0164 Evidence Suggesting Early Airway Collapse as Cause of Spontaneous Arousals

Abstract

Abstract Introduction Spontaneous arousals can occur in response to a number of stimuli like noise, movement, hypoxia, or airway obstruction. Some arousals occur “spontaneously” and in individuals donning a hyper-arousable phenotype, spontaneous arousals can dominate the sleep architecture. While arousal mechanisms for some stimuli have been well described, there is a profound lack of knowledge to explain spontaneous arousals. During clinical testing of a device that was designed by SleepMethods, Inc. to anticipate obstructive sleep apnea events by the ability to sense minute airway caliber changes, it was noted, incidentally that the device would signal impeding airway collapse but a spontaneous arousal followed the signal before an obstructive airway event ever developed. This phenomenon was observed many times within and between subjects, suggesting the possibility that very early airway changes are causing “spontaneous arousals” Methods Ten adults (7M;3F) aged 18-80y/o (avg. 54.7y/o) with a known AHI ≥ 15/hr (avg. AHI = 42.6/hr) underwent 1 overnight PSG recording while wearing the device. Patients were required to forego their usual CPAP therapy on the night of study in efforts to expose the device to an adequate number of total obstructive events (defined as apneas and hypopneas; RERAs and snores were excluded). Standard PSG analysis was performed. Scoring rules were applied to determine whether signals were true/false positives and/or true/false negatives based on pre-clinical data showing anticipation accuracy for up to 45 seconds prior to an obstructive airway event. Signals designed to herald obstructive events were noted, incidentally, appearing prior to spontaneous arousals. Results Preliminary results suggest that early phases of airway collapse, as the airway progresses from patency to clinically significant obstruction, are causing EEG arousals which, by current standards, are considered “spontaneous”. Because these findings were incidental to another primary purpose of the clinical study, data analysis is in early stages but currently suggesting at least an associative relationship. Conclusion If final data analysis shows statistically significant correlation between early airway collapse and “spontaneous arousals”, it may have tremendous implications for patients with hyper-arousability, insomnia, and/or pathologically elevated spontaneous arousal indices by proposing therapies aimed at airway patency maintenance. Support N/A