B41-08 Characteristics and Management of Patients With Fibrosing Interstitial Lung Disease in Spain: Data From the Separ- ILD Registry

Introduction Fibrotic interstitial lung diseases (fILD) pose a challenge in clinical practice. Idiopathic pulmonary fibrosis (IPF) is the prototype of progressive fibrotic ILD, and it is estimated that up to one-third of people with fibrotic ILDs other than IPF may develop a progressive course like IPF, called progressive pulmonary fibrosis (PPF). The SEPAR-ILD Registry, from the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR), aims to provide real-world data from Spanish patients with fibrosing interstitial lung diseases to better understand the clinical characteristics progression, and management. Methods SEPAR-ILD Registry is an ongoing prospective registry for patients diagnosed with IPF and other fILD since 2022 (Approval December 11, 2023, CEIm minutes 22/23) conducted at 19 expert sites across Spain. Results 481 patients were included. The most frequent diagnoses were IPF 158(32%), Unclassifiable ILD (UILD) (including IPAF) 83 (17,3 %), combined pulmonary fibrosis and emphysema (CPFE) 73(15,2%), connective tissue disease (CTD) ILDs (13.9%), and fibrotic hypersensitivity pneumonitis(fHP) 46(9.6%). The mean (SD) age was 69 (10.6) years; 64.7 % were male, 74.8% former smokers, and 25.2% never smokers. FVC was 83.6 (18.6) % predicted, and diffusion capacity for carbon monoxide (DLCO) was 55.5 (18.3) % predicted. 200 patients (41.7%) were receiving nintedanib and 108 (22.5%) pirfenidone. 132 patients (32.9 %) were on long term oxygen therapy (LTOT)at rest and 138 (34.3 %) during exercise. Comorbidities included high blood pressure 205 (42.7 %), high cholesterol 202(42.1%), diabetes 107 (22,3 %) and ischemic cardiomyopathy 54 (11.3 %). From 336 patients with a median follow up of 12 months disease progression occurred in 151 patients (44.9%) ( In 38 (42%) of patients with IPF, 26 (40%) of CPFE, in 25 (39%) of uILD, 23 (48%) of CTD-ILD and in 12 (44%) of fHP.) presenting worsening of respiratory symptoms 119 (79.3%); worsening of pulmonary function tests 112 (74.7%) and radiological worsening 105 (70.0%). Patients who experienced disease progression exhibited a more severe disease profile, with mean (SD) FVC 77.6 (17.4%) % predicted; DLCO 52.3 (17.8%) % predicted; greater use of LTOT 52.7% of cases; high frequency of hospitalizations (95 [62.9%]), acute exacerbation (32 [22.9%]), and high mortality (37 [40.7%]). Furthermore, they received more frequently nintedanib as antifibrotic therapy (120 [79.5%]). Conclusions Patients with fibrosing ILD in the prospective SEPAR ILD registry had a high rate of disease progression, which is associated with greater severity and a poor outcome.