Thomas RJ, Bianchi MT. Urgent need to improve PAP management: the devil is in two (fixable) details. J Clin Sleep Med. 2017;13(5):657–664. DOI: 10.5664/jcsm.6574
Several high-profile, large prospective sleep apnea therapy trials have failed to meet expected outcomes. Each theoretically had the power to positively influence practice, but instead have cast doubt on the staple of our field: positive airway pressure. Struggling to navigate these findings, experts have invoked explanations ranging from inadequate use, too-short duration of therapy, overwhelming disease pathophysiology, treatment initiated too late in evolution of disease, and unknown pathophysiological constructs. Although these are important questions to advance our field, there are two arguably more fundamental details that must be addressed.
First, the efficacy of continuous positive airway pressure (CPAP)—or adaptive ventilation in the case of the SERVE-HF study—remains unquestioned, either via titration data or via machine data download thresholds, despite emerging data suggesting otherwise. Second, off-positive airway pressure (PAP) sleep time is not measured or considered, yet it must be to understand overall PAP effectiveness. We propose that these two aspects must be addressed urgently, before we seek explanations beyond these fundamental aspects of PAP therapy to reconcile negative trial outcomes.
We do not measure sleep apnea events during off-PAP sleep, which for some patients can represent well over 50% of their total sleep duration. For over a decade we have known that event recurrence varies from PAP withdrawal studies, and the surgical literature has clearly indicated the need for measuring all of sleep to understand PAP effectiveness given the issues surrounding compliance.