Associations of Sleep Duration and Screen Time with Incidence of Overweight in European Children: The IDEFICS/I. Family Cohort

oduction: Over the past decades, children have been increasinglyusing screen devices, while at the same time theirsleep duration has decreased. Both behaviors have been associatedwith excess weight, and it is possible they act asmutually reinforcing behaviors for weight gain. The aim ofthe study was to explore independent, prospective associationsof screen time and sleep duration with incident overweightin a sample of European children. Methods: Datafrom 4,285 children of the IDEFICS/I.Family cohort who werefollowed up from 2009/2010 to 2013/2014 were analyzed.Hours per day of screen time and of sleep duration were reportedby parents at baseline. Logistic regression analyseswere carried out in separate and mutually adjusted modelscontrolled for sex, age, European country region, parentallevel of education, and baseline BMI z-scores. Results:Among normal weight children at baseline (N = 3,734), separatemodels suggest that every hour increase in screen timeand every hour decrease in sleep duration were associatedwith higher odds of the child becoming overweight or obeseat follow-up (OR = 1.16, 95% CI: 1.02-1.32 and OR = 1.23, 95%CI: 1.05-1.43, respectively). In the mutually adjusted model,both associations were attenuated slightly ( screen timeOR = 1.13, 95% CI: 0.99-1.28; sleep duration OR = 1.20, 95%CI: 1.03-1.40), being consistently somewhat stronger forsleep duration. Discussion/Conclusion: Both screen timeand sleep duration increased the incidence of overweight orobesity by 13-20%. Interventions that include an emphasison adequate sleep and minimal screen time are needed toestablish their causal role in the prevention of overweightand obesity among European children.