Efficacy of Antifibrotics in Idiopathic Pulmonary Fibrosis Associated to Emphysema

Abstract

Introduction: Idiopathic Pulmonary Fibrosis (IPF) is a progressive fibrotic interstitial lung disorder with poor prognosis. In some patients, IPF coexists with emphysema (CPFE). There is no clear data regarding antifibrotics' (AF) efficacy in this subgroup. Aim: Assess AF efficacy in CPFE patients, compared to IPF. Materials and Methods: Patients' data was retrospectively collected, including smoking habits, comorbidities, pulmonary function tests (PFT), thoracic CT imaging and AF prescription. Evaluated outcomes were overall survival and disease progression on PFT and thoracic imaging at 6, 12 and 24 months since AF prescription. Statistical analyses considered three subgroups, according to CPFE identification and extension (above or below 15%). Survival was evaluated using Cox regression and Kaplan Meier, and adjusted to comorbidities. Results: This cohort encompasses 118 patients, 97 (82.2%) males, 75.8 years on average, 32 (27.1%) with CPFE - 20 (16.9%) above 15% (CPFE>15%). No significant differences in age, gender, smoking habits, comorbidities or PFT parameters at baseline, between IPF and CPFE>15% (except lower DLCO and FEV1/FVC in CPFE>15%); nor regarding death [50.0% vs 70.9%, X2 (1, N=106)=3.21, p=0.073] or lung transplantation [10.0% vs 2.2%, X2 (1, N=36)=0.01, p=0.906]; nor in fibrosis extent or PFT parameters' evolution at 6, 12 or 24 months. CPFE>15% had worse overall survival than IPF, though not significantly (45.3 months, 95%CI [34.3-56.3] vs 56.8 months, 95%CI [45.8-67.8], respectively; log rank 0.01, p=0.929). Conclusions: CPFE patients seemingly have similar responses to AF, compared to IPF. However, their tendency to poorer survival suggests a higher relevance of early treatment and particular care in comorbidities' management.