Cutoff point of waist circumference for the diagnosis of metabolic syndrome in an Iranian population.

BACKGROUND: Proposed cutoffs for waist circumference (WC) in western populations may be not appropriate for Asian populations. The published data among Iranians are insufficient to address this issue. This study was designed to identify cutoffs for WC that confer increased risk of metabolic syndrome in Iranian adults living in Zanjan, a province located in the west of Tehran. MATERIALS AND METHODS: Data of a cross-sectional sample of 3277 Iranian adults aged more than 20 years were analyzed. In the original study individual body weight, height, WC, and blood pressure were assessed and fasting plasma glucose, triglycerides, total cholesterol, low- and high-density lipoprotein cholesterol were measured. After excluding WC, existence of two or more of the remaining four risk factors of the modified NCEP III criteria for metabolic syndrome were defined as multiple risk factors. Receiver operating characteristic (ROC) analysis was used to find out the optimal cutoff values of WC to predict metabolic syndrome. RESULTS: The cutoff level yielding the maximal sensitivity and specificity for predicting the presence of metabolic syndrome (multiple risk factors) was 87 cm in men and 82 cm in women. Cutoffs corresponding to body mass index (BMI) 25 and 30 kg/m(2) to predict metabolic syndrome were 84 and 97 cm in men and 78 and 91 cm in women, respectively. CONCLUSIONS: Lower cutoffs for WC should be considered in the identification of Iranian population at high risk of metabolic syndrome.