Usage of adaptive servo-ventilation (ASV): results from the READ-ASV registry

<bold>Background and objectives</bold> Adaptive servo-ventilation (ASV) is used to treat central sleep apnea (CSA) and coexisting CSA-OSA (obstructive sleep apnea). Usage of therapy is key for achieving positive outcomes. This analysis describes therapy usage in a real-world population of patients with first-time ASV therapy. <bold>Methods</bold> 847 patients were enrolled from clinical routine between Sept 2017 and March 2021 in the prospective, multi-centre READ-ASV registry. Patients were categorised by indication for ASV therapy, as previously described. Therapy data and clinical data were collected at follow-up after 12 months. Disease-specific quality of life was assessed with the Functional Outcomes of Sleep Questionnaire (FOSQ) and the Epworth Sleepiness Scale (ESS). <bold>Results</bold> 545 patients had therapy data documented. Mean device usage was 5.36±2.17h/day. Usage in the different indications for ASV are shown in Fig 1. Changes in FOSQ scores from baseline to follow-up in patients with average usage <4h/day (n=119) and ≥ 4h/day (n=380) were 0.70±2.61 points and 1.19±2.53 points (p=0.143) and for ESS -1.32±4.35 (<4h/day; n=108) and -2.55±4.38 points (≥ 4h/day; n=341) (p=0.012). <bold>Conclusions</bold> Overall compliance with ASV therapy was good, this was seen throughout the main indications for ASV. Increased usage of ≥4h/day led to a statistically significant higher improvement in daytime sleepiness.