Abstract
Sleep difficulties are common in children with rare genetic syndromes and are associated with clinical features such as behaviours that challenge and mental health difficulties. This study aimed to further clarify the role of sleep difficulties in children's clinical outcomes by (1) describing profiles of sleep difficulties in syndromes that had received little or no detailed sleep investigation, such as KBG and Kleefstra syndrome; (2) statistically controlling the interactions between clinical features when examining the associations with sleep difficulties; and (3) exploring the associations between sleep difficulties and demographic characteristics. Overall, this study aimed to describe the profiles of sleep difficulties experienced within genetic syndromes and examine the associations between sleep difficulties, clinical features, and demographic characteristics.
Caregivers of children with rare genetic syndromes (N = 251, aged 1-18 years) completed questionnaires that assessed sleep difficulties and various clinical features. Profiles of sleep difficulties were described by syndrome and compared via odds ratios to typically-developing children. Structural equation modelling was used to examine the associations between sleep difficulties, clinical features, and demographic characteristics, whilst controlling for interactions between clinical features.
Across most syndromes, night wakings, bedtime resistance, sleep-disordered breathing, parasomnias, and sleep duration difficulties were elevated compared to typically-developing children, although several syndrome-specific profiles of sleep difficulties were also observed. Across syndromes, sleep difficulties were significantly, positively associated with anxiety and depressed mood, autism-related characteristics, overactivity and impulsivity, epilepsy severity, and the severity of physical health conditions. Of the demographic characteristics, sleep difficulties were associated with socioeconomic status.
These findings have several implications. Firstly, the profiles of sleep difficulties described in syndromes with little prior sleep investigation (e.g. Coffin-Siris, KBG, and Kleefstra syndrome) highlights the need to investigate sleep in more detail in these groups and further informs the phenotypes of the syndromes. Secondly, sleep difficulties were associated with numerous clinical features, even after controlling for other predictors, highlighting the importance of sleep as a clinically modifiable variable that could improve clinical outcomes in rare syndromes. Thirdly, the association between sleep difficulties and socioeconomic status highlights the need to examine environmental determinants of poor sleep in children with rare genetic syndromes.