Objectives: A growing trend in childhood sleep habits is to compensate for the weekday sleep deficit by longer weekend and holiday sleep duration. We aimed to investigate the effect of weekend/holiday sleep compensation in relation to childhood overweight and obesity.
Methods: This is a community-based cross-sectional study with 5159 children (49.6% boys), mean age of 9.25 years (SD: 1.78), from 13 primary schools in Hong Kong. Data on sleep patterns, lifestyle, body weight, and height of children were obtained from questionnaires. Sleep durations during weekdays, weekends, and holidays were predictor variables. BMI z scores and obesity/overweight status were the outcome measures.
Results: Children slept significantly longer during holidays (mean [SD]: 10.20 (0.92) hours) and weekends (school terms) (10.07 [0.93] hours) than during school weekdays (9.18 [0.95] hours). Children with shorter sleep duration had higher BMI z scores regardless of the sleep parameters used in the analysis. Among children who slept <8 hours during weekdays, those children who did not compensate for their sleep deficit during weekends or holidays had significantly increased risk of overweight/obesity compared with those children with sleep compensation (odds ratios: 2.59 [95% confidence interval: 1.22-5.48] and 2.32 [95% confidence interval: 1.00-5.53], respectively).
Conclusions: There was a prominent difference in sleep duration between weekdays and weekends/holidays among school children. Short sleep duration was associated with higher BMI, but compensation of sleep during weekends/holidays may partly ameliorate the risk of childhood overweight/obesity. Further prospective and interventional study is needed to delineate the risk-benefit effect of these increasingly common sleep habits among children and adolescents.