(PS1-78) Subjective Sleep Problems across the Menstrual Cycle in Females with ADHD

Abstract Text: Sleep difficulties are common among individuals with ADHD, who frequently report disturbances in sleep, daytime sleepiness, and circadian rhythm abnormalities. Yet, sleep, like eating, ADHD, and mood show clinically significant variation across the menstrual cycle in women. Yet, little is known about nightly subjective sleep variation across the menstrual cycle in females with ADHD. Longitudinal evidence shows that sleep problems are most common during the perimenstrual phase, or just before menstruation. This study examines how sleep—specifically hypersomnia and insomnia—varies across the menstrual cycle in females with rigorously confirmed, clinically significant ADHD symptoms.
Seventy-eight individuals (assigned female at birth) with regular menstrual cycles, overrecruited for ADHD, provided daily saliva samples, completed an ADHD symptom checklist, and rated their sleep (hypersomnia, insomnia) each evening for up to two menstrual cycles. Luteinizing hormone surge was verified via urine ovulation tests. Individual luteal and follicular phase lengths were estimated using menses and ovulation dates, and the percent of the phase elapsed (cycle time) was used as a predictor in generalized additive mixed models (GAMMs) examining zero-order associations between cycle time and sleep outcomes.
Results revealed significant within-person variability in sleep ratings, with intraclass correlations (ICCs) ranging from 0.29 for hypersomnia to 0.38 for insomnia, indicating that roughly two-thirds of the variance in these outcomes is within-person, or due to changes within person based on cycle time. Moreover, GAMM analyses showed that cycle time significantly predicted nonlinear trends in insomnia (edf = 4.98, F = 2.08, p = 0.006, R² = 0.34), reflecting dynamic changes in insomnia across the menstrual cycle, specifically at the start of menstruation. In contrast, the effect of cycle time on hypersomnia (edf = 3.97, F = 1.68, p = 0.115, R² = 0.26) was not statistically significant, suggesting that hypersomnia levels remain relatively stable across cycle phases. Significant random intercepts confirmed robust between-person differences in overall sleep quality, while nonsignificant random slopes indicated a consistent cycle effect between individuals.
In conclusion, menstrual cycle time has significant nonlinear effects on insomnia symptoms in females with ADHD such that insomnia is worst at end and beginning of the cycle with menstruation whereas there is not quite evidence that that is true for hypersomnia. The relatively modest variance explained by cycle time suggests that other factors—such as stable individual traits, external influences, or environmental stressors—may play a larger role in shaping sleep disturbances. Future research should explore how trait and external factors moderate cyclical changes and hormonal impacts on sleep outcomes among individuals with ADHD who are sensitive to menstrual cycle fluctuations.