Body mass index, waist-to-hip ratio and cognitive function among Chinese elderly: a cross-sectional study

OBJECTIVES: To investigate the associations between body mass index (BMI), waist-to-hip ratio (WHR) and cognitive function among Chinese elderly. DESIGN: Cross-sectional study. SETTING: Community. PARTICIPANTS: Data were obtained from the baseline survey of a community-based cohort in Zhejiang Province, and 9326 persons aged 60 years and older were enrolled. PRIMARY OUTCOME MEASURES: We investigated the association between BMI and cognition, and then explored the association between WHR and cognition across different quartiles of BMI. RESULTS: A sample of 9087 persons was used in this study, including 4375 men and 4712 women. Higher WHR increased cognitive impairment risk in those with BMI >25.3 kg/m(2) (OR (per 0.1 increase) 1.39; 95% CI 1.13 to 1.70). No statistically significant association was found in other BMI categories. CONCLUSIONS: Higher WHR could increase the risk of cognitive impairment among elderly with BMI >25.3 kg/m(2). Our results suggest that it could be of benefit to the elderly with high BMI to control WHR.