Comparing the Characteristics of REM and Positional Obstructive Sleep Apnea Phenotypes Among Jordanian Population

Background Obstructive Sleep Apnea (OSA) is a common cause of sleep disordered breathing, yet it is characterized by several phenotypes. In this study, we aimed to evaluate the differences in the demographics, comorbidities and polysomnographic features between Positional OSA (POSA) and Rapid Eye Movement OSA (REM predominant OSA) in a Jordanian sample. Methods A total number of 1,092 patients were referred for polysomnography (PSG) at the Jordan University Hospital (JUH) sleep lab. Patients were recruited between June 2016 and March 2022 based on hospital chart review. Any patient above the age of 18, underwent complete polysomnography at JUH lab and had overall AHI higher than 5 was included in this analysis. Pediatric patients (age 5, an overall AHI severity at least 1.4 times the non-supine severity (Overall/NS-AHI) and a minimum amount of time (i.e., 20 min) in the supine and non-supine positions . REM predominant OSA was defined as an overall AHI of ≥ 5 and a ratio of the AHI during REM sleep to the AHI during NREM sleep of ≥ 2. Results The prevalence of POSA and REM predominant OSA was 41.7% and 26.3%, respectively. In comparison to REM predominant OSA patients, POSA patients had higher male sex prevalence (54.1% vs. 31.9%), severer OSA (65.9% vs. 18.6%), and higher mean age (57.65 ± 14.43 vs. 53.10 ± 14.77). Moreover, total AHI (45.30 ± 30.33 vs. 18.27 ± 12.99), left and right AHI, arousal index (41.33 ± 23.34 vs. 21.70 ± 13.23), and the time SpO2 was below 90% (28.75 ± 32.79 vs. 18.80 ± 27.97) were significantly higher among POSA patients. While, the mean SpO2 awake (92.06 ± 4.29 vs. 93.30 ± 2.96), SpO2 NREM (89.86 ± 6.03 vs. 91.88 ± 3.41), SpO2 REM (87.98 ± 8.42 vs. 89.78 ± 6.06) and SpO2 nadir (73.58 ± 14.05 vs. 78.37 ± 11.12) were significantly lower in the POSA group when compared to the REM OSA group. Conclusion There were several significant differences between REM predominant OSA and POSA.