Comment on a draft report by Agency for Healthcare Research and Quality (AHRQ) before the public comment period closes on April 23, 2021.
Studies are highly inconsistent as to how they define breathing measures during sleep studies and OSA itself. Insufficient evidence exists to assess the validity of AHI as a surrogate or intermediate outcome for long-term clinical outcomes. Until such validation has been conducted, it cannot be assumed that changes (e.g., improvements) in intermediate or surrogate outcomes are correlated with long-term clinical outcomes.
The published evidence mostly does not support that CPAP prescription affects long-term, clinically important outcomes. Specifically, with low SoE RCTs do not demonstrate that CPAP affects all-cause mortality, various CV outcomes, clinically important changes in psychosocial measures, or other clinically important outcomes. When NRCSs are combined with the RCTs there is the suggestion that CPAP reduces the risks of all-cause mortality (low SoE); other conclusions are not changed. The low SoE for these outcomes suggests that we have limited confidence that the summary estimates are close to the true effect.
Studies did not adequately address whether effects of CPAP vary based on disease severity (e.g., as assessed by AHI), symptoms (e.g., as assessed by sleepiness scales), other patient characteristics, different features or modes or CPAP, or different criteria or definitions of sleep measures or OSA diagnosis.
Additional studies are needed before we have a clear understanding of the potential effects of CPAP on long-term outcomes for patients with OSA, whether any particular group of patients may benefit to a greater or lesser degree from CPAP treatment or whether of AHI (and/or other breathing measures) are valid intermediate or surrogate measures of clinical outcomes.Comment on the draft report here