Understanding the dynamic association between sleep quality and mood in children and adolescents with cerebral palsy

BACKGROUND: Cerebral palsy (CP) is one of the most prevalent long-term childhood conditions. Children and adolescents with CP are at elevated risk for mental health difficulties, which contribute to reduced quality of life and daily functioning. Sleep difficulties are a well-established risk factor for mental health. Poor sleep quality has been linked to worse mood in youth with and without neurodevelopmental disabilities. However, most studies in youth with CP have focused on average sleep metrics over time, rather than examining intraindividual variability (IIV) using daily assessments, which may reduce retrospective reporting biases. This study examined the dynamic and bidirectional association between sleep quality, sleep duration, and mood in youth with CP. METHODS: Thirty-two youth with CP (aged 11-17 years; 45.5 % girls) were recruited from health and community agencies. Youth completed daily diaries over seven consecutive days. Each day, youth rated their sleep quality, sleep duration, and levels of daily mood (operationalized as positive and negative affect using the Positive and Negative Affect Scale PANAS). Multilevel models examined bidirectional associations between sleep quality, sleep duration, and mood, controlling for gender, age, and GMFCS level. RESULTS: At the between-person level, higher previous-day sleep quality was significantly associated with greater next-day positive mood and lower negative mood, and higher negative mood was associated with poorer sleep quality the following night. At the within-person level, increases in sleep quality were associated with higher next-day positive mood only. Sleep duration was not significantly associated with next-day mood at either level. CONCLUSION: Findings highlight both between-person and within-person associations between sleep quality and mood in youth with CP, with bidirectional associations observed at the between-person level and unidirectional associations at the within-person level.