Which obesity indicators are better predictors of metabolic risk?: Healthy twin study

No consensus exists as to the most sensitive and specific obesity indicator associated with metabolic risk factors. We aimed to validate anthropometry as the predictor for obesity-related metabolic risk factors through comparison with direct body composition measures in Korean adults. A total of 995 Korean women and 577 Korean men who participated in the Healthy Twin study were the subjects. Anthropometric measurements included BMI, waist circumference ( WC), waist-to-hip ratio ( WHR), and waist-to-height ratio ( WHTR). Direct body composition measures included the percentage of body fat (%BF) measured using dual-energy X-ray absorptiometry scanners and bioelectrical impedance analyzer ( BIA). The following criteria were used to define abnormal metabolic risk factors: blood pressure >= 130/ 85 mm Hg, fasting glucose (>= 100 mg/ dl), insulin (>= 25 mu U/ ml), homeostasis model assessment ( HOMA) (>= 2.61), high-density lipoprotein ( HDL) (< 40 mg/ dl for men or <50 mg/ dl for women), triacylglycerol (>= 150 mg/ dl), uric acid (> 7 mg/ dl for men or > 6 mg/ dl for women), high-sensitivity C-reactive protein ( hs-CRP) (>= 2.11 mg/ l). In multiple regression analyses ( adjusted for age, education, smoking, alcohol, exercise and past/ current medical history, and treated families as a random effect), WC, WHTR, and BMI were consistently associated with all metabolic risk factors regardless of the subject's gender. Some of the areas under the receiver-operating characteristic curves regarding abnormal metabolic risk factors were significantly higher for the three indicators of central obesity than for %BF. Our study validates the usefulness of anthropometry over direct body fat measures to predict metabolic risks.