Single-use suvorexant for treating insomnia during overnight polysomnography in patients with suspected obstructive sleep apnea: a single-center experience

Abstract

Purpose: Although patients with suspected obstructive sleep apnea (OSA) might suffer difficulty in falling asleep during overnight polysomnography (PSG), standard hypnotics to obtain sleep during PSG have not been established. The aim of this study was to investigate the safety and efficacy of a new hypnotic agent, suvorexant, a dual orexin receptor antagonist, for insomnia in suspected OSA patients during in-laboratory PSG.

Patients and methods: An observational study was conducted during PSG for 149 patients with suspected OSA who had no insomnia at home. Patients with difficulty in falling asleep during PSG were optionally permitted to take single-use suvorexant. Patients with residual severe insomnia (>1 hour) after taking suvorexant were permitted to take an add-on use zolpidem. Clinical data and sleep questionnaire results were analyzed between a no insomnia group (without hypnotics) and an insomnia group (treated with suvorexant).

Results: Among 84 patients who experienced insomnia during PSG and required hypnotics (the insomnia group; treated with suvorexant), 44 (52.4%) achieved sufficient subjective sleep with single-use of suvorexant, while the other 40 (47.6%) required suvorexant plus zolpidem. An apnea hypopnea index (AHI) of ≥5 was observed in 144 out of 149 patients with predominantly obstructive respiratory events. Among those patients, 70.8% in the no insomnia group and 63.1% in the insomnia group had severe OSA. Regarding both subjective sleep time and morning mood, significant differences between the no insomnia group and the insomnia group were not observed. No patient taking suvorexant had an adverse event, such as delirium or falling.

Conclusion: Single-use suvorexant seems to be a safe and effective (but mild) hypnotic agent for suspected OSA patients with insomnia during in-laboratory PSG.

Keywords: insomnia; natural sleep; obstructive sleep apnea; polysomnography; suvorexant; zolpidem.

Figure 1

Flowchart of patient selection. Notes: Of 190 patients who were screened, 65 were assigned to the no insomnia group (without hypnotics) and 84 to the insomnia group (treated with suvorexant). In the insomnia group, 40 patients required zolpidem after suvorexant. (+) = Yes, (−) = No. Abbreviations: DBS, deep brain stimulation; OSA, obstructive sleep apnea; PSG, polysomnography.

Figure 2

Summary of sleep questionnaire responses: subjective sleep time compared with home (A), and morning mood compared with home (B). Notes: The majority of the patients answered the subjective sleep time was longer or no change and morning mood was better or no change compared to those at home in all the groups. There were no significant differences between the no insomnia group and the insomnia group and between the suvorexant only group and the suvorexant+zolpidem group regarding both subjective sleep time and morning mood.