BACKGROUND AND OBJECTIVES

Obstructive sleep apnea (OSA) during rapid eye movement (REM) stage of sleep is gaining importance in recent years. This study was done to determine the proportion of REM-related OSA and its associated polysomnographic features.

METHODS

One hundred forty-two patients were included in the study. REM-related OSA was defined based on previously established broad and strict criteria (REM apnea-hypopnea index [AHI]/non-REM [NREM] AHI ratio ≥2 and REM AHI >5 with NREM AHI <5, respectively), and its association with polysomnographic features was studied using appropriate statistical tools.

RESULTS

The proportion of REM-related OSA in the study was 56.3% and 25.3% as per broad and strict criterion, respectively. The REM-related OSA group had a mean younger age (47.4 ± 13.2 years) as compared to NREM-related OSA group (52.6 ± 15.8 years). Females (34 out of 45; 75.6%) were more likely to have REM-related OSA as compared to males (46 out of 107; 47.4%). Supine AHI, arousal index, oxygen desaturation index, length of the longest event, and the lowest oxygen saturation recorded during sleep had a significant association with REM-related OSA. 74% of patients with overall AHI <5 and 87% patients with overall AHI 5 to 15 satisfied the criteria for REM-related OSA as per broad criterion.

CONCLUSION

REM-related OSA was quite prevalent in the study population (56.3%) and was more common in the mild and moderate severity subgroups of OSA.