Pulmonary Function in Idiopathic Pulmonary Fibrosis and Referral for Lung Transplantation

Of patients awaiting lung transplantation, the death rates are highest in those with idiopathic pulmonary fibrosis (IPF), suggesting that many IPF patients are referred late for transplantation. Therefore this study was undertaken to evaluate baseline pulmonary function test (PFT) and high-resolution computed tomography (HRCT) fibrosis scores, and the relationship to survival in IPF patients younger than 65 yr of age. A total of 115 patients with usual interstitial pneumonia (UIP) were studied. At presentation to a tertiary referral center, PFT and HRCT data were collected and analyzed for prognostic significance: the primary outcome measure was patient death. Based on the length of the waiting list for transplantation, prediction of 2-yr survival was examined. DL(CO) percent predicted and HRCT-fibrosis score were found to be independent predictors of survival and in combination gave the best prognostic prediction. The optimal points on the receiver operating characteristic (ROC) curves for discriminating between survivors and nonsurvivors corresponded to 39% DL(CO) percent predicted, and to a HRCT-fibrosis score of 2.25. The combination of these parameters yielded an optimal point with a specificity and a sensitivity of 84% and 82%, respectively. A model based on a combination of DL(CO) percent predicted and HRCT-fibrosis score may optimize the timing of referral for transplantation.