Article Text
Abstract
Introduction An association between sleep duration and overweight has been reported from several countries. Comparability of those results is limited by reasons of methodological differences. In a multi-center study we analysed this association in children from northern and southern Europe.
Objectives To investigate differences and a possible effect modification by geographical region in the association between sleep duration and overweight.
Methods In the IDEFICS-Study we examined 16.223 children (2–9 years) from eight European countries. Sleep was assessed by means of a parental 24h-Recall. Logistic regression models were applied to analyse the association between overweight and sleep duration and to test for effect modification by region.
Results A dose dependent association between sleep duration and overweight was seen. This persisted after adjustment, but remained significant only for sleeping <9h if stratified by region (north:OR 2.0; 99% CI 1.3 to 3.2 vs south:OR 2.5; 99% CI 1.4 to 4.3). No effect modification by region was found. The association was stronger in older children.
Conclusion Geographic region and related aspects do not modify the association between sleep and overweight, but should be taken in consideration as a confounding factor on this association.