Poor sleep quality associated with obesity in men

Objective: The objective of this study is to examine the association between sleep quality and obesity status. Methods: A cross-sectional study of 3225 Chinese participants aged 18 to 65 years was conducted in Beijing in 2007. Body mass index (BMI) was classified according to the Working Group on Obesity in China, and sleep quality was assessed by the modified Pittsburg Sleep Quality Index questionnaire. Logistic regression models were applied to estimate the odds ratios (OR) and 95 % CIs of obesity by sleep quality adjusted for potential confounders. Two sets of potential confounders were used in the adjusted models. Model 1 was adjusted for sex and age. Model 2 was further adjusted for education level, occupation, marriage status, smoking, alcohol consumption, body pain, and health status. Results: Poor sleep quality was significantly negatively associated with overweight/obesity in men but not in women. Additional adjustment for education level, occupation, marriage status, smoking, alcohol consumption, body pain, and health status did not attenuate the association (OR = 1.41 with 95 % CI 1.03–1.93; P < 0.05) among men. The adjusted OR per sleep quality score hour was 1.07 (1.01–1.14) for overweight/obesity, suggesting that for one score increase in sleep quality, obesity/overweight risk increased by 7 % in men. Conclusion: Sleep quality was negatively associated with overweight/obesity in Chinese men but not in women.