A community-based study of insomnia in Hong Kong Chinese children: Prevalence, risk factors and familial aggregation

ObjectivesThere has been limited data on familial aggregation of insomnia. We aimed to explore the prevalence, risk factors and familial aggregation of childhood insomnia with a large community-based sample.MethodsA community-based epidemiologic study of sleep disorders was conducted among primary school children. Those children with at least one reported biological parent were recruited. A total of 5695 children (mean age 9.2; SD 1.8), 4939 of their reported biological mothers (mean age 38.9; SD 4.6) and 4289 of their reported biological fathers (mean age 43.3; SD 5.5) were studied.ResultsThe rates of insomnia ⩾3 times/week in the past 12 months were 4.0%, 12.8% and 9.7% for children, mothers and fathers, respectively. A robust familial aggregation of insomnia was found even after adjustment of the shared environmental and socio-demographic factors. There was a significant dose–response relationship among the children across their parental status from neither, fathers, mothers to both parents with insomnia [3.0%, 7.1%, 9.5% and 11.9%; with ORs (95% CIs) = 2.48 (1.82–4.37) for fathers, 3.42 (2.55–4.59) for mothers and 4.42 (2.42–8.10) for both parents, respectively]. In addition, the frequency of insomniac symptoms of the parents also had a dose–response effect on the rate of insomnia of their children.ConclusionsInsomnia is a common problem in both children and their parents. A significant familial aggregation of childhood onset insomnia was seen in this study even after adjustment of the co-risk factors. There was a dose–response effect of parental insomnia on the rate of insomnia of their children with a slight predilection of maternal influences.