An exploratory study of sleep quality and quantity in children with causal variants in SYNGAP1, an autism risk gene

Sleep disturbances are reported in 62% of children with SYNGAP1-Intellectual Disability (SYNGAP1-ID), a rare neurodevelopmental disorder characterized by intellectual disability, epilepsy, autism spectrum disorder (ASD), sensory and behavioral challenges. Although Children's Sleep Habits Questionnaire (CSHQ) scores are elevated in children with SYNGAP1-ID factors that predict sleep disturbance are not well understood. The goal of this study is to identify predictors of sleep problems.

Parents of 21 children with SYNGAP1-ID completed questionnaires, and 6 children wore the Actiwatch2 for 14 continuous days. Non-parametric analysis of psychometric scales and actigraphy data were performed. Actigraphy derived sleep parameters were compared to controls and rest activity rhythms were assessed using arctools an open-source R package.

CSHQ total sleep scores in children with SYNGAP1-ID and ASD were not different from children with SYNGAP1 without ASD (p = 0.61). Sleep anxiety (β 1.646, 95% CI 0.9566 to 2.336) and parasomnias (β 0.6294, 95% CI 0.06423 to 1.195) were strong predictors of bedtime resistance (R² = 0.767, p < 0.001). The sedentary to active transition probability during the 12-18 h epoch (β = 0.004, p = 0.008, R² = 0.85) and the duration of the active bout during the 18-24 h epoch (β = 0.166, p = 0.029, R² = 0.74) were strong predictors of total sleep disturbance.

The CSHQ may be a reliable measure of sleep difficulties in children with SYNGAP1-ID. Sleep anxiety, parasomnias and difficulty winding-down are significant contributors to sleep disturbances.