Does sleep apnea home-evaluation and potential treatment improve quality of life in patients with atrial fibrillation? Rationale and design of the VIR-SAAF study

Background Obstructive sleep apnea (OSA) is a common and modifiable risk factor for atrial fibrillation (AF), yet it remains frequently unrecognized and undertreated. Evidence from randomized trials investigating continuous positive airway pressure (CPAP) in AF is inconclusive, while observational studies suggest that OSA treatment may reduce AF recurrence and symptom burden. Despite guideline recommendations to consider OSA screening, no consensus exists on optimal screening strategies, and traditional diagnostic methods are impractical for large-scale implementation. Purpose The VIR-SAAF trial aims to determine whether home-based OSA screening and referral for potential treatment improve quality of life, health behaviors, and AF-related outcomes compared with standard care in patients with AF. Methods VIR-SAAF is a national, investigator-initiated, decentralized randomized clinical trial enrolling adults with paroxysmal or persistent AF across Denmark. After completing baseline questionnaires, participants are randomized 2:1 to home-based screening for OSA or to no screening (standard care). The intervention group receives a package containing a validated device for one night of OSA testing and a wearable activity sensor, and performs heart rhythm monitoring using a smartphone-based photoplethysmography application. Participants with moderate-to-severe OSA or clinically significant symptoms are referred to sleep specialists for diagnostic confirmation and potential treatment. The control group completes the same digital questionnaires and monitoring without OSA evaluation. The primary endpoint is the between-group difference in change from baseline to 18 weeks in quality of life assessed by the Atrial Fibrillation Effect on QualiTy-of-life (AFEQT) questionnaire. Secondary endpoints include changes in AF-load, physical activity, and AF symptom severity (AFSS), while exploratory endpoints include sleep quality, digital health literacy, and long-term clinical outcomes from registry linkage. Results The first randomization took place on 5 December 2024. As of the current reporting period, 224 participants have been randomized. Conclusion VIR-SAAF is the first randomized trial to evaluate OSA screening itself as an intervention in AF. Using a fully decentralized design that integrates validated digital tools for sleep, rhythm, and behavior monitoring, the trial will provide novel evidence on whether systematic OSA screening can improve patient-centered outcomes and inform the role of OSA evaluation in contemporary AF management.