Sleep in children with attention-deficit/hyperactivity disorder:: A restatement on sleep studies.

Since 1970, a certain number of studies have reported sleep disturbances in children with AND. Data from questionnaires and parental reports showed behavioural difficulties occurring at wake-sleep transition such as bed-time refusal, delayed sleep-onset, early awakenings, suggesting the occurrence of specific abnormalities in the mechanisms of alertness maintainance. Few polysomnographic studies have been conducted in ADHD children considering the prevalence and the importance of the disorder in the field of child psychopathology, The majority of these studies produced heterogenous and conflicting data and no clear abnormalities of non-rapid eye movement or REM sleep were found. Polysomnographic data, however supports the evidence of sleep-wake-transition abnormalities in ADHD children. Modifications in sleep-onset-latencies, number of stage shifts, have previously been reported using all-night polysomnography. One study performed Multiple latency tests in ADHD children and concluded that ADHD had daytime sleep abnormalities when compared with controls. One other important issue concerns motor activity during sleep in hyperactive children which was found to be increased in studies using actigraphy or video analysis, These findings could lead to important clinical and therapeutic applications as stimulants could help to normalise sleep or motor behaviour during sleep in some ADHD children. (C) 2002 Editions scientifiques et medicales Elsevier SAS.