The association of irregular sleep habits with the risk of being overweight/obese in a sample of Portuguese children aged 6-9 years

ObjectivesThe consequences of irregular sleep duration at younger ages remains uncertain, especially when we consider shorter and longer than recommended sleep durations. Therefore, the present study aimed to analyze the association between healthy sleep duration and risk of obesity in Portuguese children. MethodsThe sample for this cross-sectional study comprised 8273 children (4183 females) aged 6-9 years. Height and weight were measured and body mass index (BMI) was calculated. Sleep habits and sedentary behaviors (i.e., TV viewing) were assessed by questionnaire. Logistic regressions were used. ResultsAfter adjustments for confounders, males who have irregular sleep duration were 1.28 times more likely to be classified as overweight or obese than their counterparts who had normal sleep duration on weekdays. No associations between sleep duration and overweight/obesity risk were found for girls, neither on weekdays nor on the weekend. For both boys and girls, the final model showed a significant inverse association between overweight/obesity risk and the educational level of fathers (males: 95% CI 0.51 to 0.79, P<.001; females: 95% CI 0.57 to 0.87, P<.01). ConclusionFindings revealed that shorter and longer than recommended sleep duration was positively associated with risk of obesity in boys on weekdays. Furthermore, pediatric obesity risk could be highly influenced by the education level of fathers of both males and females. Future research should extend a similar design, using objective measures of sleep duration to confirm some of the afore-mentioned results.