Abstract
BACKGROUND: People with attention deficit hyperactivity disorder (ADHD) often report disturbed sleep, as well as co-occurring symptoms of anxiety and depression. Yet studies employing objective assessments often do not show as many sleep disturbances compared to subjective measures. These discrepancies may relate to subjective reports capturing problematic nights, which may not be captured in a single night's sleep or by averaging objective measurements over several nights. Given that variability in behaviours is in general strongly linked to ADHD, individuals with ADHD could have greater sleep variability than individuals without ADHD. Using active and passive remote monitoring, we investigate differences in the level and variability of daily sleep behaviours between individuals with and without ADHD and explore if sleep is associated with changes in anxiety and depressive symptoms across a 10-week remote monitoring period. METHODS: Forty individuals (20 with ADHD, 20 without) took part in a 10-week remote monitoring study. Active monitoring involved participants completing questionnaires on ADHD and co-occurring psychiatric symptoms at weeks 2, 6 and 10. Passive monitoring involved participants wearing a wearable device (Fitbit) that measured sleep each night. RESULTS: Individuals with and without ADHD were similar in the levels of sleep recorded each night. However, compared to those without ADHD, participants with ADHD had more variable sleep duration, sleep onset and offset, and sleep efficiency over 10 weeks. Within-individual associations of co-occurring anxiety and depressive symptoms with the sleep features were non-significant. CONCLUSIONS: In a 10-week remote monitoring study of sleep using a wearable device, we show that what distinguishes individuals with ADHD from those without is their greater variability in sleep features: participants with ADHD had a more variable sleep duration, sleep onset and offset, and sleep efficiency. Inconsistency and high variability are hallmarks of ADHD, and we show that this characteristic extends also to sleep among adolescents and adults with ADHD. TRIAL REGISTRATION: Clinical trial number: not applicable.