OSA Endotypes: What Are They and What Are Their Potential Clinical Implications?
Purpose of the Review
To review critically the different mechanisms, or endotypes, causing obstructive sleep apnea (OSA) in individual patients, and their potential implications for management.
Currently, at least four underlying mechanisms that contribute to OSA have been identified, namely a compromised upper airway anatomy, a poor pharyngeal muscle responsiveness, respiratory control instability (high loop gain), and a low arousal threshold (wake up too easily); the relative contributions of these four traits in an individual form their endotype. Endotypes provide therapeutic targets that may facilitate development of novel therapies, can predict treatment response to non-CPAP therapies, and may explain clinical phenotypes. Endotyping is currently restricted to specialized research laboratories, but newer methods relying on standard polysomnography may soon allow routine assessment of endotypes as part of clinical practice.
Endotyping promises to transform the current one-size fits-all OSA management into an individualized precision medicine approach in the future.
KeywordsObstructive sleep apnea Endotype Phenotype Pathogenesis Mechanisms Management
Compliance with Ethical Standards
Conflict of Interest
Christopher N. Schmickl declares no conflicts of interest.
Robert L. Owens reports personal fees from Novartis, personal fees from ResMed, personal fees from Itamar.
Bradley A. Edwards grants from Heart Foundation of Australia.
Atul Malhotra relinquished all outside personal income in 2012 as an Officer of the American Thoracic Society. Resmed provided a philanthropic donation to the UC San Diego in support of a sleep center.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Robert L. Owens is supported by NHLBI R01 HL142114–01. Bradley A. Edwards is supported by a Heart Foundation of Australia Future Leader Fellowship (101167).
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major Importance
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