Short sleep duration is independently associated with overweight and obesity in Quebec children

Objective: To investigate the association of sleep duration with adiposity and to determine if caloric intake and physical activity mediate this relationship. Methods: The Quebec Adiposity and Lifestyle Investigation in Youth (QUALITY) study is an ongoing longitudinal investigation of Caucasian children with at least one obese biological parent. Children (n=550) with an average age of 9.6 years (SD=0.9) who provided complete data at baseline were included in the cross-sectional analyses. Objective measures of adiposity (BMI Z-score, waist circumference, percent body fat measured by dual-energy X-ray absorptiometry), sleep duration and physical activity (accelerometer over 7 days), and diet (24-hour food recalls) were collected. Children were categorized into 4 groups according to sleep duration: <10 hours, 10-10.9 hours, 11-11.9 hours, and ≥12 hours of sleep per night. Results: We observed a U-shaped relationship between sleep duration and all adiposity indices. None of energy intake, snacking, screen time or physical activity intensity differed significantly between sleep categories. After adjusting for age, sex, Tanner stage, highest educational level of the parents, total annual family income, and parental BMI, only short-duration sleepers (<10 hours) had an increased odds of overweight/obesity (OR 2.08, 95% CI 1.16-3.67). Addition of total energy intake and physical activity to the model did not change the association substantially (OR 2.05, 95% CI 1.15-3.63). Conclusion: The present study provides evidence that short sleep duration is a risk factor for overweight and obesity in children, independent of potential covariates. These results further emphasize the need to add sleep duration to the determinants of obesity.