Assessing the Physiologic Endotypes Responsible for REM- and NREM-Based OSA

Natural History of REM-OSA in Children and Its Associations with Adverse Blood Pressure Outcomes: A Longitudinal Follow-Up Study

“… 38 , 41 In fact, a recent study reported a higher arousal threshold in REM than NREM sleep in individuals with REM-OSA. 9 In our study, we observed a lower arousal index in those with REM-OSA at both baseline and follow-up. The arousal indexes were also generally higher at 10-year follow-up than baseline in all OSA subtypes, which was consistent with previous findings of decreasing arousal threshold with increasing age.…”

“… 9 A recent study demonstrated that individuals with REM-OSA displayed a significantly more collapsible airway in REM compared with NREM sleep, while individuals with NREM-OSA had a higher loop gain and lower ventilatory drive during obstructed breathing at arousal threshold during NREM sleep. 9 The increase in airway collapsibility during REM sleep is likely related to the characteristic muscle atonia during this period of sleep. 9 Pharyngeal dilators are important to maintain pharyngeal patency against factors that tend to collapse the airway.…”

“… 9 The increase in airway collapsibility during REM sleep is likely related to the characteristic muscle atonia during this period of sleep. 9 Pharyngeal dilators are important to maintain pharyngeal patency against factors that tend to collapse the airway. During sleep, the neuromuscular tone of the pharyngeal dilators is diminished making them less able to compensate.…”

“…This finding is consistent with a recent adult study. 9 The differences in the overall OSA severity between the two subtypes at follow-up likely have significantly modulated the effect of stage-dependent OSA on the BP outcomes. Moreover, the evaluation between REM-OSA and BP outcomes at follow-up was likely limited by the sample size.…”

“… 9 These factors, including upper airway collapsibility and muscle responsiveness, ventilatory control stability, and arousal threshold, change with age and disease status and therefore may influence the pattern of polysomnographic subtypes across age groups. 9 , 10 However, the natural history and clinical significance of sleep stage-dependent OSA have not been fully assessed.…”