Associations of three thermogenic adipokines with metabolic syndrome in obese and non-obese populations from the China plateau: the China Multi-Ethnic Cohort

OBJECTIVES: High altitude exposure decreases the incidence of obesity and metabolic syndrome, but increases the expression of the thermogenic adipokines (leptin, fat cell fatty acid-binding protein (A-FABP) and visfatin). This study investigated the correlation of these adipokines with obesity and metabolic syndrome (MetS) in populations residing in a plateau-specific environment. DESIGN: Case–control study. SETTING: We cross-sectionally analysed data from the China Multi-Ethnic Cohort. PARTICIPANTS: A total of 475 obese (OB, body mass index (BMI)≥28.0 kg/m(2)) plateau Han people and 475 age, sex and region-matched non-obese (NO, 18.5≤BMI<24.0 kg/m(2)) subjects were recruited. MetS was defined according to the National Cholesterol Education Program Adult Treatment Panel III guidelines. PRIMARY AND SECONDARY OUTCOME MEASURES: Data with normal distributions were expressed as the mean (Stanard Deviation, SD), and data with skewed distributions were expressed as the median (Interquartile Range, IQR). The participants were grouped and the rank-sum test, χ(2) test or t-tests was used for comparing groups. Spearman correlation coefficients were estimated to assess the relationships among leptin, A-FABP, visfatin and the components of MetS in each group. RESULTS: A-FABP was an independent predictor of OB (OR, 1.207; 95% CI, 1.170 to 1.245; p<0.05), ABSI (OR, 1.035; 95%CI, 1.019 to 1.052; p<0.05) and MetS (OR, 1.035; 95% CI, 1.013 to 1.057; p<0.05). Leptin was an independent predictor of MetS in the NO group. Visfatin was an independent predictor of increased ABSI, but not for OB or MetS. CONCLUSION: An abnormally elevated plasma A-FABP level, but not leptin or visfatin is a potential risk factor for MetS in high-altitude populations.