Late Breaking Abstract - Prognostic value of serum biomarkers in patients with idiopathic pulmonary fibrosis and correlation with disease progression

Purpose: The aim of the present study was to determine serum biomarker levels and their correlation with respiratory function and clinical course of patients with idiopathic pulmonary fibrosis (IPF) followed up in the Out-Patient University clinic. Patients and methods: The study included 55 patients (mean age 72 ± 6 years), 83% men with idiopathic pulmonary fibrosis according to the ATS/ERS criteria, who were under anti-fibrotic treatment. Blood samples were taken and serum biomarkers as KL-6, SP-D, CCL18, CXCL13, VEGF-A, IL-8, IGFBP-1, IGFBP-2, IGFBP-7 and ICAM-1 were measured by ELISA. In addition, pulmonary function tests (FVC, TLC, DLCO-% pred) were determined at 4 time-points (initial value, after 6, 12 and 24 months). Results: KL-6 protein levels were positively correlated with IGFBP-1 and IGFBP-2 levels, IL-8 levels with VEGF-A, IGFBP-7 levels with CXCL13 and CCL18 levels with CXCL13 in all patients (p <0.05). CCL18 levels were found to be significantly higher in men and were positively correlated with TLC values in patients with disease progression. SP-D and VEGF-A levels were found to be significantly higher in patients who either had disease worsening or have deceased (p<0.05). In addition, a negative correlation was found between SP-D levels and the DLCO rate after 12 months (p <0.05). Conclusions: This is one of very few studies evaluating a wide range of biomarkers and correlating them with disease progression in Greek patients with IPF. Our results suggest that SP-D, VEGF-A and CCL18 have a prognostic value in disease progression in IPF.