Thoracic-to-hip circumference ratio as a novel marker of type 2 diabetes, independent of body mass index and waist-to-hip ratio, in Korean adults

Aims: We compared upper trunk anthropometric indices with overall and central obesity indicators to predict the presence of type 2 diabetes in middle-aged and elderly Korean individuals. Methods: This cross-sectional investigation included 4079 rural and urban participants aged 40-80 years. Neck, thoracic, waist (WC), and hip circumferences were measured by a reliable and standardized method. The neck-to-hip ratio, the thoracic-to-hip ratio (THR), and the waist-to-hip ratio (WHR) were calculated. A 75-g oral glucose tolerance test was performed. Type 2 diabetes was defined based on the guidelines of the World Health Organization (1999). Results: The receiver operator characteristic curve analysis indicated that THR and WHR were better than body mass index (BMI) and other anthropometric indices at predicting the presence of type 2 diabetes. The adjusted odds ratios (OR) across quartiles of THR were slightly higher than the ORs for WHR, particularly in the highest quartile (odds ratios and 95% CI: 2.11 (1.47-3.04) versus 1.95 (1.37-2.77) in men; 3.40 (2.18-5.31) versus 2.31 (1.48-3.60) in women). The associations of THR and WHR with type 2 diabetes remained significant, despite a slight attenuation after a multivariate adjustment for BMI. The joint effect of BMI and THR on the risk of type 2 diabetes was larger than that of BMI and WHR. Conclusions: THR may be a novel marker of type 2 diabetes, particularly in women, and its association with diabetes was independent of BMI and WHR.