March 10, 2011 -- For years, people with a so-called "pear" shape have breathed easier than people with an ''apple'' shape because of their presumed lower risk for heart attack and stroke.
Experts believed that people with apple-shaped obesity, also called central obesity because of excess fat in the belly, had a higher risk for cardiovascular disease than people who are pear-shaped, with excess fat on the hips and buttocks.
Not so, according to a large new study that followed more than 220,000 people in 17 countries.
''Previous studies were suggesting that central obesity was worse compared to general obesity," researcher Emanuele Di Angelantonio, MD, PhD, lecturer at the University of Cambridge, U.K., tells WebMD. ''Actually, this study shows that the two are the same in terms of cardiovascular risk."
“Obesity is an important driver for cardiovascular disease, whatever form it is," he says.
The various measures used to assess obesity -- such as body mass index or BMI, waist circumference, and waist-to-hip ratio -- all perform similarly when used to assess cardiovascular risk, the researchers found.
Obesity and Heart Disease: Focusing on the Prediction Debate
Over the years, guidelines from national and international organizations such as the National Heart, Lung, and Blood Institute and the World Health Organization have recommended a variety of measures to predict a person's risk of cardiovascular disease.
These recommendations include the obesity measures such as BMI, along with screening tests such as cholesterol, and taking into account other risk factors.
"There has been a lot of controversy" about which recommendation is best, Di Angelantonio tells WebMD.
So Di Angelantonio and his colleagues from the Emerging Risk Factors Collaboration evaluated the medical records of 221,934 men and women in 17 countries who had participated in 58 studies.
A majority, 70%, had data available on common risk factors such as smoking status, systolic blood pressure (the upper number), diabetes history, and cholesterol (total and HDL or "good" cholesterol).
Their objective was to analyze individual data and produce reliable estimates of the association of BMI, waist circumference, and waist-to-hip ratio with the onset of cardiovascular disease -- including coronary heart disease, cardiovascular disease, or stroke.
Participants were free of cardiovascular problems at the study start. They were, on average, 58 years old when the studies started and resided in Europe, North America, Australia, and Japan. Each was monitored for nearly a decade.
During the follow-up, there were 14,297 cardiovascular events.