Obesity contributes to cardiovascular risk no matter where a person carries the weight, concluded researchers after looking at outcomes for nearly a quarter-million people worldwide.
Body-mass index, (BMI) waist circumference, and waist-to-hip ratio do not predict cardiovascular disease risk any better when physicians recorded systolic blood pressure, history of diabetes and cholesterol levels, researchers reported in The Lancet.
The research group used individual records from 58 prospective studies with at least one year of follow up. In each study, participants were not selected on the basis of having previous vascular disease. Each study provided baseline for weight, height, and waist and hip circumference. Cause-specific mortality or vascular morbidity were recorded according to well defined criteria.
Individual records included 221,934 people in 17 countries. In people with BMI of 20 kg/m2 or higher, hazard ratios for cardiovascular disease were 1.23 (95% CI, 1.17 to 1.29) with BMI, 1.27 (95% CI, 1.20 to 1.33) with waist circumference, and 1.25 (95% CI, 1.19 to 1.31) with waist-to-hip ratio, after adjustment for age, sex, and smoking status. After adjusting for baseline systolic blood pressure, history of diabetes, and total and HDL cholesterol, corresponding hazard rations were 1.07 (95% CI, 1.03 to 1.11) with BMI, 1.10 (95% CI, 1.05 to 1.14) with waist circumference, and 1.12 (95% CI, 1.08 to 1.15) with waist-to-hip ratio.
BMI, waist circumference, or waist-to-hip ratio did not importantly improve risk discrimination or predicted 10-year risk, and the findings remained the same when adiposity measures were considered.
"The main finding of this study does not, of course, diminish the importance of adiposity as a major modifiable determinant of cardiovascular disease," the authors wrote. "Rather, because excess adiposity is a major determinant of the intermediate risk factors noted above, our findings underscore the importance of controlling adiposity to help prevent cardiovascular disease."
Still, the authors said, adiposity remains an important measure in risk assessment to promote weight loss or in communicating the risks of obesity to patients.