0565 Long-Term Survival in Veterans with Sleep Apnea

Abstract

Introduction: Untreated obstructive sleep apnea (OSA) decreases longterm survival. OSA treatment, either continuous positive airway pressure (CPAP) or surgery, appears to improve survival. However, the duration of these survival benefits is unclear. We tested the association between OSA treatment and survival in a large, long-term cohort of veterans. Methods: This retrospective cohort study included all adult veterans diagnosed with OSA in any Veterans Affairs (VA) inpatient facility 1993?2013 or outpatient facility 1997?2013. Subjects were identified by ICD-9 diagnosis codes in VA inpatient and outpatient files. OSA treatment (untreated versus prescribed CPAP versus surgery) was determined by ICD-9 or CPT procedure codes. Patients without a procedure code were considered untreated. Vital status as of 2/1/2017 was extracted from VA Vital Status Files. The Charlson Comorbidity Index was calculated from ICD-9 diagnosis codes from two years prior to OSA diagnosis. Survival was compared by OSA treatment (untreated versus prescribed CPAP versus surgery) using Kaplan-Meier estimates and mortality hazard with Cox regression, adjusting for age, sex, body mass index (BMI), comorbidity, and year of diagnosis. Results: The cohort included 638,029 untreated, 231,928 CPAP, and 6,977 surgery patients (N=876,934) with mean age 61+/-13 years, mostly male (96%), and some obese (48% BMI>30). The majority (76%) was diagnosed with OSA since 2010. Survival at 5 years was 76% for untreated, 84% for CPAP, and 83% for surgery (P<0.001 untreated versus treated [CPAP or surgery]), while survival at 20 years was 34% for untreated, 38% for CPAP, and 48% for surgery (P<0.001, untreated versus treated). The overall adjusted mortality hazard ratio for CPAP versus untreated was 0.79 (95%CI:0.78?0.80,P<0.001); for surgery versus untreated was 0.85 (95%CI:0.81?0.90,P<0.001); and for CPAP versus surgery was 0.93 (95%CI:0.88?0.97,P=0.004). Conclusion: CPAP prescription and surgery each confer a survival advantage over no treatment for OSA. CPAP provides an overall survival advantage over surgery, but surgery appears to provide a long-term survival advantage over CPAP. These results suggest that OSA patients who do not use CPAP or stop using CPAP may benefit from surgery evaluation.