0503 Rem Predominant Obstructive Sleep Apnea And Hypertension: A Cross-sectional Study In Clinical Sample

Abstract

Introduction It has been reported that REM-predominant OSA had different clinical features and risks for cardiovascular disease than NREM OSA. However, studies investigating the REM OSA and NREM OSA have inconsistent results. This study aimed to investigate the clinical features of REM OSA and NREM OSA and their associations with hypertension in patients with OSA. Methods Clinical and polysomnographic information were extracted from a database prospectively collected from 6,875 referrals for suspected sleep apnea from January 2009 to December 2016. Patients with REM or NREM less than 15 min were excluded. REM OSA was defined as the ratio (apnea-hypopnea index at REM divided to that at NREM) more than 2 where NREM OSA was defined as the ratio less than 0.5. The data were compared between REM OSA and NREM OSA. The association between REM OSA/NREM OSA and hypertension was analyzed with logistic regression and presented as odds ratio (OR). Results Among 5308 patients with OSA, 1763 (33%) were REM OSA and 460 (9%) NREM OSA. The REM OSA were younger (P=0.006), more female (P<0.001), and had higher body mass index (P<0.001) while NREM OSA had higher neck circumference (P<0.001), higher percentage of active smoker (P=0.003), alcohol drinking (P=0.001), diabetes (P=0.014) and chronic kidney disease (P=0.37). The percentage of hypertension was similar between REM OSA and NREM OSA (24% vs 25%). For the polysomnographic features, NREM OSA had higher AHI (either supine or non-supine), longer apnea duration, oxygen desaturation index and arousal index (all P<0.001). In REM OSA, the risk of hypertension increased with OR 1.46 and 2.41-fold for moderate and severe OSA, respectively, compared to mild OSA with the adjustment of age and gender. Such an association was not seen in NREM OSA. Conclusion The clinical and polysomnographic features of REM OSA were different from those of NREM OSA. REM OSA was associated with increased risk of hypertension while OSA was more severe. Support (If Any) National Taiwan University (project number NTU-ERP-104R8951-1, 105R8951-1, 106R880301); National Taiwan University Hospital (NTUH 105-S2998, 107-19).