Sleep disorders and behavioural problems among 8- to 11-year-old children
Question of the study: To assess the prevalence of sleep disorders in 8- to 11-year-old children and their relation to behavioural problems. Study design: A population based, cross-sectional survey was carried out among fourth-grade elementary school children in Cologne, Germany. A total of 8599 children were enrolled. Parent-completed and children-completed questionnaires were used to ascertain sleep disorders and behavioural problems. Results: In all, 4531 questionnaires were completed. Parent-reported sleep onset delays were frequent with 6% of the children, problems to sleep through the night with 3%, daytime sleepiness with 1%. Children-reported sleep onset delays were frequent with 10%, problems to sleep through the night with 6%, and daytime sleepiness with 3%. Children with these sleep disorders and daytime sleepiness had an increased risk of emotional problems, hyperactivity, conduct problems, peer problems, and social difficulties compared with children without sleep disorders or daytime sleepiness. Conclusions: Sleep disorders are common among 8- to 11-year-old children. To assess the prevalence of sleep disorders among school children, parent-completed and children-completed questionnaires are necessary. Sleep onset delays, problems to sleep through the night, and daytime sleepiness among children are associated with an increased risk of behavioural problems.