna Hellmuth, MD, MHS, assistant professor of neurology at the University of California, San Francisco Weill Institute of Neurosciences and the UCSF Memory and Aging Center.
The findings will be presented at the 2022 annual meeting of the American Academy of Neurology.
Inflammatory response
There are no effective diagnostic tests or treatments for cognitive PASC, which prompted the investigators to study inflammation in patients with the condition. Initial findings were reported earlier in 2022, which showed abnormalities in the CSF in 77% of patients with cognitive impairment. Patients without cognitive impairments had normal CSF.
Extending that work in this new study, researchers studied patients from the Long-term Impact of Infection With Novel Coronavirus (LIINC) study with confirmed SARS-CoV-2 infection who were not hospitalized. They conducted 2-hour neurocognitive interviews and identified 23 people with new, persistent cognitive symptoms (cognitive PASC) and 10 with no cognitive symptoms who served as controls.
All participants underwent additional neurologic examination and neuropsychological testing, and half agreed to a lumbar puncture to allow researchers to collect CSF samples. The CSF was collected a median of 10.2 months after initial COVID symptoms began.
Participants with cognitive PASC had higher median levels of CSF acute phase reactants C-reactive protein (0.007 mg/L vs. 0.000 mg/L; P =.004) and serum amyloid A (0.001 mg/L vs. 0.000 mg/L; P = .001), compared with COVID controls.
The PASC group also had elevated levels of CSF immune activation markers interferon gamma–inducible protein (IP-10), interleukin-8, and immunovascular markers vascular endothelial growth factor-C and VEGFR-1, although the differences with the control group were not statistically significant.
The timing of the onset of cognitive problems was also associated with higher levels of immune activation and immunovascular markers. Patients with brain fog that developed during the acute phase of COVID-19 had higher levels of CSF VEGF-C, compared with patients whose cognitive symptoms developed more than a month after initial COVID symptoms (173 pg/mL vs. 99 pg/mL; P = .048) and COVID controls (79 pg/mL; P = .048).
Acute onset cognitive PASC participants had higher CSF levels of IP-10 (P = .030), IL-8 (P = .048), placental growth factor (P = .030) and intercellular adhesion molecule-1 (P = .045), compared with COVID controls.
Researchers believe these new findings could mean that intrathecal immune activation and endothelial activation/dysfunction may contribute to cognitive PASC and that the mechanisms involved may be different in patients with acute cognitive PASC versus those with delayed onset.
“Our data suggests that perhaps in these people with more acute cognitive changes they don’t have the return to homeostasis,” Dr. Hellmuth said, while patients with delayed onset cognitive PASC had levels more in line with COVID patients who had no cognitive issues.
Moving the needle forward
Commenting on the findings, William Schaffner, MD, professor of infectious diseases, Vanderbilt University Medical Center, Nashville, Tenn., said that, while the study doesn’t rule out a possible psychological basis for cognitive PASC, it adds more weight to the biological argument.
“When you have nonspecific symptoms for which specific tests are unavailable,” Dr. Schaffner explained, “there is a natural question that always comes up: Is this principally a biologically induced phenomenon or psychological? This moves the needle substantially in the direction of a biological phenomenon.”
Another important element to the study, Dr. Schaffner said, is that the patients involved had mild COVID.
“Not every patient with long COVID symptoms had been hospitalized with severe disease,” he said. “There are inflammatory phenomenon in various organ systems such that even if the inflammatory response in the lung was not severe enough to get you into the hospital, there were inflammatory responses in other organ systems that could persist once the acute infection resolved.”
Although the small size of the study is a limitation, Dr. Schaffner said that shouldn’t minimize the importance of these findings.
“That it’s small doesn’t diminish its value,” he said. “The next step forward might be to try to associate the markers more specifically with COVID. The more precise we can be, the more convincing the story will become.”
The study was funded by the National Institutes of Health. Dr. Hellmuth received grant support from the National Institutes of Health/National Institute of Mental Health supporting this work and personal fees for medical-legal consultation outside of the submitted work. Dr. Schaffner disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.
Researchers found elevated levels of CSF immune activation and immunovascular markers in individuals with cognitive postacute sequelae of SARS-CoV-2 infection (PASC). Patients whose cognitive symptoms developed during the acute phase of COVID-19 had the highest levels of brain inflammation.
The findings add to a growing body of evidence that suggests the condition often referred to as “brain fog” has a neurologic basis, said lead author Joanna Hellmuth, MD, MHS, assistant professor of neurology at the University of California, San Francisco Weill Institute of Neurosciences and the UCSF Memory and Aging Center.
The findings will be presented at the 2022 annual meeting of the American Academy of Neurology.
Inflammatory response
There are no effective diagnostic tests or treatments for cognitive PASC, which prompted the investigators to study inflammation in patients with the condition. Initial findings were reported earlier in 2022, which showed abnormalities in the CSF in 77% of patients with cognitive impairment. Patients without cognitive impairments had normal CSF.
Extending that work in this new study, researchers studied patients from the Long-term Impact of Infection With Novel Coronavirus (LIINC) study with confirmed SARS-CoV-2 infection who were not hospitalized. They conducted 2-hour neurocognitive interviews and identified 23 people with new, persistent cognitive symptoms (cognitive PASC) and 10 with no cognitive symptoms who served as controls.
All participants underwent additional neurologic examination and neuropsychological testing, and half agreed to a lumbar puncture to allow researchers to collect CSF samples. The CSF was collected a median of 10.2 months after initial COVID symptoms began.
Participants with cognitive PASC had higher median levels of CSF acute phase reactants C-reactive protein (0.007 mg/L vs. 0.000 mg/L; P =.004) and serum amyloid A (0.001 mg/L vs. 0.000 mg/L; P = .001), compared with COVID controls.
The PASC group also had elevated levels of CSF immune activation markers interferon gamma–inducible protein (IP-10), interleukin-8, and immunovascular markers vascular endothelial growth factor-C and VEGFR-1, although the differences with the control group were not statistically significant.
The timing of the onset of cognitive problems was also associated with higher levels of immune activation and immunovascular markers. Patients with brain fog that developed during the acute phase of COVID-19 had higher levels of CSF VEGF-C, compared with patients whose cognitive symptoms developed more than a month after initial COVID symptoms (173 pg/mL vs. 99 pg/mL; P = .048) and COVID controls (79 pg/mL; P = .048).
Acute onset cognitive PASC participants had higher CSF levels of IP-10 (P = .030), IL-8 (P = .048), placental growth factor (P = .030) and intercellular adhesion molecule-1 (P = .045), compared with COVID controls.
Researchers believe these new findings could mean that intrathecal immune activation and endothelial activation/dysfunction may contribute to cognitive PASC and that the mechanisms involved may be different in patients with acute cognitive PASC versus those with delayed onset.
“Our data suggests that perhaps in these people with more acute cognitive changes they don’t have the return to homeostasis,” Dr. Hellmuth said, while patients with delayed onset cognitive PASC had levels more in line with COVID patients who had no cognitive issues.
Moving the needle forward
Commenting on the findings, William Schaffner, MD, professor of infectious diseases, Vanderbilt University Medical Center, Nashville, Tenn., said that, while the study doesn’t rule out a possible psychological basis for cognitive PASC, it adds more weight to the biological argument.
“When you have nonspecific symptoms for which specific tests are unavailable,” Dr. Schaffner explained, “there is a natural question that always comes up: Is this principally a biologically induced phenomenon or psychological? This moves the needle substantially in the direction of a biological phenomenon.”
Another important element to the study, Dr. Schaffner said, is that the patients involved had mild COVID.
“Not every patient with long COVID symptoms had been hospitalized with severe disease,” he said. “There are inflammatory phenomenon in various organ systems such that even if the inflammatory response in the lung was not severe enough to get you into the hospital, there were inflammatory responses in other organ systems that could persist once the acute infection resolved.”
Although the small size of the study is a limitation, Dr. Schaffner said that shouldn’t minimize the importance of these findings.
“That it’s small doesn’t diminish its value,” he said. “The next step forward might be to try to associate the markers more specifically with COVID. The more precise we can be, the more convincing the story will become.”
The study was funded by the National Institutes of Health. Dr. Hellmuth received grant support from the National Institutes of Health/National Institute of Mental Health supporting this work and personal fees for medical-legal consultation outside of the submitted work. Dr. Schaffner disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.
FROM AAN 2022
Does evidence support benefits of omega-3 fatty acids?
Dietary supplements that contain omega-3 fatty acids have been widely consumed for years. Researchers have been investigating the benefits of such preparations for cardiovascular, neurologic, and psychological conditions. A recently published study on omega-3 fatty acids and depression inspired neurologist Hans-Christoph Diener, MD, PhD, of the Institute for Epidemiology at the University Duisburg-Essen (Germany), to examine scientific publications concerning omega-3 fatty acids or fish-oil capsules in more detail.
Prevention of depression
Dr. Diener told the story of how he stumbled upon an interesting article in JAMA in December 2021. It was about a placebo-controlled study that investigated whether omega-3 fatty acids can prevent incident depression.
As the study authors reported, treatment with omega-3 preparations in adults aged 50 years or older without clinically relevant symptoms of depression at study initiation was associated with a small but statistically significant increase in the risk for depression or clinically relevant symptoms of depression. There was no difference in mood scale value, however, over a median follow-up of 5.3 years. According to the study authors, these results did not support the administration of omega-3 preparations for the prevention of depression.
This study was, as Dr. Diener said, somewhat negative, but it did arouse his interest in questions such as what biological effects omega-3 fatty acids have and what is known “about this topic with regard to neurology,” he said. When reviewing the literature, he noticed that there “were association studies, i.e., studies that describe that the intake of omega-3 fatty acids may possibly be associated with a lower risk of certain diseases.”
Beginning with the Inuit
It all started “with observations of the Inuit [population] in Greenland and Alaska after World War II, because it was remarked upon that these people ate a lot of fish and seal meat and had a very low incidence of cardiovascular diseases.” Over the years, a large number of association studies have been published, which may have encouraged the assumption that omega-3 fatty acids have positive health effects on various conditions, such as cardiovascular diseases, hyperlipidemia, type 2 diabetes, various malignancies, cognitive impairments, Alzheimer’s disease, depression and anxiety disorders, heart failure, slipped disks, ADHD, symptoms of menopause, rheumatoid arthritis, asthma, periodontitis, epilepsy, chemotherapy tolerance, premenstrual syndrome, and nonalcoholic fatty liver disease.
Dr. Diener believes that the problem is that these are association studies. But association does not mean that there is a causal relationship.
Disappointing study results
On the contrary, the results from the randomized placebo-controlled studies are truly frustrating, according to the neurologist. A meta-analysis of the use of omega-3 fatty acids in cardiovascular diseases included 86 studies with over 162,000 patients. According to Dr. Diener, it did not reveal any benefit for overall and cardiovascular mortality, nor any benefit for the reduction of myocardial infarction and stroke.
The results did indicate a trend, however, for reduced mortality in coronary heart disease. Even so, the number needed to treat for this was 334, which means that 334 people would have to take omega-3 fatty acids for years to prevent one fatal cardiac event.
Aside from this study, Dr. Diener found six studies on Alzheimer’s disease and three studies on dementia with patient populations between 600 and 800. In these studies, too, a positive effect of omega-3 fatty acids could not be identified. Then he discovered another 31 placebo-controlled studies of omega-3 fatty acids for the treatment or prevention of depression and anxiety disorder. Despite including 50,000 patients, these studies also did not show any positive effect.
“I see a significant discrepancy between the promotion of omega-3 fatty acids, whether it’s on television, in the ‘yellow’ [journalism] press, or in advertisements, and the actual scientific evidence,” said Dr. Diener. “At least from a neurological perspective, there is no evidence that omega-3 fatty acids have any benefit. This is true for strokes, dementia, Alzheimer’s disease, depression, and anxiety disorders.”
Potential adverse effects
Omega-3 fatty acids also have potentially adverse effects. The VITAL Rhythm study recently provided evidence that, depending on the dose, preparations with omega-3 fatty acids may increase the risk for atrial fibrillation. As the authors wrote, the results do not support taking omega-3 fatty acids to prevent atrial fibrillation.
In 2019, the global market for omega-3 fatty acids reached a value of $4.1 billion. This value is expected to double by 2025, according to a comment by Gregory Curfman, MD, deputy editor of JAMA and lecturer in health care policy at Harvard Medical School, Boston.
As Dr. Curfman wrote, this impressive amount of expenditure shows how beloved these products are and how strongly many people believe that omega-3 fatty acids are beneficial for their health. It is therefore important to know the potential risks of such preparations. One such example for this would be the risk for atrial fibrillation.
According to Dr. Curfman, in the last 2 years, four randomized clinical studies have provided data on the risk for atrial fibrillation associated with omega-3 fatty acids. In the STRENGTH study, 13,078 high-risk patients with cardiovascular diseases were randomly assigned to one of two groups. The subjects received either a high dose (4 g/day) of a combination of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) or corn oil. After a median of 42 months, there was no significant difference between the two groups in the primary composite cardiovascular endpoint, but more frequent atrial fibrillation in the omega-3 fatty acid group, compared with the corn oil group (2.2% vs. 1.3%; hazard ratio, 1.69; 95% confidence interval, 1.29-2.21; P < .001).
In the REDUCE-IT study, 8179 subjects were randomly assigned to a high dose (4 g/day, as in STRENGTH) of an omega-3 fatty acid preparation consisting of a purified EPA (icosapent ethyl) or mineral oil. After a median observation period of 4.9 years, icosapent ethyl was associated with a relative reduction of the primary composite cardiovascular endpoint by 25%, compared with mineral oil. As in the STRENGTH study, this study found that the risk for atrial fibrillation associated with omega-3 fatty acids, compared with mineral oil, was significantly higher (5.3% vs. 3.9%; P = .003).
In a third study (OMEMI), as Dr. Curfman reported, 1027 elderly patients who had recently had a myocardial infarction were randomly assigned to receive either a median dose of 1.8 g/day of omega-3 fatty acids (a combination of EPA and DHA) or corn oil. After 2 years, there was no significant difference between the two groups in primary composite cardiovascular endpoints, but 7.2% of the patients taking omega-3 fatty acids developed atrial fibrillation. In the corn oil group, this proportion was 4% (HR, 1.84; 95% CI, 0.98-3.45; P = .06).
The data from the four studies together indicate a potential dose-dependent risk for atrial fibrillation associated with omega-3 fatty acids, according to Dr. Curfman. At a dose of 4.0 g/day, there is a highly significant risk increase (almost double). With a median dose of 1.8 g/day, the risk increase (HR, 1.84) did not reach statistical significance. At a daily standard dose of 840 mg/day, an increase in risk could not be determined.
Dr. Curfman’s recommendation is that patients who take, or want to take, preparations with omega-3 fatty acids be informed of the potential development of arrhythmia at higher dosages. These patients also should undergo cardiological monitoring.
A version of this article first appeared on Medscape.com.
Dietary supplements that contain omega-3 fatty acids have been widely consumed for years. Researchers have been investigating the benefits of such preparations for cardiovascular, neurologic, and psychological conditions. A recently published study on omega-3 fatty acids and depression inspired neurologist Hans-Christoph Diener, MD, PhD, of the Institute for Epidemiology at the University Duisburg-Essen (Germany), to examine scientific publications concerning omega-3 fatty acids or fish-oil capsules in more detail.
Prevention of depression
Dr. Diener told the story of how he stumbled upon an interesting article in JAMA in December 2021. It was about a placebo-controlled study that investigated whether omega-3 fatty acids can prevent incident depression.
As the study authors reported, treatment with omega-3 preparations in adults aged 50 years or older without clinically relevant symptoms of depression at study initiation was associated with a small but statistically significant increase in the risk for depression or clinically relevant symptoms of depression. There was no difference in mood scale value, however, over a median follow-up of 5.3 years. According to the study authors, these results did not support the administration of omega-3 preparations for the prevention of depression.
This study was, as Dr. Diener said, somewhat negative, but it did arouse his interest in questions such as what biological effects omega-3 fatty acids have and what is known “about this topic with regard to neurology,” he said. When reviewing the literature, he noticed that there “were association studies, i.e., studies that describe that the intake of omega-3 fatty acids may possibly be associated with a lower risk of certain diseases.”
Beginning with the Inuit
It all started “with observations of the Inuit [population] in Greenland and Alaska after World War II, because it was remarked upon that these people ate a lot of fish and seal meat and had a very low incidence of cardiovascular diseases.” Over the years, a large number of association studies have been published, which may have encouraged the assumption that omega-3 fatty acids have positive health effects on various conditions, such as cardiovascular diseases, hyperlipidemia, type 2 diabetes, various malignancies, cognitive impairments, Alzheimer’s disease, depression and anxiety disorders, heart failure, slipped disks, ADHD, symptoms of menopause, rheumatoid arthritis, asthma, periodontitis, epilepsy, chemotherapy tolerance, premenstrual syndrome, and nonalcoholic fatty liver disease.
Dr. Diener believes that the problem is that these are association studies. But association does not mean that there is a causal relationship.
Disappointing study results
On the contrary, the results from the randomized placebo-controlled studies are truly frustrating, according to the neurologist. A meta-analysis of the use of omega-3 fatty acids in cardiovascular diseases included 86 studies with over 162,000 patients. According to Dr. Diener, it did not reveal any benefit for overall and cardiovascular mortality, nor any benefit for the reduction of myocardial infarction and stroke.
The results did indicate a trend, however, for reduced mortality in coronary heart disease. Even so, the number needed to treat for this was 334, which means that 334 people would have to take omega-3 fatty acids for years to prevent one fatal cardiac event.
Aside from this study, Dr. Diener found six studies on Alzheimer’s disease and three studies on dementia with patient populations between 600 and 800. In these studies, too, a positive effect of omega-3 fatty acids could not be identified. Then he discovered another 31 placebo-controlled studies of omega-3 fatty acids for the treatment or prevention of depression and anxiety disorder. Despite including 50,000 patients, these studies also did not show any positive effect.
“I see a significant discrepancy between the promotion of omega-3 fatty acids, whether it’s on television, in the ‘yellow’ [journalism] press, or in advertisements, and the actual scientific evidence,” said Dr. Diener. “At least from a neurological perspective, there is no evidence that omega-3 fatty acids have any benefit. This is true for strokes, dementia, Alzheimer’s disease, depression, and anxiety disorders.”
Potential adverse effects
Omega-3 fatty acids also have potentially adverse effects. The VITAL Rhythm study recently provided evidence that, depending on the dose, preparations with omega-3 fatty acids may increase the risk for atrial fibrillation. As the authors wrote, the results do not support taking omega-3 fatty acids to prevent atrial fibrillation.
In 2019, the global market for omega-3 fatty acids reached a value of $4.1 billion. This value is expected to double by 2025, according to a comment by Gregory Curfman, MD, deputy editor of JAMA and lecturer in health care policy at Harvard Medical School, Boston.
As Dr. Curfman wrote, this impressive amount of expenditure shows how beloved these products are and how strongly many people believe that omega-3 fatty acids are beneficial for their health. It is therefore important to know the potential risks of such preparations. One such example for this would be the risk for atrial fibrillation.
According to Dr. Curfman, in the last 2 years, four randomized clinical studies have provided data on the risk for atrial fibrillation associated with omega-3 fatty acids. In the STRENGTH study, 13,078 high-risk patients with cardiovascular diseases were randomly assigned to one of two groups. The subjects received either a high dose (4 g/day) of a combination of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) or corn oil. After a median of 42 months, there was no significant difference between the two groups in the primary composite cardiovascular endpoint, but more frequent atrial fibrillation in the omega-3 fatty acid group, compared with the corn oil group (2.2% vs. 1.3%; hazard ratio, 1.69; 95% confidence interval, 1.29-2.21; P < .001).
In the REDUCE-IT study, 8179 subjects were randomly assigned to a high dose (4 g/day, as in STRENGTH) of an omega-3 fatty acid preparation consisting of a purified EPA (icosapent ethyl) or mineral oil. After a median observation period of 4.9 years, icosapent ethyl was associated with a relative reduction of the primary composite cardiovascular endpoint by 25%, compared with mineral oil. As in the STRENGTH study, this study found that the risk for atrial fibrillation associated with omega-3 fatty acids, compared with mineral oil, was significantly higher (5.3% vs. 3.9%; P = .003).
In a third study (OMEMI), as Dr. Curfman reported, 1027 elderly patients who had recently had a myocardial infarction were randomly assigned to receive either a median dose of 1.8 g/day of omega-3 fatty acids (a combination of EPA and DHA) or corn oil. After 2 years, there was no significant difference between the two groups in primary composite cardiovascular endpoints, but 7.2% of the patients taking omega-3 fatty acids developed atrial fibrillation. In the corn oil group, this proportion was 4% (HR, 1.84; 95% CI, 0.98-3.45; P = .06).
The data from the four studies together indicate a potential dose-dependent risk for atrial fibrillation associated with omega-3 fatty acids, according to Dr. Curfman. At a dose of 4.0 g/day, there is a highly significant risk increase (almost double). With a median dose of 1.8 g/day, the risk increase (HR, 1.84) did not reach statistical significance. At a daily standard dose of 840 mg/day, an increase in risk could not be determined.
Dr. Curfman’s recommendation is that patients who take, or want to take, preparations with omega-3 fatty acids be informed of the potential development of arrhythmia at higher dosages. These patients also should undergo cardiological monitoring.
A version of this article first appeared on Medscape.com.
Dietary supplements that contain omega-3 fatty acids have been widely consumed for years. Researchers have been investigating the benefits of such preparations for cardiovascular, neurologic, and psychological conditions. A recently published study on omega-3 fatty acids and depression inspired neurologist Hans-Christoph Diener, MD, PhD, of the Institute for Epidemiology at the University Duisburg-Essen (Germany), to examine scientific publications concerning omega-3 fatty acids or fish-oil capsules in more detail.
Prevention of depression
Dr. Diener told the story of how he stumbled upon an interesting article in JAMA in December 2021. It was about a placebo-controlled study that investigated whether omega-3 fatty acids can prevent incident depression.
As the study authors reported, treatment with omega-3 preparations in adults aged 50 years or older without clinically relevant symptoms of depression at study initiation was associated with a small but statistically significant increase in the risk for depression or clinically relevant symptoms of depression. There was no difference in mood scale value, however, over a median follow-up of 5.3 years. According to the study authors, these results did not support the administration of omega-3 preparations for the prevention of depression.
This study was, as Dr. Diener said, somewhat negative, but it did arouse his interest in questions such as what biological effects omega-3 fatty acids have and what is known “about this topic with regard to neurology,” he said. When reviewing the literature, he noticed that there “were association studies, i.e., studies that describe that the intake of omega-3 fatty acids may possibly be associated with a lower risk of certain diseases.”
Beginning with the Inuit
It all started “with observations of the Inuit [population] in Greenland and Alaska after World War II, because it was remarked upon that these people ate a lot of fish and seal meat and had a very low incidence of cardiovascular diseases.” Over the years, a large number of association studies have been published, which may have encouraged the assumption that omega-3 fatty acids have positive health effects on various conditions, such as cardiovascular diseases, hyperlipidemia, type 2 diabetes, various malignancies, cognitive impairments, Alzheimer’s disease, depression and anxiety disorders, heart failure, slipped disks, ADHD, symptoms of menopause, rheumatoid arthritis, asthma, periodontitis, epilepsy, chemotherapy tolerance, premenstrual syndrome, and nonalcoholic fatty liver disease.
Dr. Diener believes that the problem is that these are association studies. But association does not mean that there is a causal relationship.
Disappointing study results
On the contrary, the results from the randomized placebo-controlled studies are truly frustrating, according to the neurologist. A meta-analysis of the use of omega-3 fatty acids in cardiovascular diseases included 86 studies with over 162,000 patients. According to Dr. Diener, it did not reveal any benefit for overall and cardiovascular mortality, nor any benefit for the reduction of myocardial infarction and stroke.
The results did indicate a trend, however, for reduced mortality in coronary heart disease. Even so, the number needed to treat for this was 334, which means that 334 people would have to take omega-3 fatty acids for years to prevent one fatal cardiac event.
Aside from this study, Dr. Diener found six studies on Alzheimer’s disease and three studies on dementia with patient populations between 600 and 800. In these studies, too, a positive effect of omega-3 fatty acids could not be identified. Then he discovered another 31 placebo-controlled studies of omega-3 fatty acids for the treatment or prevention of depression and anxiety disorder. Despite including 50,000 patients, these studies also did not show any positive effect.
“I see a significant discrepancy between the promotion of omega-3 fatty acids, whether it’s on television, in the ‘yellow’ [journalism] press, or in advertisements, and the actual scientific evidence,” said Dr. Diener. “At least from a neurological perspective, there is no evidence that omega-3 fatty acids have any benefit. This is true for strokes, dementia, Alzheimer’s disease, depression, and anxiety disorders.”
Potential adverse effects
Omega-3 fatty acids also have potentially adverse effects. The VITAL Rhythm study recently provided evidence that, depending on the dose, preparations with omega-3 fatty acids may increase the risk for atrial fibrillation. As the authors wrote, the results do not support taking omega-3 fatty acids to prevent atrial fibrillation.
In 2019, the global market for omega-3 fatty acids reached a value of $4.1 billion. This value is expected to double by 2025, according to a comment by Gregory Curfman, MD, deputy editor of JAMA and lecturer in health care policy at Harvard Medical School, Boston.
As Dr. Curfman wrote, this impressive amount of expenditure shows how beloved these products are and how strongly many people believe that omega-3 fatty acids are beneficial for their health. It is therefore important to know the potential risks of such preparations. One such example for this would be the risk for atrial fibrillation.
According to Dr. Curfman, in the last 2 years, four randomized clinical studies have provided data on the risk for atrial fibrillation associated with omega-3 fatty acids. In the STRENGTH study, 13,078 high-risk patients with cardiovascular diseases were randomly assigned to one of two groups. The subjects received either a high dose (4 g/day) of a combination of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) or corn oil. After a median of 42 months, there was no significant difference between the two groups in the primary composite cardiovascular endpoint, but more frequent atrial fibrillation in the omega-3 fatty acid group, compared with the corn oil group (2.2% vs. 1.3%; hazard ratio, 1.69; 95% confidence interval, 1.29-2.21; P < .001).
In the REDUCE-IT study, 8179 subjects were randomly assigned to a high dose (4 g/day, as in STRENGTH) of an omega-3 fatty acid preparation consisting of a purified EPA (icosapent ethyl) or mineral oil. After a median observation period of 4.9 years, icosapent ethyl was associated with a relative reduction of the primary composite cardiovascular endpoint by 25%, compared with mineral oil. As in the STRENGTH study, this study found that the risk for atrial fibrillation associated with omega-3 fatty acids, compared with mineral oil, was significantly higher (5.3% vs. 3.9%; P = .003).
In a third study (OMEMI), as Dr. Curfman reported, 1027 elderly patients who had recently had a myocardial infarction were randomly assigned to receive either a median dose of 1.8 g/day of omega-3 fatty acids (a combination of EPA and DHA) or corn oil. After 2 years, there was no significant difference between the two groups in primary composite cardiovascular endpoints, but 7.2% of the patients taking omega-3 fatty acids developed atrial fibrillation. In the corn oil group, this proportion was 4% (HR, 1.84; 95% CI, 0.98-3.45; P = .06).
The data from the four studies together indicate a potential dose-dependent risk for atrial fibrillation associated with omega-3 fatty acids, according to Dr. Curfman. At a dose of 4.0 g/day, there is a highly significant risk increase (almost double). With a median dose of 1.8 g/day, the risk increase (HR, 1.84) did not reach statistical significance. At a daily standard dose of 840 mg/day, an increase in risk could not be determined.
Dr. Curfman’s recommendation is that patients who take, or want to take, preparations with omega-3 fatty acids be informed of the potential development of arrhythmia at higher dosages. These patients also should undergo cardiological monitoring.
A version of this article first appeared on Medscape.com.