Autism Spectrum Disorders Introduction Autism Spectrum Disorders (asd) Are Neurode- Velopmental Disorders Characterized by Defi- Cits in Social Interaction and Communication,

AUTISM SPECTRUM DISORDERS (ASD) ARE NEURODEVELOPMENTAL DISORDERS CHARACTERIZED BY DEFICITS IN SOCIAL INTERACTION AND COMMUNICATION, with restricted interests and repetitive behaviors.1 Parentally reported sleep concerns are common in ASD, with prevalence rates of 44%-83%.2 Even in children with average intelligence, sleep problems in ASD have been reported to be more prevalent and severe than in to ageand sex-matched typically developing (TD) children.3 Insomnia, defined as difficulty initiating or maintaining sleep, has been documented consistently in children with ASD in studies using parentally completed questionnaires, sleep diaries, or both.2,4-7 Parental reports of daytime sleepiness, sleep disordered breathing, and parasomnias (e.g., head banging, sleep terrors) have also been reported, but with lesser frequency than insomnia, in comprehensive investigations of large numbers of children with ASD.6 While parental sleep concerns have been well documented in children with ASD, few studies have related these concerns to polysomnographic (PSG) findings. Documenting PSG abnormalities in children with ASD whose parents report sleep concerns provides objective evidence of disordered sleep in these children (i.e., sleep concerns do not simply reflect parental over reporting in this group of highly stressed caregivers). Furthermore, few investigators have examined the relation of both parental report and physiological sleep variables to measures of daytime behavior and autism symptomatology. The goals of our study were (1) To determine whether parental reports of sleep concerns correspond to physiological measures of sleep, and (2) To examine the relation of parental and physiological measures of sleep to daytime behaviors and autism symptomatology. To accomplish these goals, we characterized sleep in children with ASD using multiple measures, including parental report, a validated sleep questionnaire, sleep histories, sleep diaries, and two nights of video-EEG-PSG. Validated measures of daytime behavior and autism symptomatology were also collected. To minimize effects of confounding factors, we limited our cohort to children with ASD 4-10 years of age who were medication-free and seizure-free and did not have mental retardation. Typically developing children 4-10 years of age were included as a comparison group.