Study: More Belly Weight Increases Danger of Heart Disease Even If BMI Does Not Indicate Obesity

April 27, 2021
Jill Murphy, Associate Editor

A greater understanding of obesity and its impact on cardiovascular health highlights abdominal obesity, sometimes referred to as visceral adipose tissue (VAT), as a cardiovascular disease risk marker.

People with abdominal obesity and excess fat around the body’s mid-section and organs have an increased risk of heart disease even if their body mass index (BMI) measurement is within a healthy weight range, according to a study published in Journals.

“This scientific statement provides the most recent research and information on the relationship between obesity and obesity treatment in coronary heart disease, heart failure and arrhythmias,” said Tiffany M. Powell-Wiley, MD, MPH, FAHA, chair of the writing committee and chief of the Social Determinants of Obesity and Cardiovascular Risk Laboratory in the Division of Intramural Research at the National Heart, Lung, and Blood Institute at the National Institutes of Health, in the press release. “The timing of this information is important because the obesity epidemic contributes significantly to the global burden of cardiovascular disease and numerous chronic health conditions that also impact heart disease.”

A greater understanding of obesity and its impact on cardiovascular health highlights abdominal obesity, sometimes referred to as visceral adipose tissue (VAT), as a cardiovascular disease risk marker. VAT is commonly determined by waist circumference, the ratio of waist circumference to height, or waist-to-hip ratio, which has been shown to predict cardiovascular death independent of BMI.

Experts recommend both abdominal measurement and BMI be assessed during regular health care visits because a high waist circumference or low waist-to-hip ratio, even in healthy weight individuals, could mean an increased risk of heart disease. Abdominal obesity is also linked to fat accumulation around the liver that often leads to non-alcoholic fatty liver disease (NAFLD), which adds to cardiovascular disease risk, according to the study.

“Studies that have examined the relationship between abdominal fat and cardiovascular outcomes confirm that visceral fat is a clear health hazard,” Powell-Wiley said in the press release.

The risk-inducing power of abdominal obesity is so strong that in people who are overweight or have obesity based on BMI, low levels of fat tissue around their midsection and organs could still indicate lower cardiovascular disease risks, also known as “metabolically healthy obesity,” according to the study.

For the report, experts analyzed research on managing and treating obesity, particularly abdominal obesity, finding that reducing calories can reduce abdominal fat and that aerobic exercise is the best physical activity to reduce abdominal obesity.

Further, meeting the current recommendations of 150 minutes per week of physical activity may be sufficient to reduce abdominal fat with no additional loss from longer activity times. Exercise or a combination of dietary change and physical activity has been shown in some instances to reduce abdominal obesity even without weight loss, according to the study.

Lifestyle changes and subsequent weight loss improve blood sugar, blood pressure, triglyceride and cholesterol levels, and reduce inflammation, improve blood vessel function, and treat NAFLD. However, studies of lifestyle change programs have not shown a reduction in coronary artery disease events, such as heart attack or chest pain.

Bariatric surgery for weight loss treatment is associated with a reduction in coronary artery disease risk compared to non-surgical weight loss. The difference may be attributed to the larger amount of weight loss and the resultant changes in metabolism that are typical after bariatric surgery, according to the study authors.

“Additional work is needed to identify effective interventions for patients with obesity that improve cardiovascular disease outcomes and reduce cardiovascular disease mortality, as is seen with bariatric surgery,” Powell-Wiley said.

The study authors also note that people with overweight or obesity are often screened earlier for cardiovascular disease than people with healthy weight, resulting in earlier diagnoses and treatment.

“The underlying mechanisms for the obesity paradox remain unclear,” Powell-Wiley said in the press release. “Despite the existence of the paradox for short-term cardiovascular disease outcomes, the data show that patients with overweight or obesity suffer from cardiovascular disease events at an earlier age, live with cardiovascular disease for more of their lives and have a shorter average lifespan than patients with normal weight.”

The report identifies many areas for future research, including a call for further study of lifestyle interventions that may be most effective in decreasing visceral adiposity and improving cardiovascular outcomes.

“It’s important to understand how nutrition can be personalized based on genetics or other markers for cardiovascular disease risk,” Powell-Wiley said in the press release.

She added that as overweight and obesity prevalence increases among adolescents worldwide, it is critical to address how best to develop upstream primary prevention interventions and better treatment strategies, particularly for young patients with severe obesity.

REFERENCE

More belly weight increases danger of heart disease even if BMI does not indicate obesity. American Heart Association. Published April 22, 2021. Accessed April 22, 2021. https://newsroom.heart.org/news/more-belly-weight-increases-danger-of-heart-disease-even-if-bmi-does-not-indicate-obesity