Background: KL-6 and surfactant proteins A and D are the only established serum biomarkers of idiopathic pulmonary fibrosis (IPF). We have previously shown that serum levels of periostin, a unique matricellular protein, are elevated and correlated with pulmonary function in patients with IPF. We sought to determine whether the serum periostin levels correlate with overall survival (OS) and time-to-event (TTE), as a parameter reflecting long-term outcome, and with the extent of abnormality on chest high-resolution computed tomography (HRCT) scores in patients with IPF.
Methods: Twenty-nine patients with IPF were analyzed retrospectively. The mean observation period was 1035.2 ± 663.1 days (range, 112-1800 days). High-resolution computed tomography (HRCT) scores were calculated based on the extent of abnormality evidenced by HRCT. We evaluated if there were any correlations between the serum periostin levels and clinical parameters, including HRCT score, using Spearman's rank correlation coefficients and analyzed predictors of OS and TTE using the log-rank tests.
Results: We showed that the serum periostin levels significantly correlated with the increase of honeycombing score on HRCT during a 6-month period. Log-rank tests showed that a higher serum periostin level was a predictor of a shortened OS and TTE. Greater extents of fibrotic lesions on HRCT scan were predictors of shortened OS and TTE.
Conclusions: In IPF patients, the serum periostin level may be a good predictive biomarker for an increase in the radiological fibrotic area and long-term outcome.
Keywords: Biomarker; High-resolution computed tomography; Idiopathic pulmonary fibrosis; Periostin.
Copyright © 2014 The Japanese Respiratory Society. Published by Elsevier B.V. All rights reserved.