How To Measure Weight Gain By Paula Rasich Reviewed by Elizabeth Klodas, MD, FACC (CardioSmart) August 22, 2008--You already know that being overweight raises your heart disease risk, but you may be confused about the ideal way to calculate that risk.

Research has suggested that visceral fat, also known as belly bulge, is an even more potent risk factor than weight alone. But according to new research, excess pounds are not good for your heart--- no matter how they add up.

In a study of more than 49,000 people, Tobias Kurth, MD, ScD, an assistant professor of medicine and an associate epidemiologist at Brigham and Women’s Hospital in Boston, and colleagues reviewed data from two large-scale studies, the Physicians’ Health Study and the Women’s Health Study. In this analysis, researchers compared body mass index (BMI) and measures of abdominal fat that included waist-to-height ratio (WHtR), waist circumference and waist-to-hip ratio with risk of cardiovascular disease.

The findings showed that WHtR was the strongest predictor of who was at increased risk of heart attack, stroke and death. But when researchers compared WHtR to BMI (the commonly used measure of weight corrected for height), they discovered only a small difference in risk. In addition, researchers were able to classify people into higher and lower cardiovascular risk groups regardless of which measure they used.

“It actually doesn’t matter how you measure obesity, the important message is that obesity is a risk factor for cardiovascular disease.” says Kurth. “Our data showed that the difference between the measures was not clinically consequential.”

In a second study of nearly 1,400 people, ages 21 to 74, a team of researchers led by Christina C. Wee, MD, of Beth Israel Deaconess Medical Center in Boston examined data from the Post CABG (Coronary Artery Bypass Graft) trial, a multicenter study of patients who had undergone bypass surgery.  To assess the buildup of plaque on artery walls, angiography was performed on participants at the start of the investigation and again five years later. An important finding was that a higher BMI was strongly associated with the progression of blockages over time. 

What’s the bottom line? “The BMI has been used for many years, and will remain the most clinically practical measure because it is the most user-friendly,” says Kurth. 

The results of these studies are published in the August 19, 2008 issue of the Journal of the American College of Cardiology.

Sources:

Gelber RP et al.  Measures of Obesity and Cardiovascular Risk Among Men and Women.  Journal of the American College of Cardiology, August 2008.

Wee CC et al. The Relationship Between Obesity and Atherosclerotic Progression and Prognosis Among Patients with Coronary Artery Bypass Grafts: The Effect of Aggressive Statin Therapy.  Journal of the American College of Cardiology, August 2008.

Tobias Kurth, MD, ScD, Assistant Professor of Medicine, Harvard Medical School, and Associate Epidemiologist at Brigham and Women’s Hospital, both in Boston, MA.