1092 Attention-deficit/hyperactivity Disorder Symptoms And Sleep Characteristics Within A Seasonal Affective Disorder Spectrum

Abstract

Introduction: Seasonal affective disorder (SAD) increases risk for attention-deficit/hyperactivity disorder (ADHD), although the mechanism linking SAD and ADHD is unknown. Prior research has identified insomnia and delayed sleep phase in both ADHD and SAD. We hypothesized that sleep duration and timing in SAD would be associated with the severity of ADHD symptoms. Methods: Adults with SAD (n = 45) and subsyndromal SAD (S-SAD; n = 18) aged 19-66 years from Pittsburgh, PA., were assessed for ADHD symptoms, self-report sleep quality, depression severity, and daytime sleepiness in the Winter. Participants wore an Actiwatch for 4-14 days, from which we calculated sleep-onset latency, total sleep time, sleep midpoint, and sleep efficiency. We conducted a hierarchical multivariate linear regression to determine if sleep characteristics predict ADHD symptom severity in our sample while controlling for depressive symptoms. Age and gender were added in Step 1, seasonal depression severity in Step 2, actigraphy-based total sleep time, sleep onset latency, midpoint, and efficiency in Step 3, and self-reported sleep quality and daytime sleepiness in Step 4. Results: Participants mostly scored in the likely or highly likely ADHD range (87.30%, n=55), higher than the national prevalence rate (4.4%). When controlling for age, gender, and depression severity, only shorter actigraphy-based total sleep time was associated with higher ADHD symptom severity (β=-0.30, p<0.05). However, when self-reported sleep quality and daytime sleepiness were added as predictors, total sleep time was no longer a statistically-significant predictor of ADHD symptom severity and only daytime sleepiness predicted ADHD symptom severity (β=0.31, p<0.05). Conclusion: Our results suggest that individuals with SAD who experience daytime sleepiness and/or possibly shorter actigraphybased sleep duration experience higher ADHD symptom severity. Treatments like Trans-C or CBT-I to improve daytime sleepiness and sleep duration may be indicated for SAD patients who present with comorbid ADHD symptoms.