Antifibrotic therapies reduce mortality and hospitalization among Medicare beneficiaries with idiopathic pulmonary fibrosis

BACKGROUND: Additional real-world studies are needed to more fully elucidate the effectiveness of antifibrotic treatment in slowing the progression of idiopathic pulmonary fibrosis (IPF). OBJECTIVE: To compare mortality and hospitalization between Medicare beneficiaries with IPF who initiate antifibrotic therapy and those who did not receive treatment. METHODS: A retrospective observational study of Medicare beneficiaries using the 100% Medicare Research Identifiable File was conducted. We included patients aged 67 years and over diagnosed with IPF (≥ 1 inpatient or ≥ 2 outpatient claims with IPF diagnosis) during the study period (January 1, 2010-December 31, 2017). Patients who initiated antifibrotic treatment (pirfenidone or nintedanib) between October 15, 2014 (FDA approval date) and December 31, 2017 (ie, treated patients) were compared with those who did not receive treatment during a historical period (January 1, 2012-October 14, 2014) before the availability of antifibrotics (ie, untreated historical controls). Patients were matched by propensity score, and the outcomes, mortality, and hospitalization (all cause and respiratory related) were compared using a Cox proportional hazards model. RESULTS: We identified 4,641 treated patients and 4,641 propensity score-matched controls who met all study criteria; 352 treated patients who lacked matches were excluded from the study. Cox regression analysis of treated patients vs matched controls showed a significantly lower risk of mortality (HR = 0.62, 95% CI = 0.57-0.68); lower risk of hospitalization (HR = 0.71, 95% CI = 0.67-0.76; HR = 0.70, 95% CI = 0.64-0.76); and lower rate in number of hospitalizations per month (incident rate ratio [IRR] = 0.65, 95% CI = 0.60-0.71; IRR = 0.65, 95% CI = 0.58-0.73). CONCLUSIONS: This study suggests that treatment with antifibrotics may confer a survival benefit and protection against all-cause and respiratory-related hospitalization for IPF patients.