Characterisation of sleep problems in children with Williams syndrome.

Sleep is critical to optimal daytime functioning, learning and general health. In children with established developmental disorders sleep difficulties may compound existing learning difficulties. The purpose of the present study was to evaluate the prevalence and syndrome specificity of sleep problems in Williams syndrome (WS), a neurodevelopmental disorder affecting around 1 in 20,000 live births. Parents of 64 children with WS, aged 6-12 years, and 92 age matched healthy controls were surveyed about their child's sleep habits. The Child Sleep Habits Questionnaire, general health and background information were collected from the parents. Ninety seven percent of parents reported that their children had sleep problems and reported a high prevalence of sleep difficulties: greater bedtime resistance, sleep anxiety, night waking and daytime sleepiness. This is the first study to our knowledge to survey sleep problems in a large cohort of school age children with WS. Sleep problems in children with learning difficulties are often amendable to treatment if diagnosed early. Furthermore the negative impact of sleep disturbances on daytime behaviour and learning should be measured before diagnoses of behaviourally defined disorders are considered.