Survival After Single Versus Bilateral Lung Transplantation for High-Risk Patients With Pulmonary Fibrosis

Background: Whether single lung transplantation (SLT) or bilateral lung transplantation (BLT) is optimal for patients with severe idiopathic pulmonary fibrosis (IPF) is unknown. We examine a large multi-institutional cohort of high-risk IPF patients to address this question. Methods: We retrospectively reviewed United Network for Organ Sharing data to identify 1,256 lung transplant (LTx) recipients with IPF between 2005 and 2007. Risk of 30-day, 90-day, and 1-year mortality for SLT versus BLT was examined across levels of the lung allocation score (LAS [both continuous with incorporation of interaction terms and categorized by LAS quartiles]). Multivariable analysis was conducted through Cox proportional hazards regression. Results: Lung allocation score quartiles were as follows: quartile 1, 29.8 to 37.8, n = 315; quartile 2, 37.9 to 42.4, n = 313; quartile 3, 42.5 to 51.9, n = 314; and quartile 4, 52.0 to 94.1, n = 314. Overall, 21.1% more patients received BLT in the highest LAS quartile (59.5%) than in the lowest LAS quartile (38.4%, p < 0.05). In patients at highest risk, BLT was associated with a 14.4% decrease in mortality at 1 year after LTx. This survival benefit was confirmed on univariate analysis (hazard ratio 1.90 [95% confidence interval: 1.16 to 3.13], p = 0.01) and multivariable analysis (hazard ratio 2.09 [95% confidence interval: 1.07 to 4.10], p = 0.03) as well as in sensitivity analyses incorporating pulmonary hypertension and maximizing follow-up. There were no differences in the risk of death with SLT at 30 or 90 days after LTx in any quartile on unadjusted or multivariable adjusted analysis. Conclusions: We provide an initial examination of survival by procedure type and LAS score for LTx recipients with IPF. Bilateral LTx appears to offer advantages over SLT for high-risk patients.