Objectives: To describe actigraphically detected and parent-reported sleep problems in nonmedicated children with attention-deficit/hyperactivity disorder (ADHD); to clarify whether or not comorbid oppositional defiant disorder contributes to sleep difficulties; and to compare objectively measured sleep with the parents' observations of sleep.
Design: Case-control study.
Setting: A child and adolescent psychiatric department of a teaching hospital.
Participants: Two hundred six children aged 5 to 11 years, including 45 with a diagnosis of ADHD, 64 with a diagnosis of other psychiatric diagnoses (psychiatric control group), and 97 healthy control subjects (reference group). Intervention Sleep was monitored by parent-completed sleep diaries and 5 nights of actigraphy. We used a semistructured interview to diagnose psychiatric disorders according to Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) criteria.
Main outcome measures: Actigraphically measured sleep variables and parent-estimated sleep by diary.
Results: We found that children with ADHD have significantly longer sleep onset latency and a more irregular sleep pattern than the psychiatric control or healthy reference subjects. Average sleep onset latencies were 26.3 minutes in the ADHD group, 18.6 minutes in the psychiatric control group, and 13.5 minutes in the healthy reference group. There was no apparent relationship between sleep problems and comorbid oppositional defiant disorder. We found discrepancies between the objectively measured sleep variables and those reported by parents, who overestimated sleep onset latency.
Conclusions: The results of this study allow us to conclude that some children with ADHD have impaired sleep that cannot be referred to comorbid oppositional defiant disorder. However, it is important to make an in-depth review of the sleep complaints, as the problem may be a product of the parents' perception rather than the child's actual experience.
Trial registration: ClinicalTrials.gov NCT00224731.