Long-term adherence to continuous positive airway pressure in patients with rapid eye movement-only obstructive sleep apnea: a prospective cohort study

Background: Obstructive sleep apnea (OSA) during rapid eye movement (REM) sleep is a special form of OSA that occurs predominantly during REM sleep. No study has assessed the long-term adherence to continuous positive airway pressure (CPAP) among patients with REM-only OSA. To objectively assess the long-term adherence to CPAP therapy among patients with REM-predominant (REM-only) OSA. Methods: This was a prospective observational cohort study that included consecutive patients who were diagnosed with OSA. Patients were divided into the following two groups: (I) REM-only OSA [an apnea hypopnea index (AHI) of >= 5, with a REM-AHI/NREM-AHI of >2, an NREM-AHI of < 15, and a minimum of 15 min of REM-sleep duration], and (II) non-stage specific OSA. Follow-up was performed at 1, 6 and 12 months after the initiation of CPAP-therapy. Results: The study included 175 patients; 30 met the criteria for REM-only OSA, and the remaining patients constituted the non-stage specific OSA group. The number of hours of CPAP use per day was significantly lower in the REM-only OSA group at 1, 6 and 12 months compared to the non-stage specific OSA group. At 12 months, the number of hours used per day was 3.8 +/- 1.8 and 5.1 +/- 2.1 hours in the REM-only and non-stage specific OSA groups, respectively (P=0.003). Approximately 80% of the enrolled participants in both groups were still using CPAP at the end of the study; 23.3% of REM-only OSA patients met the criteria for good adherence (>4 hours/day), and 56.7% met the criteria for partial adherence. Conclusions: CPAP adherence is lower among patients with REM-only OSA compared to patients with non-stage specific OSA.