Outcomes of Single vs. Double Lung Retransplantation in Patients with Cystic Fibrosis.

OBJECTIVE Patients requiring lung transplant for cystic fibrosis (CF) may require retransplant due to limited graft survival and otherwise excellent life expectancy. Optimal transplant strategy for this population, including single vs. double lung retransplant, has not been established. METHODS We performed a retrospective analysis of the UNOS/OPTN database to identify adult lung retransplant recipients from 2005-2021 with a primary diagnosis of CF. Patients were stratified by retransplant type (single lung [re-SLTx] vs. double lung [re-DLTx] retransplant). Descriptive statistics, Kaplan-Meier survival analysis, and multivariable Cox regression were performed. RESULTS From 2005-2021, 384 recipients underwent retransplant after an initial transplant for an indication of CF; more recipients underwent re-DLTx (N=337 [87.8%]) than re-SLTx (N=47 [12.2%]). The median (IQR) time from initial transplant to retransplant was similar between re-SLTx and re-DLTx recipients (4.4 [2.9-8.6] vs. 4.6 [2.6-7.4] years, p=0.73). Ischemic time was shorter and lung allocation score was lower for re-SLTx than re-DLTx recipients. Median survival after retransplant was significantly shorter for re-SLTx vs. re-DLTx recipients (2.0 [95% CI 1.2-3.5] vs. 4.3 [95% CI 3.5-6.1] years post-retransplant, p=0.008). Median survival for adults with CF undergoing primary transplant for CF in the same period was 9.1 (8.5-9.9) years. After adjusting for donor and recipient characteristics, re-SLTx in patients with CF was associated with 88% higher hazard of mortality than re-DLTx (aHR=1.88 [95% CI 1.28-2.78], p=0.001). CONCLUSIONS In this analysis of lung retransplant in recipients with CF, re-SLTx was associated with a higher hazard of mortality compared to re-DLTx, supporting re-DLTx as treatment for this population.