Prognostic factors of progressive fibrotic hypersensitivity pneumonitis: a large, retrospective, multicentre, observational cohort study

• Published in: ERJ open research Vol. 10; no. 1; p. 405
• Main Authors: Cano-Jiménez, Esteban, Villar Gómez, Ana, Velez Segovia, Eduardo, Aburto Barrenechea, Myriam, Sellarés Torres, Jacobo, Francesqui, Joel, Portillo Carroz, Karina, Solis Solis, Alan Jhunior, Acosta Fernández, Orlando, Llanos González, Ana Belén, Bordas-Martinez, Jaume, Cabrera Cesar, Eva, Balcells Vilarnau, Eva, Castillo Villegas, Diego, Reyes Pardessus, Ana, González Fernández, Coral, García Moyano, Marta, Urrutia Gajate, Amaia, Blanco Hortas, Andrés, Molina-Molina, María
• Format: Journal Article
• Language: English
• Published: England European Respiratory Society 01.01.2024
• Subjects: Original s
• ISSN: 2312-0541; 2312-0541
• DOI: 10.1183/23120541.00405-2023

Fibrotic hypersensitivity pneumonitis (fHP) is an immune-mediated interstitial lung disease caused by sensitisation to chronic allergen inhalation. This study aimed to determine prognostic indicators of progression and mortality in fHP. This was a retrospective, multicentre, observational, cross-sectional cohort study of consecutive patients diagnosed with fHP from 1 January 2012 to 31 December 2021. Multivariate Cox regression analyses were used to calculate hazard ratios (HRs) with 95% confidence intervals for predictors of progression and survival. A total of 403 patients were diagnosed with fHP: median (interquartile range) age 66.5 (14.0) years, 51.9% females and 55.1% never-smokers. The cause of fHP was mainly fungal (39.7%) or avian (41.4%). Lung biopsy was performed in 269 cases (66.7%). In the whole cohort the variables that were related to mortality or lung transplant were older age (HR 1.08; p<0.001), percentage predicted forced vital capacity (HR 0.96; p=0.001), lymphocytosis in bronchoalveolar lavage (BAL) (HR 0.93; p=0.001), presence of acute exacerbation during follow-up (HR 3.04; p=0.001) and GAP (gender, age and lung physiology) index (HR 1.96; p<0.01). In the group of biopsied patients, the presence of fibroblastic foci at biopsy (HR 8.39; p<0.001) stands out in multivariate Cox regression analyses as a highly significant predictor for increased mortality or lung transplant. GAP index (HR 1.26; p=0.009), lymphocytosis in BAL (HR 0.97; p=0.018) and age (HR 1.03; p=0.018) are also predictors of progression. The study identified several prognostic factors for progression and/or survival in fHP. The presence of fibroblastic foci at biopsy was a consistent predictor for increased mortality and the presence of lymphocytosis in BAL was inversely related to mortality.