The non-benzodiazepine sedative hypnotic (NBSH) eszopiclone improves polysomnogra- phy (PSG) quality and continuous positive airway pressure (CPAP) adherence. It is unclear whether zolpidem has the same effect and neither NBSH has been studied in populations with milder forms of obstructive sleep apnea. Materials and Methods: We performed a retrospective analysis on patients undergoing level I PSG at our institution. Patients are pre-medicated with NBSHs at the discretion of the sleep physician. We compared PSG/CPAP titration quality and sub- sequent CPAP adherence for patients receiving NBSHs or no pre-study medication. We adjusted for obstructive sleep apnea pre-test probability (PTP), arousal threshold, and other factors showing differences at baseline. Results: Data on 560 patients were analyzed. Mean age and body mass index were 42.2 ± 10.1 and 28.8 ± 4.5, respectively.

Median apnea hypopnea index was 12.9 (6.4–25.3), 100 (18.0%) patients had normal studies, 97 (17.3%) were split, and 457 (81.6%) had a respiratory low-arousal threshold. After adjusting for differences at baseline, neither NBSH was associ- ated with sleep efficiency, wake after sleep onset, or total sleep time on PSG. After adjustment, patients receiving eszo- piclone had a higher apnea hypopnea index at the final CPAP pressure (β = 14.2; 95% confidence intervals (CI) 7.2–21.2; p