Objectives: To examine the relationships between sleep problems and phenotypic characteristics of preschool children with ASD (i.e., cognitive, language and adaptive skill level, ASD and comorbid emotional-behavioral symptoms), as well as parental stress.
Methods: Data were drawn from the Pathways in ASD study and included 363 preschoolers from five Canadian provinces, who were assessed within 4 months of diagnosis (mean age = 40.8 months, range 24-64 months). Parent-reported sleep concerns were assessed using the Children’s Sleep Habits Questionnaire (CSHQ) total score. Other child characteristics were assessed using the Autism Diagnostic Observation Schedule (ADOS), the Merrill-Palmer-Revised Scales of Development (M-P-R), the Preschool Language Scale – 4 (PLS-4), the Vineland Adaptive Behavioral Scales-II (VABS-II) and the Child Behavior Checklist 1.5-5 (CBCL). Parents also completed the Parenting Stress Index-Short Form (PSI-SF). We examined whether age, sex and clinical features correlated with sleep concerns using Pearson r, followed by simple linear regression to examine the independent contributions of features showing positive correlations. We also examined the correlation between severity of sleep concerns and level of parental stress.
Results: Mean CSHQ total scores (44.9+8.4) were comparable to those reported in other preschool ASD cohorts (Goldman et al., 2012), with 224 of 363 (59.0%) scoring above the cut-point suggestive of clinically significant sleep problems (Owens et al., 2000). CSHQ total scores were not associated with sex (t361=.02, p=.99), age (r=.01, p=.80), cognitive level indexed by the M-P-R (r=-.07, p=.20), nor language level on the PLS-4 (r=-.06, p=.28), but were positively correlated with internalizing and externalizing symptoms on the CBCL (r=.42, p<.001 and r=.43, p<.001, respectively) and negatively correlated with ASD symptom severity on the ADOS (r=-.11, p=.03) and adaptive skills on the VABS-II (r=-.11, p=.04). The linear regression model that included the CBCL, ADOS and VABS-II accounted for 22% of the variance in CSHQ scores, with only the CBCL contributing unique variance (internalizing symptoms, ß=.24, p=<.001 and externalizing symptoms, ß=.25, p=<.001). CSHQ scores were also correlated with parental stress on the PSI-SF (r=.33, p<.001).
Conclusions: Parent-reported sleep problems were common across this large cohort of preschool children with ASD. Severity of sleep problems was significantly correlated with internalizing and externalizing symptoms (but not independently with ASD symptom severity nor cognitive/language levels) as well as parental stress. While the directionality of these relationships cannot be determined with cross-sectional data, recognizing that sleep problems, emotional-behavioral dysregulation and parental stress often co-occur may have important implications for both clinical surveillance and appropriate multi-faceted management. Future research with this longitudinal cohort will examine the reciprocal relationships between sleep problems, emotional-behavioral symptoms and parental stress over time, as well as the impact of interventions.
See more of: Medical Co-Morbid Conditions
See more of: Symptoms, Diagnosis & Phenotype