Functional Outcomes in Patients with REM-Related Obstructive Sleep Apnea Treated with Positive Airway Pressure Therapy

Study Objectives: To evaluate functional outcomes in adults with REM-related obstructive sleep apnea (OSA) treated with positive airway pressure (PAP) therapy. Design: Retrospective observational study. Setting: Outpatient sleep clinic. Patients: 330 adults (171 males) with OSA receiving PAP therapy, including 130 with REM OSA and 200 with OSA not restricted to REM. Measurements and Results: REM OSA was defined as a REM apnea-hypopnea index (AHI)/NREM AHI > 2 and NREM AHI < 15. Patients had baseline and post-PAP functional outcomes, including Epworth Sleepiness Scale (ESS), Fatigue Severity Scale (FSS), Patient Health Questionnaire-9 (PHQ-9), and Functional Outcomes Sleep Questionnaire (FOSQ) scores. We compared functional outcomes, demographic, clinical and polysomnographic features, and PAP adherence in patients with REM OSA and OSA not restricted to REM. Female gender was significantly more common in REM OSA. Age, BMI, neck girth, and baseline ESS, FSS, PHQ-9, and FOSQ were similar between groups. Smoking history and comorbid disorders were also similar except for a higher prevalence of depression and cardiovascular disease in OSA not restricted to REM. All functional outcomes improved significantly after PAP therapy in both groups. Change from baseline to post treatment was similar for all functional outcomes between groups. Conclusions: The study is the first addressing clinical outcomes in REM OSA using validated measures. Functional outcomes in patients with REM OSA improve after treatment with PAP therapy comparable to that observed in patients with OSA not restricted to REM.