The impact of psychostimulants on sleep in ADHD adults: a randomized cross-over trial

Purpose Attention-Deficit/Hyperactivity Disorder (ADHD) is a highly prevalent neurodevelopmental disorder affecting both pediatric and adult populations. Stimulant medications (STM) including methylphenidate (MPH) or lisdexamfetamine (LDX) are recommended as first-line treatment for ADHD symptoms, although evidence regarding their impact on sleep in adults remains unclear. Methods 36 adults with ADHD, previously identified as good responders to STM, underwent clinical screening and an adaptation night with polysomnography (PSG). Subsequently, 15 participants were included and randomized in a cross-over trial. These participants completed two PSG nights at the sleep center after they spent either a week under STM or without medication (randomized order of conditions). Subjective measures were collected through questionnaires and sleep diaries, while objective sleep parameters were assessed using both actigraphy and PSG. Results STM (compared to no medication) reduced self-reported fatigue and improved subjective sleep quality, with parallel effects on objective measures showing fewer transitions from deeper to lighter sleep stages, and fewer arousals during deep sleep. STM also increased the peak frequencies of both fast sleep spindles, which was associated with increased dream experience, and slow oscillations. Conclusio These findings suggest a beneficial and stabilizing effect of STM onthe sleep-wake cycle in adults with ADHD leading to better sleep. Whether this main result relates to a general mechanism of improved sleep-wake homeostasis (elevated daytime attention and consolidated sleep), driving a virtuous therapeutic cycle, would require further research. The present findings thus show that STM may be administered to adult ADHD patients without causing adverse sleep outcomes. Clinical trial number Not applicable