Adherence
CPAP therapy for obstructive sleep apnea requires different minimum nightly durations to normalize subjective sleepiness (4 hours), objective sleepiness (6 hours), and functional status (7.5 hours).
If you use CPAP for sleep apnea, 'enough' depends on what you want to fix. To feel less sleepy, 4 hours might be enough. To feel less sleepy objectively, aim for 6 hours. To fully restore your daily functioning and quality of life, you likely need 7.5 hours. Consistency is key; skipping nights reverses benefits.
Thresholds above which further improvements were less likely relative to nightly duration of CPAP were identified for Epworth Sleepiness Scale score (4 hours), Multiple Sleep Latency Test (6 hours), and Functional Outcomes associated with Sleepiness Questionnaire (7.5 hours).
Why this rating
Multicenter, quasi-experimental study with a large cohort (n=149) and rigorous statistical analysis (piecewise regression), though not a randomized controlled trial of adherence itself.
Source
Relationship Between Hours of CPAP Use and Achieving Normal Levels of Sleepiness and Daily Functioning
Terri E. Weaver et al. · SLEEP · 2007
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