You are leaving Medscape Education
Cancel Continue
Log in to save activities Your saved activities will show here so that you can easily access them whenever you're ready. Log in here CME & Education Log in to keep track of your credits.
 

CME / ABIM MOC / CE

Does a Paradox Exist Between Obesity and Newly Diagnosed Atrial Fibrillation?

  • Authors: News Author: Steve Stiles; CME Author: Charles P. Vega, MD
  • CME / ABIM MOC / CE Released: 10/14/2022
  • Valid for credit through: 10/14/2023
Start Activity

  • Credits Available

    Physicians - maximum of 0.25 AMA PRA Category 1 Credit(s)™

    ABIM Diplomates - maximum of 0.25 ABIM MOC points

    Nurses - 0.25 ANCC Contact Hour(s) (0 contact hours are in the area of pharmacology)

    Pharmacists - 0.25 Knowledge-based ACPE (0.025 CEUs)

    Physician Assistant - 0.25 AAPA hour(s) of Category I credit

    IPCE - 0.25 Interprofessional Continuing Education (IPCE) credit

    You Are Eligible For

    • Letter of Completion
    • ABIM MOC points

Target Audience and Goal Statement

This activity is intended for primary care physicians, cardiologists, endocrinologists, nurses, pharmacists, physician assistants, and other members of the healthcare team who treat and manage adults with atrial fibrillation.

The goal of this activity is for learners to be better able to distinguish body mass index values associated with a lower risk for stroke in the setting of atrial fibrillation.

Upon completion of this activity, participants will:

  • Assess the association between height and cardiovascular events among adults
  • Distinguish body mass index values associated with a lower risk for stroke in the setting of atrial fibrillation
  • Outline implications for the healthcare team


Disclosures

Medscape, LLC requires every individual in a position to control educational content to disclose all financial relationships with ineligible companies that have occurred within the past 24 months. Ineligible companies are organizations whose primary business is producing, marketing, selling, re-selling, or distributing healthcare products used by or on patients.

All relevant financial relationships for anyone with the ability to control the content of this educational activity are listed below and have been mitigated. Others involved in the planning of this activity have no relevant financial relationships.


News Author

  • Steve Stiles

    News Editor, theheart.org | Medscape Cardiology

    Disclosures

    Steve Stiles has no relevant financial relationships.

CME Author

  • Charles P. Vega, MD

    Health Sciences Clinical Professor of Family Medicine
    University of California, Irvine School of Medicine

    Disclosures

    Charles P. Vega, MD, has the following relevant financial relationships:
    Consultant or advisor for: GlaxoSmithKline; Johnson & Johnson Pharmaceutical Research & Development, L.L.C.

Editor/Nurse Planner

  • Leigh Schmidt, MSN, RN, CNE, CHCP

    Associate Director, Accreditation and Compliance, Medscape, LLC

    Disclosures

    Leigh Schmidt, MSN, RN, CNE, CHCP, has no relevant financial relationships.

Compliance Reviewer

  • Amanda Jett, PharmD, BCACP

    Associate Director, Accreditation and Compliance, Medscape, LLC

    Disclosures

    Amanda Jett, PharmD, BCACP, has no relevant financial relationships.


Accreditation Statements



In support of improving patient care, Medscape, LLC is jointly accredited with commendation by the Accreditation Council for Continuing Medical Education (ACCME), the Accreditation Council for Pharmacy Education (ACPE), and the American Nurses Credentialing Center (ANCC), to provide continuing education for the healthcare team.

This activity was planned by and for the healthcare team, and learners will receive 0.25 Interprofessional Continuing Education (IPCE) credit for learning and change.

    For Physicians

  • Medscape, LLC designates this enduring material for a maximum of 0.25 AMA PRA Category 1 Credit(s)™ . Physicians should claim only the credit commensurate with the extent of their participation in the activity.

    Successful completion of this CME activity, which includes participation in the evaluation component, enables the participant to earn up to 0.25 MOC points in the American Board of Internal Medicine's (ABIM) Maintenance of Certification (MOC) program. Participants will earn MOC points equivalent to the amount of CME credits claimed for the activity. It is the CME activity provider's responsibility to submit participant completion information to ACCME for the purpose of granting ABIM MOC credit.

    Contact This Provider

    For Nurses

  • Awarded 0.25 contact hour(s) of nursing continuing professional development for RNs and APNs; 0.00 contact hours are in the area of pharmacology.

    Contact This Provider

    For Pharmacists

  • Medscape designates this continuing education activity for 0.25 contact hour(s) (0.025 CEUs) (Universal Activity Number: JA0007105-0000-22-319-H01-P).

    Contact This Provider

  • For Physician Assistants

    Medscape, LLC has been authorized by the American Academy of PAs (AAPA) to award AAPA Category 1 CME credit for activities planned in accordance with AAPA CME Criteria. This activity is designated for 0.25 AAPA Category 1 CME credits. Approval is valid until 10/14/2023. PAs should only claim credit commensurate with the extent of their participation.

For questions regarding the content of this activity, contact the accredited provider for this CME/CE activity noted above. For technical assistance, contact [email protected]


Instructions for Participation and Credit

There are no fees for participating in or receiving credit for this online educational activity. For information on applicability and acceptance of continuing education credit for this activity, please consult your professional licensing board.

This activity is designed to be completed within the time designated on the title page; physicians should claim only those credits that reflect the time actually spent in the activity. To successfully earn credit, participants must complete the activity online during the valid credit period that is noted on the title page. To receive AMA PRA Category 1 Credit™, you must receive a minimum score of 75% on the post-test.

Follow these steps to earn CME/CE credit*:

  1. Read the target audience, learning objectives, and author disclosures.
  2. Study the educational content online or printed out.
  3. Online, choose the best answer to each test question. To receive a certificate, you must receive a passing score as designated at the top of the test. We encourage you to complete the Activity Evaluation to provide feedback for future programming.

You may now view or print the certificate from your CME/CE Tracker. You may print the certificate but you cannot alter it. Credits will be tallied in your CME/CE Tracker and archived for 6 years; at any point within this time period you can print out the tally as well as the certificates from the CME/CE Tracker.

*The credit that you receive is based on your user profile.

CME / ABIM MOC / CE

Does a Paradox Exist Between Obesity and Newly Diagnosed Atrial Fibrillation?

Authors: News Author: Steve Stiles; CME Author: Charles P. Vega, MDFaculty and Disclosures

CME / ABIM MOC / CE Released: 10/14/2022

Valid for credit through: 10/14/2023

processing....

Clinical Context

Healthcare professionals are used to focusing on the "mass" in body mass index (BMI), but perhaps should be looking at the denominator of the BMI. Multiple observational studies have demonstrated a higher risk for cardiovascular disease, including stroke, associated with short stature. However, the role of atrial fibrillation (AF) in the risk for stroke among shorter adults was not clear until Moon and colleagues evaluated this issue in the July 1, 2014, issue of the International Journal of Cardiology.[1]

The researchers evaluated 558 patients with AF, 211 of whom had a history of ischemic stroke. The average height was 5 cm lower in comparing the stroke vs nonstroke cohorts, and short stature was found to be an independent risk factor for ischemic stroke in AF. It was also associated with a higher risk for diastolic dysfunction.

The current study reevaluates BMI as a potential risk factor for stroke among adults with AF.

Study Synopsis and Perspective

The relationship between BMI and all-cause mortality in patients with AF is U-shaped, with the risk highest in those who are underweight or severely obese and lowest in patients defined simply as obese, a registry analysis suggests. It also showed a similar relationship between BMI and risk for new or worsening heart failure (HF).

Mortality bottomed out at a BMI of about 30 to 35 kg/m2, which suggests that mild obesity was protective compared even with "normal-weight" or "overweight" BMI. Still, mortality went up sharply from there with rising BMI.

But higher BMI, a surrogate for obesity, apparently did not worsen outcomes by itself. The risk for death from any cause at higher obesity levels was found to depend a lot on related risk factors and comorbidities when the analysis controlled for conditions such as diabetes and hypertension.

The findings suggest an inverse relationship between BMI and all-cause mortality in AF only for patients with BMI less than about 30 kg/m2. The researchers therefore argue against any "obesity paradox" in AF that posits consistently better survival with increasing levels of obesity, based on their analysis of patients with new-onset AF in the GARFIELD-AF registry.

"It's common practice now for clinicians to discuss weight within a clinic setting when they're talking to their AF patients," observed Christian Fielder Camm, BM, BCh, from the University of Oxford, and Royal Berkshire NHS Foundation Trust, Reading, United Kingdom. Therefore, studies suggesting an inverse association between BMI and AF-related risk can be a concern.

Such studies "seem to suggest that once you've got AF, maintaining a high or very high BMI may in some way be protective, which is contrary to what would seem to make sense and certainly contrary to what our results have shown," Camm told theheart.org | Medscape Cardiology.

"I think that having further evidence now to suggest, actually, that greater BMI is associated with a greater risk of all-cause mortality and heart failure helps reframe that discussion at the physician-patient interaction level more clearly, and ensures that we're able to talk to our patients appropriately about risks associated with BMI and atrial fibrillation," said Camm, who is lead author on the analysis published August 6 in Open Heart.[2]

"Obesity is a cause of most cardiovascular diseases, but [these] data would support that being overweight or having mild obesity does not increase the risk," observed Carl J. Lavie, MD, from the John Ochsner Heart and Vascular Institute and University of Queensland School of Medicine, New Orleans, Louisiana.

"At a BMI of 40, it's very important for them to lose weight for their long-term prognosis," Dr Lavie noted, but "at a BMI of 30, the important thing would be to prevent further weight gain. And if they could keep their BMI of 30, they should have a good prognosis. Their prognosis would be particularly good if they didn't gain weight and put themselves in a more extreme obesity class that is associated with worse risk."

The current analysis, Dr Lavie said, "is way better than the AFFIRM study," which yielded an obesity-paradox report on its patients with AF about a dozen years ago. "It's got more data, more numbers, more statistical power," and breaks BMI into more categories.

That previous analysis, based on the influential AFFIRM randomized trial, separated its 4060 patients with AF into normal (BMI, 18.5-25 kg/m2), overweight (BMI, 25-30 kg/m2), and obese (BMI, >30 kg/m2) categories, per the convention at the time. It concluded that "[o]bese patients with atrial fibrillation appear to have better long-term outcomes than nonobese patients."

Bleeding Risk on Oral Anticoagulants

Also noteworthy in the current analysis is that variation in BMI did not seem to affect mortality or risk for major bleeding or nonhemorrhagic stroke according to choice of oral anticoagulant, whether a new oral anticoagulant (NOAC) or a vitamin K antagonist (VKA).

"We saw that even in the obese and extremely obese group, all-cause mortality was lower in the group taking NOACs compared with taking warfarin," Camm observed, "which goes against the idea that we would need any kind of dose adjustments for increased BMI."

Whereas the benefits of NOACs compared with VKA seem similar for patients with a BMI of 30 or 34 kg/m2 compared with a BMI of 23 kg/m2, for example, "none of the studies have many people with 50 BMI." Many clinicians "feel uncomfortable giving the same dose of NOAC to somebody who has a 60 BMI," he said. At least with warfarin, "you can check the [international normalized ratio]."

The current analysis included 40,482 patients with recently diagnosed AF and at least 1 other stroke risk factor from among the registry's more than 50,000 patients from 35 countries, enrolled from 2010 to 2016. They were followed for 2 years.

The 703 patients with BMI lower than 18.5 at AF diagnosis were classified per World Health Organization definitions as underweight, the 13,095 with BMI 18.5 to less than 25 kg/m2 as normal weight, the 15,043 with BMI 25 to less than 30 kg/m2 as overweight, the 7560 with BMI 30 to less than 35 kg/m2 as obese, and the 4081 with BMI at least 35 kg/m2 as extremely obese. Their ages averaged to 71 years, and 55.6% were men.

BMI Effects on Different Outcomes

Relationships between BMI and all-cause mortality and between BMI and new or worsening HF emerged as U-shaped, with the risk climbing with both increasing and decreasing BMI. The nadir BMI for risk was about 30 kg/m2 in the case of mortality and about 25 kg/m2 for new or worsening HF.

The all-cause mortality risk rose by 32% for every 5 BMI points lower than a BMI of 30 kg/m2, and by 16% for every 5 BMI points higher than 30 kg/m2, in a partially adjusted analysis. The risk for new or worsening HF rose significantly with increasing but not decreasing BMI, and the reverse was observed for the endpoint of major bleeding.

Adjusted Hazard Ratios (95% CI) for Outcomes per 5 kg/m2 Change in BMI, Above and Below Risk Nadir

Adjusted Hazard Ratios (95% CI) for Outcomes per 5 kg/m2 Change in BMI, Above and Below Risk Nadir

End points

Model 1a

Model 2b

BMI separation

<30 kg/m2

≥30 kg/m2

<30 kg/m2

≥30 kg/m2

All-cause mortality

1.32 (1.25-1.40)

1.16 (1.09-1.23)

1.39 (1.31-1.47)

1.04 (0.98-1.12)

Major bleeding

1.12 (1.01-1.26)

1.10 (0.97-1.24)

1.17 (1.04-1.31)

1.07 (0.95-1.22)

BMI separation

<25 kg/m2

≥25 kg/m2

<25 kg/m2

≥25 kg/m2

New, worsening HF

1.12 (0.96-1.32)

1.23 (1.14-1.33)

1.15 (0.99-1.36)

1.18 (1.09-1.29)

aModel 1: adjusted for age, sex, ethnicity, smoking status, alcohol use, and moderate to severe chronic kidney disease

bModel 2: further adjusted for hypertension, HF, diabetes, vascular disease, prior cerebrovascular event or system embolism, history of bleeding, and baseline anticoagulation

The effect of BMI on all-cause mortality was "substantially attenuated" when the analysis was further adjusted with "likely mediators of any association between BMI and outcomes," including hypertension, diabetes, HF, cerebrovascular events, and history of bleeding, Camm said.

That blunted BMI-mortality relationship, he said, "suggests that a lot of the effect is mediated through relatively traditional risk factors like hypertension and diabetes."

The 2010 AFFIRM analysis by BMI, Dr Lavie noted, "didn't even look at the underweight, they actually threw them out." Yet such patients with AF, who tend to be extremely frail or have chronic diseases or conditions other than the arrhythmia, are common. A take-home of the current study is that "the underweight with atrial fibrillation have a really bad prognosis."

Camm discloses research funding from the British Heart Foundation. Disclosures for the other authors are in the report. Dr Lavie has previously disclosed serving as a speaker and consultant for PAI Health and DSM Nutritional Products and is the author of The Obesity Paradox: When Thinner Means Sicker and Heavier Means Healthier.

Open Heart 2022. Published online August 6.

Study Highlights

  • Study data were drawn from the GARFIELD-AF patient registry, which enrolled 52,057 adults with AF older than 18 years from 35 countries between 2010 and 2016. All patients had at least 1 other risk factor for stroke.
  • The primary study outcomes of the study were mortality, nonhemorrhagic stroke or systemic embolism, new or worsening heart failure, and major bleeding. The primary variable was BMI.
  • 40,482 participants provided data for study analysis. The median age of participants was 71.0 years, and 55.6% were men.
  • 703 participants were underweight, 7560 were obese, and 4081 participants had a BMI of 35 kg/m2 or more.
  • Higher BMI was associated with younger age and a history of diabetes and vascular disease. Participants who were underweight were less likely to receive anticoagulation at baseline.
  • During more than 2 years of follow-up, 6.9% of the cohort died, 1.9% had a nonhemorrhagic stroke or systemic embolism, 1.5% had new or worsening heart failure, and 1.8% experienced major bleeding.
  • There was a U-shaped relationship between BMI and the risk for death. The lowest risk for all-cause mortality was at 30 kg/m2. The risk for death increased by 32% for each 5 kg/m2 decrease in BMI below that point, and it increased by 16% for each 5 kg/m2 increase above 30 kg/m2 as well.
  • The risk for major bleeding was elevated only among participants with a low BMI.
  • There was no association between the risk for stroke and BMI.
  • The use of novel oral anticoagulants was associated with a lower risk for mortality regardless of BMI.

Clinical Implications

  • A previous study found that short stature was an independent risk factor for stroke among adults with AF.
  • The current study demonstrates a U-shaped curve the association between BMI and mortality among older adults with AF. The lowest risk for mortality was noted among adults with a BMI of 30 kg/m2.
  • Implications for the healthcare team: The healthcare team should provide patient appropriate education targeted at modifiable risk factors with a goal of a healthy-range BMI.

 

Earn Credit