Determinants of sleep problems in children with intellectual disability.

Children with intellectual disabilities are more likely to experience sleep disorders of insomnia, excessive daytime sleepiness and sleep breathing disorders than typically developing children. The present study examined risk factors for these sleep disorders in 447 children (aged 5-18 years), diagnosed with an intellectual disability and comorbid autism spectrum disorder, cerebral palsy, Down syndrome or Rett syndrome. Primary caregivers reported on their child's sleep using the Sleep Disturbance Scale for Children (SDSC), as well as medical comorbidities and functional abilities. Multivariate linear and logistic regressions were used to examine the effects of these factors on SDSC t scores and a binary indicator, respectively for the relevant subscales. Receiving operating characteristic curves were generated for each logistic regression model to determine their ability to discriminate between poor and good sleep. Comorbidities rather than functional abilities were associated with poorer sleep. In particular, recurrent pain, frequent seizures, frequent coughing, constipation and prescription of sleep medications were associated with abnormal sleep across the entire sample, but predictors differed between diagnostic groups. The present study suggests that comorbidities are more strongly associated with quality of sleep than functional impairments. The present study provides new information on potential associations between frequent coughing, prescription sleep medications and sleep quality that should be further investigated.