AHRQ Report on CPAP Efficacy Gets Push Back from Sleep Medicine Industry

Jared Kaltwasser

A report by the Agency for Healthcare Research and Quality suggested existing evidence on continuous positive airway pressure devices is not robust enough to be clinically meaningful.

Major players in the sleep medicine industry are pushing back against a draft report from the Agency for Healthcare Quality and Research that found there is insufficient evidence for continuous positive airway pressure (CPAP) devices leading to clinically meaningful long-term benefits in patients with obstructive sleep apnea.

The 155-page draft report, released last month, was based on a review of 47 studies that evaluated the benefits of CPAP machines in patients with obstructive sleep apnea. AHRQ, a healthcare quality research agency, is part of HHS.

“The published evidence mostly does not support that CPAP prescription affects long-term, clinically important outcomes,” the report concluded. “Specifically, with low SoE [strength of evidence] RCTs [randomized controlled trials] do not demonstrate that CPAP affects all-cause mortality, various CV [cardiovascular] outcomes, clinically important changes in psychosocial measures, or other clinically important outcomes.”

Obstructive sleep apnea affects an estimated 25 million adults in the United States, according to the American Academy of Sleep Medicine. The disease is characterized by the collapse of the airway behind the tongue during sleep. The disruption of airflow can lead to poor sleep quality as well as a range of more serious long-term impacts, such as cardiovascular stress. CPAP has been promoted and prescribed as way to treat obstructive sleep apnea for decades. It keeps the airway open by mechanically increasing air pressure in a patient’s airway, thereby preventing collapse.

In a conference call with investors last month, Mick Farrell, M.S., MBA, the chief executive of ResMed, a CPAP device maker, disputed AHRQ’s characterization of the existing literature, saying there is plenty of evidence to support the benefits of CPAP.

“While we respect the work of AHRQ, we, along with many other academic research-focused institutes and practicing physician groups, believe that they bypassed a generation of data in real-world evidence that needs to be taken into account, along with their own select group of RCTs in the draft report,” he said.

Farrell said peer-reviewed evidence suggests CPAP use leads to a reduction in heart attack and hypertension as well as a reduction in the incidence of solid-cell cancer tumors, outcomes he said are logical results of eliminating hypoxia through use of CPAP.

In its draft report, AHRQ does not dispute that such studies exist, but rather takes issue with their methodology, suggesting the studies generally have low strength of evidence (SoE). The agency noted that obstructive sleep apnea severity and response to treatment are typically gauged using the apnea-hypopnea index, a measure of the number of apnea and hypopnea events that occur during sleep. Yet, the AHRQ report said there “is no standard definition of this measure,” meaning that existing literature is “highly inconsistent” in how it evaluates breathing. Moreover, the report said it is not clear whether AHI is even a valid surrogate measure of clinical outcomes.

“Until such validation [of AHI] has been conducted, it cannot be assumed that changed (e.g., improvements) in intermediate or surrogate outcomes are correlated with long-term clinical outcomes,” the report stated.

David Schwartz, D.D.S., president of the American Academy of Dental Sleep Medicine, said periodic reviews like that of AHRQ are “essential” to inform clinical practice and improve patient care.

“However, the conclusions drawn in this report do not reflect the totality of available evidence and do not consider outcomes most physicians and patients would consider clinically important,” he told Managed Healthcare Executive. “Millions of patients who suffer from obstructive sleep apnea have benefited from the use of CPAP machines and the less cumbersome oral appliance therapy. To suggest otherwise has the potential for detrimental repercussions to their health.”

The public comment period for the draft report ended April 23. The agency is now in the process of reviewing comments received from stakeholders. An agency spokesperson said the comments will be published along with the release of the final report.