Indices of central and general obesity and cardiometabolic risk among adolescents in three ethnic groups in north-west China

Abstract

Background: ‘A Body Shape Index-Adolescents’ (ABSI-Adolescents) and waist-to-height ratio are recently proposed indices that quantify central obesity in adolescents.Aims: To investigate the scaling exponents to standardise waist circumference (WC) for body mass index (BMI) and height and to investigate the association between BMI, WC-based indices and cardiometabolic outcomes in adolescents of three ethnic groups.Subjects and methods: A cross-sectional study of 1755 adolescents (516 Hans, 565 Uygurs, 674 Kazakhs) was conducted in north-west China. Correlation between indices of obesity and blood pressure (BP) and fasting blood glucose (FBG) were estimated and compared.Results: Two ethnic groups (Han and Kazakh) had WC-BMI-height profiles different from the previously proposed ABSI-Adolescents and, therefore, required different scaling exponents for WC standardization. After adjustment for age and gender, WC and BMI have similar associations with BP and FBG. After further adjustment for BMI, WC remained significantly associated with FBG in all three ethnic groups (each p < 0.01) and with BP in Han and Kazakh adolescents (each p < 0.05).Conclusion: Body proportionality varied between the ethnic groups. WC and WC-based indices were associated with blood pressure and fasting blood glucose in adolescents of three ethnicities. The WC-based indices did not out-perform WC per se.