Characteristics of sleep in children with autism spectrum disorders from the Simons Simplex Collection

Abstract Background An estimated 40–80% of children with ASD have sleep problems, including bedtime behavior problems, difficulty falling asleep and staying asleep, decreased sleep time, and daytime sleepiness. This study aimed to examine the relationship between sleep problems and characteristics of children with ASD in a large, nationwide sample. Methods This secondary analysis of children 4- to 18-years explored 11 sleep problems using the Simons Simplex Collection Sleep Interview (SSCSI). The SSCSI includes nighttime problems, daytime problems, and sleep duration problems subscales. Chi square, Kruskal-Wallis and Mann- Whitney U tests were performed to detect differences between age groups, sexes, and sleep problem groups (none/minimal, mild, moderate/severe). Odds ratios for variables associated with sleep problems were assessed using baseline and adjacent category logistic regression. Two-way interaction effects were included in regression models, and stratified analyses were performed for age groups. Results Approximately 41% of children were categorized as having mild or moderate/severe sleep problems. The most commonly reported SSCSI items were in the nighttime problems subscale; difficulty falling asleep was the most frequently reported item. Mean sleep duration was approximately 9 h, although more than one-quarter slept less than the hours recommended for their age. Increased odds of sleep problems were most frequently associated with gastrointestinal distress (GID) and non-verbal IQ (NVIQ), followed by male sex and age. ADOS severity score is likely not associated with sleep problems in this sample. Conclusions This study advances our understanding of sleep in ASD by showing that GID, NVIQ, sex, and age increased the odds of sleep problems in children with ASD. These results reinforce that healthcare professionals should screen for sleep problems in children with ASD and suggest future lines of inquiry.