Multi-Dimensional Assessment in Idiopathic Pulmonary Fibrosis

Abstract

SESSION TITLE: Diffuse Lung Disease 1 SESSION TYPE: Original Investigation Poster PRESENTED ON: Wednesday, November 1, 2017 at 01:30 PM - 02:30 PM PURPOSE: Purpose. The clinical course of idiopathic pulmonary fibrosis (IPF) is difficult to predict. Perceived dyspnea, exercise capacity, and lung physiology have all been associated with mortality outcomes in IPF, but the significance of this relationship is unclear. We sought to investigate the strength of the relationship between these variables and their independent predictive capability in determining mortality outcomes. METHODS: Methods. Four-hundred-thirty-seven patients from 3 different centers (Western University, University of Toronto, University of Rome) with IPF were included in the study. Medical Research Council dyspnea score (MRCDS), 6-minute walk distance percent predicted (6MWD %pred) and pulmonary function tests, including calculation of the composite physiologic index (CPI), were determined at baseline. The endpoint was 18-month mortality/lung transplant (LTx). RESULTS: Results. Correlations between MRCDS, 6MWD % pred, forced vital capacity (FVC) and diffusing lung capacity for carbon monoxide (DLCO) were weak (r<0.5). Collinearity between variables, measured by variance inflation factors, was low. At the end of the observation period, 165 patients were alive, 167 had been transplanted, and 105 had died. Univariate regression analysis and c-statistics identified MRCDS (H.R=1.89, AUC=0.74), 6MWD % pred (H.R.=0.97, AUC=0.79), FVC (H.R.=0.97, AUC=0.76), and CPI (H.R.=1.05, AUC=0.78) as significant predictors of 18-month mortality/LTx. Multivariate regression analysis retained MRCDS (H.R.=1.33), 6MWD % pred (H.R.=0.982) and FVC %pred (H.R.=0.99) or MRCDS (H.R.=1.33), 6MWD % pred (H.R.=0.98), and CPI (H.R.=1.02) as independent predictors of outcome. CONCLUSIONS: Conclusion. Baseline dyspnea, exercise capacity and physiology are weakly correlated to each other, translating in low collinearity among variables. MRCDS, 6MWD % pred and CPI (or FVC) are significant, independent predictors of outcome. CLINICAL IMPLICATIONS: Clinical Implications. MRCDS, 6MWD%pred and CPI (or FVC) provide independent prognostic information, suggesting that a multi-dimensional assessment of mortality in patients with IPF is feasible and advantageous. DISCLOSURE: The following authors have nothing to disclose: Hana Serajeddini, Marco Mura, Paola Rogliani No Product/Research Disclosure Information