0372 Quetiapine Effect on Sleep, Breathing, and Next Day Performance in People with OSA and Difficulty Maintaining Sleep

Abstract Introduction Quetiapine is commonly prescribed "off-label" to people with insomnia symptoms. People with undiagnosed obstructive sleep apnea (OSA) frequently report insomnia symptoms, particularly difficulties in maintaining sleep. In 2020, 10.6 million prescriptions were dispensed for quetiapine in the United States. Yet, there is limited information regarding the effects of quetiapine on breathing, sleep, and next-day performance in people with OSA. Methods We performed a double-blind, randomized, placebo-controlled, cross-over study (NCT05303935) in 15 people with OSA who also reported difficulty maintaining sleep. Participants were studied overnight via polysomnography on two separate occasions ~1 week apart and received either 50mg of quetiapine or a placebo (order randomised) just prior to sleep. 10-minute psychomotor vigilance and 30-minute AusEd driving simulator tests were performed each morning. Results Participant demographics: 7 women, 8 men, ([Mean±SD] age 61 ± 10 years, BMI 28 ± 4 kg/m2). Quetiapine reduced the apnea/hypopnea index (primary outcome) versus placebo (20±12 vs. 27±16 events/h, p=0.02), arousal index (25±9 vs. 32±16 arousals/h, p=0.02), and increased sleep efficiency (87±9 vs. 80±11, p< 0.01) without worsening hypoxemia (e.g., mean overnight SpO2 94.5±1.5 vs. 94.7±1.2 %, p=0.42). However, next morning vigilance (e.g., median reaction time 382±84 vs. 336±48ms, p=0.02) and driving simulator performance (e.g., steering deviation 95±54 vs. 73±39, p=0.02) were impaired with quetiapine versus placebo. Conclusion Consistent with a hypnotic effect, a single night low dose of quetiapine reduces OSA severity as measured via the apnea/hypopnea index and increases sleep efficiency without worsening overnight hypoxemia. However, there is evidence of next day impairment in vigilance and driving simulator performance Support (if any) This study was funded by a National Health and Medical Research Investigator Grant (PI Eckert 1196261).