Sleep patterns and daytime sleepiness in adolescents and young adults with Williams syndrome

Background Sleep disorders are common in individuals with neurodevelopmental disorders and may adversely affect daytime functioning. Children with Williams syndrome have been reported to have disturbed sleep; however, no studies have been performed to determine if these problems continue into adolescence and adulthood. Methods This study examined overnight sleep patterns and daytime sleepiness in 23 adolescents and adults with Williams syndrome age 25.5 (8.0) years [mean (SD)]. Interviewer‐administered sleep questionnaires were used to evaluate nighttime sleep behaviours and daytime sleepiness. Wrist actigraphy was used to evaluate sleep patterns. Results Although individuals in our sample averaged 9 h in bed at night, daytime sleepiness and measures of sleep disruption were common and comparable to those of other populations with neurodevelopmental disorders. These measures included reduced sleep efficiency [74.4 (7.0)%] with prolonged sleep latency [37.7 (37.3) min], increased wake time after sleep onset [56.1 (17.6) min], and an elevated movement and fragmentation index [14.3 (4.6)]. Conclusion Adolescents and young adults with Williams syndrome were found to be sleepy despite averaging 9 h in bed at night. Implications are discussed for associated causes of sleep disruption and future polysomnographic evaluation.