The six obesity indices, which one is more compatible with metabolic syndrome? A population based study.

OBJECTIVES: The present study was conducted to determine the best discriminators in the diagnosis of the metabolic syndrome (MetS) among six obesity indexes. Furthermore the optimal cutoff points for all obesity indexes were determined.

METHODS: The baseline data of 5910 subjects of Haraz cohort study which was conducted in northern Iran were analyzed. Receiver operating characteristic (ROC) analyses were separately performed to determine discriminatory power of six obesity indexes, including, body mass index (BMI), waist circumference (WC), waist to hip ratio (WHR), waist to height ratio (WHtR), abdominal volume index (AVI) and conicity index (CI) for diagnosis of at least two other components of MetS. Youden index was used to determine the optimal cutoff points.

RESULTS: While the optimal cutoff points in men were 26.0kg/m2 for BMI, 90cm for WC, 0.90 for WHR, 0.53 for WHtR, 16.6 (cm2 ) for AVI and 1.24(m32 /kg12 ) for CI, the optimal values in women were 29.0kg/m2 for BMI, 91cm for WC, 0.86 for WHR, 0.58 for WHtR, 17.0(cm2 ) for AVI and 1.23 (m32 /kg12 ) for CI. The prevalence of overweight or obesity was 46.1% to 54.1% in women and 49.5% to 53.6% in men based on various obesity indexes. The area under the ROC curves (AUCs) varied from 0.671(0.651-0.690) for CI to 0.718(0.700-0.736) for WC in men and from 0.668 (0.646-0.690) for BMI to 0.755(0.735-0.774) for WHR and CI in women.

CONCLUSION: Except for CI in men and BMI in women, other obesity indexes were good discriminator in the diagnosis of the MetS.