Effect of lisdexamfetamine dimesylate on sleep in adults with attention-deficit/hyperactivity disorder

Background: Sleep problems are common in adults with attention-deficit/hyperactivity disorder (ADHD). This analysis aimed to evaluate the impact of lisdexamfetamine dimesylate (LDX) on sleep quality in adults with ADHD. Methods: This 4-week, phase 3, double-blind, forced-dose escalation study of adults aged 18 to 55 years with ADHD randomized participants to receive placebo (n = 62), or 30 (n = 119), 50 (n = 117), or 70 (n = 122) mg/d LDX, taken once a day in the morning. The self-rated Pittsburgh Sleep Quality Index (PSQI) was administered at baseline and at week 4 to assess sleep quality. The PSQI global score assesses 7 sleep components (subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleeping medications, and daytime dysfunction) each scored from 0 (no difficulty) to 3 (severe difficulty). Results: The mean baseline PSQI global score was 5.8 for LDX and 6.3 for placebo (P = .19) indicating poor overall sleep quality. At endpoint, least squares (LS) mean change from baseline was -0.8 for LDX vs -0.5 for placebo (P = .33). The daytime functioning component showed significant improvement in LS mean change at endpoint for LDX compared with placebo (LDX -0.4 vs placebo 0.0, P = .0001). LS mean changes for the other 6 PSQI components did not significantly differ from placebo. Sleep-related treatment-emergent adverse events with an incidence >= 2% in the active treatment and placebo groups, respectively, were insomnia (19.3% and 4.8%), initial insomnia (5.0% and 3.2%), middle insomnia (3.6% and 0%), sleep disorder (0.6% and 3.2%), somnolence (0.3% and 3.2%), and fatigue (4.7% and 4.8%), and were generally mild or moderate in severity. Conclusion: For most subjects, LDX was not associated with an overall worsening of sleep quality and significantly improved daytime functioning in adults with ADHD.