A Good Night Sleep: An Examination of the Relationship Between Sleep and Neuropsychological Profiles In School-Aged Children with Autism Spectrum Disorders

Background: Children with autism spectrum disorders (ASD) exhibit increased sleep disturbances as compared to their typically developing peers. Literature suggests that disturbances in sleep are likely multifactorial and associated with developmental, genetic, environmental, and/or neuroanatomic and physiologic dysfunction.  Previous ASD studies have primarily focused on associations between sleep disturbance and daytime behaviors. However, research examining the relationship between sleep profiles in high-functioning children with ASD and everyday neuropsychological functioning is currently limited.

Objectives: The present study seeks to expand on research of sleep profiles in ASD by investigating the relationship between sleep behaviors and executive, adaptive and emotional functioning in everyday settings in an exclusively high-functioning, pre-adolescent sample with ASD.  We predicted that sleep disturbance would be more severe in the ASD group, and that they would relate to problems with the aforementioned areas of functioning.

Methods: 73 school-aged children (TD, N=20, FSIQ=117; ASD, N=53, FSIQ=107), matched on age (6.73-12.98yrs), sex-ratio and SES, were recruited for research studies conducted at Children’s National Medical Center. Children in the ASD group were diagnosed using DSM-IV criteria, ADI and ADOS and had no significant medical history of mood disorders and seizures.  Participants completed an extensive diagnostic battery and parents reported on sleep behavior, executive, adaptive and emotional functioning. Administered parent reports included: Children’s Sleep Habits Questionnaire (CSHQ; comprehensive sleep behavior questionnaire); Behavior Rating Inventory of Executive Function (BRIEF; measure of everyday executive function [EF]); Child Behavior Checklist (CBCL; scale of childhood behaviors and emotions); Vineland Adaptive Behavior Scales -1^st and 2^nd Editions (VABS; comprehensive measure of adaptive functioning skills); and DSM-IV ADHD Parent Rating Scale.

Results: Analyses revealed significant group differences on CSHQ dimensions of Sleep Anxiety (TD=4.38;ASD=5.37), Excessive Daytime Sleepiness (EDS) (TD=8.66;ASD=12.64) and Total Sleep Disturbances (TD=28.73;ASD=35.63). Relative to the TD group, the ASD group reportedly had more sleep disturbance within these domains (p-values range from .001-.025). Correlation analyses within the ASD group revealed significant positive relationships between increased sleep anxiety and behavioral symptoms including Anxiety and Depression (r(53)=.52, p=.001), Somatic Complaints (r(53)=.34, p=.01) and Attention Problems (r(53)=.36, p=.01). EDS was correlated with behavioral symptoms including Withdrawn and Depressed (r(53)=.40, p=.003), Somatic Complaints (r(53)=.31, p=.03), and Attention Problems (r(53)=.38, p=.01); increased ADHD Inattention Symptoms (r(52)=.33, p=.02); Metacognitive EF deficits (r(53)=.45, p=.001); and impaired Socialization Skills (r(52)=-.35, p=.01).

Conclusions: Preliminary results from this ongoing study outline a possible sleep profile characterized by increased sleep anxiety, EDS and overall greater sleep disturbances in high-functioning children with ASD as compared to TD peers. Our findings within ASD, suggest a positive association between sleep disturbance and behavioral symptoms (e.g., anxiety, depression, inattention & somatic complaints) associated with common co-morbid disorders. Furthermore, EDS was related to deficits in executive functioning (e.g. working memory, planning & organization) and adaptive behavior (e.g., socialization skills). These findings indicate a need to further examine sleep profiles as a factor in the clinical presentation of core adaptive and executive impairments in ASD. Additionally, results provide support for sleep intervention and its potential impact on neuropsychological functioning in children with ASD.