Progressive fibrosing interstitial lung disease: a clinical cohort (the PROGRESS study)

In patients with chronic fibrosing interstitial lung disease (ILD), a progressive fibrosing phenotype (PF-ILD) may develop, but information on the frequency and characteristics of this population outside clinical trials is lacking. We assessed the characteristics and outcomes of patients with PF-ILD other than idiopathic pulmonary fibrosis (IPF) in a real-world, single-centre clinical cohort. The files of all consecutive adult patients with fibrosing ILD (2010-2017) were examined retrospectively for pre-defined criteria of >= 10% fibrosis on high-resolution computed tomography and progressive disease during overlapping windows of 2 years. Baseline was defined as the date disease progression was identified. Patients receiving nintedanib or pirfenidone were censored from survival and progression analyses. In total, 1395 patients were screened; 617 had ILD other than IPF or combined pulmonary fibrosis and emphysema, and 168 had progressive fibrosing phenotypes. In 165 evaluable patients, median age was 61 years; 57% were female. Baseline mean forced vital capacity (FVC) was 74 +/- 22% predicted. Median duration of follow-up was 46.2 months. Annualised FVC decline during the first year was estimated at 136 +/- 328 ml using a linear mixed model. Overall survival was 83% at 3 years and 72% at 5 years. Using multivariate Cox regression analysis, mortality was significantly associated with relative PVC decline >= 10% in the previous 24 months (p<0.05), age >= 50 years (p<0.01) and diagnosis subgroup (p<0.01). In this cohort of patients with PF-ILD not receiving antifibrotic therapy, the disease followed a course characterised by continued decline in lung function, which predicted mortality.

Automated summary

This study examined the characteristics and outcomes of patients with progressive fibrosing phenotypes other than idiopathic pulmonary fibrosis (IPF) in a real-world setting. Among patients with PF-ILD not receiving antifibrotic therapy, the disease followed a course characterized by continued decline in lung function, which predicted mortality.