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.