Abstract
OBJECTIVE: To examine how changes in sleep patterns and sleep problems occurring between the pre-pandemic and the Covid-19 lockdown period influenced mood-behavioral functioning of children with Attention Deficit Hyperactivity Disorder (ADHD). METHODS: Parents of 992 children with ADHD (85.4% boys, mean age: 11.52 years, SD = 3.17), recruited from the Italian ADHD family association, completed a modified version of the Sleep Disturbance Scale for Children and filled out 11 emotional behavioral items selected from the Child Behavior Checklist (CBCL) 6-18 questionnaire. Subgroups identified based on sleep duration changes ("maintained", "increased", "reduced") and of sleep problems during lockdown ("onset", "remission", "maintained", "no sleep problem") were analyzed to evaluate the association with internalizing and externalizing scores. RESULTS: Sleep duration showed no or low influence on internalizing and externalizing behaviors after control for age, sex, and socioeconomic status. Patients with ADHD with "no sleep problem" showed significant lower scores in internalizing and externalizing behaviors than those who "maintained" or had "onset" of different sleep problems. The effect sizes were higher for internalizing than externalizing behaviors. Lower internalizing scores were found in those who remitted difficulty in falling asleep, daytime sleepiness, nightmares, vs. the "maintained" or "onset" groups and those who remitted hypnic jerks vs. the "onset" group. Children with ADHD who "maintained" sleep terrors reported higher internalizing and mainly externalizing scores than the other groups. CONCLUSION: Sleep problems negatively influence daytime functioning of patients with ADHD. but mood and behavioral domains show different susceptibility to the changes of sleep problems, and different vulnerability to specific sleep problems.