0518 Mortality in Patients with Central Sleep Apnea using Adaptive Servoventilation Therapy- A Population Based Study

Abstract

Introduction: Adaptive servoventilation (ASV) is contraindicated in CSA patients with symptomatic heart failure and ejection fraction< 45%, even though has been shown to provide significantly better control of central sleep apnea (CSA) and may be better tolerated than other treatment modalities, as a recent multi-center randomized controlled trial demonstrated increased mortality in this group of patients using ASV. In this population-based study, we evaluated the impact of ASV on mortality in all CSA subtypes. Methods: All cases of CSA (n=1,237) from Olmsted County, MN were identified utilizing the Rochester Epidemiology Project database and a further search was performed to find patients commenced on ASV. The primary outcome assessed was change in the rate of hospitalization 2 years before and after ASV was prescribed. Mortality data was collected for the cohort for the entire follow-up period available. Patients with a follow-up duration of <1 month pre- and/or post-ASV were excluded. Manual review of charts was performed to obtain all relevant data. Results: A total of 309 patients were included (mean age 68.0 ± 14.6 years, 80.3% male, 97.1% White, mean body mass index (BMI) 31.7 ± 6.5 kg/m2, mean apnea-hypopnea index AHI 41.8 ± 26/ hour, mean central apnea index 14/hour). Treatment-emergent CSA (73%) was the most common subtype. Ninety-one patients (29%) died during a median follow up of 6.35 years (range: 60 days to 10.7 years). In multivariate analyses, age (HR 1.07, 95%CI:1.03?1.10), cardiac comorbidities (HR 1.72, 95%CI:1.02?2.89) and CSA secondary to cardiac cause with/without Cheyne Stokes breathing (compared to treatment-emergent CSA) (HR 1.69, 95%CI:1.03?2.77) were significantly associated with an increased risk of death (all p<0.05). There was a trend toward decreased risk of death with adherence to ASV of ≥4hours/night on ≥70% nights at 1 month (HR 0.64, 95%CI:0.41?1.0, p=0.05). Conclusion: The mortality rate in this group of patients with predominantly treatment-emergent CSA was high, with a trend toward reduced risk of death in those adherent to ASV at 1 month.