Deadly Combination: Thin with belly fat
For people with heart disease, waist size may better predict risk of early death than overall weight, a new study finds.Researchers found that normal-weight heart patients who have belly fat have worse survival odds than obese people whose excess pounds are concentrated in their thighs and buttocks.
The findings suggest that heart doctors should consider weight distribution rather than simply body mass index (BMI) -- a measurement based on height and weight -- when assessing a patient's risk, the study authors say.
"Among people with coronary disease, those with the highest mortality are actually those with normal weight who have a central distribution of fat," said lead researcher Dr. Francisco Lopez-Jimenez, a professor of medicine at the Mayo Clinic in Rochester, Minn.
"In people with heart disease, BMI is a terrible way to assess risk," he added.
Fat that accumulates around the belly -- called visceral fat -- is a known risk factor for heart disease. Visceral fat changes how cholesterol is metabolized, increases blood pressure and puts people at risk for diabetes, he explained.
"If someone has extra fat in the belly and a normal BMI, this individual will most likely have a low amount of muscle mass," Lopez-Jimenez added. This suggests that although thin, these people aren't fit.
For the report, released online Jan. 28 in advance of print publication in an upcoming issue of the Journal of the American College of Cardiology, investigators pooled data from five studies that included more than 15,000 patients. Their average age was 66.