Sleep duration and risk of obesity: A genome and epidemiological study

Abstract

Obesity is one of the risk factors for metabolic and cardiovascular diseases. Although numerous epidemiological studies have reported a possible causal association between sleep duration and the risk of obesity, evidence for an associa- tion in adults remains unclear. Accordingly, the present study aimed to evaluate the association between sleep duration and the risk of obesity in an adult group. To this end, 5,719 adults (2,876 males and 2,843 females) who participated in a genome and epidemiology study, were analyzed. Data were obtained on sleep duration, body mass index (BMI) and other demographic data including age, sex, waist circumference, alcohol consumption and smoking status. The association between sleep duration and obesity was investigated using a Chi-squared test or logistic regression analysis. Multivariate logistic regression analysis revealed that a short sleep duration (≤6 h) was significantly associated with obesity after adjus- ting for various confounding factors (OR, 1.446; 95% CI, 1.254-1.667; P<0.0001). Strong associations between a short sleep duration (≤6 h) and obesity were identified in males (OR, 1.567; 95% CI, 1.258-1.953; P<0.0001) and the early midlife group (OR, 1.584; 95% CI, 1.320-1.902; P<0.0001). Furthermore, the risk of obesity significantly increased with a short sleep duration (≤6 h) in participants without hyperten- sion (OR, 1.534; 95% CI, 1.263-1.863; P<0.0001) or diabetes (OR, 1.473; 95% CI, 1.272-1.705; P<0.0001). A short sleep duration was positively related to a high prevalence of obesity, and this association varied with sex, age, and the presence of metabolic disease. On the whole, the findings of the present study provide evidence that sleep duration can affect obesity.