End Stage Idiopathic Pulmonary Fibrosis: Which Patients Are at Higher Risk of Mortality Awaiting Lung Transplantation?

Purpose: To date factors predicting a fatal outcome in patients with end stage idiopathic pulmonary fibrosis (IPF) awaiting lung transplantation (LTx) are not well established yet. Aim: to better characterize the higher risk population among IPF patients listed for LTx, we investigated constitutional and cardiopulmonary parameters, their mutual relationship and their potential impact on mortality. Methods and Materials: From 2000 to 2007, 56 patients with end stage IPF were included on waiting list for LTx. Right-heart atheterization and pulmonary function test were performed. Results: 37 patients received LTx, 11 died on waiting list and 8 are still alive awaiting LTx. Pulmonary arterial hypertension (PAH) was present in 25 out of 56 patients (44.6%). The 11 patients who died had mPAP significantly higher than others (28.55.7 vs 22.28.20 mmHg; p0.01), while DLCO and PaO2 were lower (DLCO %pred 14.97.4 vs 25.312.3, p0.01; PaO2 49.210.3 vs 57.312.3mmHg, p0.03). Survivors in waiting list had BMI significantly higher than deceased (303,2 vs 26,14,3; p0.03). A linear inverse correlation was observed between mPAP and DLCO %pred (p0.01, r0.34); mPAP and mean walking distance (p0.01, r-0.32). Crude one-year mortality rate on waiting list was higher for PAH patients than non PAH patients (42% and 6%, respectively; RR 7.06–95%CI: 1.46-67.14). On multivariate analysis PAH (OR: 10.55 – 95%CI:1.53-72.63; p0.02) and PaO2 on room air (OR:7.27 – 95%CI:1.03-51.21; p0.05) were independent predictors of mortality. Conclusions: PAH is a common feature in end stage IPF and is associated with an higher risk of mortality on waiting list. mPAP is inversely correlated with DLCO and 6MWT. Higher BMI is associated with a decreased mortality.