The discriminatory performance of body mass index, waist circumference, waist-to-hip ratio and waist-to-height ratio for detection of metabolic syndrome and their optimal cutoffs among Iranian adults.

BACKGROUND: The superiority of either of body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR) for prediction of metabolic syndrome (MetS) is remained controversial in Asian population. The objective of this study was to compare the discriminative capacity of either of these measures in prediction of non-adipose components of MetS.

METHODS: In this population-based cross sectional study, 1000 representative samples of adults were recruited in Babol, northern Iran. The demographic, anthropometric measures and blood pressure were determined by standard method. Fasting plasma glucose (FPG), triglycerides (TG), total cholesterol (CHL), high density lipoprotein (HDL) cholesterol levels were measured with enzymatic methods by an auto analyzer. The presence of two or more any of four non-obese components were considered as MetS.

RESULTS: The diagnostic accuracies (AUCs) of four different measures were rather similar. While AUC for BMI (AUC=0.684; 95% CI: 0.633, 0.736) slightly tended to be higher than that of WC (AUC=0.640; 95% CI: 0.587, 0.693) and WHtR (AUC=0.649; 95% CI: 0.596, 0.701) in men but the accuracy of WC (equivalently WHtR (AUC=0.708; 95% CI: 0.664, 0.751) is tended to be greater than that of BMI in women. The optimal cut-off value for WC was higher in men compared with women.

CONCLUSIONS: Overall, BMI, WC and WHtR were significant predictors of MetS equally but WC (equivalently WHtR) was a better predictor than BMI and WHR in women. The optimal cut-offs of WC are lower compared with western population for men but not for women.