Diagnostic and prognostic role of biomarkers for pulmonary hypertension in interstitial lung disease

Background: Pulmonary hypertension (PH) is an important complication to interstitial lung disease (ILD). The aim of the present study was to investigate the relation of NT-proBNP, fibrin D-dimer, troponin-T, uric acid and exhaled nitric oxide (NO) to the presence of PH and mortality in ILD. Methods: In a previously described cohort of 212 ILD patients of whom 29 had PH, levels of the above mentioned biomarkers were analyzed as routine tests. Results: A value of NT-proBNP below 95 ng/l had a negative predictive value for PH of 99% (95% Cl: 94-100). Values of troponin-T were higher in patients with PH (median (inter quartile range) = 9 (9-20) vs. 9(9-10) ng/l), and the odds ratio (OR) for PH was increased in patients with abnormal levels of uric acid (OR (95% Cl) = 3.1(1.1-8.8)). NT-proBNP and troponin-T values above the 50th percentile, and uric acid and fibrin D-dimer values above the 90th percentile were each associated with increased mortality. Conclusions: A value of NT-proBNP below 95 ng/l may be used as a rule-out test for PH in ILD, while an abnormal value of uric acid is a risk factor for PH. NT-proBNP, troponin-T, uric acid and fibrin D-dimer have prognostic value in ILD patients, while exhaled levels of NO do not seem to predict PH or mortality. (C) 2012 Elsevier Ltd. All rights reserved.