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 > or = 130/85 mm Hg, fasting glucose (> or = 100 mg/dl), insulin (> or = 25 microU/ml), homeostasis model assessment (HOMA) (> or = 2.61), high-density lipoprotein (HDL) (<40 mg/dl for men or <50 mg/dl for women), triacylglycerol (> or = 150 mg/dl), uric acid (>7 mg/dl for men or >6 mg/dl for women), high-sensitivity C-reactive protein (hs-CRP) (> or = 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.