The relationship between sleep quality, daytime sleepiness, and rapid eye movement obstructive sleep apnea (REM-OSA)

Purpose: The prevalence of rapid eye movement obstructive sleep apnea (REM-OSA) varies among reports. It remains unclear whether or not patients with REM-OSA experience more severe daytime sleepiness and poorer sleep quality than those with sleep-stage-independent obstructive sleep apnea (IND-OSA). We investigated the prevalence of REM-OSA in a Korean population sample and determined whether or not REM-OSA was associated with poor sleep quality and daytime sleepiness.

Method: In this retrospective study. we defined "REM-OSA 1" as an apnea-hypopnea index (AHI) ≥ 5 and AHI_REM/AHI_NREM ratio ≥ 2. Patients who also had an AHI_NREM < 15 were classified as "REM-OSA 2" and those with an AHI_NREM < 8 and REM sleep duration ≥ 10.5 min were classified as "REM-OSA 3." Patient characteristics, Epworth Sleepiness Scale (ESS), Pittsburgh Sleep Quality Index (PSQI), and polysomnography variables were compared between the REM-OSA and IND-OSA groups.

Results: Among 483 patients, the prevalence rates of REM-OSA 1-3 were 10.3%, 5.5%, and 2.2% respectively. OSA severity was significantly lower in REM-OSA 1-3 than in IND-OSA. The proportion of women was significantly higher in REM-OSA 1-3 than IND-OSA groups. Patients with REM-OSA 2 and 3 had a significantly lower body mass index than those with IND-OSA. Patients with moderate-to-severe REM-OSA had significantly higher PSQI scores than those with IND-OSA. The AHI_REM was significantly correlated with the ESS and PSQI scores.

Conclusions: Despite the relatively low prevalence and severity of REM-OSA, it may reduce sleep quality and increase daytime sleepiness in some patients.