Shorter sleep duration is associated with social impairment and comorbidities in ASD

Abstract

Sleep disturbance, particularly insomnia, is common in children with autism spectrum disorders (ASD). Furthermore, disturbed sleep affects core symptoms and other related comorbidities. Understanding the causes and consequences of sleep disturbances in children with ASD is an important step toward mitigating these symptoms. To better understand the connection between sleep duration and ASD severity, we analyzed ASD-related symptoms using the Autism Diagnostic Interview-Revised (ADI-R), Autism Diagnostic Observation Schedule (ADOS), IQ scores, and parent reports of the average amount of time slept per night that were available in the medical histories of 2,714 children with ASD in the Simons Simplex Collection (SSC). The mean (SD) sleep duration was 555 minutes. Sleep duration and severity of core ASD symptoms were negatively correlated, and sleep duration and IQ scores were positively correlated. Regression results indicated that more severe social impairment, primarily a failure to develop peer relationships, is the core symptom most strongly associated with short sleep duration. Furthermore, increased severity for numerous maladaptive behaviors assessed on the Child Behavior Checklist, as well as reports of attention deficit disorder, depressive disorder, and obsessive compulsive disorder were associated with short sleep duration. Severity scores for social/communication impairment and restricted and repetitive behaviors (RRB) were increased, and IQ scores were decreased, for children reported to sleep ≤420 minutes per night (lower 5th percentile) compared to children sleeping ≥660 minutes (upper 95th percentile). Our results indicate that reduced amounts of sleep are related to more severe symptoms in children with ASD. Autism Res 2017. © 2017 International Society for Autism Research, Wiley Periodicals, Inc. Autism Res 2017, 10: 1221-1238. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

Keywords: comorbid conditions; neurology; sleep (disorders); social cognition; subtypes (of ASD).

Figure 1.

Correlation between ASD-related symptom severity and sleep duration. Plotted are the linear predictions for the relationships between sleep duration in minutes with: (A) ADI-R Social Impairment Scores, (B) ADI-R Verbal Communication Impairment Scores, (C) ADI-R Nonverbal Communication Impairment Scores, (D) ADI-R Restricted and Repetitive Behavior Scores, (E) ADOS Social Affect Calibrated Severity Scores, (F) ADOS Restricted and Repetitive Behavior Calibrated Severity Scores, (G) Verbal IQ scores, and (H) Nonverbal IQ scores. 95% confidence intervals around fitted lines are indicated in gray; Spearman’s rank correlation coefficients (ρ) and the corresponding P-values are provided. ADI-R, Autism Diagnostic Interview-Revised; ADOS, Autism Diagnostic Observation Schedule.

Figure 2.

Distribution of parent-reported sleep duration. Plotted is the distribution of sleep durations that were reported in the Simons Simplex Collection medical histories for children with ASD (n = 2,714). The mean reported sleep duration was 555 +/−76 minutes. The frequency of sleep duration in the lower 5th (≤420 minutes) and upper 95th (≥660 minutes) percentile of the distribution are indicated with brackets.