Sleep disorders in adults with Cri du Chat syndrome: A questionnaire-based study

Background Sleep disorders are increasingly recognized in individuals with Cri-du-Chat (CdC) syndrome, yet most available data focus on pediatric populations. The present study investigated the prevalence, characteristics, and potential determinants of sleep disturbances in adults with CdC syndrome using standardized and validated scales and questionnaires. Findings were also compared with previously published pediatric data to explore developmental trajectories and persistence of sleep problems into adulthood. Methods Adults (≥18 years) with genetically confirmed CdC syndrome were recruited through the Italian Associazione Bambini Cri du Chat ONLUS (A.B.C.). Between September and October 2025, caregivers completed a structured questionnaire comprising general demographic and clinical data, and four standardized sleep assessment instruments: the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Epworth Sleepiness Scale (ESS), and the Sleep Questionnaire for Children with Severe Psychomotor Impairment (SNAKE). Results Seventy adults (median age 31 years) were included. Poor sleep quality and insomnia symptoms were detected by using PSQI and ISI in 49% and 35.7% of participants, respectively. According to SNAKE results, disturbances in sleep maintenance were the most frequent (47.1%), followed by sleep-onset difficulties (25.7%) and daytime sleepiness (22.9%). A large proportion of participants with SNAKE scores suggestive of a clinically relevant sleep problem had never undergone a formal diagnostic evaluation for a sleep problem, highlighting a potential gap in clinical recognition. After adjustment for age, sex, and degree of intellectual disability, older age was independently associated with poorer overall sleep quality, greater insomnia severity, and increased daytime sleepiness, while epilepsy was independently associated with greater daytime sleepiness, and severe intellectual disability was associated with more pronounced daytime behavioural disturbances. Conclusions Sleep problems are common yet underdiagnosed in adults with CdC syndrome, often persisting from childhood into adulthood. These findings emphasize the need for systematic sleep screening and multidisciplinary management in this population, integrating behavioural, neurological, and environmental factors.