Zolpidem and Eszopiclone Pre-medication for PSG: Effects on Staging, Titration, and Adherence

The non-benzodiazepine sedative hypnotic (NBSH) eszopiclone improves polysomnography (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.

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 subsequent 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.

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 associated with sleep efficiency, wake after sleep onset, or total sleep time on PSG. After adjustment, patients receiving eszopiclone had a higher apnea hypopnea index at the final CPAP pressure (β = 14.2; 95% confidence intervals (CI) 7.2-21.2; p < 0.001) and were more likely to have an unacceptable titration (odds ratio (OR) = 6.6; 95% CI 2.0-21.0; p = 0.002). When only split-night studies were examined, there were no differences in any adherence variables across or between categories.

In a population with predominantly mild obstructive sleep apnea, NBSHs did not improve PSG or CPAP titration quality and did not increase CPAP adherence. There was no difference in effect between eszopiclone and zolpidem.