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Is walking speed following stroke a good predictor of recovery?
, suggests new research backed by imaging data.
In secondary analysis of a previous study, training enabled both “good” and “limited” walkers to increase travel distance during a 2-minute walk. However, for “dual-task” walking, good walkers improved their distance by approximately 10 m after training, whereas limited walkers improved by only 1 m. Brain imaging showed increased brain activity in the limited walkers, which could reduce cognitive resources available for performing a second task while walking.
These findings, which were published online May 30 in Clinical Rehabilitation, may explain the apparent lack of superiority, shown previously, of dual-task training compared with single-task training for patients with stroke and impaired walking ability, researchers noted.
“Imaging data were consistent with our hypothesis that walking automaticity might explain these results,” said lead author Johnny Collett, PhD, senior clinical research fellow at Oxford Brookes University, United Kingdom.
At baseline, participants who walked slowly had increased resting state connectivity between contralesional M1 and cortical areas associated with conscious gait control.
“In response to the intervention, we found increased connectivity with the precuneus in those who walked slowly at baseline, an adaptation that might support walking in more complex situations,” Dr. Collett said.
Benefits questioned
After stroke, many patients have difficulty walking while performing a second task, such as holding a conversation. Training in dual-task walking has provided uncertain benefits, according to clinical research.
In healthy individuals, walking is believed to be a largely automatic process that requires minimal executive resources. Previous studies have suggested that a certain minimum walking speed is required to enable automatic control of walking in the brain.
“We know that those with better walking ability after stroke are better able to cope with additional cognitive loads while walking,” said Dr. Collett. “Here, we proposed that increased automatic gait control may provide a mechanism whereby executive resources are freed up to attend to additional tasks,” he added.
The investigators further hypothesized that greater walking speed is required for automatic gait control. To test these hypotheses, they analyzed data from a previously conducted randomized trial of single- and dual-task walking interventions.
Trial participants were aged 18 years or older, had survived a stroke that had occurred at least 6 months before enrollment, had reduced 2-minute walk distance relative to their peers, and had no comorbid neurologic or psychologic disorders.
Over 10 weeks, participants underwent 20 sessions that included 30 minutes of walking on a treadmill. They were randomly assigned to undergo single-task walking or dual-task walking. The latter incorporated cognitive tasks as distractions.
Good versus limited walkers
In the current study, investigators analyzed various assessments that had been conducted at baseline and after completion of the training sessions, including distance on 2-minute walks with and without a distracting task. In addition, participants underwent imaging with functional near-infrared spectroscopy (fNIRS) and fMRI.
Using previous research as a basis, the researchers defined good walking speed as 0.8 m/sec. They categorized all participants, regardless of their intervention assignments, as having good walking capacity (0.8 m/sec or more) or limited walking capacity (less than 0.79 m/sec).
A total of 50 participants enrolled in the study (mean age, 62 years), and 45 completed the interventions. Of those who completed the interventions, 22 were randomly assigned to undergo single-task training, and 23 were assigned to dual-task training.
The researchers categorized 21 participants as having good walking capacity and 24 as having limited walking capacity. Participants in each category were divided approximately evenly between treatment assignments.
Barthel index score, which assesses functional independence, was higher in the group of good walkers.
Increased travel distance
Results showed that after the interventions, distance traveled during the single-task 2-minute walk increased by 8.9 m for good walkers and by 5.3 m for limited walkers. For the dual-task 2-minute walk, the distance traveled increased by 10.4 m among good walkers and by 1.3 m for limited walkers. Change from baseline on the dual-task walk was not significant for limited walkers.
There was no significant difference between good walkers and limited walkers in their perceptions of participation in community walking. Neither group increased its walking activity significantly following the interventions.
At baseline, limited walkers, in comparison with good walkers, had significantly greater activation in the contralesional hemisphere during dual-task walking, which consisted of incorporating a planning task.
In contrast, for many good walkers, there was a decrease in activation during dual-task walking. Activation in the contralesional hemisphere correlated negatively with dual-task 2-minute walk distance.
The researchers also found a negative correlation between activation and dual-task 2-minute walk distance when the second task was the Stroop task.
Initial step
“The original trial was never designed or powered to compare groups formed by walking speed or test our automaticity hypothesis, and the results need to be viewed within this context,” said Dr. Collett. The small sample size did not allow the researchers to detect small effects of the intervention, especially in the imaging data, he added.
It also prevented the investigators from comparing limited walking and good walking groups according to whether they underwent the single-task or dual-task intervention, “which would be a superior way to investigate our hypotheses,” Dr. Collett said.
“The result of this study should be seen as exploratory, with further investigation needed,” he noted.
Helping stroke survivors to walk in the community is challenging, and new interventions that enable them to navigate complex surroundings need to be designed, said Dr. Collett. “Research is required to better understand the conscious and automatic contribution to gait control, especially with neurological impairment,” he added.
Overall, “our results suggest that improving automatic walking may be an initial step to improve capacity to respond to more complex walking interventions. However, [future] trials are required to test this,” he concluded.
The next frontier?
Commenting on the findings, Louis R. Caplan, MD, professor of neurology at Harvard University and senior neurologist at Beth Israel Deaconess Medical Center, Boston, said that “recovery and rehab are going to be the next frontier in stroke neurology, because there has to be a limitation in the present emphasis on acute care.”
Some patients do not receive acute care on time, and current treatment is not curative, added Dr. Caplan, who was not involved with the research.
Little scientific attention has been paid to how doctors can enhance recovery after stroke, what interventions delay recovery, and what the natural history of recovery is, he said. “This is a very nice study about that.”
Although the study’s methodology was sound, there were some limitations, including that strokes and underlying brain lesions were heterogeneous and that the study population was relatively small, Dr. Caplan said.
He added that “it’s a difficult study to do” and that it is difficult to organize participants into homogeneous groups.
Another limitation cited was lack of long-term follow-up that could indicate whether training provided sustained improvements in walking.
“It would be nice to revisit the same people later and see if their walking has improved, if they’re doing it differently, and if their subjective responses are different,” said Dr. Caplan.
In addition, the study did not examine whether the interventions made it easier for participants to walk with other people or to socialize more. “It may be that it really requires some time for them to gain confidence and for them to integrate that into their social network,” Dr. Caplan said.
“I would call it a proof-of-principle study, not a final study,” he noted. “It’s a study that shows that you can scientifically study rehab” and indicates the possible methodology that could be used.
The study was funded by the Stroke Association. Dr. Collett and Dr. Caplan have reported no relevant financial relationships.
A version of this article first appeared on Medscape.com.
, suggests new research backed by imaging data.
In secondary analysis of a previous study, training enabled both “good” and “limited” walkers to increase travel distance during a 2-minute walk. However, for “dual-task” walking, good walkers improved their distance by approximately 10 m after training, whereas limited walkers improved by only 1 m. Brain imaging showed increased brain activity in the limited walkers, which could reduce cognitive resources available for performing a second task while walking.
These findings, which were published online May 30 in Clinical Rehabilitation, may explain the apparent lack of superiority, shown previously, of dual-task training compared with single-task training for patients with stroke and impaired walking ability, researchers noted.
“Imaging data were consistent with our hypothesis that walking automaticity might explain these results,” said lead author Johnny Collett, PhD, senior clinical research fellow at Oxford Brookes University, United Kingdom.
At baseline, participants who walked slowly had increased resting state connectivity between contralesional M1 and cortical areas associated with conscious gait control.
“In response to the intervention, we found increased connectivity with the precuneus in those who walked slowly at baseline, an adaptation that might support walking in more complex situations,” Dr. Collett said.
Benefits questioned
After stroke, many patients have difficulty walking while performing a second task, such as holding a conversation. Training in dual-task walking has provided uncertain benefits, according to clinical research.
In healthy individuals, walking is believed to be a largely automatic process that requires minimal executive resources. Previous studies have suggested that a certain minimum walking speed is required to enable automatic control of walking in the brain.
“We know that those with better walking ability after stroke are better able to cope with additional cognitive loads while walking,” said Dr. Collett. “Here, we proposed that increased automatic gait control may provide a mechanism whereby executive resources are freed up to attend to additional tasks,” he added.
The investigators further hypothesized that greater walking speed is required for automatic gait control. To test these hypotheses, they analyzed data from a previously conducted randomized trial of single- and dual-task walking interventions.
Trial participants were aged 18 years or older, had survived a stroke that had occurred at least 6 months before enrollment, had reduced 2-minute walk distance relative to their peers, and had no comorbid neurologic or psychologic disorders.
Over 10 weeks, participants underwent 20 sessions that included 30 minutes of walking on a treadmill. They were randomly assigned to undergo single-task walking or dual-task walking. The latter incorporated cognitive tasks as distractions.
Good versus limited walkers
In the current study, investigators analyzed various assessments that had been conducted at baseline and after completion of the training sessions, including distance on 2-minute walks with and without a distracting task. In addition, participants underwent imaging with functional near-infrared spectroscopy (fNIRS) and fMRI.
Using previous research as a basis, the researchers defined good walking speed as 0.8 m/sec. They categorized all participants, regardless of their intervention assignments, as having good walking capacity (0.8 m/sec or more) or limited walking capacity (less than 0.79 m/sec).
A total of 50 participants enrolled in the study (mean age, 62 years), and 45 completed the interventions. Of those who completed the interventions, 22 were randomly assigned to undergo single-task training, and 23 were assigned to dual-task training.
The researchers categorized 21 participants as having good walking capacity and 24 as having limited walking capacity. Participants in each category were divided approximately evenly between treatment assignments.
Barthel index score, which assesses functional independence, was higher in the group of good walkers.
Increased travel distance
Results showed that after the interventions, distance traveled during the single-task 2-minute walk increased by 8.9 m for good walkers and by 5.3 m for limited walkers. For the dual-task 2-minute walk, the distance traveled increased by 10.4 m among good walkers and by 1.3 m for limited walkers. Change from baseline on the dual-task walk was not significant for limited walkers.
There was no significant difference between good walkers and limited walkers in their perceptions of participation in community walking. Neither group increased its walking activity significantly following the interventions.
At baseline, limited walkers, in comparison with good walkers, had significantly greater activation in the contralesional hemisphere during dual-task walking, which consisted of incorporating a planning task.
In contrast, for many good walkers, there was a decrease in activation during dual-task walking. Activation in the contralesional hemisphere correlated negatively with dual-task 2-minute walk distance.
The researchers also found a negative correlation between activation and dual-task 2-minute walk distance when the second task was the Stroop task.
Initial step
“The original trial was never designed or powered to compare groups formed by walking speed or test our automaticity hypothesis, and the results need to be viewed within this context,” said Dr. Collett. The small sample size did not allow the researchers to detect small effects of the intervention, especially in the imaging data, he added.
It also prevented the investigators from comparing limited walking and good walking groups according to whether they underwent the single-task or dual-task intervention, “which would be a superior way to investigate our hypotheses,” Dr. Collett said.
“The result of this study should be seen as exploratory, with further investigation needed,” he noted.
Helping stroke survivors to walk in the community is challenging, and new interventions that enable them to navigate complex surroundings need to be designed, said Dr. Collett. “Research is required to better understand the conscious and automatic contribution to gait control, especially with neurological impairment,” he added.
Overall, “our results suggest that improving automatic walking may be an initial step to improve capacity to respond to more complex walking interventions. However, [future] trials are required to test this,” he concluded.
The next frontier?
Commenting on the findings, Louis R. Caplan, MD, professor of neurology at Harvard University and senior neurologist at Beth Israel Deaconess Medical Center, Boston, said that “recovery and rehab are going to be the next frontier in stroke neurology, because there has to be a limitation in the present emphasis on acute care.”
Some patients do not receive acute care on time, and current treatment is not curative, added Dr. Caplan, who was not involved with the research.
Little scientific attention has been paid to how doctors can enhance recovery after stroke, what interventions delay recovery, and what the natural history of recovery is, he said. “This is a very nice study about that.”
Although the study’s methodology was sound, there were some limitations, including that strokes and underlying brain lesions were heterogeneous and that the study population was relatively small, Dr. Caplan said.
He added that “it’s a difficult study to do” and that it is difficult to organize participants into homogeneous groups.
Another limitation cited was lack of long-term follow-up that could indicate whether training provided sustained improvements in walking.
“It would be nice to revisit the same people later and see if their walking has improved, if they’re doing it differently, and if their subjective responses are different,” said Dr. Caplan.
In addition, the study did not examine whether the interventions made it easier for participants to walk with other people or to socialize more. “It may be that it really requires some time for them to gain confidence and for them to integrate that into their social network,” Dr. Caplan said.
“I would call it a proof-of-principle study, not a final study,” he noted. “It’s a study that shows that you can scientifically study rehab” and indicates the possible methodology that could be used.
The study was funded by the Stroke Association. Dr. Collett and Dr. Caplan have reported no relevant financial relationships.
A version of this article first appeared on Medscape.com.
, suggests new research backed by imaging data.
In secondary analysis of a previous study, training enabled both “good” and “limited” walkers to increase travel distance during a 2-minute walk. However, for “dual-task” walking, good walkers improved their distance by approximately 10 m after training, whereas limited walkers improved by only 1 m. Brain imaging showed increased brain activity in the limited walkers, which could reduce cognitive resources available for performing a second task while walking.
These findings, which were published online May 30 in Clinical Rehabilitation, may explain the apparent lack of superiority, shown previously, of dual-task training compared with single-task training for patients with stroke and impaired walking ability, researchers noted.
“Imaging data were consistent with our hypothesis that walking automaticity might explain these results,” said lead author Johnny Collett, PhD, senior clinical research fellow at Oxford Brookes University, United Kingdom.
At baseline, participants who walked slowly had increased resting state connectivity between contralesional M1 and cortical areas associated with conscious gait control.
“In response to the intervention, we found increased connectivity with the precuneus in those who walked slowly at baseline, an adaptation that might support walking in more complex situations,” Dr. Collett said.
Benefits questioned
After stroke, many patients have difficulty walking while performing a second task, such as holding a conversation. Training in dual-task walking has provided uncertain benefits, according to clinical research.
In healthy individuals, walking is believed to be a largely automatic process that requires minimal executive resources. Previous studies have suggested that a certain minimum walking speed is required to enable automatic control of walking in the brain.
“We know that those with better walking ability after stroke are better able to cope with additional cognitive loads while walking,” said Dr. Collett. “Here, we proposed that increased automatic gait control may provide a mechanism whereby executive resources are freed up to attend to additional tasks,” he added.
The investigators further hypothesized that greater walking speed is required for automatic gait control. To test these hypotheses, they analyzed data from a previously conducted randomized trial of single- and dual-task walking interventions.
Trial participants were aged 18 years or older, had survived a stroke that had occurred at least 6 months before enrollment, had reduced 2-minute walk distance relative to their peers, and had no comorbid neurologic or psychologic disorders.
Over 10 weeks, participants underwent 20 sessions that included 30 minutes of walking on a treadmill. They were randomly assigned to undergo single-task walking or dual-task walking. The latter incorporated cognitive tasks as distractions.
Good versus limited walkers
In the current study, investigators analyzed various assessments that had been conducted at baseline and after completion of the training sessions, including distance on 2-minute walks with and without a distracting task. In addition, participants underwent imaging with functional near-infrared spectroscopy (fNIRS) and fMRI.
Using previous research as a basis, the researchers defined good walking speed as 0.8 m/sec. They categorized all participants, regardless of their intervention assignments, as having good walking capacity (0.8 m/sec or more) or limited walking capacity (less than 0.79 m/sec).
A total of 50 participants enrolled in the study (mean age, 62 years), and 45 completed the interventions. Of those who completed the interventions, 22 were randomly assigned to undergo single-task training, and 23 were assigned to dual-task training.
The researchers categorized 21 participants as having good walking capacity and 24 as having limited walking capacity. Participants in each category were divided approximately evenly between treatment assignments.
Barthel index score, which assesses functional independence, was higher in the group of good walkers.
Increased travel distance
Results showed that after the interventions, distance traveled during the single-task 2-minute walk increased by 8.9 m for good walkers and by 5.3 m for limited walkers. For the dual-task 2-minute walk, the distance traveled increased by 10.4 m among good walkers and by 1.3 m for limited walkers. Change from baseline on the dual-task walk was not significant for limited walkers.
There was no significant difference between good walkers and limited walkers in their perceptions of participation in community walking. Neither group increased its walking activity significantly following the interventions.
At baseline, limited walkers, in comparison with good walkers, had significantly greater activation in the contralesional hemisphere during dual-task walking, which consisted of incorporating a planning task.
In contrast, for many good walkers, there was a decrease in activation during dual-task walking. Activation in the contralesional hemisphere correlated negatively with dual-task 2-minute walk distance.
The researchers also found a negative correlation between activation and dual-task 2-minute walk distance when the second task was the Stroop task.
Initial step
“The original trial was never designed or powered to compare groups formed by walking speed or test our automaticity hypothesis, and the results need to be viewed within this context,” said Dr. Collett. The small sample size did not allow the researchers to detect small effects of the intervention, especially in the imaging data, he added.
It also prevented the investigators from comparing limited walking and good walking groups according to whether they underwent the single-task or dual-task intervention, “which would be a superior way to investigate our hypotheses,” Dr. Collett said.
“The result of this study should be seen as exploratory, with further investigation needed,” he noted.
Helping stroke survivors to walk in the community is challenging, and new interventions that enable them to navigate complex surroundings need to be designed, said Dr. Collett. “Research is required to better understand the conscious and automatic contribution to gait control, especially with neurological impairment,” he added.
Overall, “our results suggest that improving automatic walking may be an initial step to improve capacity to respond to more complex walking interventions. However, [future] trials are required to test this,” he concluded.
The next frontier?
Commenting on the findings, Louis R. Caplan, MD, professor of neurology at Harvard University and senior neurologist at Beth Israel Deaconess Medical Center, Boston, said that “recovery and rehab are going to be the next frontier in stroke neurology, because there has to be a limitation in the present emphasis on acute care.”
Some patients do not receive acute care on time, and current treatment is not curative, added Dr. Caplan, who was not involved with the research.
Little scientific attention has been paid to how doctors can enhance recovery after stroke, what interventions delay recovery, and what the natural history of recovery is, he said. “This is a very nice study about that.”
Although the study’s methodology was sound, there were some limitations, including that strokes and underlying brain lesions were heterogeneous and that the study population was relatively small, Dr. Caplan said.
He added that “it’s a difficult study to do” and that it is difficult to organize participants into homogeneous groups.
Another limitation cited was lack of long-term follow-up that could indicate whether training provided sustained improvements in walking.
“It would be nice to revisit the same people later and see if their walking has improved, if they’re doing it differently, and if their subjective responses are different,” said Dr. Caplan.
In addition, the study did not examine whether the interventions made it easier for participants to walk with other people or to socialize more. “It may be that it really requires some time for them to gain confidence and for them to integrate that into their social network,” Dr. Caplan said.
“I would call it a proof-of-principle study, not a final study,” he noted. “It’s a study that shows that you can scientifically study rehab” and indicates the possible methodology that could be used.
The study was funded by the Stroke Association. Dr. Collett and Dr. Caplan have reported no relevant financial relationships.
A version of this article first appeared on Medscape.com.
From Clinical Rehabilitation
What’s best for diabetes after metformin? GRADE outdated at outset
Liraglutide and insulin glargine outperformed glimepiride and sitagliptin as single add-on agents to metformin for treating patients with type 2 diabetes in a multicenter U.S. trial that randomized just over 5,000 patients.
. Results were reported at the virtual American Diabetes Association (ADA) 81st Scientific Sessions.
The comparison included two oral medications – the sulfonylurea glimepiride and dipeptidyl peptidase-4 (DPP-4) inhibitor sitagliptin – and two injectable medications – insulin glargine and glucagon-like peptide 1 (GLP-1) receptor agonist liraglutide.
The primary endpoint was change in A1c level and overall glycemic control. Secondary endpoints include changes in weight, as well as cardiovascular, renal, gastrointestinal, and other complications.
For the primary endpoint – keeping A1c levels below 7% – liraglutide and the basal insulin glargine both did this best and were almost equivalent.
During the average 5-year follow-up, the rates of patients progressing to a confirmed A1c of 7% or higher were 67% among patients randomized to insulin glargine, 68% maintained on liraglutide, 72% taking the sulfonylurea glimepiride, and 77% taking sitagliptin, reported John M. Lachin, ScD, a biostatistician at George Washington University, Washington.
Too soon for take-aways, or are the data already obsolete?
“The ultimate goal of GRADE is to help clinicians select the therapies that will work best for individual patients, as diabetes care is not a one-size-fits all approach,” noted David M. Nathan, MD, chair of the study and director of the Diabetes Center at Massachusetts General Hospital, in an ADA press release.
Dr. Nathan, as well as several other members of the GRADE trial steering committee who presented results, repeatedly cautioned that the findings were preliminary because they represent 90% of outcomes, with the remaining 10% still to be adjudicated.
“We undertook this study to fill a gap in the guidelines,” said investigator Deborah J. Wexler, MD, clinical director of the Diabetes Center at Massachusetts General Hospital in Boston. “I would like to have all the results in ... before I comment on how the guidelines should change.”
“The metabolic data are solid, but the cardiovascular disease data are preliminary,” warned Dr. Nathan.
But that didn’t stop some from drawing their own conclusions, with Julio Rosenstock, MD, who comoderated the session but was not involved with the study, giving his own opinion.
“A pleasant surprise was the performance of basal insulin,” he said, calling the findings “a vindication” for basal insulin as a treatment for the types of patients with type 2 diabetes that enrolled in the study.
Steven E. Kahn, MB, ChB, another GRADE co-investigator agreed. “Based on the results, guidelines should say that you add insulin early on,” he observed.
A generic basal insulin and a generic sulfonylurea are both reasonable options, after metformin, for patients with limited resources, added Dr. Kahn, an endocrinologist and professor at the University of Washington, Seattle.
Dr. Rosenstock, director of the Dallas Diabetes Research Center, also saw the results as an indictment of agents in the DDP-4 inhibitor class, such as sitagliptin.
The DPP-4 inhibitors generate $9 billion a year, he said, wondering whether it “is justifiable to put them on the same level as other agents?”
Meanwhile the assigned discussant, David R. Matthews, DPhil, a professor of diabetes medicine at the University of Oxford, England – while congratulating the investigators on certain aspects of the study – said it ultimately fell short because it didn’t include an arm with an SGLT2 inhibitor.
“We should kick the authors for missing out on SGLT2 inhibitors,” Dr. Matthews said. “The omission means that the GRADE data are already obsolescent.”
In reply, Dr. Nathan admitted “we feel bad we did not include” an SGLT2 inhibitor, but he vigorously defended the dilemma faced by the trial’s organizers.
Oral SGLT2 inhibitors were not “well-established drugs” for type 2 diabetes when enrollment launched in 2013, and the researchers were wary of including what could turn out to be a problematic agent soon after controversy over the safety of agents in the thiazolidinedione drug class (such as rosiglitazone), he explained.
They also realized that adding a fifth drug to the study would necessitate doubling enrollment size, which would have undercut the funding plans already in place.
Dr. Matthews also derided GRADE as being underpowered to adequately address the impact of the tested agents on major adverse cardiovascular events (MACE) and hospitalizations for heart failure and too U.S.-centric to be generalizable elsewhere.
A study with lots of data
The roughly 5,000 patients enrolled in GRADE were an average age of 57 years old, 64% were men, 66% were White, and 20% were Black. They had had type 2 diabetes, on average, for 4.2 years. Mean body mass index at entry was about 34 kg/m2, average A1c was 7.5%, and average estimated glomerular filtration rate was 95 mL/min/1.73m2. The trial included a 6-12 week run-in period during which background metformin treatment was optimized and led to average A1c levels less than 7%.
Patients were then randomized to one of the four agents as add-on treatment.
Both liraglutide and insulin glargine performed well on many of the numerous metrics in the data-rich trial, largely funded by two branches of the National Institutes of Health, with commercial involvement limited to free supplies of the study drugs.
The secondary metabolic outcome, of disease progressing to a confirmed A1c of 7.5%, was reached by 39% of patients taking insulin glargine, significantly lower than the rate of 46% among patients taking liraglutide, and that rate, in turn, was significantly below the 50% rate among patients taking glimepiride and the 55% rate of those taking sitagliptin.
Mean doses of the second-line agents after 4 years of treatment were 38.3 units/day for glargine, 3.5 mg/day for glimepiride, 1.3 mg/day for subcutaneous liraglutide, and 82.9 mg/day for sitagliptin.
A trio of cardiovascular outcomes showed one significant benefit of liraglutide over the other three drugs for the endpoint of any cardiovascular event, which included not only major adverse cardiovascular events (MACE; cardiovascular death, myocardial infarction, or stroke), but also several other event types, including heart failure requiring hospitalization, unstable angina requiring hospitalization, revascularization or any arterial repairs, stent thrombosis, or transient ischemic attack.
For the endpoint of any cardiovascular event, the rate was 5.8% for patients taking liraglutide, significantly less than the rate of 7.6% of those taking insulin glargine, 8.0% for glimepiride, and 8.6% for sitagliptin, reported John B. Buse, MD, PhD, professor, chief of endocrinology, and director of the Diabetes Center at the University of North Carolina at Chapel Hill.
For each of the other two main cardiovascular endpoints – MACE and hospitalization for heart failure – liraglutide had a numeric advantage over the other three drugs but failed to reach significance.
Patients taking liraglutide also had a smaller but not significantly different point estimate for all-cause death, at 2.1%, compared with 3.1%-3.4% in the other three groups.
And, Dr. Nathan emphasized, the cardiovascular disease data are still considered preliminary.
Liraglutide scored a pair of additional outcome victories. Its use resulted in a significantly lower rate of patients who progressed during follow-up to either needing antihypertensive medications or having their blood pressure rise above 140/90 mm Hg compared with the other three drugs. (At baseline, average blood pressure for all patients was 128/77 mm Hg.)
And after 4 years, patients taking liraglutide lost an average of about 4 kg (8.8 lb) from their baseline weight (which averaged about 100 kg [220 lb]), roughly the same as patients taking sitagliptin but significantly better than with glimepiride or insulin glargine. Patients taking glargine gained a small amount of weight on average during their first couple of years of treatment, roughly 1 kg, but returned to around their baseline weight by the end of 4 years.
Four drugs performed equally well for some outcomes
Finally, the four drugs had similar results for some outcomes. This included their effects on renal function, distal sensory polyneuropathy, and low-density lipoprotein (LDL) cholesterol.
The four agents also had roughly similar safety profiles, with rates of serious adverse events all falling within the tight range of 33%-37%.
But the rate of severe hypoglycemic episodes that required assistance to treat showed significant separation, ranging from 2.3% for glimepiride, 1.4% for glargine, 0.9% for liraglutide, and 0.7% for sitagliptin. Gastrointestinal symptoms occurred in about 50% of patients in three of the treatment groups but were significantly higher in those taking liraglutide, affecting 60%.
GRADE received no commercial funding. Dr. Wexler has reported serving on data monitoring committees for Novo Nordisk. Dr. Buse has reported being a consultant for and holding stock in numerous companies. Dr. Rosenstock has reported being an advisor or consultant to Applied Therapeutics, Boehringer Ingelheim, Hanmi Pharmaceutical, Intarcia Therapeutics, Lilly, Novo Nordisk, Oramed, and Sanofi and has received research support from numerous companies. Dr. Kahn has reported being an advisor to or speaker on behalf of Bayer, Boehringer Ingelheim, Casma Therapeutics, Intarcia Therapeutics, Lilly, Merck, Novo Nordisk, Pfizer, and Third Rock Ventures. Dr. Matthews has reported receiving lecture and advisor fees from Merck, Novartis, Novo Nordisk, Sanofi Aventis, and Servier. Dr. Lachin and Dr. Nathan have reported no relevant financial relationships.
A version of this article first appeared on Medscape.com.
Liraglutide and insulin glargine outperformed glimepiride and sitagliptin as single add-on agents to metformin for treating patients with type 2 diabetes in a multicenter U.S. trial that randomized just over 5,000 patients.
. Results were reported at the virtual American Diabetes Association (ADA) 81st Scientific Sessions.
The comparison included two oral medications – the sulfonylurea glimepiride and dipeptidyl peptidase-4 (DPP-4) inhibitor sitagliptin – and two injectable medications – insulin glargine and glucagon-like peptide 1 (GLP-1) receptor agonist liraglutide.
The primary endpoint was change in A1c level and overall glycemic control. Secondary endpoints include changes in weight, as well as cardiovascular, renal, gastrointestinal, and other complications.
For the primary endpoint – keeping A1c levels below 7% – liraglutide and the basal insulin glargine both did this best and were almost equivalent.
During the average 5-year follow-up, the rates of patients progressing to a confirmed A1c of 7% or higher were 67% among patients randomized to insulin glargine, 68% maintained on liraglutide, 72% taking the sulfonylurea glimepiride, and 77% taking sitagliptin, reported John M. Lachin, ScD, a biostatistician at George Washington University, Washington.
Too soon for take-aways, or are the data already obsolete?
“The ultimate goal of GRADE is to help clinicians select the therapies that will work best for individual patients, as diabetes care is not a one-size-fits all approach,” noted David M. Nathan, MD, chair of the study and director of the Diabetes Center at Massachusetts General Hospital, in an ADA press release.
Dr. Nathan, as well as several other members of the GRADE trial steering committee who presented results, repeatedly cautioned that the findings were preliminary because they represent 90% of outcomes, with the remaining 10% still to be adjudicated.
“We undertook this study to fill a gap in the guidelines,” said investigator Deborah J. Wexler, MD, clinical director of the Diabetes Center at Massachusetts General Hospital in Boston. “I would like to have all the results in ... before I comment on how the guidelines should change.”
“The metabolic data are solid, but the cardiovascular disease data are preliminary,” warned Dr. Nathan.
But that didn’t stop some from drawing their own conclusions, with Julio Rosenstock, MD, who comoderated the session but was not involved with the study, giving his own opinion.
“A pleasant surprise was the performance of basal insulin,” he said, calling the findings “a vindication” for basal insulin as a treatment for the types of patients with type 2 diabetes that enrolled in the study.
Steven E. Kahn, MB, ChB, another GRADE co-investigator agreed. “Based on the results, guidelines should say that you add insulin early on,” he observed.
A generic basal insulin and a generic sulfonylurea are both reasonable options, after metformin, for patients with limited resources, added Dr. Kahn, an endocrinologist and professor at the University of Washington, Seattle.
Dr. Rosenstock, director of the Dallas Diabetes Research Center, also saw the results as an indictment of agents in the DDP-4 inhibitor class, such as sitagliptin.
The DPP-4 inhibitors generate $9 billion a year, he said, wondering whether it “is justifiable to put them on the same level as other agents?”
Meanwhile the assigned discussant, David R. Matthews, DPhil, a professor of diabetes medicine at the University of Oxford, England – while congratulating the investigators on certain aspects of the study – said it ultimately fell short because it didn’t include an arm with an SGLT2 inhibitor.
“We should kick the authors for missing out on SGLT2 inhibitors,” Dr. Matthews said. “The omission means that the GRADE data are already obsolescent.”
In reply, Dr. Nathan admitted “we feel bad we did not include” an SGLT2 inhibitor, but he vigorously defended the dilemma faced by the trial’s organizers.
Oral SGLT2 inhibitors were not “well-established drugs” for type 2 diabetes when enrollment launched in 2013, and the researchers were wary of including what could turn out to be a problematic agent soon after controversy over the safety of agents in the thiazolidinedione drug class (such as rosiglitazone), he explained.
They also realized that adding a fifth drug to the study would necessitate doubling enrollment size, which would have undercut the funding plans already in place.
Dr. Matthews also derided GRADE as being underpowered to adequately address the impact of the tested agents on major adverse cardiovascular events (MACE) and hospitalizations for heart failure and too U.S.-centric to be generalizable elsewhere.
A study with lots of data
The roughly 5,000 patients enrolled in GRADE were an average age of 57 years old, 64% were men, 66% were White, and 20% were Black. They had had type 2 diabetes, on average, for 4.2 years. Mean body mass index at entry was about 34 kg/m2, average A1c was 7.5%, and average estimated glomerular filtration rate was 95 mL/min/1.73m2. The trial included a 6-12 week run-in period during which background metformin treatment was optimized and led to average A1c levels less than 7%.
Patients were then randomized to one of the four agents as add-on treatment.
Both liraglutide and insulin glargine performed well on many of the numerous metrics in the data-rich trial, largely funded by two branches of the National Institutes of Health, with commercial involvement limited to free supplies of the study drugs.
The secondary metabolic outcome, of disease progressing to a confirmed A1c of 7.5%, was reached by 39% of patients taking insulin glargine, significantly lower than the rate of 46% among patients taking liraglutide, and that rate, in turn, was significantly below the 50% rate among patients taking glimepiride and the 55% rate of those taking sitagliptin.
Mean doses of the second-line agents after 4 years of treatment were 38.3 units/day for glargine, 3.5 mg/day for glimepiride, 1.3 mg/day for subcutaneous liraglutide, and 82.9 mg/day for sitagliptin.
A trio of cardiovascular outcomes showed one significant benefit of liraglutide over the other three drugs for the endpoint of any cardiovascular event, which included not only major adverse cardiovascular events (MACE; cardiovascular death, myocardial infarction, or stroke), but also several other event types, including heart failure requiring hospitalization, unstable angina requiring hospitalization, revascularization or any arterial repairs, stent thrombosis, or transient ischemic attack.
For the endpoint of any cardiovascular event, the rate was 5.8% for patients taking liraglutide, significantly less than the rate of 7.6% of those taking insulin glargine, 8.0% for glimepiride, and 8.6% for sitagliptin, reported John B. Buse, MD, PhD, professor, chief of endocrinology, and director of the Diabetes Center at the University of North Carolina at Chapel Hill.
For each of the other two main cardiovascular endpoints – MACE and hospitalization for heart failure – liraglutide had a numeric advantage over the other three drugs but failed to reach significance.
Patients taking liraglutide also had a smaller but not significantly different point estimate for all-cause death, at 2.1%, compared with 3.1%-3.4% in the other three groups.
And, Dr. Nathan emphasized, the cardiovascular disease data are still considered preliminary.
Liraglutide scored a pair of additional outcome victories. Its use resulted in a significantly lower rate of patients who progressed during follow-up to either needing antihypertensive medications or having their blood pressure rise above 140/90 mm Hg compared with the other three drugs. (At baseline, average blood pressure for all patients was 128/77 mm Hg.)
And after 4 years, patients taking liraglutide lost an average of about 4 kg (8.8 lb) from their baseline weight (which averaged about 100 kg [220 lb]), roughly the same as patients taking sitagliptin but significantly better than with glimepiride or insulin glargine. Patients taking glargine gained a small amount of weight on average during their first couple of years of treatment, roughly 1 kg, but returned to around their baseline weight by the end of 4 years.
Four drugs performed equally well for some outcomes
Finally, the four drugs had similar results for some outcomes. This included their effects on renal function, distal sensory polyneuropathy, and low-density lipoprotein (LDL) cholesterol.
The four agents also had roughly similar safety profiles, with rates of serious adverse events all falling within the tight range of 33%-37%.
But the rate of severe hypoglycemic episodes that required assistance to treat showed significant separation, ranging from 2.3% for glimepiride, 1.4% for glargine, 0.9% for liraglutide, and 0.7% for sitagliptin. Gastrointestinal symptoms occurred in about 50% of patients in three of the treatment groups but were significantly higher in those taking liraglutide, affecting 60%.
GRADE received no commercial funding. Dr. Wexler has reported serving on data monitoring committees for Novo Nordisk. Dr. Buse has reported being a consultant for and holding stock in numerous companies. Dr. Rosenstock has reported being an advisor or consultant to Applied Therapeutics, Boehringer Ingelheim, Hanmi Pharmaceutical, Intarcia Therapeutics, Lilly, Novo Nordisk, Oramed, and Sanofi and has received research support from numerous companies. Dr. Kahn has reported being an advisor to or speaker on behalf of Bayer, Boehringer Ingelheim, Casma Therapeutics, Intarcia Therapeutics, Lilly, Merck, Novo Nordisk, Pfizer, and Third Rock Ventures. Dr. Matthews has reported receiving lecture and advisor fees from Merck, Novartis, Novo Nordisk, Sanofi Aventis, and Servier. Dr. Lachin and Dr. Nathan have reported no relevant financial relationships.
A version of this article first appeared on Medscape.com.
Liraglutide and insulin glargine outperformed glimepiride and sitagliptin as single add-on agents to metformin for treating patients with type 2 diabetes in a multicenter U.S. trial that randomized just over 5,000 patients.
. Results were reported at the virtual American Diabetes Association (ADA) 81st Scientific Sessions.
The comparison included two oral medications – the sulfonylurea glimepiride and dipeptidyl peptidase-4 (DPP-4) inhibitor sitagliptin – and two injectable medications – insulin glargine and glucagon-like peptide 1 (GLP-1) receptor agonist liraglutide.
The primary endpoint was change in A1c level and overall glycemic control. Secondary endpoints include changes in weight, as well as cardiovascular, renal, gastrointestinal, and other complications.
For the primary endpoint – keeping A1c levels below 7% – liraglutide and the basal insulin glargine both did this best and were almost equivalent.
During the average 5-year follow-up, the rates of patients progressing to a confirmed A1c of 7% or higher were 67% among patients randomized to insulin glargine, 68% maintained on liraglutide, 72% taking the sulfonylurea glimepiride, and 77% taking sitagliptin, reported John M. Lachin, ScD, a biostatistician at George Washington University, Washington.
Too soon for take-aways, or are the data already obsolete?
“The ultimate goal of GRADE is to help clinicians select the therapies that will work best for individual patients, as diabetes care is not a one-size-fits all approach,” noted David M. Nathan, MD, chair of the study and director of the Diabetes Center at Massachusetts General Hospital, in an ADA press release.
Dr. Nathan, as well as several other members of the GRADE trial steering committee who presented results, repeatedly cautioned that the findings were preliminary because they represent 90% of outcomes, with the remaining 10% still to be adjudicated.
“We undertook this study to fill a gap in the guidelines,” said investigator Deborah J. Wexler, MD, clinical director of the Diabetes Center at Massachusetts General Hospital in Boston. “I would like to have all the results in ... before I comment on how the guidelines should change.”
“The metabolic data are solid, but the cardiovascular disease data are preliminary,” warned Dr. Nathan.
But that didn’t stop some from drawing their own conclusions, with Julio Rosenstock, MD, who comoderated the session but was not involved with the study, giving his own opinion.
“A pleasant surprise was the performance of basal insulin,” he said, calling the findings “a vindication” for basal insulin as a treatment for the types of patients with type 2 diabetes that enrolled in the study.
Steven E. Kahn, MB, ChB, another GRADE co-investigator agreed. “Based on the results, guidelines should say that you add insulin early on,” he observed.
A generic basal insulin and a generic sulfonylurea are both reasonable options, after metformin, for patients with limited resources, added Dr. Kahn, an endocrinologist and professor at the University of Washington, Seattle.
Dr. Rosenstock, director of the Dallas Diabetes Research Center, also saw the results as an indictment of agents in the DDP-4 inhibitor class, such as sitagliptin.
The DPP-4 inhibitors generate $9 billion a year, he said, wondering whether it “is justifiable to put them on the same level as other agents?”
Meanwhile the assigned discussant, David R. Matthews, DPhil, a professor of diabetes medicine at the University of Oxford, England – while congratulating the investigators on certain aspects of the study – said it ultimately fell short because it didn’t include an arm with an SGLT2 inhibitor.
“We should kick the authors for missing out on SGLT2 inhibitors,” Dr. Matthews said. “The omission means that the GRADE data are already obsolescent.”
In reply, Dr. Nathan admitted “we feel bad we did not include” an SGLT2 inhibitor, but he vigorously defended the dilemma faced by the trial’s organizers.
Oral SGLT2 inhibitors were not “well-established drugs” for type 2 diabetes when enrollment launched in 2013, and the researchers were wary of including what could turn out to be a problematic agent soon after controversy over the safety of agents in the thiazolidinedione drug class (such as rosiglitazone), he explained.
They also realized that adding a fifth drug to the study would necessitate doubling enrollment size, which would have undercut the funding plans already in place.
Dr. Matthews also derided GRADE as being underpowered to adequately address the impact of the tested agents on major adverse cardiovascular events (MACE) and hospitalizations for heart failure and too U.S.-centric to be generalizable elsewhere.
A study with lots of data
The roughly 5,000 patients enrolled in GRADE were an average age of 57 years old, 64% were men, 66% were White, and 20% were Black. They had had type 2 diabetes, on average, for 4.2 years. Mean body mass index at entry was about 34 kg/m2, average A1c was 7.5%, and average estimated glomerular filtration rate was 95 mL/min/1.73m2. The trial included a 6-12 week run-in period during which background metformin treatment was optimized and led to average A1c levels less than 7%.
Patients were then randomized to one of the four agents as add-on treatment.
Both liraglutide and insulin glargine performed well on many of the numerous metrics in the data-rich trial, largely funded by two branches of the National Institutes of Health, with commercial involvement limited to free supplies of the study drugs.
The secondary metabolic outcome, of disease progressing to a confirmed A1c of 7.5%, was reached by 39% of patients taking insulin glargine, significantly lower than the rate of 46% among patients taking liraglutide, and that rate, in turn, was significantly below the 50% rate among patients taking glimepiride and the 55% rate of those taking sitagliptin.
Mean doses of the second-line agents after 4 years of treatment were 38.3 units/day for glargine, 3.5 mg/day for glimepiride, 1.3 mg/day for subcutaneous liraglutide, and 82.9 mg/day for sitagliptin.
A trio of cardiovascular outcomes showed one significant benefit of liraglutide over the other three drugs for the endpoint of any cardiovascular event, which included not only major adverse cardiovascular events (MACE; cardiovascular death, myocardial infarction, or stroke), but also several other event types, including heart failure requiring hospitalization, unstable angina requiring hospitalization, revascularization or any arterial repairs, stent thrombosis, or transient ischemic attack.
For the endpoint of any cardiovascular event, the rate was 5.8% for patients taking liraglutide, significantly less than the rate of 7.6% of those taking insulin glargine, 8.0% for glimepiride, and 8.6% for sitagliptin, reported John B. Buse, MD, PhD, professor, chief of endocrinology, and director of the Diabetes Center at the University of North Carolina at Chapel Hill.
For each of the other two main cardiovascular endpoints – MACE and hospitalization for heart failure – liraglutide had a numeric advantage over the other three drugs but failed to reach significance.
Patients taking liraglutide also had a smaller but not significantly different point estimate for all-cause death, at 2.1%, compared with 3.1%-3.4% in the other three groups.
And, Dr. Nathan emphasized, the cardiovascular disease data are still considered preliminary.
Liraglutide scored a pair of additional outcome victories. Its use resulted in a significantly lower rate of patients who progressed during follow-up to either needing antihypertensive medications or having their blood pressure rise above 140/90 mm Hg compared with the other three drugs. (At baseline, average blood pressure for all patients was 128/77 mm Hg.)
And after 4 years, patients taking liraglutide lost an average of about 4 kg (8.8 lb) from their baseline weight (which averaged about 100 kg [220 lb]), roughly the same as patients taking sitagliptin but significantly better than with glimepiride or insulin glargine. Patients taking glargine gained a small amount of weight on average during their first couple of years of treatment, roughly 1 kg, but returned to around their baseline weight by the end of 4 years.
Four drugs performed equally well for some outcomes
Finally, the four drugs had similar results for some outcomes. This included their effects on renal function, distal sensory polyneuropathy, and low-density lipoprotein (LDL) cholesterol.
The four agents also had roughly similar safety profiles, with rates of serious adverse events all falling within the tight range of 33%-37%.
But the rate of severe hypoglycemic episodes that required assistance to treat showed significant separation, ranging from 2.3% for glimepiride, 1.4% for glargine, 0.9% for liraglutide, and 0.7% for sitagliptin. Gastrointestinal symptoms occurred in about 50% of patients in three of the treatment groups but were significantly higher in those taking liraglutide, affecting 60%.
GRADE received no commercial funding. Dr. Wexler has reported serving on data monitoring committees for Novo Nordisk. Dr. Buse has reported being a consultant for and holding stock in numerous companies. Dr. Rosenstock has reported being an advisor or consultant to Applied Therapeutics, Boehringer Ingelheim, Hanmi Pharmaceutical, Intarcia Therapeutics, Lilly, Novo Nordisk, Oramed, and Sanofi and has received research support from numerous companies. Dr. Kahn has reported being an advisor to or speaker on behalf of Bayer, Boehringer Ingelheim, Casma Therapeutics, Intarcia Therapeutics, Lilly, Merck, Novo Nordisk, Pfizer, and Third Rock Ventures. Dr. Matthews has reported receiving lecture and advisor fees from Merck, Novartis, Novo Nordisk, Sanofi Aventis, and Servier. Dr. Lachin and Dr. Nathan have reported no relevant financial relationships.
A version of this article first appeared on Medscape.com.
Magnesium is strongly tied to lower risk for intracranial aneurysm
The effects may be partially mediated by magnesium’s influence on systolic blood pressure, new research suggests.
“The modifiable risk factors for intracranial aneurysm are largely unknown. Our findings provided evidence of a causal association between increased serum magnesium levels and reduced risk of intracranial aneurysm,” said Susanna Larsson, PhD, Karolinska Institutet, Stockholm.
These results suggest that raising serum magnesium levels – through a magnesium-rich diet or magnesium supplementation – “may play a role in the primary prevention of intracranial aneurysm and associated hemorrhage,” Dr. Larsson added.
The study was published online June 22 in Neurology.
Lower risk for rupture
The researchers leveraged randomly allocated genetic variants related to serum magnesium concentrations in a two-sample Mendelian randomization (MR) study to assess whether higher genetically predicted serum magnesium correlates with reduced risk for intracranial aneurysm. They also performed a multivariable MR analysis to assess the role blood pressure might play in this association.
Source data came from a genome-wide association study (GWAS) involving 23,829 individuals that previously identified five single-nucleotide polymorphisms associated with serum magnesium. Genetic association estimates for intracranial aneurysm were derived from a GWAS in 79,429 people (7,495 case patients and 71,934 control patients), and genetic association estimates for systolic blood pressure were derived from a GWAS of 757,601 individuals.
The researchers found that higher genetically predicted serum magnesium concentrations were associated with lower risk for intracranial aneurysm.
The odds ratios per 0.1 mmol/L increment in genetically predicted serum magnesium concentrations were 0.66 (95% confidence interval, 0.49-0.91) for intracranial aneurysm (unruptured and ruptured combined), 0.57 (95% CI, 0.30-1.06) for unruptured intracranial aneurysm, and 0.67 (95% CI, 0.48-0.92) for aneurysmal subarachnoid hemorrhage.
Adjustment for genetically predicted systolic blood pressure partially attenuated the associations of genetically predicted serum magnesium with all three outcomes, suggesting that magnesium’s influence was at least partially mediated by systolic blood pressure.
“In addition to a blood pressure lowering effect, increased magnesium concentrations may reduce the risk of intracranial aneurysm rupture by improving endothelial function and reducing oxidative stress,” the investigators noted.
They caution that the data were derived from people of European ancestry, which limits the generalizability to other populations. “Caution should be taken when extrapolating findings from MR to infer the effect of a clinical intervention, and clinical trials are warranted to guide optimal practice,” they added.
Critical role in vascular health
In an accompanying editorial, Joanna Pera, MD, PhD, of Jagiellonian University Medical College, Krakow, Poland, and Christopher Anderson, MD, of Brigham and Women’s Hospital, Boston, noted that the study “adds to our understanding of the importance of magnesium in vascular health particularly related to cerebral aneurysms.”
There is a need for “both mechanistic and potentially therapeutic investigation into the role that magnesium plays in subarachnoid hemorrhage,” they added.
Further, they wrote, the results “raise interesting new questions about the links between circulating magnesium, intracranial aneurysms, and blood pressure. Arterial hypertension is a well-recognized risk factor for intracranial aneurysm development and rupture. Magnesium supplementation may lower blood pressure values.
“Could this mineral prove useful in developing interventions that could prevent intracranial aneurysm development and/or rupture over and above a simple lowering of blood pressure, perhaps through pleiotropic effects on endothelial function or other mechanisms? With these results in hand, work is clearly needed to learn more about the biology of magnesium in the vascular system and in intracranial aneurysm biology in particular,” Dr. Pera and Dr. Anderson concluded.
This study was supported by the Swedish Research Council for Health, Working Life and Welfare, the British Heart Foundation Research Center of Excellence at Imperial College London, and the National Institute for Health Research Clinical Lectureship at St. George’s, University of London. Dr. Larsson has disclosed no relevant financial relationships. Study coauthor Dipender Gill, PhD, is employed part time by Novo Nordisk. Dr. Pera has disclosed no relevant financial relationships. Dr. Anderson has received research support from the Bayer AG and has consulted for ApoPharma and Invitae.
A version of this article first appeared on Medscape.com.
The effects may be partially mediated by magnesium’s influence on systolic blood pressure, new research suggests.
“The modifiable risk factors for intracranial aneurysm are largely unknown. Our findings provided evidence of a causal association between increased serum magnesium levels and reduced risk of intracranial aneurysm,” said Susanna Larsson, PhD, Karolinska Institutet, Stockholm.
These results suggest that raising serum magnesium levels – through a magnesium-rich diet or magnesium supplementation – “may play a role in the primary prevention of intracranial aneurysm and associated hemorrhage,” Dr. Larsson added.
The study was published online June 22 in Neurology.
Lower risk for rupture
The researchers leveraged randomly allocated genetic variants related to serum magnesium concentrations in a two-sample Mendelian randomization (MR) study to assess whether higher genetically predicted serum magnesium correlates with reduced risk for intracranial aneurysm. They also performed a multivariable MR analysis to assess the role blood pressure might play in this association.
Source data came from a genome-wide association study (GWAS) involving 23,829 individuals that previously identified five single-nucleotide polymorphisms associated with serum magnesium. Genetic association estimates for intracranial aneurysm were derived from a GWAS in 79,429 people (7,495 case patients and 71,934 control patients), and genetic association estimates for systolic blood pressure were derived from a GWAS of 757,601 individuals.
The researchers found that higher genetically predicted serum magnesium concentrations were associated with lower risk for intracranial aneurysm.
The odds ratios per 0.1 mmol/L increment in genetically predicted serum magnesium concentrations were 0.66 (95% confidence interval, 0.49-0.91) for intracranial aneurysm (unruptured and ruptured combined), 0.57 (95% CI, 0.30-1.06) for unruptured intracranial aneurysm, and 0.67 (95% CI, 0.48-0.92) for aneurysmal subarachnoid hemorrhage.
Adjustment for genetically predicted systolic blood pressure partially attenuated the associations of genetically predicted serum magnesium with all three outcomes, suggesting that magnesium’s influence was at least partially mediated by systolic blood pressure.
“In addition to a blood pressure lowering effect, increased magnesium concentrations may reduce the risk of intracranial aneurysm rupture by improving endothelial function and reducing oxidative stress,” the investigators noted.
They caution that the data were derived from people of European ancestry, which limits the generalizability to other populations. “Caution should be taken when extrapolating findings from MR to infer the effect of a clinical intervention, and clinical trials are warranted to guide optimal practice,” they added.
Critical role in vascular health
In an accompanying editorial, Joanna Pera, MD, PhD, of Jagiellonian University Medical College, Krakow, Poland, and Christopher Anderson, MD, of Brigham and Women’s Hospital, Boston, noted that the study “adds to our understanding of the importance of magnesium in vascular health particularly related to cerebral aneurysms.”
There is a need for “both mechanistic and potentially therapeutic investigation into the role that magnesium plays in subarachnoid hemorrhage,” they added.
Further, they wrote, the results “raise interesting new questions about the links between circulating magnesium, intracranial aneurysms, and blood pressure. Arterial hypertension is a well-recognized risk factor for intracranial aneurysm development and rupture. Magnesium supplementation may lower blood pressure values.
“Could this mineral prove useful in developing interventions that could prevent intracranial aneurysm development and/or rupture over and above a simple lowering of blood pressure, perhaps through pleiotropic effects on endothelial function or other mechanisms? With these results in hand, work is clearly needed to learn more about the biology of magnesium in the vascular system and in intracranial aneurysm biology in particular,” Dr. Pera and Dr. Anderson concluded.
This study was supported by the Swedish Research Council for Health, Working Life and Welfare, the British Heart Foundation Research Center of Excellence at Imperial College London, and the National Institute for Health Research Clinical Lectureship at St. George’s, University of London. Dr. Larsson has disclosed no relevant financial relationships. Study coauthor Dipender Gill, PhD, is employed part time by Novo Nordisk. Dr. Pera has disclosed no relevant financial relationships. Dr. Anderson has received research support from the Bayer AG and has consulted for ApoPharma and Invitae.
A version of this article first appeared on Medscape.com.
The effects may be partially mediated by magnesium’s influence on systolic blood pressure, new research suggests.
“The modifiable risk factors for intracranial aneurysm are largely unknown. Our findings provided evidence of a causal association between increased serum magnesium levels and reduced risk of intracranial aneurysm,” said Susanna Larsson, PhD, Karolinska Institutet, Stockholm.
These results suggest that raising serum magnesium levels – through a magnesium-rich diet or magnesium supplementation – “may play a role in the primary prevention of intracranial aneurysm and associated hemorrhage,” Dr. Larsson added.
The study was published online June 22 in Neurology.
Lower risk for rupture
The researchers leveraged randomly allocated genetic variants related to serum magnesium concentrations in a two-sample Mendelian randomization (MR) study to assess whether higher genetically predicted serum magnesium correlates with reduced risk for intracranial aneurysm. They also performed a multivariable MR analysis to assess the role blood pressure might play in this association.
Source data came from a genome-wide association study (GWAS) involving 23,829 individuals that previously identified five single-nucleotide polymorphisms associated with serum magnesium. Genetic association estimates for intracranial aneurysm were derived from a GWAS in 79,429 people (7,495 case patients and 71,934 control patients), and genetic association estimates for systolic blood pressure were derived from a GWAS of 757,601 individuals.
The researchers found that higher genetically predicted serum magnesium concentrations were associated with lower risk for intracranial aneurysm.
The odds ratios per 0.1 mmol/L increment in genetically predicted serum magnesium concentrations were 0.66 (95% confidence interval, 0.49-0.91) for intracranial aneurysm (unruptured and ruptured combined), 0.57 (95% CI, 0.30-1.06) for unruptured intracranial aneurysm, and 0.67 (95% CI, 0.48-0.92) for aneurysmal subarachnoid hemorrhage.
Adjustment for genetically predicted systolic blood pressure partially attenuated the associations of genetically predicted serum magnesium with all three outcomes, suggesting that magnesium’s influence was at least partially mediated by systolic blood pressure.
“In addition to a blood pressure lowering effect, increased magnesium concentrations may reduce the risk of intracranial aneurysm rupture by improving endothelial function and reducing oxidative stress,” the investigators noted.
They caution that the data were derived from people of European ancestry, which limits the generalizability to other populations. “Caution should be taken when extrapolating findings from MR to infer the effect of a clinical intervention, and clinical trials are warranted to guide optimal practice,” they added.
Critical role in vascular health
In an accompanying editorial, Joanna Pera, MD, PhD, of Jagiellonian University Medical College, Krakow, Poland, and Christopher Anderson, MD, of Brigham and Women’s Hospital, Boston, noted that the study “adds to our understanding of the importance of magnesium in vascular health particularly related to cerebral aneurysms.”
There is a need for “both mechanistic and potentially therapeutic investigation into the role that magnesium plays in subarachnoid hemorrhage,” they added.
Further, they wrote, the results “raise interesting new questions about the links between circulating magnesium, intracranial aneurysms, and blood pressure. Arterial hypertension is a well-recognized risk factor for intracranial aneurysm development and rupture. Magnesium supplementation may lower blood pressure values.
“Could this mineral prove useful in developing interventions that could prevent intracranial aneurysm development and/or rupture over and above a simple lowering of blood pressure, perhaps through pleiotropic effects on endothelial function or other mechanisms? With these results in hand, work is clearly needed to learn more about the biology of magnesium in the vascular system and in intracranial aneurysm biology in particular,” Dr. Pera and Dr. Anderson concluded.
This study was supported by the Swedish Research Council for Health, Working Life and Welfare, the British Heart Foundation Research Center of Excellence at Imperial College London, and the National Institute for Health Research Clinical Lectureship at St. George’s, University of London. Dr. Larsson has disclosed no relevant financial relationships. Study coauthor Dipender Gill, PhD, is employed part time by Novo Nordisk. Dr. Pera has disclosed no relevant financial relationships. Dr. Anderson has received research support from the Bayer AG and has consulted for ApoPharma and Invitae.
A version of this article first appeared on Medscape.com.
From Neurology
Stroke risk in new-onset atrial fib goes up with greater alcohol intake
There’s abundant evidence linking higher alcohol intake levels to greater stroke risk and, separately, increasing risk for new-onset atrial fibrillation (AFib). Less settled is whether moderate to heavy drinking worsens the risk for stroke in patients already in AFib and whether giving up alcohol can attenuate that risk. A new observational study suggests the answer to both questions is yes.
The risk for ischemic stroke was only around 1% over about 5 years in a Korean nationwide cohort of almost 98,000 patients with new-onset AFib. About half the patients followed were nondrinkers, as they had been before the study, 13% became abstinent soon after their AFib diagnosis, and 36% were currently drinkers.
But stroke risk went up about 30% with “moderate” current alcohol intake, compared with no intake, and by more than 40% for current drinkers reporting “heavy” alcohol intake, researchers found in an adjusted analysis.
However, abstainers who had mild to moderate alcohol-intake levels before their AFib diagnosis “had a similar risk of ischemic stroke as nondrinkers,” write the authors, led by So-Ryoung Lee, MD, PhD, and colleagues, Seoul National University Hospital, Republic of Korea, in their report published June 7 in the European Heart Journal. In a secondary analysis, binge drinking was also independently associated with risk for ischemic stroke.
The findings suggest that “alcohol abstinence after the diagnosis of AFib could reduce the risk of ischemic stroke,” they conclude. “Lifestyle interventions, including attention to alcohol consumption, should be encouraged as part of a comprehensive approach in the management of patients with a new diagnosis of AFib” for lowering the risk for stroke and other clinical outcomes.
“These results are pretty comparable to those obtained in the more general population,” David Conen, MD, MPH, not connected to the analysis, told this news organization.
In the study’s population with new-onset AFib, there is an alcohol-dependent risk for stroke “that goes up with increasing alcohol intake, which is more or less similar to that found without atrial fibrillation in previous studies,” said Dr. Conen, from the Population Health Research Institute, McMaster University, Hamilton, Ont.
The study, “which overall I think is very well done,” he said, is noteworthy for also suggesting that binge drinking, which was scrutinized in a secondary analysis, appeared independently to worsen the risk for stroke in its AFib population.
Dr. Conen said the observed 1% overall risk for stroke was very similar to the rate he and his colleagues saw in a recent combined analysis of two European cohorts with AFib that was usually longer standing; the median was 3 years. That analysis, in contrast, showed no significant association between increasing levels of alcohol intake and risk for stroke or systemic embolism.
However, “our confidence limits did not exclude the possibility of a small to moderate association,” he said. Given that, and the current study from Korea, there might indeed be “a weak association between alcohol consumption and stroke” in patients with AFib.
“Their results are just more precise because of the larger sample size. That’s why they were able to show those associations,” said Dr. Conen, who was senior author on the earlier report, which covered a pooled analysis of 3,852 patients with AFib in the BEAT-AF and SWISS-AF cohort studies. It was published January 25 in CMAJ, with lead author Philipp Reddiess, MD, Cardiovascular Research Institute Basel, Switzerland.
The two published studies contrast in other ways that are worth noting and together suggest the stroke rate might have been 1% in both by chance, Dr. Conen said. “The populations were pretty different.”
In the earlier study, for example, the overwhelmingly European patients had more comorbidities and had been in AFib for much longer; their mean age was 71 years; and 84% were on oral anticoagulation (OAC).
In contrast, the Korean cohort averaged 61 years in age and only about 24% were taking oral anticoagulants. Given their distribution of CHA2DS2-VASc scores and mean score of 2.3, more than twice as many should have been on OAC, Dr. Conen speculated. “Even if you take into account that some patients may have contraindications, this is clearly an underanticoagulated population.”
The European cohort might have been “a little bit more representative because atrial fibrillation is a disease of the elderly,” Dr. Conen said, but “the Korean paper has the advantage of being a population-based study.”
It involved 97,869 patients from a Korean national data base who were newly diagnosed with AFib from 2010 to 2016. Of the total, 49,781 (51%) were continuously nondrinkers before and after their diagnosis; 12,789 (13%) abstained from alcohol only after their AFib diagnosis; and 35,299 (36%) were drinkers during the follow-up, either because they continued to drink or newly started after their diagnosis.
Of the cohort, 3,120 were diagnosed with new ischemic stroke over a follow-up of 310,926 person-years, for a rate of 1 per 100 person-years.
The adjusted hazard ratio (HR) for ischemic stroke over a 5-year follow-up, compared with nondrinkers, was:
- 1.127 (95% confidence interval, 1.003-1.266) among abstainers
- 1.280 (95% CI, 1.166-1.405) for current drinkers
The corresponding HR, compared with current drinkers, was:
- 0.781 (95% CI, 0.712-0.858) for nondrinkers
- 0.880 (95% CI, 0.782-0.990) among abstainers
No significant interactions with ischemic stroke risk were observed in groups by sex, age, CHA2DS2-VASc score, or smoking status. The risk rose consistently with current drinking levels.
The overall stroke rate of 1% per year is “very low,” and “the absolute differences are small, even though there is a clear significant trend from nondrinking to drinking,” Dr. Conen said.
However, “the difference becomes more sizable when you compare heavy drinking to abstinence.”
Dr. Lee reports no conflicts of interest; disclosures for the other authors are in their report. Dr. Conen reports receiving speaker fees from Servier Canada; disclosures for the other authors are in their report.
A version of this article first appeared on Medscape.com.
There’s abundant evidence linking higher alcohol intake levels to greater stroke risk and, separately, increasing risk for new-onset atrial fibrillation (AFib). Less settled is whether moderate to heavy drinking worsens the risk for stroke in patients already in AFib and whether giving up alcohol can attenuate that risk. A new observational study suggests the answer to both questions is yes.
The risk for ischemic stroke was only around 1% over about 5 years in a Korean nationwide cohort of almost 98,000 patients with new-onset AFib. About half the patients followed were nondrinkers, as they had been before the study, 13% became abstinent soon after their AFib diagnosis, and 36% were currently drinkers.
But stroke risk went up about 30% with “moderate” current alcohol intake, compared with no intake, and by more than 40% for current drinkers reporting “heavy” alcohol intake, researchers found in an adjusted analysis.
However, abstainers who had mild to moderate alcohol-intake levels before their AFib diagnosis “had a similar risk of ischemic stroke as nondrinkers,” write the authors, led by So-Ryoung Lee, MD, PhD, and colleagues, Seoul National University Hospital, Republic of Korea, in their report published June 7 in the European Heart Journal. In a secondary analysis, binge drinking was also independently associated with risk for ischemic stroke.
The findings suggest that “alcohol abstinence after the diagnosis of AFib could reduce the risk of ischemic stroke,” they conclude. “Lifestyle interventions, including attention to alcohol consumption, should be encouraged as part of a comprehensive approach in the management of patients with a new diagnosis of AFib” for lowering the risk for stroke and other clinical outcomes.
“These results are pretty comparable to those obtained in the more general population,” David Conen, MD, MPH, not connected to the analysis, told this news organization.
In the study’s population with new-onset AFib, there is an alcohol-dependent risk for stroke “that goes up with increasing alcohol intake, which is more or less similar to that found without atrial fibrillation in previous studies,” said Dr. Conen, from the Population Health Research Institute, McMaster University, Hamilton, Ont.
The study, “which overall I think is very well done,” he said, is noteworthy for also suggesting that binge drinking, which was scrutinized in a secondary analysis, appeared independently to worsen the risk for stroke in its AFib population.
Dr. Conen said the observed 1% overall risk for stroke was very similar to the rate he and his colleagues saw in a recent combined analysis of two European cohorts with AFib that was usually longer standing; the median was 3 years. That analysis, in contrast, showed no significant association between increasing levels of alcohol intake and risk for stroke or systemic embolism.
However, “our confidence limits did not exclude the possibility of a small to moderate association,” he said. Given that, and the current study from Korea, there might indeed be “a weak association between alcohol consumption and stroke” in patients with AFib.
“Their results are just more precise because of the larger sample size. That’s why they were able to show those associations,” said Dr. Conen, who was senior author on the earlier report, which covered a pooled analysis of 3,852 patients with AFib in the BEAT-AF and SWISS-AF cohort studies. It was published January 25 in CMAJ, with lead author Philipp Reddiess, MD, Cardiovascular Research Institute Basel, Switzerland.
The two published studies contrast in other ways that are worth noting and together suggest the stroke rate might have been 1% in both by chance, Dr. Conen said. “The populations were pretty different.”
In the earlier study, for example, the overwhelmingly European patients had more comorbidities and had been in AFib for much longer; their mean age was 71 years; and 84% were on oral anticoagulation (OAC).
In contrast, the Korean cohort averaged 61 years in age and only about 24% were taking oral anticoagulants. Given their distribution of CHA2DS2-VASc scores and mean score of 2.3, more than twice as many should have been on OAC, Dr. Conen speculated. “Even if you take into account that some patients may have contraindications, this is clearly an underanticoagulated population.”
The European cohort might have been “a little bit more representative because atrial fibrillation is a disease of the elderly,” Dr. Conen said, but “the Korean paper has the advantage of being a population-based study.”
It involved 97,869 patients from a Korean national data base who were newly diagnosed with AFib from 2010 to 2016. Of the total, 49,781 (51%) were continuously nondrinkers before and after their diagnosis; 12,789 (13%) abstained from alcohol only after their AFib diagnosis; and 35,299 (36%) were drinkers during the follow-up, either because they continued to drink or newly started after their diagnosis.
Of the cohort, 3,120 were diagnosed with new ischemic stroke over a follow-up of 310,926 person-years, for a rate of 1 per 100 person-years.
The adjusted hazard ratio (HR) for ischemic stroke over a 5-year follow-up, compared with nondrinkers, was:
- 1.127 (95% confidence interval, 1.003-1.266) among abstainers
- 1.280 (95% CI, 1.166-1.405) for current drinkers
The corresponding HR, compared with current drinkers, was:
- 0.781 (95% CI, 0.712-0.858) for nondrinkers
- 0.880 (95% CI, 0.782-0.990) among abstainers
No significant interactions with ischemic stroke risk were observed in groups by sex, age, CHA2DS2-VASc score, or smoking status. The risk rose consistently with current drinking levels.
The overall stroke rate of 1% per year is “very low,” and “the absolute differences are small, even though there is a clear significant trend from nondrinking to drinking,” Dr. Conen said.
However, “the difference becomes more sizable when you compare heavy drinking to abstinence.”
Dr. Lee reports no conflicts of interest; disclosures for the other authors are in their report. Dr. Conen reports receiving speaker fees from Servier Canada; disclosures for the other authors are in their report.
A version of this article first appeared on Medscape.com.
There’s abundant evidence linking higher alcohol intake levels to greater stroke risk and, separately, increasing risk for new-onset atrial fibrillation (AFib). Less settled is whether moderate to heavy drinking worsens the risk for stroke in patients already in AFib and whether giving up alcohol can attenuate that risk. A new observational study suggests the answer to both questions is yes.
The risk for ischemic stroke was only around 1% over about 5 years in a Korean nationwide cohort of almost 98,000 patients with new-onset AFib. About half the patients followed were nondrinkers, as they had been before the study, 13% became abstinent soon after their AFib diagnosis, and 36% were currently drinkers.
But stroke risk went up about 30% with “moderate” current alcohol intake, compared with no intake, and by more than 40% for current drinkers reporting “heavy” alcohol intake, researchers found in an adjusted analysis.
However, abstainers who had mild to moderate alcohol-intake levels before their AFib diagnosis “had a similar risk of ischemic stroke as nondrinkers,” write the authors, led by So-Ryoung Lee, MD, PhD, and colleagues, Seoul National University Hospital, Republic of Korea, in their report published June 7 in the European Heart Journal. In a secondary analysis, binge drinking was also independently associated with risk for ischemic stroke.
The findings suggest that “alcohol abstinence after the diagnosis of AFib could reduce the risk of ischemic stroke,” they conclude. “Lifestyle interventions, including attention to alcohol consumption, should be encouraged as part of a comprehensive approach in the management of patients with a new diagnosis of AFib” for lowering the risk for stroke and other clinical outcomes.
“These results are pretty comparable to those obtained in the more general population,” David Conen, MD, MPH, not connected to the analysis, told this news organization.
In the study’s population with new-onset AFib, there is an alcohol-dependent risk for stroke “that goes up with increasing alcohol intake, which is more or less similar to that found without atrial fibrillation in previous studies,” said Dr. Conen, from the Population Health Research Institute, McMaster University, Hamilton, Ont.
The study, “which overall I think is very well done,” he said, is noteworthy for also suggesting that binge drinking, which was scrutinized in a secondary analysis, appeared independently to worsen the risk for stroke in its AFib population.
Dr. Conen said the observed 1% overall risk for stroke was very similar to the rate he and his colleagues saw in a recent combined analysis of two European cohorts with AFib that was usually longer standing; the median was 3 years. That analysis, in contrast, showed no significant association between increasing levels of alcohol intake and risk for stroke or systemic embolism.
However, “our confidence limits did not exclude the possibility of a small to moderate association,” he said. Given that, and the current study from Korea, there might indeed be “a weak association between alcohol consumption and stroke” in patients with AFib.
“Their results are just more precise because of the larger sample size. That’s why they were able to show those associations,” said Dr. Conen, who was senior author on the earlier report, which covered a pooled analysis of 3,852 patients with AFib in the BEAT-AF and SWISS-AF cohort studies. It was published January 25 in CMAJ, with lead author Philipp Reddiess, MD, Cardiovascular Research Institute Basel, Switzerland.
The two published studies contrast in other ways that are worth noting and together suggest the stroke rate might have been 1% in both by chance, Dr. Conen said. “The populations were pretty different.”
In the earlier study, for example, the overwhelmingly European patients had more comorbidities and had been in AFib for much longer; their mean age was 71 years; and 84% were on oral anticoagulation (OAC).
In contrast, the Korean cohort averaged 61 years in age and only about 24% were taking oral anticoagulants. Given their distribution of CHA2DS2-VASc scores and mean score of 2.3, more than twice as many should have been on OAC, Dr. Conen speculated. “Even if you take into account that some patients may have contraindications, this is clearly an underanticoagulated population.”
The European cohort might have been “a little bit more representative because atrial fibrillation is a disease of the elderly,” Dr. Conen said, but “the Korean paper has the advantage of being a population-based study.”
It involved 97,869 patients from a Korean national data base who were newly diagnosed with AFib from 2010 to 2016. Of the total, 49,781 (51%) were continuously nondrinkers before and after their diagnosis; 12,789 (13%) abstained from alcohol only after their AFib diagnosis; and 35,299 (36%) were drinkers during the follow-up, either because they continued to drink or newly started after their diagnosis.
Of the cohort, 3,120 were diagnosed with new ischemic stroke over a follow-up of 310,926 person-years, for a rate of 1 per 100 person-years.
The adjusted hazard ratio (HR) for ischemic stroke over a 5-year follow-up, compared with nondrinkers, was:
- 1.127 (95% confidence interval, 1.003-1.266) among abstainers
- 1.280 (95% CI, 1.166-1.405) for current drinkers
The corresponding HR, compared with current drinkers, was:
- 0.781 (95% CI, 0.712-0.858) for nondrinkers
- 0.880 (95% CI, 0.782-0.990) among abstainers
No significant interactions with ischemic stroke risk were observed in groups by sex, age, CHA2DS2-VASc score, or smoking status. The risk rose consistently with current drinking levels.
The overall stroke rate of 1% per year is “very low,” and “the absolute differences are small, even though there is a clear significant trend from nondrinking to drinking,” Dr. Conen said.
However, “the difference becomes more sizable when you compare heavy drinking to abstinence.”
Dr. Lee reports no conflicts of interest; disclosures for the other authors are in their report. Dr. Conen reports receiving speaker fees from Servier Canada; disclosures for the other authors are in their report.
A version of this article first appeared on Medscape.com.
Treating sleep apnea lowers MI and stroke risk
particularly for patients with moderate to severe OSA and those who are more adherent to CPAP therapy, a new study suggests.
“Most clinical trials on the effect of CPAP on CV diseases to date have focused on secondary CV prevention. This study contributes another piece of evidence about the role of CPAP therapy to prevent CV diseases,” said Diego R. Mazzotti, PhD, an assistant professor at the University of Kansas Medical Center, Kansas City.
“Our study, while observational, suggests that clinical trials focused on understanding how to sustain long-term CPAP adherence in obstructive sleep apnea patients are necessary and could be critical for optimizing comorbidity risk reduction,” Dr. Mazzotti said.
The study was presented at the virtual annual meeting of the Associated Professional Sleep Societies.
Good adherence important
The researchers analyzed the electronic health records of adults referred for a sleep study through the Kaiser Permanente Southern California health system. The sample included 11,145 adults without OSA, 13,898 with OSA who used CPAP, and 20,884 adults with OSA who did not use CPAP. None of them had CV disease at baseline. Median follow-up was 262 days.
The primary outcome was first occurrence of myocardial infarction, stroke, unstable angina, heart failure, or death caused by CV disease.
In adjusted models, adults with moderate to severe OSA (apnea-hypopnea index ≥15) who did not use CPAP were 71% more likely than those without OSA to have a first CV event (hazard ratio, 1.71; 95% CI, 1.11-2.64). However, the risk for a CV event during follow-up was 32% lower among OSA patients with any CPAP use (HR, 0.68; 95% CI, 0.50-0.93; P = .016).
The effect was mostly driven by those who used CPAP for at least 4 hours per night (HR, 0.60; 95% CI, 0.39-0.95). This association was stronger for those with moderate to severe OSA (HR, 0.56; 95% CI, 0.39-0.81).
“This study highlights the importance of long-term management of CPAP therapy in patients with moderate-severe OSA,” Dr. Mazzotti said in an interview.
“It suggests that maintaining good CPAP adherence might be beneficial for cardiovascular health, besides the already established benefits on quality of life, sleepiness, and other cardiometabolic functions,” he said.
Dr. Mazzotti said several mechanisms might explain the association between CPAP use and lower risk for CV events. “CPAP treats OSA by preventing respiratory pauses that occur during sleep, therefore preventing arousals, sleep fragmentation, and decreases in blood oxygen. These improved cardiorespiratory functions can be beneficial to avoid certain molecular changes that are known to contribute to cardiovascular risk, such as oxidative stress and inflammation,” he explained.
“However, specific studies fully understanding these mechanisms are necessary,” Dr. Mazzotti added.
In a comment, Nitun Verma, MD, a spokesperson for the American Academy of Sleep Medicine, said that “the frequent decreases in oxygen levels and fragmented sleep from apnea are associated with cardiovascular disorders. We know this from multiple studies. This, however, was a large study and strengthens the association between improving apnea and reduced serious cardiovascular events.”
Funding for the study was provided by the American Academy of Sleep Medicine Foundation and the American Heart Association. Dr. Mazzotti and Dr. Verma disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.
particularly for patients with moderate to severe OSA and those who are more adherent to CPAP therapy, a new study suggests.
“Most clinical trials on the effect of CPAP on CV diseases to date have focused on secondary CV prevention. This study contributes another piece of evidence about the role of CPAP therapy to prevent CV diseases,” said Diego R. Mazzotti, PhD, an assistant professor at the University of Kansas Medical Center, Kansas City.
“Our study, while observational, suggests that clinical trials focused on understanding how to sustain long-term CPAP adherence in obstructive sleep apnea patients are necessary and could be critical for optimizing comorbidity risk reduction,” Dr. Mazzotti said.
The study was presented at the virtual annual meeting of the Associated Professional Sleep Societies.
Good adherence important
The researchers analyzed the electronic health records of adults referred for a sleep study through the Kaiser Permanente Southern California health system. The sample included 11,145 adults without OSA, 13,898 with OSA who used CPAP, and 20,884 adults with OSA who did not use CPAP. None of them had CV disease at baseline. Median follow-up was 262 days.
The primary outcome was first occurrence of myocardial infarction, stroke, unstable angina, heart failure, or death caused by CV disease.
In adjusted models, adults with moderate to severe OSA (apnea-hypopnea index ≥15) who did not use CPAP were 71% more likely than those without OSA to have a first CV event (hazard ratio, 1.71; 95% CI, 1.11-2.64). However, the risk for a CV event during follow-up was 32% lower among OSA patients with any CPAP use (HR, 0.68; 95% CI, 0.50-0.93; P = .016).
The effect was mostly driven by those who used CPAP for at least 4 hours per night (HR, 0.60; 95% CI, 0.39-0.95). This association was stronger for those with moderate to severe OSA (HR, 0.56; 95% CI, 0.39-0.81).
“This study highlights the importance of long-term management of CPAP therapy in patients with moderate-severe OSA,” Dr. Mazzotti said in an interview.
“It suggests that maintaining good CPAP adherence might be beneficial for cardiovascular health, besides the already established benefits on quality of life, sleepiness, and other cardiometabolic functions,” he said.
Dr. Mazzotti said several mechanisms might explain the association between CPAP use and lower risk for CV events. “CPAP treats OSA by preventing respiratory pauses that occur during sleep, therefore preventing arousals, sleep fragmentation, and decreases in blood oxygen. These improved cardiorespiratory functions can be beneficial to avoid certain molecular changes that are known to contribute to cardiovascular risk, such as oxidative stress and inflammation,” he explained.
“However, specific studies fully understanding these mechanisms are necessary,” Dr. Mazzotti added.
In a comment, Nitun Verma, MD, a spokesperson for the American Academy of Sleep Medicine, said that “the frequent decreases in oxygen levels and fragmented sleep from apnea are associated with cardiovascular disorders. We know this from multiple studies. This, however, was a large study and strengthens the association between improving apnea and reduced serious cardiovascular events.”
Funding for the study was provided by the American Academy of Sleep Medicine Foundation and the American Heart Association. Dr. Mazzotti and Dr. Verma disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.
particularly for patients with moderate to severe OSA and those who are more adherent to CPAP therapy, a new study suggests.
“Most clinical trials on the effect of CPAP on CV diseases to date have focused on secondary CV prevention. This study contributes another piece of evidence about the role of CPAP therapy to prevent CV diseases,” said Diego R. Mazzotti, PhD, an assistant professor at the University of Kansas Medical Center, Kansas City.
“Our study, while observational, suggests that clinical trials focused on understanding how to sustain long-term CPAP adherence in obstructive sleep apnea patients are necessary and could be critical for optimizing comorbidity risk reduction,” Dr. Mazzotti said.
The study was presented at the virtual annual meeting of the Associated Professional Sleep Societies.
Good adherence important
The researchers analyzed the electronic health records of adults referred for a sleep study through the Kaiser Permanente Southern California health system. The sample included 11,145 adults without OSA, 13,898 with OSA who used CPAP, and 20,884 adults with OSA who did not use CPAP. None of them had CV disease at baseline. Median follow-up was 262 days.
The primary outcome was first occurrence of myocardial infarction, stroke, unstable angina, heart failure, or death caused by CV disease.
In adjusted models, adults with moderate to severe OSA (apnea-hypopnea index ≥15) who did not use CPAP were 71% more likely than those without OSA to have a first CV event (hazard ratio, 1.71; 95% CI, 1.11-2.64). However, the risk for a CV event during follow-up was 32% lower among OSA patients with any CPAP use (HR, 0.68; 95% CI, 0.50-0.93; P = .016).
The effect was mostly driven by those who used CPAP for at least 4 hours per night (HR, 0.60; 95% CI, 0.39-0.95). This association was stronger for those with moderate to severe OSA (HR, 0.56; 95% CI, 0.39-0.81).
“This study highlights the importance of long-term management of CPAP therapy in patients with moderate-severe OSA,” Dr. Mazzotti said in an interview.
“It suggests that maintaining good CPAP adherence might be beneficial for cardiovascular health, besides the already established benefits on quality of life, sleepiness, and other cardiometabolic functions,” he said.
Dr. Mazzotti said several mechanisms might explain the association between CPAP use and lower risk for CV events. “CPAP treats OSA by preventing respiratory pauses that occur during sleep, therefore preventing arousals, sleep fragmentation, and decreases in blood oxygen. These improved cardiorespiratory functions can be beneficial to avoid certain molecular changes that are known to contribute to cardiovascular risk, such as oxidative stress and inflammation,” he explained.
“However, specific studies fully understanding these mechanisms are necessary,” Dr. Mazzotti added.
In a comment, Nitun Verma, MD, a spokesperson for the American Academy of Sleep Medicine, said that “the frequent decreases in oxygen levels and fragmented sleep from apnea are associated with cardiovascular disorders. We know this from multiple studies. This, however, was a large study and strengthens the association between improving apnea and reduced serious cardiovascular events.”
Funding for the study was provided by the American Academy of Sleep Medicine Foundation and the American Heart Association. Dr. Mazzotti and Dr. Verma disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.
FROM SLEEP 2021
Bariatric surgery tied to 22% lower 5-year stroke risk
Patients with obesity who underwent bariatric surgery had 46% lower odds of stroke 1 year later, similar odds of stroke 3 years later, and 22% lower odds of stroke 5 years later, compared with matched control patients, in new research.
Michael D. Williams, MD, presented the study findings (abstract A002) at the annual meeting of the American Society for Metabolic & Bariatric Surgery.
The findings are “very good news,” even though the protection against stroke declined further out from the surgery, John D. Scott, MD, scientific program chair of the ASMBS meeting, told this news organization.
The investigators matched more than 56,000 patients with obesity who had bariatric surgery with an equal number of similar patients who did not have this surgery, from a large national insurance database, in what they believe is the largest study of this to date.
“Any intervention that decreases your risk of [cardiovascular] events is good news,” said Dr. Scott, a clinical professor of surgery at the University of South Carolina, Greenville, and metabolic and bariatric surgery director at Prisma Health in Greenville, S.C. “And having a 22%-45% chance of reduction in stroke risk is a very worthwhile intervention.”
Asked how this would change the way clinicians inform patients of what to expect from bariatric surgery, he said: “I would advise patients that studies like this show that surgery would not increase your risk of having a stroke.
“This is consistent with many studies that show that the risks of all macrovascular events decrease after the comorbidity reductions seen after surgery.”
According to Dr. Scott, “the next steps might include a prospective randomized trial of medical treatment versus surgery alone for [cardiovascular]/stroke outcomes, but this is unlikely.”
Similarly, Dr. Williams told this news organization that “I would tell [patients] that surgery is an effective and durable method for weight loss. It also can improve comorbid conditions, particularly diabetes and hypertension.”
Even with this study, “I’m not sure it’s appropriate to say that bariatric surgery will reduce the risk of stroke,” he cautioned.
“However, as we continue to investigate the effects of bariatric surgery, this study contributes to the greater body of knowledge that suggests that reduction in ischemic stroke risk is yet another benefit of bariatric surgery.”
The assigned discussant, Corrigan L. McBride, MD, MBA wanted to know if the lower odds ratio at 1 year might be because preoperative patient selection might eliminate patients at high risk of poor cardiovascular outcomes.
Dr. Williams, a resident at Rush Medical College, Chicago, replied that it is difficult to eliminate potential selection bias, despite best efforts, but this study shows that he can tell patients: “Having surgery is not going to increases your risk of stroke.”
“This is an important study,” Dr. McBride, professor and chief of minimally invasive surgery and bariatric surgery, University of Nebraska Medical Center, Omaha, told this news organization.
“It is the first large study to show a decreased [or no increased] risk of stroke 1, 3, and 5 years after bariatric surgery compared to matched patients, and it had enough data to look at stroke as a standalone endpoint,” Dr. McBride said. “It is important too, for patients and their physicians to understand that there is a lower chance of them having a stroke if they have surgery than if they do not.”
‘Important,’ ‘good news’ for stroke risk after bariatric surgery
The impact of bariatric surgery on remission of type 2 diabetes is well known, Dr. Williams noted, and other studies have reported how bariatric surgery affects the risk of major adverse cardiovascular events – a composite of stroke, myocardial infarction, coronary artery disease, and all-cause death – including a study presented in the same meeting session.
However, a very large sample size is needed to be able to demonstrate the effect of bariatric surgery on stroke, since stroke is a rare event.
The researchers analyzed data from the Mariner (PearlDiver.) all-payer insurance national claims database of patients in the United States.
They matched 56,514 patients with a body mass index over 35 kg/m2 and comorbidities or a BMI of more than 40 who underwent sleeve gastrectomy or Roux-en-Y gastric bypass during 2010-2019 with 56,514 control patients who did not undergo bariatric surgery.
A year after bariatric surgery, patients in that group had a lower stroke rate than patients in the control group (0.6% vs. 1.2%), and they had close to 50% lower odds of having a stroke (odds ratio, 0.54; 95% CI, 0.47-0.61).
Three years after bariatric surgery, there were 44,948 patients in each group; the rate of stroke was 2.1% in the surgery group and 2.2% in the control group, and there was no significant difference in the odds of having a stroke (OR, 0.96; 95% CI, 0.91-1.00).
Five years after bariatric surgery, there were 27,619 patients in each group; the stroke rate was lower in the bariatric surgery group than in the control group (2.8% vs 3.6%), but reduced odds of stroke was not as great as after 1 year (OR, 0.78; 95% CI, 0.65-0.90).
Dr. Williams has no relevant financial disclosures. Dr. McBride and Dr. Scott disclosed that they are speakers/trainers/faculty advisers for Gore. Dr. Scott is also a consultant for C-SATS (part of Johnson & Johnson).
Patients with obesity who underwent bariatric surgery had 46% lower odds of stroke 1 year later, similar odds of stroke 3 years later, and 22% lower odds of stroke 5 years later, compared with matched control patients, in new research.
Michael D. Williams, MD, presented the study findings (abstract A002) at the annual meeting of the American Society for Metabolic & Bariatric Surgery.
The findings are “very good news,” even though the protection against stroke declined further out from the surgery, John D. Scott, MD, scientific program chair of the ASMBS meeting, told this news organization.
The investigators matched more than 56,000 patients with obesity who had bariatric surgery with an equal number of similar patients who did not have this surgery, from a large national insurance database, in what they believe is the largest study of this to date.
“Any intervention that decreases your risk of [cardiovascular] events is good news,” said Dr. Scott, a clinical professor of surgery at the University of South Carolina, Greenville, and metabolic and bariatric surgery director at Prisma Health in Greenville, S.C. “And having a 22%-45% chance of reduction in stroke risk is a very worthwhile intervention.”
Asked how this would change the way clinicians inform patients of what to expect from bariatric surgery, he said: “I would advise patients that studies like this show that surgery would not increase your risk of having a stroke.
“This is consistent with many studies that show that the risks of all macrovascular events decrease after the comorbidity reductions seen after surgery.”
According to Dr. Scott, “the next steps might include a prospective randomized trial of medical treatment versus surgery alone for [cardiovascular]/stroke outcomes, but this is unlikely.”
Similarly, Dr. Williams told this news organization that “I would tell [patients] that surgery is an effective and durable method for weight loss. It also can improve comorbid conditions, particularly diabetes and hypertension.”
Even with this study, “I’m not sure it’s appropriate to say that bariatric surgery will reduce the risk of stroke,” he cautioned.
“However, as we continue to investigate the effects of bariatric surgery, this study contributes to the greater body of knowledge that suggests that reduction in ischemic stroke risk is yet another benefit of bariatric surgery.”
The assigned discussant, Corrigan L. McBride, MD, MBA wanted to know if the lower odds ratio at 1 year might be because preoperative patient selection might eliminate patients at high risk of poor cardiovascular outcomes.
Dr. Williams, a resident at Rush Medical College, Chicago, replied that it is difficult to eliminate potential selection bias, despite best efforts, but this study shows that he can tell patients: “Having surgery is not going to increases your risk of stroke.”
“This is an important study,” Dr. McBride, professor and chief of minimally invasive surgery and bariatric surgery, University of Nebraska Medical Center, Omaha, told this news organization.
“It is the first large study to show a decreased [or no increased] risk of stroke 1, 3, and 5 years after bariatric surgery compared to matched patients, and it had enough data to look at stroke as a standalone endpoint,” Dr. McBride said. “It is important too, for patients and their physicians to understand that there is a lower chance of them having a stroke if they have surgery than if they do not.”
‘Important,’ ‘good news’ for stroke risk after bariatric surgery
The impact of bariatric surgery on remission of type 2 diabetes is well known, Dr. Williams noted, and other studies have reported how bariatric surgery affects the risk of major adverse cardiovascular events – a composite of stroke, myocardial infarction, coronary artery disease, and all-cause death – including a study presented in the same meeting session.
However, a very large sample size is needed to be able to demonstrate the effect of bariatric surgery on stroke, since stroke is a rare event.
The researchers analyzed data from the Mariner (PearlDiver.) all-payer insurance national claims database of patients in the United States.
They matched 56,514 patients with a body mass index over 35 kg/m2 and comorbidities or a BMI of more than 40 who underwent sleeve gastrectomy or Roux-en-Y gastric bypass during 2010-2019 with 56,514 control patients who did not undergo bariatric surgery.
A year after bariatric surgery, patients in that group had a lower stroke rate than patients in the control group (0.6% vs. 1.2%), and they had close to 50% lower odds of having a stroke (odds ratio, 0.54; 95% CI, 0.47-0.61).
Three years after bariatric surgery, there were 44,948 patients in each group; the rate of stroke was 2.1% in the surgery group and 2.2% in the control group, and there was no significant difference in the odds of having a stroke (OR, 0.96; 95% CI, 0.91-1.00).
Five years after bariatric surgery, there were 27,619 patients in each group; the stroke rate was lower in the bariatric surgery group than in the control group (2.8% vs 3.6%), but reduced odds of stroke was not as great as after 1 year (OR, 0.78; 95% CI, 0.65-0.90).
Dr. Williams has no relevant financial disclosures. Dr. McBride and Dr. Scott disclosed that they are speakers/trainers/faculty advisers for Gore. Dr. Scott is also a consultant for C-SATS (part of Johnson & Johnson).
Patients with obesity who underwent bariatric surgery had 46% lower odds of stroke 1 year later, similar odds of stroke 3 years later, and 22% lower odds of stroke 5 years later, compared with matched control patients, in new research.
Michael D. Williams, MD, presented the study findings (abstract A002) at the annual meeting of the American Society for Metabolic & Bariatric Surgery.
The findings are “very good news,” even though the protection against stroke declined further out from the surgery, John D. Scott, MD, scientific program chair of the ASMBS meeting, told this news organization.
The investigators matched more than 56,000 patients with obesity who had bariatric surgery with an equal number of similar patients who did not have this surgery, from a large national insurance database, in what they believe is the largest study of this to date.
“Any intervention that decreases your risk of [cardiovascular] events is good news,” said Dr. Scott, a clinical professor of surgery at the University of South Carolina, Greenville, and metabolic and bariatric surgery director at Prisma Health in Greenville, S.C. “And having a 22%-45% chance of reduction in stroke risk is a very worthwhile intervention.”
Asked how this would change the way clinicians inform patients of what to expect from bariatric surgery, he said: “I would advise patients that studies like this show that surgery would not increase your risk of having a stroke.
“This is consistent with many studies that show that the risks of all macrovascular events decrease after the comorbidity reductions seen after surgery.”
According to Dr. Scott, “the next steps might include a prospective randomized trial of medical treatment versus surgery alone for [cardiovascular]/stroke outcomes, but this is unlikely.”
Similarly, Dr. Williams told this news organization that “I would tell [patients] that surgery is an effective and durable method for weight loss. It also can improve comorbid conditions, particularly diabetes and hypertension.”
Even with this study, “I’m not sure it’s appropriate to say that bariatric surgery will reduce the risk of stroke,” he cautioned.
“However, as we continue to investigate the effects of bariatric surgery, this study contributes to the greater body of knowledge that suggests that reduction in ischemic stroke risk is yet another benefit of bariatric surgery.”
The assigned discussant, Corrigan L. McBride, MD, MBA wanted to know if the lower odds ratio at 1 year might be because preoperative patient selection might eliminate patients at high risk of poor cardiovascular outcomes.
Dr. Williams, a resident at Rush Medical College, Chicago, replied that it is difficult to eliminate potential selection bias, despite best efforts, but this study shows that he can tell patients: “Having surgery is not going to increases your risk of stroke.”
“This is an important study,” Dr. McBride, professor and chief of minimally invasive surgery and bariatric surgery, University of Nebraska Medical Center, Omaha, told this news organization.
“It is the first large study to show a decreased [or no increased] risk of stroke 1, 3, and 5 years after bariatric surgery compared to matched patients, and it had enough data to look at stroke as a standalone endpoint,” Dr. McBride said. “It is important too, for patients and their physicians to understand that there is a lower chance of them having a stroke if they have surgery than if they do not.”
‘Important,’ ‘good news’ for stroke risk after bariatric surgery
The impact of bariatric surgery on remission of type 2 diabetes is well known, Dr. Williams noted, and other studies have reported how bariatric surgery affects the risk of major adverse cardiovascular events – a composite of stroke, myocardial infarction, coronary artery disease, and all-cause death – including a study presented in the same meeting session.
However, a very large sample size is needed to be able to demonstrate the effect of bariatric surgery on stroke, since stroke is a rare event.
The researchers analyzed data from the Mariner (PearlDiver.) all-payer insurance national claims database of patients in the United States.
They matched 56,514 patients with a body mass index over 35 kg/m2 and comorbidities or a BMI of more than 40 who underwent sleeve gastrectomy or Roux-en-Y gastric bypass during 2010-2019 with 56,514 control patients who did not undergo bariatric surgery.
A year after bariatric surgery, patients in that group had a lower stroke rate than patients in the control group (0.6% vs. 1.2%), and they had close to 50% lower odds of having a stroke (odds ratio, 0.54; 95% CI, 0.47-0.61).
Three years after bariatric surgery, there were 44,948 patients in each group; the rate of stroke was 2.1% in the surgery group and 2.2% in the control group, and there was no significant difference in the odds of having a stroke (OR, 0.96; 95% CI, 0.91-1.00).
Five years after bariatric surgery, there were 27,619 patients in each group; the stroke rate was lower in the bariatric surgery group than in the control group (2.8% vs 3.6%), but reduced odds of stroke was not as great as after 1 year (OR, 0.78; 95% CI, 0.65-0.90).
Dr. Williams has no relevant financial disclosures. Dr. McBride and Dr. Scott disclosed that they are speakers/trainers/faculty advisers for Gore. Dr. Scott is also a consultant for C-SATS (part of Johnson & Johnson).
FROM ASMBS 2021
Reversal agents curb DOAC-related bleeding but deaths still high
Agents that reverse the effect of direct oral anticoagulants (DOACs) are highly effective in patients with severe bleeding, but mortality rates remain high despite their use, a meta-analysis shows.
Effective hemostasis was achieved in 78.5% of patients treated with a reversal agent, whereas failure to achieve hemostasis was associated with more than a threefold higher relative risk for death (relative risk, 3.63; 95% confidence interval, 2.56-5.16).
“This has implications in practice because it emphasizes the need for achieving effective hemostasis, if not with only one agent, trying other agents or treatment modalities, because it is a strong predictor of survival,” lead author Antonio Gómez-Outes, MD, PhD, said in an interview.
The bad news, he said, is that the mortality rate was still significant, at 17.7%, and approximately half of patients with DOAC-related severe intracranial bleeding survived with long-term moderate/severe disability.
“The lesson is to prevent these bleeding events because once they appear, even if you give an antidote, the outcome is poor, particularly for intracranial bleeding,” said Dr. Gómez-Outes, division of pharmacology and clinical drug evaluation, Spanish Agency for Medicines and Medical Devices, Madrid.
To put this in context, mortality rates were close to 50% after intracranial bleeding a decade ago when there were no antidotes or reversal agents, he observed. “So to some extent, patient care has improved, and the outcome has improved, but there is a long road to improve regarding disability.”
More than 100,000 DOAC-related major bleeding cases occur each year in the United States and European Union, Dr. Gómez-Outes said, and about half are severe enough to require hospitalization and potentially the use of a reversal agent. These include idarucizumab (Praxbind) for dabigatran reversal and prothombin complex concentrates (4CCC) or andexanet alpha (Andexxa) for reversal of direct factor Xa inhibitors like rivaroxaban, apixaban, and edoxaban.
As reported in the June 22 issue of the Journal of the American College of Cardiology, the meta-analysis comprised 4,735 patients (mean age, 77 years; 57% male) with severe DOAC-related bleeding who received 4PCC (n = 2,688), idarucizumab (n = 1,111), or andexanet (n = 936) in 60 studies between January 2010 and December 2020.
Atrial fibrillation (AFib) was the most common reason for use of a DOAC (82%), followed by venous thromboembolism (14%). Rivaroxaban was used in 36%, apixaban in 32%, dabigatran in 31%, and edoxaban in 1%.
The index bleeding event was intracranial hemorrhage (ICH) in 55%. Anticoagulation was restarted in 57% of patients an average of 11 days after admission.
Mortality rates were 20.2% in patients with ICH and 15.4% in those with extracranial bleeding. There were no differences in death rates by reversal agent used, type of study, risk for bias, or study sponsorship in meta-regression analysis.
Rebleeding occurred in 13.2% of patients; 82.0% of these events were described as an ICH, and 78.0% occurred after anticoagulation was restarted.
The overall rate of thromboembolism was 4.6%. The risk was particularly high with andexanet, at 10.7%, and relatively low with idarucizumab (3.8%) and 4PCC (4.3%), the authors note.
“Our meta-analysis suggests specific reversal with andexanet is not superior to unspecific reversal with 4PCC, and that’s good news because many centers, in many countries, have no access to specific antidotes that are more costly,” Dr. Gómez-Outes said. “4PCC is an effective and relatively safe drug, so it’s still a good option for these patients.”
Labeling for andexanet includes a warning for thromboembolic events, but in the absence of direct comparisons, the findings should be interpreted with caution, he added. Further insights are expected from an ongoing randomized trial of andexanet and standard of care in 900 patients who present with acute ICH less than 15 hours after taking an oral factor Xa inhibitor. The preliminary completion date is set for 2023.
“The meta-analysis raises awareness about the rates of mortality and thromboembolism after reversal agent administration, although understanding the implications of these data is challenging,” Christopher Granger, MD, and Sean P. Pokomey, MD, MBA, Duke University Medical Center, Durham, N.C., say in an accompanying editorial.
The fact that failure to achieve hemostasis was associated with death is expected and might be related to the way hemostasis was defined, rather than the actual failure of the hemostatic treatments, they suggest. “The prothrombotic effects of each agent, including andexanet, need to be better understood, as clinicians work toward including reversal agents into algorithms for bleeding management.”
Effective hemostasis was defined in the studies through various methods as: “Excellent/good” using the Sarode and ANNEXA-4 scales; “yes” in the International Society on Thrombosis and Hemostasis Scale; and with other scales and through clinical judgment.
Although the size of the meta-analysis dwarfs previous reviews, the editorialists and authors point out that 47 of the 60 studies were retrospective, only two had control groups, and 45 had a high risk for bias.
In general, there was also poor reporting of key clinical data, such as postbleeding anticoagulation management, and a limitation of the mortality analysis is that it was based in selected patients with effective hemostasis assessed within 48 hours, which may not capture early deaths, the authors note.
“The morbidity and mortality from ischemic strokes as a result of undertreatment of stroke prevention in patients with AFib continue to dwarf the bleeding related mortality among patients with AFib and on DOACs, and thus the number one priority is to treat nearly all patients with AFib with a DOAC,” Dr. Granger and Dr. Pokomey conclude. “The availability of reversal agents for DOACs should provide reassurance, with another tool in our armamentarium, to providers to prescribe OACs for stroke prevention.”
No funding/grant support was received to conduct the study. Coauthor Ramón Lecumberri has received personal fees from Boehringer Ingelheim and Bristol Myers Squibb outside the submitted work. All other authors report no relevant financial relationships. Dr. Granger has received research and consulting fees from Bristol Myers Squibb, Pfizer, Boehringer Ingelheim, Bayer, Janssen, Boston Scientific, Apple, AstraZeneca, Novartis, AbbVie, Biomed, CeleCor, GSK, Novartis, Medtronic, Merck, Novo Nordisk, Philips, Rho, and the U.S. Food and Drug Administration. Dr. Pokomey has received modest consulting support from Bristol Myers Squibb, Pfizer, Boston Scientific, Medtronic, Janssen, and Zoll; modest research support from Gilead, Boston Scientific, Bristol Myers Squibb, Pfizer, and Janssen; and significant research support from the FDA.
A version of this article first appeared on Medscape.com.
Agents that reverse the effect of direct oral anticoagulants (DOACs) are highly effective in patients with severe bleeding, but mortality rates remain high despite their use, a meta-analysis shows.
Effective hemostasis was achieved in 78.5% of patients treated with a reversal agent, whereas failure to achieve hemostasis was associated with more than a threefold higher relative risk for death (relative risk, 3.63; 95% confidence interval, 2.56-5.16).
“This has implications in practice because it emphasizes the need for achieving effective hemostasis, if not with only one agent, trying other agents or treatment modalities, because it is a strong predictor of survival,” lead author Antonio Gómez-Outes, MD, PhD, said in an interview.
The bad news, he said, is that the mortality rate was still significant, at 17.7%, and approximately half of patients with DOAC-related severe intracranial bleeding survived with long-term moderate/severe disability.
“The lesson is to prevent these bleeding events because once they appear, even if you give an antidote, the outcome is poor, particularly for intracranial bleeding,” said Dr. Gómez-Outes, division of pharmacology and clinical drug evaluation, Spanish Agency for Medicines and Medical Devices, Madrid.
To put this in context, mortality rates were close to 50% after intracranial bleeding a decade ago when there were no antidotes or reversal agents, he observed. “So to some extent, patient care has improved, and the outcome has improved, but there is a long road to improve regarding disability.”
More than 100,000 DOAC-related major bleeding cases occur each year in the United States and European Union, Dr. Gómez-Outes said, and about half are severe enough to require hospitalization and potentially the use of a reversal agent. These include idarucizumab (Praxbind) for dabigatran reversal and prothombin complex concentrates (4CCC) or andexanet alpha (Andexxa) for reversal of direct factor Xa inhibitors like rivaroxaban, apixaban, and edoxaban.
As reported in the June 22 issue of the Journal of the American College of Cardiology, the meta-analysis comprised 4,735 patients (mean age, 77 years; 57% male) with severe DOAC-related bleeding who received 4PCC (n = 2,688), idarucizumab (n = 1,111), or andexanet (n = 936) in 60 studies between January 2010 and December 2020.
Atrial fibrillation (AFib) was the most common reason for use of a DOAC (82%), followed by venous thromboembolism (14%). Rivaroxaban was used in 36%, apixaban in 32%, dabigatran in 31%, and edoxaban in 1%.
The index bleeding event was intracranial hemorrhage (ICH) in 55%. Anticoagulation was restarted in 57% of patients an average of 11 days after admission.
Mortality rates were 20.2% in patients with ICH and 15.4% in those with extracranial bleeding. There were no differences in death rates by reversal agent used, type of study, risk for bias, or study sponsorship in meta-regression analysis.
Rebleeding occurred in 13.2% of patients; 82.0% of these events were described as an ICH, and 78.0% occurred after anticoagulation was restarted.
The overall rate of thromboembolism was 4.6%. The risk was particularly high with andexanet, at 10.7%, and relatively low with idarucizumab (3.8%) and 4PCC (4.3%), the authors note.
“Our meta-analysis suggests specific reversal with andexanet is not superior to unspecific reversal with 4PCC, and that’s good news because many centers, in many countries, have no access to specific antidotes that are more costly,” Dr. Gómez-Outes said. “4PCC is an effective and relatively safe drug, so it’s still a good option for these patients.”
Labeling for andexanet includes a warning for thromboembolic events, but in the absence of direct comparisons, the findings should be interpreted with caution, he added. Further insights are expected from an ongoing randomized trial of andexanet and standard of care in 900 patients who present with acute ICH less than 15 hours after taking an oral factor Xa inhibitor. The preliminary completion date is set for 2023.
“The meta-analysis raises awareness about the rates of mortality and thromboembolism after reversal agent administration, although understanding the implications of these data is challenging,” Christopher Granger, MD, and Sean P. Pokomey, MD, MBA, Duke University Medical Center, Durham, N.C., say in an accompanying editorial.
The fact that failure to achieve hemostasis was associated with death is expected and might be related to the way hemostasis was defined, rather than the actual failure of the hemostatic treatments, they suggest. “The prothrombotic effects of each agent, including andexanet, need to be better understood, as clinicians work toward including reversal agents into algorithms for bleeding management.”
Effective hemostasis was defined in the studies through various methods as: “Excellent/good” using the Sarode and ANNEXA-4 scales; “yes” in the International Society on Thrombosis and Hemostasis Scale; and with other scales and through clinical judgment.
Although the size of the meta-analysis dwarfs previous reviews, the editorialists and authors point out that 47 of the 60 studies were retrospective, only two had control groups, and 45 had a high risk for bias.
In general, there was also poor reporting of key clinical data, such as postbleeding anticoagulation management, and a limitation of the mortality analysis is that it was based in selected patients with effective hemostasis assessed within 48 hours, which may not capture early deaths, the authors note.
“The morbidity and mortality from ischemic strokes as a result of undertreatment of stroke prevention in patients with AFib continue to dwarf the bleeding related mortality among patients with AFib and on DOACs, and thus the number one priority is to treat nearly all patients with AFib with a DOAC,” Dr. Granger and Dr. Pokomey conclude. “The availability of reversal agents for DOACs should provide reassurance, with another tool in our armamentarium, to providers to prescribe OACs for stroke prevention.”
No funding/grant support was received to conduct the study. Coauthor Ramón Lecumberri has received personal fees from Boehringer Ingelheim and Bristol Myers Squibb outside the submitted work. All other authors report no relevant financial relationships. Dr. Granger has received research and consulting fees from Bristol Myers Squibb, Pfizer, Boehringer Ingelheim, Bayer, Janssen, Boston Scientific, Apple, AstraZeneca, Novartis, AbbVie, Biomed, CeleCor, GSK, Novartis, Medtronic, Merck, Novo Nordisk, Philips, Rho, and the U.S. Food and Drug Administration. Dr. Pokomey has received modest consulting support from Bristol Myers Squibb, Pfizer, Boston Scientific, Medtronic, Janssen, and Zoll; modest research support from Gilead, Boston Scientific, Bristol Myers Squibb, Pfizer, and Janssen; and significant research support from the FDA.
A version of this article first appeared on Medscape.com.
Agents that reverse the effect of direct oral anticoagulants (DOACs) are highly effective in patients with severe bleeding, but mortality rates remain high despite their use, a meta-analysis shows.
Effective hemostasis was achieved in 78.5% of patients treated with a reversal agent, whereas failure to achieve hemostasis was associated with more than a threefold higher relative risk for death (relative risk, 3.63; 95% confidence interval, 2.56-5.16).
“This has implications in practice because it emphasizes the need for achieving effective hemostasis, if not with only one agent, trying other agents or treatment modalities, because it is a strong predictor of survival,” lead author Antonio Gómez-Outes, MD, PhD, said in an interview.
The bad news, he said, is that the mortality rate was still significant, at 17.7%, and approximately half of patients with DOAC-related severe intracranial bleeding survived with long-term moderate/severe disability.
“The lesson is to prevent these bleeding events because once they appear, even if you give an antidote, the outcome is poor, particularly for intracranial bleeding,” said Dr. Gómez-Outes, division of pharmacology and clinical drug evaluation, Spanish Agency for Medicines and Medical Devices, Madrid.
To put this in context, mortality rates were close to 50% after intracranial bleeding a decade ago when there were no antidotes or reversal agents, he observed. “So to some extent, patient care has improved, and the outcome has improved, but there is a long road to improve regarding disability.”
More than 100,000 DOAC-related major bleeding cases occur each year in the United States and European Union, Dr. Gómez-Outes said, and about half are severe enough to require hospitalization and potentially the use of a reversal agent. These include idarucizumab (Praxbind) for dabigatran reversal and prothombin complex concentrates (4CCC) or andexanet alpha (Andexxa) for reversal of direct factor Xa inhibitors like rivaroxaban, apixaban, and edoxaban.
As reported in the June 22 issue of the Journal of the American College of Cardiology, the meta-analysis comprised 4,735 patients (mean age, 77 years; 57% male) with severe DOAC-related bleeding who received 4PCC (n = 2,688), idarucizumab (n = 1,111), or andexanet (n = 936) in 60 studies between January 2010 and December 2020.
Atrial fibrillation (AFib) was the most common reason for use of a DOAC (82%), followed by venous thromboembolism (14%). Rivaroxaban was used in 36%, apixaban in 32%, dabigatran in 31%, and edoxaban in 1%.
The index bleeding event was intracranial hemorrhage (ICH) in 55%. Anticoagulation was restarted in 57% of patients an average of 11 days after admission.
Mortality rates were 20.2% in patients with ICH and 15.4% in those with extracranial bleeding. There were no differences in death rates by reversal agent used, type of study, risk for bias, or study sponsorship in meta-regression analysis.
Rebleeding occurred in 13.2% of patients; 82.0% of these events were described as an ICH, and 78.0% occurred after anticoagulation was restarted.
The overall rate of thromboembolism was 4.6%. The risk was particularly high with andexanet, at 10.7%, and relatively low with idarucizumab (3.8%) and 4PCC (4.3%), the authors note.
“Our meta-analysis suggests specific reversal with andexanet is not superior to unspecific reversal with 4PCC, and that’s good news because many centers, in many countries, have no access to specific antidotes that are more costly,” Dr. Gómez-Outes said. “4PCC is an effective and relatively safe drug, so it’s still a good option for these patients.”
Labeling for andexanet includes a warning for thromboembolic events, but in the absence of direct comparisons, the findings should be interpreted with caution, he added. Further insights are expected from an ongoing randomized trial of andexanet and standard of care in 900 patients who present with acute ICH less than 15 hours after taking an oral factor Xa inhibitor. The preliminary completion date is set for 2023.
“The meta-analysis raises awareness about the rates of mortality and thromboembolism after reversal agent administration, although understanding the implications of these data is challenging,” Christopher Granger, MD, and Sean P. Pokomey, MD, MBA, Duke University Medical Center, Durham, N.C., say in an accompanying editorial.
The fact that failure to achieve hemostasis was associated with death is expected and might be related to the way hemostasis was defined, rather than the actual failure of the hemostatic treatments, they suggest. “The prothrombotic effects of each agent, including andexanet, need to be better understood, as clinicians work toward including reversal agents into algorithms for bleeding management.”
Effective hemostasis was defined in the studies through various methods as: “Excellent/good” using the Sarode and ANNEXA-4 scales; “yes” in the International Society on Thrombosis and Hemostasis Scale; and with other scales and through clinical judgment.
Although the size of the meta-analysis dwarfs previous reviews, the editorialists and authors point out that 47 of the 60 studies were retrospective, only two had control groups, and 45 had a high risk for bias.
In general, there was also poor reporting of key clinical data, such as postbleeding anticoagulation management, and a limitation of the mortality analysis is that it was based in selected patients with effective hemostasis assessed within 48 hours, which may not capture early deaths, the authors note.
“The morbidity and mortality from ischemic strokes as a result of undertreatment of stroke prevention in patients with AFib continue to dwarf the bleeding related mortality among patients with AFib and on DOACs, and thus the number one priority is to treat nearly all patients with AFib with a DOAC,” Dr. Granger and Dr. Pokomey conclude. “The availability of reversal agents for DOACs should provide reassurance, with another tool in our armamentarium, to providers to prescribe OACs for stroke prevention.”
No funding/grant support was received to conduct the study. Coauthor Ramón Lecumberri has received personal fees from Boehringer Ingelheim and Bristol Myers Squibb outside the submitted work. All other authors report no relevant financial relationships. Dr. Granger has received research and consulting fees from Bristol Myers Squibb, Pfizer, Boehringer Ingelheim, Bayer, Janssen, Boston Scientific, Apple, AstraZeneca, Novartis, AbbVie, Biomed, CeleCor, GSK, Novartis, Medtronic, Merck, Novo Nordisk, Philips, Rho, and the U.S. Food and Drug Administration. Dr. Pokomey has received modest consulting support from Bristol Myers Squibb, Pfizer, Boston Scientific, Medtronic, Janssen, and Zoll; modest research support from Gilead, Boston Scientific, Bristol Myers Squibb, Pfizer, and Janssen; and significant research support from the FDA.
A version of this article first appeared on Medscape.com.
Are left atrial thrombi that defy preprocedure anticoagulation predictable?
Three or more weeks of oral anticoagulation (OAC) sometimes isn’t up to the job of clearing any potentially embolic left atrial (LA) thrombi before procedures like cardioversion or catheter ablation in patients with atrial fibrillation (AF). Such OAC-defiant LA thrombi aren’t common, nor are they rare enough to ignore, suggests a new meta-analysis that might also have identified features that predispose to them.
Such predictors of LA clots that persist despite OAC could potentially guide selective use of transesophageal echocardiography (TEE) instead of more routine policies to either use or not use TEE for thrombus rule-out before rhythm-control procedures, researchers propose.
Their prevalence was about 2.7% among the study’s more than 14,000 patients who received at least 3 weeks of OAC with either vitamin K antagonists (VKA) or direct oral anticoagulants (DOAC) before undergoing TEE.
But OAC-resistant LA thrombi were two- to four-times as common in patients with than without certain features, including AF other than paroxysmal and higher CHADS2 and CHA2DS2-VASc stroke risk-stratification scores.
“TEE imaging in select patients at an elevated risk of LA thrombus, despite anticoagulation status, may be a reasonable approach to minimize the risk of thromboembolic complications following cardioversion or catheter ablation,” propose the study’s authors, led by Antony Lurie, BMSC, Population Health Research Institute, Hamilton, Ont. Their report was published in the June 15 issue of the Journal of the American College of Cardiology.
Guidelines don’t encourage TEE before cardioversion in patients who have been on OAC for at least 3 weeks, the group notes, and policies on TEE use before AF ablation vary widely regardless of anticoagulation status.
The current study suggests that 3 weeks of OAC isn’t enough for a substantial number of patients, who might be put at thromboembolic risk if TEE were to be skipped before rhythm-control procedures.
Conversely, many patients unlikely to have LA thrombi get preprocedure TEE anyway. That can happen “irrespective of how long they’ve been anticoagulated, their pattern of atrial fibrillation, or their stroke risk,” senior author Jorge A. Wong, MD, MPH, Population Health Research Institute and McMaster University, Hamilton, Ont., told this news organization.
But “TEE is an invasive imaging modality, so it is associated with small element of risk.” The current study, Dr. Wong said, points to potential risk-stratification tools clinicians might use to guide more selective TEE screening.
“At sites where TEEs are done all the time for patients undergoing ablation, one could use several of these risk markers to perhaps tailor use of TEE in individuals,” Dr. Wong said. “For example, in people with paroxysmal atrial fibrillation, we found that the risk of left atrial appendage clot was approximately 1% or less.” Screening by TEE might reasonably be avoided in such patients.
“Fortunately, continued oral anticoagulation already yields low peri-procedural stroke rates,” observes an accompanying editorial from Paulus Kirchhof, MD, and Christoph Sinning, MD, from the University Heart & Vascular Center and German Centre of Cardiovascular Research, Hamburg.
“Based on this new analysis of existing data, a risk-based use of TEE imaging in anticoagulated patients could enable further improvement in the safe delivery of rhythm control interventions in patients with AF,” the editorialists agree.
The meta-analysis covered 10 prospective and 25 retrospective studies with a total of 14,653 patients that reported whether LA thrombus was present in patients with AF or atrial flutter (AFL) who underwent TEE after at least 3 weeks of VKA or DOAC therapy. Reports for 30 of the studies identified patients by rhythm-control procedure, and the remaining five didn’t specify TEE indications.
The weighted mean prevalence of LA thrombus at TEE was 2.73% (95% confidence interval, 1.95%-3.80%). The finding was not significantly changed in separate sensitivity analyses, the report says, including one limited to studies with low risk of bias and others excluding patients with valvular AF, interrupted OAC, heparin bridging, or subtherapeutic anticoagulation, respectively.
Patients treated with VKA and DOACs showed similar prevalences of LA thrombi, with means of 2.80% and 3.12%, respectively (P = .674). The prevalence was significantly higher in patients:
- with nonparoxysmal than with paroxysmal AF/AFL (4.81% vs. 1.03%; P < .001)
- undergoing cardioversion than ablation (5.55% vs. 1.65; P < .001)
- with CHA2DS2-VASc scores of at least 3 than with scores of 2 or less (6.31% vs. 1.06%; P < .001).
A limitation of the study, observe Dr. Kirchhof and Dr. Sinning, “is that all patients had a clinical indication for a TEE, which might be a selection bias. When a thrombus was found on TEE, clinical judgment led to postponing of the procedure,” thereby avoiding potential thromboembolism.
“Thus, the paper cannot demonstrate that presence of a thrombus on TEE is related to peri-procedural ischemic stroke,” they write.
The literature puts the risk for stroke or systemic embolism at well under 1% for patients anticoagulated with either VKA or DOACs for at least 3 weeks prior to cardioversion, in contrast to the nearly 3% prevalence of LA appendage thrombus by TEE in the current analysis, Dr. Wong observed.
“So we’re seeing a lot more left atrial appendage thrombus than we would see stroke,” but there wasn’t a way to determine whether that increases the stroke risk, he agreed.Dr. Wong, Dr. Lurie, and the other authors report no relevant conflicts. Dr. Kirchhof discloses receiving partial support “from several drug and device companies active in atrial fibrillation” and to being listed as inventor on two AF-related patents held by the University of Birmingham. Dr. Sinning reports no relevant relationships.
A version of this article first appeared on Medscape.com.
Three or more weeks of oral anticoagulation (OAC) sometimes isn’t up to the job of clearing any potentially embolic left atrial (LA) thrombi before procedures like cardioversion or catheter ablation in patients with atrial fibrillation (AF). Such OAC-defiant LA thrombi aren’t common, nor are they rare enough to ignore, suggests a new meta-analysis that might also have identified features that predispose to them.
Such predictors of LA clots that persist despite OAC could potentially guide selective use of transesophageal echocardiography (TEE) instead of more routine policies to either use or not use TEE for thrombus rule-out before rhythm-control procedures, researchers propose.
Their prevalence was about 2.7% among the study’s more than 14,000 patients who received at least 3 weeks of OAC with either vitamin K antagonists (VKA) or direct oral anticoagulants (DOAC) before undergoing TEE.
But OAC-resistant LA thrombi were two- to four-times as common in patients with than without certain features, including AF other than paroxysmal and higher CHADS2 and CHA2DS2-VASc stroke risk-stratification scores.
“TEE imaging in select patients at an elevated risk of LA thrombus, despite anticoagulation status, may be a reasonable approach to minimize the risk of thromboembolic complications following cardioversion or catheter ablation,” propose the study’s authors, led by Antony Lurie, BMSC, Population Health Research Institute, Hamilton, Ont. Their report was published in the June 15 issue of the Journal of the American College of Cardiology.
Guidelines don’t encourage TEE before cardioversion in patients who have been on OAC for at least 3 weeks, the group notes, and policies on TEE use before AF ablation vary widely regardless of anticoagulation status.
The current study suggests that 3 weeks of OAC isn’t enough for a substantial number of patients, who might be put at thromboembolic risk if TEE were to be skipped before rhythm-control procedures.
Conversely, many patients unlikely to have LA thrombi get preprocedure TEE anyway. That can happen “irrespective of how long they’ve been anticoagulated, their pattern of atrial fibrillation, or their stroke risk,” senior author Jorge A. Wong, MD, MPH, Population Health Research Institute and McMaster University, Hamilton, Ont., told this news organization.
But “TEE is an invasive imaging modality, so it is associated with small element of risk.” The current study, Dr. Wong said, points to potential risk-stratification tools clinicians might use to guide more selective TEE screening.
“At sites where TEEs are done all the time for patients undergoing ablation, one could use several of these risk markers to perhaps tailor use of TEE in individuals,” Dr. Wong said. “For example, in people with paroxysmal atrial fibrillation, we found that the risk of left atrial appendage clot was approximately 1% or less.” Screening by TEE might reasonably be avoided in such patients.
“Fortunately, continued oral anticoagulation already yields low peri-procedural stroke rates,” observes an accompanying editorial from Paulus Kirchhof, MD, and Christoph Sinning, MD, from the University Heart & Vascular Center and German Centre of Cardiovascular Research, Hamburg.
“Based on this new analysis of existing data, a risk-based use of TEE imaging in anticoagulated patients could enable further improvement in the safe delivery of rhythm control interventions in patients with AF,” the editorialists agree.
The meta-analysis covered 10 prospective and 25 retrospective studies with a total of 14,653 patients that reported whether LA thrombus was present in patients with AF or atrial flutter (AFL) who underwent TEE after at least 3 weeks of VKA or DOAC therapy. Reports for 30 of the studies identified patients by rhythm-control procedure, and the remaining five didn’t specify TEE indications.
The weighted mean prevalence of LA thrombus at TEE was 2.73% (95% confidence interval, 1.95%-3.80%). The finding was not significantly changed in separate sensitivity analyses, the report says, including one limited to studies with low risk of bias and others excluding patients with valvular AF, interrupted OAC, heparin bridging, or subtherapeutic anticoagulation, respectively.
Patients treated with VKA and DOACs showed similar prevalences of LA thrombi, with means of 2.80% and 3.12%, respectively (P = .674). The prevalence was significantly higher in patients:
- with nonparoxysmal than with paroxysmal AF/AFL (4.81% vs. 1.03%; P < .001)
- undergoing cardioversion than ablation (5.55% vs. 1.65; P < .001)
- with CHA2DS2-VASc scores of at least 3 than with scores of 2 or less (6.31% vs. 1.06%; P < .001).
A limitation of the study, observe Dr. Kirchhof and Dr. Sinning, “is that all patients had a clinical indication for a TEE, which might be a selection bias. When a thrombus was found on TEE, clinical judgment led to postponing of the procedure,” thereby avoiding potential thromboembolism.
“Thus, the paper cannot demonstrate that presence of a thrombus on TEE is related to peri-procedural ischemic stroke,” they write.
The literature puts the risk for stroke or systemic embolism at well under 1% for patients anticoagulated with either VKA or DOACs for at least 3 weeks prior to cardioversion, in contrast to the nearly 3% prevalence of LA appendage thrombus by TEE in the current analysis, Dr. Wong observed.
“So we’re seeing a lot more left atrial appendage thrombus than we would see stroke,” but there wasn’t a way to determine whether that increases the stroke risk, he agreed.Dr. Wong, Dr. Lurie, and the other authors report no relevant conflicts. Dr. Kirchhof discloses receiving partial support “from several drug and device companies active in atrial fibrillation” and to being listed as inventor on two AF-related patents held by the University of Birmingham. Dr. Sinning reports no relevant relationships.
A version of this article first appeared on Medscape.com.
Three or more weeks of oral anticoagulation (OAC) sometimes isn’t up to the job of clearing any potentially embolic left atrial (LA) thrombi before procedures like cardioversion or catheter ablation in patients with atrial fibrillation (AF). Such OAC-defiant LA thrombi aren’t common, nor are they rare enough to ignore, suggests a new meta-analysis that might also have identified features that predispose to them.
Such predictors of LA clots that persist despite OAC could potentially guide selective use of transesophageal echocardiography (TEE) instead of more routine policies to either use or not use TEE for thrombus rule-out before rhythm-control procedures, researchers propose.
Their prevalence was about 2.7% among the study’s more than 14,000 patients who received at least 3 weeks of OAC with either vitamin K antagonists (VKA) or direct oral anticoagulants (DOAC) before undergoing TEE.
But OAC-resistant LA thrombi were two- to four-times as common in patients with than without certain features, including AF other than paroxysmal and higher CHADS2 and CHA2DS2-VASc stroke risk-stratification scores.
“TEE imaging in select patients at an elevated risk of LA thrombus, despite anticoagulation status, may be a reasonable approach to minimize the risk of thromboembolic complications following cardioversion or catheter ablation,” propose the study’s authors, led by Antony Lurie, BMSC, Population Health Research Institute, Hamilton, Ont. Their report was published in the June 15 issue of the Journal of the American College of Cardiology.
Guidelines don’t encourage TEE before cardioversion in patients who have been on OAC for at least 3 weeks, the group notes, and policies on TEE use before AF ablation vary widely regardless of anticoagulation status.
The current study suggests that 3 weeks of OAC isn’t enough for a substantial number of patients, who might be put at thromboembolic risk if TEE were to be skipped before rhythm-control procedures.
Conversely, many patients unlikely to have LA thrombi get preprocedure TEE anyway. That can happen “irrespective of how long they’ve been anticoagulated, their pattern of atrial fibrillation, or their stroke risk,” senior author Jorge A. Wong, MD, MPH, Population Health Research Institute and McMaster University, Hamilton, Ont., told this news organization.
But “TEE is an invasive imaging modality, so it is associated with small element of risk.” The current study, Dr. Wong said, points to potential risk-stratification tools clinicians might use to guide more selective TEE screening.
“At sites where TEEs are done all the time for patients undergoing ablation, one could use several of these risk markers to perhaps tailor use of TEE in individuals,” Dr. Wong said. “For example, in people with paroxysmal atrial fibrillation, we found that the risk of left atrial appendage clot was approximately 1% or less.” Screening by TEE might reasonably be avoided in such patients.
“Fortunately, continued oral anticoagulation already yields low peri-procedural stroke rates,” observes an accompanying editorial from Paulus Kirchhof, MD, and Christoph Sinning, MD, from the University Heart & Vascular Center and German Centre of Cardiovascular Research, Hamburg.
“Based on this new analysis of existing data, a risk-based use of TEE imaging in anticoagulated patients could enable further improvement in the safe delivery of rhythm control interventions in patients with AF,” the editorialists agree.
The meta-analysis covered 10 prospective and 25 retrospective studies with a total of 14,653 patients that reported whether LA thrombus was present in patients with AF or atrial flutter (AFL) who underwent TEE after at least 3 weeks of VKA or DOAC therapy. Reports for 30 of the studies identified patients by rhythm-control procedure, and the remaining five didn’t specify TEE indications.
The weighted mean prevalence of LA thrombus at TEE was 2.73% (95% confidence interval, 1.95%-3.80%). The finding was not significantly changed in separate sensitivity analyses, the report says, including one limited to studies with low risk of bias and others excluding patients with valvular AF, interrupted OAC, heparin bridging, or subtherapeutic anticoagulation, respectively.
Patients treated with VKA and DOACs showed similar prevalences of LA thrombi, with means of 2.80% and 3.12%, respectively (P = .674). The prevalence was significantly higher in patients:
- with nonparoxysmal than with paroxysmal AF/AFL (4.81% vs. 1.03%; P < .001)
- undergoing cardioversion than ablation (5.55% vs. 1.65; P < .001)
- with CHA2DS2-VASc scores of at least 3 than with scores of 2 or less (6.31% vs. 1.06%; P < .001).
A limitation of the study, observe Dr. Kirchhof and Dr. Sinning, “is that all patients had a clinical indication for a TEE, which might be a selection bias. When a thrombus was found on TEE, clinical judgment led to postponing of the procedure,” thereby avoiding potential thromboembolism.
“Thus, the paper cannot demonstrate that presence of a thrombus on TEE is related to peri-procedural ischemic stroke,” they write.
The literature puts the risk for stroke or systemic embolism at well under 1% for patients anticoagulated with either VKA or DOACs for at least 3 weeks prior to cardioversion, in contrast to the nearly 3% prevalence of LA appendage thrombus by TEE in the current analysis, Dr. Wong observed.
“So we’re seeing a lot more left atrial appendage thrombus than we would see stroke,” but there wasn’t a way to determine whether that increases the stroke risk, he agreed.Dr. Wong, Dr. Lurie, and the other authors report no relevant conflicts. Dr. Kirchhof discloses receiving partial support “from several drug and device companies active in atrial fibrillation” and to being listed as inventor on two AF-related patents held by the University of Birmingham. Dr. Sinning reports no relevant relationships.
A version of this article first appeared on Medscape.com.
AHA: Physical activity best first-line for high BP, cholesterol
The optimal first step to address mild to moderately elevated blood pressure and cholesterol in otherwise healthy adults is a “prescription” to sit less and move more, the American Heart Association says in a new scientific statement.
“The current American Heart Association guidelines for diagnosing high blood pressure and cholesterol recognize that otherwise healthy individuals with mildly or moderately elevated levels of these cardiovascular risk factors should actively attempt to reduce these risks,” Bethany Barone Gibbs, PhD, chair of the statement writing group, said in an AHA news release.
“The first treatment strategy for many of these patients should be healthy lifestyle changes beginning with increasing physical activity,” said Dr. Gibbs, from the University of Pittsburgh.
The 12-page AHA scientific statement – Physical Activity as a Critical Component of First-Line Treatment for Elevated Blood Pressure or Cholesterol: Who, What, and How? – was published online June 2 in Hypertension.
Every little bit helps
According to the AHA, about 21% of American adults have systolic blood pressure between 120 and 139 mm Hg, or diastolic blood pressure between 80 and 89 mm Hg, which meets the criteria for lifestyle-only treatment for elevated BP outlined in the American College of Cardiology (ACC)/AHA high blood pressure guideline.
In addition, about 28% of American adults have LDL cholesterol above 70 mg/dL and otherwise meet the low-risk criteria for heart disease or stroke. These individuals would meet the criteria for lifestyle-only treatment outlined in the 2018 ACC/AHA cholesterol treatment guidelines, which include increased physical activity, weight loss, better diet, smoking cessation, and moderating alcohol intake.
“Of the recommended lifestyle changes, increasing physical activity has extensive benefits, including improving both blood pressure and blood cholesterol, that are comparable, superior, or complementary to other healthy lifestyle changes,” the writing group says.
“Physical activity assessment and prescription are an excellent lifestyle behavior treatment option for all patients, including for the large population of mild-moderate-risk patients with elevated blood pressure and blood cholesterol,” they note.
Research has shown that increasing physical activity can lead to clinically meaningful 3 or 4 mm Hg reductions in systolic and diastolic blood pressure, and 3 to 6 mg/dL decreases in LDL cholesterol, the authors point out.
Previous evidence also shows that physically active people have a 21% lower risk of developing cardiovascular disease and a 36% lower risk for death from cardiovascular diseases than those who are not physically active.
Physical activity also has benefits beyond heart health, including a lower risk for some cancers; improved bone, brain, and mental health; and better sleep, they note.
The U.S. Department of Health and Human Services 2018 physical activity guidelines advise Americans to log 150 minutes of moderate-intensity aerobic exercise or 75 minutes of vigorous aerobic activity each week and to participate in two or more weekly strength training sessions.
However, there is no minimum amount of time to receive benefits from physical activity.
“Every little bit of activity is better than none. Even small initial increases of 5 to 10 minutes a day can yield health benefits,” Dr. Gibbs said.
Translational advice for clinicians
The AHA statement encourages clinicians to ask patients about their physical activity at every interaction; provide ideas and resources to help patients improve and sustain regular life-long physical activity; and encourage and celebrate small increases in activity, such as walking more or taking the stairs, to help with motivation.
“In our world where physical activity is increasingly engineered out of our lives and the overwhelming default is to sit – and even more so now as the nation and the world is practicing quarantine and isolation to reduce the spread of coronavirus – the message that we must be relentless in our pursuit to ‘sit less and move more’ throughout the day is more important than ever,” said Dr. Gibbs.
The statement was prepared by a volunteer writing group on behalf of the AHA Council on Lifestyle and Cardiometabolic Health; the Council on Cardiovascular and Stroke Nursing; and the Council on Clinical Cardiology.
This research had no commercial funding. A list of disclosures for the writing group is available with the original article.
A version of this article first appeared on Medscape.com.
The optimal first step to address mild to moderately elevated blood pressure and cholesterol in otherwise healthy adults is a “prescription” to sit less and move more, the American Heart Association says in a new scientific statement.
“The current American Heart Association guidelines for diagnosing high blood pressure and cholesterol recognize that otherwise healthy individuals with mildly or moderately elevated levels of these cardiovascular risk factors should actively attempt to reduce these risks,” Bethany Barone Gibbs, PhD, chair of the statement writing group, said in an AHA news release.
“The first treatment strategy for many of these patients should be healthy lifestyle changes beginning with increasing physical activity,” said Dr. Gibbs, from the University of Pittsburgh.
The 12-page AHA scientific statement – Physical Activity as a Critical Component of First-Line Treatment for Elevated Blood Pressure or Cholesterol: Who, What, and How? – was published online June 2 in Hypertension.
Every little bit helps
According to the AHA, about 21% of American adults have systolic blood pressure between 120 and 139 mm Hg, or diastolic blood pressure between 80 and 89 mm Hg, which meets the criteria for lifestyle-only treatment for elevated BP outlined in the American College of Cardiology (ACC)/AHA high blood pressure guideline.
In addition, about 28% of American adults have LDL cholesterol above 70 mg/dL and otherwise meet the low-risk criteria for heart disease or stroke. These individuals would meet the criteria for lifestyle-only treatment outlined in the 2018 ACC/AHA cholesterol treatment guidelines, which include increased physical activity, weight loss, better diet, smoking cessation, and moderating alcohol intake.
“Of the recommended lifestyle changes, increasing physical activity has extensive benefits, including improving both blood pressure and blood cholesterol, that are comparable, superior, or complementary to other healthy lifestyle changes,” the writing group says.
“Physical activity assessment and prescription are an excellent lifestyle behavior treatment option for all patients, including for the large population of mild-moderate-risk patients with elevated blood pressure and blood cholesterol,” they note.
Research has shown that increasing physical activity can lead to clinically meaningful 3 or 4 mm Hg reductions in systolic and diastolic blood pressure, and 3 to 6 mg/dL decreases in LDL cholesterol, the authors point out.
Previous evidence also shows that physically active people have a 21% lower risk of developing cardiovascular disease and a 36% lower risk for death from cardiovascular diseases than those who are not physically active.
Physical activity also has benefits beyond heart health, including a lower risk for some cancers; improved bone, brain, and mental health; and better sleep, they note.
The U.S. Department of Health and Human Services 2018 physical activity guidelines advise Americans to log 150 minutes of moderate-intensity aerobic exercise or 75 minutes of vigorous aerobic activity each week and to participate in two or more weekly strength training sessions.
However, there is no minimum amount of time to receive benefits from physical activity.
“Every little bit of activity is better than none. Even small initial increases of 5 to 10 minutes a day can yield health benefits,” Dr. Gibbs said.
Translational advice for clinicians
The AHA statement encourages clinicians to ask patients about their physical activity at every interaction; provide ideas and resources to help patients improve and sustain regular life-long physical activity; and encourage and celebrate small increases in activity, such as walking more or taking the stairs, to help with motivation.
“In our world where physical activity is increasingly engineered out of our lives and the overwhelming default is to sit – and even more so now as the nation and the world is practicing quarantine and isolation to reduce the spread of coronavirus – the message that we must be relentless in our pursuit to ‘sit less and move more’ throughout the day is more important than ever,” said Dr. Gibbs.
The statement was prepared by a volunteer writing group on behalf of the AHA Council on Lifestyle and Cardiometabolic Health; the Council on Cardiovascular and Stroke Nursing; and the Council on Clinical Cardiology.
This research had no commercial funding. A list of disclosures for the writing group is available with the original article.
A version of this article first appeared on Medscape.com.
The optimal first step to address mild to moderately elevated blood pressure and cholesterol in otherwise healthy adults is a “prescription” to sit less and move more, the American Heart Association says in a new scientific statement.
“The current American Heart Association guidelines for diagnosing high blood pressure and cholesterol recognize that otherwise healthy individuals with mildly or moderately elevated levels of these cardiovascular risk factors should actively attempt to reduce these risks,” Bethany Barone Gibbs, PhD, chair of the statement writing group, said in an AHA news release.
“The first treatment strategy for many of these patients should be healthy lifestyle changes beginning with increasing physical activity,” said Dr. Gibbs, from the University of Pittsburgh.
The 12-page AHA scientific statement – Physical Activity as a Critical Component of First-Line Treatment for Elevated Blood Pressure or Cholesterol: Who, What, and How? – was published online June 2 in Hypertension.
Every little bit helps
According to the AHA, about 21% of American adults have systolic blood pressure between 120 and 139 mm Hg, or diastolic blood pressure between 80 and 89 mm Hg, which meets the criteria for lifestyle-only treatment for elevated BP outlined in the American College of Cardiology (ACC)/AHA high blood pressure guideline.
In addition, about 28% of American adults have LDL cholesterol above 70 mg/dL and otherwise meet the low-risk criteria for heart disease or stroke. These individuals would meet the criteria for lifestyle-only treatment outlined in the 2018 ACC/AHA cholesterol treatment guidelines, which include increased physical activity, weight loss, better diet, smoking cessation, and moderating alcohol intake.
“Of the recommended lifestyle changes, increasing physical activity has extensive benefits, including improving both blood pressure and blood cholesterol, that are comparable, superior, or complementary to other healthy lifestyle changes,” the writing group says.
“Physical activity assessment and prescription are an excellent lifestyle behavior treatment option for all patients, including for the large population of mild-moderate-risk patients with elevated blood pressure and blood cholesterol,” they note.
Research has shown that increasing physical activity can lead to clinically meaningful 3 or 4 mm Hg reductions in systolic and diastolic blood pressure, and 3 to 6 mg/dL decreases in LDL cholesterol, the authors point out.
Previous evidence also shows that physically active people have a 21% lower risk of developing cardiovascular disease and a 36% lower risk for death from cardiovascular diseases than those who are not physically active.
Physical activity also has benefits beyond heart health, including a lower risk for some cancers; improved bone, brain, and mental health; and better sleep, they note.
The U.S. Department of Health and Human Services 2018 physical activity guidelines advise Americans to log 150 minutes of moderate-intensity aerobic exercise or 75 minutes of vigorous aerobic activity each week and to participate in two or more weekly strength training sessions.
However, there is no minimum amount of time to receive benefits from physical activity.
“Every little bit of activity is better than none. Even small initial increases of 5 to 10 minutes a day can yield health benefits,” Dr. Gibbs said.
Translational advice for clinicians
The AHA statement encourages clinicians to ask patients about their physical activity at every interaction; provide ideas and resources to help patients improve and sustain regular life-long physical activity; and encourage and celebrate small increases in activity, such as walking more or taking the stairs, to help with motivation.
“In our world where physical activity is increasingly engineered out of our lives and the overwhelming default is to sit – and even more so now as the nation and the world is practicing quarantine and isolation to reduce the spread of coronavirus – the message that we must be relentless in our pursuit to ‘sit less and move more’ throughout the day is more important than ever,” said Dr. Gibbs.
The statement was prepared by a volunteer writing group on behalf of the AHA Council on Lifestyle and Cardiometabolic Health; the Council on Cardiovascular and Stroke Nursing; and the Council on Clinical Cardiology.
This research had no commercial funding. A list of disclosures for the writing group is available with the original article.
A version of this article first appeared on Medscape.com.
Evidence builds for iPhone 12 interference with cardiac devices
Further evidence that powerful magnets in some Apple iPhones can interfere with cardiac implantable electronic devices (CIEDs) comes from a small study that also suggests some devices are more susceptible than others.
The iPhone 12 Pro Max with MagSafe technology interfered with CIEDs implanted in three consecutive patients presenting to an electrophysiology lab and in 8 of 11 implantable cardioverter defibrillators (ICDs) and pacemakers (72.7%) still in their original packaging.
The results, published in the Journal of the American Heart Association, are consistent with a widely publicized single-patient report this February and evidence of electromagnetic interference with fitness wristbands and e-cigarettes.
The MagSafe technology supports wireless charging and is optimized by a ring-shaped array of magnets. Although magnet mode activation has been shown to occur in CIEDs with exposure to a magnetic field as low as 10 gauss, the field strength of the iPhone 12 Pro Max can be greater than 50 G when in direct contact, the researchers determined.
“If this becomes a standard in a lot of the new smartphones or companies start to use stronger magnets ... then we will see more and more of these consumer electronic and device interactions,” senior author Michael Wu, MD, Brown University, Providence, R.I., told this news organization.
In a May advisory on these device interactions, the U.S. Food and Drug Administration also cautioned that the number of consumer electronics with strong magnets is expected to increase over time.
That trend appears to be already underway, with Forbes reporting in February that the MagSafe batteries will be “getting stronger” as part of upgrades to the iPhone 13 and Bloomberg reporting in advance of Apple’s annual developers conference this week that an upgraded version of MagSafe is in the works to support wireless charging for its iPad. MagSafe has not been used previously in iPads.
Although Apple has acknowledged that the iPhone 12 contains more magnets than previous iPhone models, it says “they’re not expected to pose a greater risk of magnetic interference to medical devices than prior iPhone models.” The company maintains a page that specifically warns about the potential for interactions and advises that consumers keep the iPhone and MagSafe accessories more than 15 cm (6 inches) away from medical devices.
Older-generation iPhones have not shown this risk, with only one case of interference reported with the iPhone 6 and an Apple Watch in 1,352 tests among 148 patients with CIEDs and leads from four different manufacturers.
In the present study, magnet reversion mode was triggered in all three patients when the iPhone 12 Pro Max was placed on the skin over the device.
The phone inhibited tachycardia therapies in Medtronic’s Amplia MRI Quad CRT-D and Abbott’s 1231-40 Fortify VR device.
The Boston Scientific V273 Intua CRT-P device, however, “appeared to be less susceptible, as we were only able to elicit transient temporary asynchronous pacing but no sustained response by the iPhone 12 Pro Max magnet,” Dr. Wu and colleagues note.
Among the 11 ex vivo CIEDs tested, placing the iPhone 12 Pro Max directly over the packaged device inhibited tachytherapies in Medtronic’s Visia AF MRI ICD and Abbott’s Fortify Assura DR ICD and Ellipse DR ICD.
The phone also led to asynchronous pacing in Medtronic’s Azure, Advisa MRI, and Adapta pacemakers and in Abbott’s Assurity MRI pacemaker.
Boston Scientific devices again “appeared to be less susceptible, as no clear magnet interference” was noted in the Dynagen ICD, Emblem MRI S-ICD, or Accolade MRI pacemaker, Dr. Wu reported. There was temporary asynchronous pacing but no sustained response in the company’s U125 Valitude pacemaker.
Using the Medtronic Visia AF MRI ICD, the researchers found that the iPhone 12 Pro Max was able to trigger magnet reversion mode at a distance up to 1.5 cm (0.6 inch) from the anterior aspect of the device ex vivo.
The difference in magnet response to the iPhone 12 Pro Max among the different devices is likely due to different hall-sensor magnet sensitivity, as all of the devices were susceptible to a standard donut magnet, Dr. Wu noted. Boston Scientific’s Accolade MRI pacemaker, for example, requires a magnet stronger than 70 G to activate magnet mode, according to the product manual.
“Even so, sometimes with our test, we were able to trigger a brief response,” he said. “The response isn’t as lasting as some of the other companies, but with the small sample size, I can only speculate and suggest that maybe it’s possible. But we always want a formal study through the company or other agencies to really pinpoint which company has more susceptible devices.”
As to whether manufacturers should build CIEDs less susceptible to today’s stronger magnets, Dr. Wu said it’s worth exploring, but there are pros and cons.
Although magnets in consumer devices have the potential to inhibit lifesaving therapies, a magnet is also very useful in certain medical settings, such as a quick way to ensure pacing without worrying about electrocautery noise during surgery or to deactivate a defibrillator if there’s noise resulting in inappropriate shocks.
“It would require an overhaul of a lot of the devices going forward, and I think that’s something that’s worth exploring, especially now that a lot of devices are using wireless communication, Bluetooth, and other communication technology,” he said.
Even though the study is small, Dr. Wu said, it does represent many of the available devices and has clinical implications, given that people often put their smartphones in a breast pocket.
“This report highlights the importance of public awareness regarding an interaction between CIEDs and a recently released smartphone model with magnetic charging capability,” Dr. Wu and colleagues conclude.
Apple was contacted for comment but had not responded at press time.
The authors reported no study funding or relevant conflicts of interests.
A version of this article first appeared on Medscape.com.
Further evidence that powerful magnets in some Apple iPhones can interfere with cardiac implantable electronic devices (CIEDs) comes from a small study that also suggests some devices are more susceptible than others.
The iPhone 12 Pro Max with MagSafe technology interfered with CIEDs implanted in three consecutive patients presenting to an electrophysiology lab and in 8 of 11 implantable cardioverter defibrillators (ICDs) and pacemakers (72.7%) still in their original packaging.
The results, published in the Journal of the American Heart Association, are consistent with a widely publicized single-patient report this February and evidence of electromagnetic interference with fitness wristbands and e-cigarettes.
The MagSafe technology supports wireless charging and is optimized by a ring-shaped array of magnets. Although magnet mode activation has been shown to occur in CIEDs with exposure to a magnetic field as low as 10 gauss, the field strength of the iPhone 12 Pro Max can be greater than 50 G when in direct contact, the researchers determined.
“If this becomes a standard in a lot of the new smartphones or companies start to use stronger magnets ... then we will see more and more of these consumer electronic and device interactions,” senior author Michael Wu, MD, Brown University, Providence, R.I., told this news organization.
In a May advisory on these device interactions, the U.S. Food and Drug Administration also cautioned that the number of consumer electronics with strong magnets is expected to increase over time.
That trend appears to be already underway, with Forbes reporting in February that the MagSafe batteries will be “getting stronger” as part of upgrades to the iPhone 13 and Bloomberg reporting in advance of Apple’s annual developers conference this week that an upgraded version of MagSafe is in the works to support wireless charging for its iPad. MagSafe has not been used previously in iPads.
Although Apple has acknowledged that the iPhone 12 contains more magnets than previous iPhone models, it says “they’re not expected to pose a greater risk of magnetic interference to medical devices than prior iPhone models.” The company maintains a page that specifically warns about the potential for interactions and advises that consumers keep the iPhone and MagSafe accessories more than 15 cm (6 inches) away from medical devices.
Older-generation iPhones have not shown this risk, with only one case of interference reported with the iPhone 6 and an Apple Watch in 1,352 tests among 148 patients with CIEDs and leads from four different manufacturers.
In the present study, magnet reversion mode was triggered in all three patients when the iPhone 12 Pro Max was placed on the skin over the device.
The phone inhibited tachycardia therapies in Medtronic’s Amplia MRI Quad CRT-D and Abbott’s 1231-40 Fortify VR device.
The Boston Scientific V273 Intua CRT-P device, however, “appeared to be less susceptible, as we were only able to elicit transient temporary asynchronous pacing but no sustained response by the iPhone 12 Pro Max magnet,” Dr. Wu and colleagues note.
Among the 11 ex vivo CIEDs tested, placing the iPhone 12 Pro Max directly over the packaged device inhibited tachytherapies in Medtronic’s Visia AF MRI ICD and Abbott’s Fortify Assura DR ICD and Ellipse DR ICD.
The phone also led to asynchronous pacing in Medtronic’s Azure, Advisa MRI, and Adapta pacemakers and in Abbott’s Assurity MRI pacemaker.
Boston Scientific devices again “appeared to be less susceptible, as no clear magnet interference” was noted in the Dynagen ICD, Emblem MRI S-ICD, or Accolade MRI pacemaker, Dr. Wu reported. There was temporary asynchronous pacing but no sustained response in the company’s U125 Valitude pacemaker.
Using the Medtronic Visia AF MRI ICD, the researchers found that the iPhone 12 Pro Max was able to trigger magnet reversion mode at a distance up to 1.5 cm (0.6 inch) from the anterior aspect of the device ex vivo.
The difference in magnet response to the iPhone 12 Pro Max among the different devices is likely due to different hall-sensor magnet sensitivity, as all of the devices were susceptible to a standard donut magnet, Dr. Wu noted. Boston Scientific’s Accolade MRI pacemaker, for example, requires a magnet stronger than 70 G to activate magnet mode, according to the product manual.
“Even so, sometimes with our test, we were able to trigger a brief response,” he said. “The response isn’t as lasting as some of the other companies, but with the small sample size, I can only speculate and suggest that maybe it’s possible. But we always want a formal study through the company or other agencies to really pinpoint which company has more susceptible devices.”
As to whether manufacturers should build CIEDs less susceptible to today’s stronger magnets, Dr. Wu said it’s worth exploring, but there are pros and cons.
Although magnets in consumer devices have the potential to inhibit lifesaving therapies, a magnet is also very useful in certain medical settings, such as a quick way to ensure pacing without worrying about electrocautery noise during surgery or to deactivate a defibrillator if there’s noise resulting in inappropriate shocks.
“It would require an overhaul of a lot of the devices going forward, and I think that’s something that’s worth exploring, especially now that a lot of devices are using wireless communication, Bluetooth, and other communication technology,” he said.
Even though the study is small, Dr. Wu said, it does represent many of the available devices and has clinical implications, given that people often put their smartphones in a breast pocket.
“This report highlights the importance of public awareness regarding an interaction between CIEDs and a recently released smartphone model with magnetic charging capability,” Dr. Wu and colleagues conclude.
Apple was contacted for comment but had not responded at press time.
The authors reported no study funding or relevant conflicts of interests.
A version of this article first appeared on Medscape.com.
Further evidence that powerful magnets in some Apple iPhones can interfere with cardiac implantable electronic devices (CIEDs) comes from a small study that also suggests some devices are more susceptible than others.
The iPhone 12 Pro Max with MagSafe technology interfered with CIEDs implanted in three consecutive patients presenting to an electrophysiology lab and in 8 of 11 implantable cardioverter defibrillators (ICDs) and pacemakers (72.7%) still in their original packaging.
The results, published in the Journal of the American Heart Association, are consistent with a widely publicized single-patient report this February and evidence of electromagnetic interference with fitness wristbands and e-cigarettes.
The MagSafe technology supports wireless charging and is optimized by a ring-shaped array of magnets. Although magnet mode activation has been shown to occur in CIEDs with exposure to a magnetic field as low as 10 gauss, the field strength of the iPhone 12 Pro Max can be greater than 50 G when in direct contact, the researchers determined.
“If this becomes a standard in a lot of the new smartphones or companies start to use stronger magnets ... then we will see more and more of these consumer electronic and device interactions,” senior author Michael Wu, MD, Brown University, Providence, R.I., told this news organization.
In a May advisory on these device interactions, the U.S. Food and Drug Administration also cautioned that the number of consumer electronics with strong magnets is expected to increase over time.
That trend appears to be already underway, with Forbes reporting in February that the MagSafe batteries will be “getting stronger” as part of upgrades to the iPhone 13 and Bloomberg reporting in advance of Apple’s annual developers conference this week that an upgraded version of MagSafe is in the works to support wireless charging for its iPad. MagSafe has not been used previously in iPads.
Although Apple has acknowledged that the iPhone 12 contains more magnets than previous iPhone models, it says “they’re not expected to pose a greater risk of magnetic interference to medical devices than prior iPhone models.” The company maintains a page that specifically warns about the potential for interactions and advises that consumers keep the iPhone and MagSafe accessories more than 15 cm (6 inches) away from medical devices.
Older-generation iPhones have not shown this risk, with only one case of interference reported with the iPhone 6 and an Apple Watch in 1,352 tests among 148 patients with CIEDs and leads from four different manufacturers.
In the present study, magnet reversion mode was triggered in all three patients when the iPhone 12 Pro Max was placed on the skin over the device.
The phone inhibited tachycardia therapies in Medtronic’s Amplia MRI Quad CRT-D and Abbott’s 1231-40 Fortify VR device.
The Boston Scientific V273 Intua CRT-P device, however, “appeared to be less susceptible, as we were only able to elicit transient temporary asynchronous pacing but no sustained response by the iPhone 12 Pro Max magnet,” Dr. Wu and colleagues note.
Among the 11 ex vivo CIEDs tested, placing the iPhone 12 Pro Max directly over the packaged device inhibited tachytherapies in Medtronic’s Visia AF MRI ICD and Abbott’s Fortify Assura DR ICD and Ellipse DR ICD.
The phone also led to asynchronous pacing in Medtronic’s Azure, Advisa MRI, and Adapta pacemakers and in Abbott’s Assurity MRI pacemaker.
Boston Scientific devices again “appeared to be less susceptible, as no clear magnet interference” was noted in the Dynagen ICD, Emblem MRI S-ICD, or Accolade MRI pacemaker, Dr. Wu reported. There was temporary asynchronous pacing but no sustained response in the company’s U125 Valitude pacemaker.
Using the Medtronic Visia AF MRI ICD, the researchers found that the iPhone 12 Pro Max was able to trigger magnet reversion mode at a distance up to 1.5 cm (0.6 inch) from the anterior aspect of the device ex vivo.
The difference in magnet response to the iPhone 12 Pro Max among the different devices is likely due to different hall-sensor magnet sensitivity, as all of the devices were susceptible to a standard donut magnet, Dr. Wu noted. Boston Scientific’s Accolade MRI pacemaker, for example, requires a magnet stronger than 70 G to activate magnet mode, according to the product manual.
“Even so, sometimes with our test, we were able to trigger a brief response,” he said. “The response isn’t as lasting as some of the other companies, but with the small sample size, I can only speculate and suggest that maybe it’s possible. But we always want a formal study through the company or other agencies to really pinpoint which company has more susceptible devices.”
As to whether manufacturers should build CIEDs less susceptible to today’s stronger magnets, Dr. Wu said it’s worth exploring, but there are pros and cons.
Although magnets in consumer devices have the potential to inhibit lifesaving therapies, a magnet is also very useful in certain medical settings, such as a quick way to ensure pacing without worrying about electrocautery noise during surgery or to deactivate a defibrillator if there’s noise resulting in inappropriate shocks.
“It would require an overhaul of a lot of the devices going forward, and I think that’s something that’s worth exploring, especially now that a lot of devices are using wireless communication, Bluetooth, and other communication technology,” he said.
Even though the study is small, Dr. Wu said, it does represent many of the available devices and has clinical implications, given that people often put their smartphones in a breast pocket.
“This report highlights the importance of public awareness regarding an interaction between CIEDs and a recently released smartphone model with magnetic charging capability,” Dr. Wu and colleagues conclude.
Apple was contacted for comment but had not responded at press time.
The authors reported no study funding or relevant conflicts of interests.
A version of this article first appeared on Medscape.com.