Parent and Child Factors Associated with Sleep Problems in Pervasive Developmental Disorders, Down Syndrome and Intellectual Disability

Background:

Parent-reported sleep problems are common in children with a developmental disability, particularly those with a pervasive developmental disorder (PDD).  Child sleep difficulties have been associated with challenging behaviour, child psychopathology and parent stress, but whether or not the relationship of these factors with child sleep differs across developmental disorders is largely unexplored.

Objectives:

The aim was to examine whether parent or child factors purported to be associated with problematic child sleep differed for children with PDD, Down syndrome (DS) or intellectual disability (ID).

Methods:

This was part of a larger study examining the influence of parent and child characteristics on sleep in children with a developmental disability. Parents (N = 76) completed demographics, Behavioral Evaluation of Disorders of Sleep (BEDS), Developmental Behavioural Checklist (DBC), Adaptive Behavior Assessment System, Eysenck Personality Questionnaire-R, Parenting Sense of Competence, Parenting Hassles Scale, Levenson’s Locus of Control Scale, and rated perceived control over their child’s sleep and behaviour.  Using BEDS scores children (M = 10.6 years, SD = 4.4) were classified into 3 groups: Recognised Sleep Problem (RSP), Unrecognised Sleep Problem (USP), and No Sleep Problem (NSP). Within the 76 families, three main developmental groups (N = 62) were also identified PDD (n = 30), ID (n = 18) or DS (n = 14). A series of Kruskal-Wallis tests and multiple comparisons using Mann-Whitney tests (Bonferroni adjusted alpha = .017) were used to examine differences between the 3 sleep groups within each developmental group for these parent and child measures. 

Results:

For the PDD group the sleep groups differed significantly on the DBC total score, the DBC self-absorbed, depression and hyperactivity subscales and the DBC autism screen.  Hyperactivity differed for the RSP and USP, and RSP and NSP groups whereas for the other DBC scores only the RSP and NSP groups differed. For the DS group the sleep groups differed on parents’ perceived control over their child’s sleep behaviour with the RSP and NSP groups differing. No other child measures and no parent measures differed for the PDD or DS groups. No significant sleep group differences were found for any measure for the ID group.

Conclusions:

Factors associated with sleep problems differed for children with a PDD, DS or ID. Sleep problems were related to behaviour for children with a PDD, particularly hyperactivity, but this was not so for DS or ID.  Thus behavioural issues play a significant part in sleep difficulties in children with a PDD compared with other disabilities.  This underscores that examining sleep and behaviour in mixed disability groups may obscure findings. It reinforces that when examining relationships between child sleep and parent or child behaviour, developmental disorders should be investigated separately.  Further research with larger sample sizes is needed to confirm our results.

Author Note: Both authors were formerly at RMIT University. These data are from Dr. Robinson's dissertation, conducted there with Dr.Richdale as senior supervisor.