Prevalence of insomnia symptoms in a general population sample of young children and preadolescents: Gender effects

Objective: Our population-based study examined the prevalence of insomnia symptoms and its sociodemographic, subjective, and polysomnographic (PSG) sleep risk factors in young and preadolescent children. Methods: We performed a cross-sectional study of 700 children, ages 5-12 years who underwent a 9-h PSG and parent-completed sleep and development questionnaires (Penn State Child Cohort). Insomnia symptoms were defined as parent report of difficulty falling or staying asleep and sleep-disordered breathing (SDB) as an apnea hypopnea index of ≥1. Results: The prevalence of insomnia symptoms was 19.3% and did not significantly change (20.2%) when children with SDB were excluded. A significant interaction between gender and age revealed that the prevalence of insomnia symptoms was highest in girls ages 11 to 12 years (30.6%). This gender difference was not associated with significant differences between girls and boys ages 11-12. years in anxiety and depressive symptoms. In contrast girls ages 11-12. years with insomnia symptoms, but not boys of the same group, demonstrated clinically significant PSG sleep disturbances compared to those without insomnia symptoms. Conclusions: These data suggest that one out of five young children and preadolescents of the general population have insomnia symptoms. Importantly, the prevalence of insomnia symptoms peaks in girls ages 11 to 12 years and is associated with objective sleep disturbances which may be related to hormonal changes associated with the onset of puberty rather than anxiety and depression.