Patient characteristics and arousal threshold in central sleep apnea

Abstract

Introduction: The aetiology of central sleep apnea (CSA) remains incompletely understood. While proposed mechanisms exist for those with secondary causes, a complete understanding of primary CSA remains lacking. Here we describe the characteristics of patients in our centre with primary and secondary CSA, and the possible role of arousal threshold. Methods: A retrospective study was conducted across patients undergoing full overnight diagnostic polysomnography (PSG) at Concord Repatriation General Hospital (CRGH) in Sydney, Australia from October 2013 to July 2018 with predominant CSA based on AASM criteria. Patients were classified as having either primary or secondary CSA after review of medical records to identify any known contributing co-morbidities or medication/substance use. Patient demographics, PSG characteristics and arousal threshold (Edwards, B.A. et al. AJRCCM 2014; 190(11):1293-300) were recorded. Results: 33 patients meeting criteria for predominant CSA were identified, 32 (97.0%) of which were male. 14 patients (42.4%) had primary CSA and 19 (57.6%) secondary CSA. Comparison between groups showed patients with primary CSA were more likely to be younger (54.6 years vs 74.1 years, p Conclusion: Patients with primary CSA were more likely to be significantly younger in age and have a lower arousal threshold, possibly contributing to instability of ventilatory control and propagation of central events.