Objective: Studies in adults have found significant association between sleep disturbances and various medical symptoms/disorders. However, in children, few studies have explored this complex association in clinical samples. In this study, we examined prevalence of medical complaints in children with insomnia symptoms in a large general population of school aged children.
Methods: We conducted a cross sectional study of 700 children, ages 5-12 years, from the Penn State Children's Cohort. All children underwent a medical and psychiatric history, physical examination, 9-h overnight polysomnography, and neuropsychological testing. Comprehensive sleep and development questionnaires were completed by a parent. We compared 135 (19.3%) children with parent-reported sleep disturbances to 565 (80.7%) children with no parent-reported sleep disturbances.
Results: Insomnia symptoms were significantly associated with gastrointestinal regurgitation and headaches after controlling for demographic variables, apnea hypopnea index, ADHD, learning disorder or other psychiatric/behavioral disorder, socioeconomic status, and minority status. Children with gastrointestinal regurgitation and headaches compared to children without these symptoms were 3.3 times and 2.3 times as likely to suffer from sleep disturbances, respectively. Objectively, sleep latency increased in the sleep disturbance group, and there were significant differences between groups in REM latency, slow wave, and stage 2 sleep.
Discussion: These results underscore the importance of inquiring about insomnia symptoms when children present with medical complaints particularly gastrointestinal regurgitation or headaches and taking a comprehensive medical history when children present with sleep complaints. Future studies are needed to replicate these findings and explore the possible underlying pathophysiological abnormalities of such comorbidity between insomnia symptoms and medical symptoms in children.