1132 Sleep Inertia is a Key Marker in Adult ADHD

Abstract Introduction Attention-deficit/hyperactivity disorder (ADHD) is increasingly understood as a disorder involving not only executive dysfunction but also disturbances in arousal regulation. Daytime sleepiness, sleep inertia, and impaired alertness may contribute to attentional instability and chronic functional impairment, yet population-based longitudinal data on these associations remain scarce. This study focuses on examining the role of daytime sleepiness and sleep-wake regulation factors associated to the presence and persistence of ADHD. Methods A representative sample of non-institutionalized U.S. adults aged ≥18 years was interviewed in two waves between 2002 and 2015 using the Sleep-EVAL system, an AI-driven diagnostic platform. Wave 1 (W1) included 15,929 participants, of whom 10,931 were interviewed again approximately three years later (W2). ADHD diagnoses were based on DSM-5 criteria. Logistic regression models were performed to identify predictors associated with ADHD and its persistence (present at both interviews). The models emphasized sleep-wake symptoms including sleep inertia, subjective sleepiness across contexts, insomnia, non-restorative sleep, and fatigue. Results At W1, 5.7% of adults met criteria for ADHD, decreasing to 4.5% at W2; nearly half (47.4%) of cases remained persistent over three years. ADHD was more frequent in men and declined significantly after age 55. Sleep-wake disturbances were among the strongest predictors of ADHD at W1. Sleep inertia showed the largest association (OR=4.63), followed by severe fatigue (OR=2.07) and sleepiness in situations requiring high attention (OR=1.45). Insomnia and non-restorative sleep were not independently associated with ADHD when arousal-related variables were included. For ADHD persistence, the presence of sleep inertia at W1 was a strong predictor (OR=5.68), along with severe fatigue (OR=4.86) and insomnia (OR=1.43). Comorbid depressive (OR=2.62) and anxiety disorders (OR=1.34) at W1 also predicted ADHD persistence. Conclusion ADHD in adults is strongly associated with symptoms of impaired arousal regulation, particularly morning sleep inertia, context-dependent daytime sleepiness, and severe fatigue. These disturbances are not only cross-sectional correlates but also major determinants of ADHD persistence over time. Support (if any)