Epidemiology, Risk Factors, and Outcomes of Lung Retransplantation: An Analysis of the International Society for Heart and Lung Transplantation (ISHLT) Registry

Abstract

To compare the relative importance of several clinical, donor, and recipient factors on the risk for mortality following lung retransplantation (LRTx). First-time adult recipients of deceased-donor LRTx between 5/2005 and 6/2017 reported to the ISHLT Registry were included in our analysis. Important risk factors for 1-yr mortality following LRTx were examined using the Somers' rank correlation statistic (Dxy) for censored data and included: inter-transplant interval, initial and retransplant procedure, indication of obliterans bronchiolitis, recipient retransplant factors (age, gender, diabetes, ECMO use, mechanical ventilation use, FVC, and FEV1), CMV serostatus match, and donor variables (cause of death, age, human leukocyte antigen (HLA) mismatch level, and ischemic time). 1597 LRTx recipients were included; since 2007, 138-188 retransplants (4-6% of all transplants) were reported annually to the Registry. The median inter-transplant interval was 1243 days (IQR: 573 to 2256). Most LRTx recipients had IPF (88%), 32% were retransplanted within 2 yrs, and 64% received bilateral transplant both times, whereas 36% received consecutive single transplants. The 3-mo, 6-mo, and 1-yr survival rates were 86%, 82%, and 76% for bilateral-bilateral recipients, and 82%, 76%, and 69% for single-single recipients (p=0.001). The 3 strongest risk factors for 1-yr mortality, as indicated by the 3 highest Somers' rank (and highest C-index) correlation statistics (i.e., Dxy absolute values in the figure) were the inter-transplant interval (decreasing hazard with longer intervals), donor age, and need for mechanical ventilation at LRTx. The strongest predictor of 1-yr mortality is the duration of time since the initial transplant, with a persistent reduction in risk as more time elapses between the initial transplant and LRTx.