ORLANDO – Age and increased lung allocation score are among factors associated with risk of lung retransplantation, according to an analysis of data from the United Network for Organ Sharing.
Of 24,194 consecutive patients who underwent lung transplantation between 1987 and 2012 and who were included in the nationwide registry, 941 (3.9%) underwent retransplantation. Age over 40 years, increased lung allocation score, increased percentage decline in forced ventilatory capacity (FVC), and readmission to the intensive care unit each were associated with retransplantation (odds ratios, 2.26, 0.98, 0.99, and 2.27, respectively), Dr. J. Awori Hayanga reported at the annual meeting of the Society of Thoracic Surgeons.
The current findings could allow for better prediction of graft failure and the need for retransplantation, and could help guide immunosuppression protocols and donor selection, he said. This is important, because although the overall volume of retransplantation remains less than 5%, the number of such procedures is steadily increasing, with up to 100 now performed each year.
Dr. J. Awori Hayanga
"Following the introduction of the lung allocation score, the waiting time decreased, and the volume, perhaps predictably, increased by almost 60% with this increased emphasis on clinical acuity. The relative paucity of donors nevertheless engenders a considerable amount of scrutiny," Dr. Hayanga said. "Contention exists between the utilitarian view, where allocation prioritizes recipients in most need, versus the egalitarian view that seeks to provide equal opportunity to all those in need," he explained.
While this ethical argument is "tempered somewhat by steadily improving outcomes," retransplantations still remain inferior to primary transplantations, carrying a 30% overall increased risk of death. Prior to this study, the risk factors for retransplantation were poorly characterized in the literature.
The study also showed that donor factors associated with retransplantation included smoking history and body mass index less than 18.5 kg/m2 (OR, 1.47 and 1.68, respectively). One transplant-related factor – increased graft ischemic time – was also associated with retransplantation (OR, 0.91), said Dr. Hayanga of the University of Pittsburgh.
Lung transplantation is a well-established therapeutic option for end-stage lung disease, but long-term outcomes are largely determined by chronic allograft failure – a diagnosis which constitutes "the most justifiable, evidence-driven indication for retransplantation," he said. Survival among patients who undergo retransplantation for this indication have nearly equivalent survival to those with a first transplant, he noted.
Conversely, "there are multiple observations in the literature of the dismal outcomes observed following retransplantation for primary graft failure and airway complications," he noted.
"We seek now to build and validate a risk scoring model to help predict the risk for chronic graft failures and for retransplantation, to enrich the dialogue, to improve immunosuppressive and selection protocols, and ultimately to provide evidence-based prognostic data," he said.
This study was funded by the Ruben J. Williams Foundation. Dr. Hayanga reported having no other disclosures.