Sleep, academic achievement, and cognitive performance in children with attention-deficit hyperactivity disorder: A polysomnographic study.

The objective of this study was to examine the influence of parent-reported and polysomnography (PSG)-measured sleep patterns on the academic and cognitive performance of children with attention-deficit hyperactivity disorder (ADHD). We assessed 91 children (18 girls) diagnosed with ADHD aged 7-11 years (29 ADHD-Inattentive, 32 ADHD-Hyperactive/Impulsive, and 31 ADHD-Combined). The Paediatric Sleep Questionnaire (PSQ) and Paediatric Daytime Sleepiness Scale (PDSS) were used to assess subjective sleep quality, as perceived by parents, and objective sleep variables were assessed by PSG. Cognitive performance was evaluated using the Wechsler Intelligence Scale for Children (WISC), and the final average grade of the last school year was used as a measure of academic performance. Academic performance was predicted by the following sleep variables: Sleep time, time in bed, night awakenings, and daytime sleepiness. The best predictors of cognitive performance in children with ADHD were rapid eye movement latency, light sleep, periodic limb movements index (PLMs), awakenings, and daytime sleepiness. In conclusion, sleep parameters are closely associated with the academic and cognitive functioning of children with ADHD.