Elastokines are Associated with a Poor Prognosis in Idiopathic Pulmonary Fibrosis.

Background: During the development of idiopathic pulmonary fibrosis (IPF), elastin is broken down and replaced with a stiffer substrate which interferes with normal breathing. This remodeling releases elastin degradation products (EDPs), or elastokines, which can then be measured. We examined the association between elastokine concentrations and disease severity to determine if EDP concentrations are associated with clinically relevant markers in IPF. Methods: Concentrations of elastokines were measured via enzyme linked immunosorbent assay (ELISA). Samples were obtained from a single institution's Interstitial Lung Disease (ILD) registry/biorepository (n = 81 with IPF and 24 healthy volunteers). We used linear and logistic regression modeling to assess the association between EDP concentrations at the time of diagnosis, lung function, and clinical outcomes. Results: Patients with IPF were older, more likely to be male, had ever smoked, and had worse lung function compared to healthy volunteers (p value ≤ 0.02 for all parameters). Patients with IPF had higher concentrations of elasotkines (p < 0.001), and the highest elastokine concentrations were associated with reduced forced vital capacity (FVC, p = 0.026), and decreased three-year transplant-free survival (p = 0.0005). These findings suggest that elastokines are biomarkers of matrix turnover and are associated with relevant clinical outcomes in patients with IPF.