0565 THE IMPACT OF UPPER AIRWAY STIMULATION ON THE REM AHI

Abstract Introduction: The burden of obstructive sleep apnea (OSA) in REM sleep, as opposed to NREM sleep has been independently associated with hypertension and metabolic risk. These observations are relevant to treatment. A significant number of patients, treated with positive pressure therapy discontinue therapy after the initial 3 -4 hours of use, leaving the time when REM sleep is most prominent (the last third of the sleep period) untreated. Upper Airway Stimulation (UAS) via unilateral implantation of a phasic hypoglossal nerve stimulation device is an alternative for treating moderate to severe OSA. The reported nightly use (subjective and objective) is closer in duration to the total sleep time. The primary aim of this report was to assess the impact of UAS on REM OSA in the Stimulation Therapy for Apnea Reduction (STAR) Trial cohort at 36 months. Methods: Participants (n=116) were enrolled in a multicenter prospective phase III trial evaluating the efficacy of UAS for moderate to severe OSA. Polysomnography (PSG) was performed at baseline, 12 months and at 36 months’ post implantation of the UAS system (Inspire Medical Systems, Minnesota, USA). Attended PSG assessed the overall apnea hypopnea index (AHI) in addition to the AHI in REM and NREM. Self-reported nightly adherence data were collected. Results: Of 126 enrolled participants, 116 (92%) completed 36-month follow-up evaluation per protocol; 98 participants additionally agreed to a voluntary 36-month PSG. UAS reduced the AHI from 32 ± 18.5 at baseline to 15.3 ± 16.1* and 11.3 ± 13.8* at 12 and 36 months, respectively. A similar effect of UAS was observed on the NREM and REM AHI: Baseline REM AHI 28.9 ± 17.4 to 14.7 ± 16.1* (12 months) and 7.7 ± 12.8* (36 months); Baseline NREM AHI 32.3 ± 12.6 to 15.3 ± 16.8* (12 Months) to 11.5 ± 14.3* (36 months). Self-report nightly device usage was 81%. *p < 0.05. Conclusion: UAS effectively treats the REM AHI, that may be an important independent mediator of cardiovascular and metabolic risk. This therapy is associated with a high level of self-reported nightly usage. Support (If Any): Inspire Medical Systems, Minnesota, USA.