Background: Age has been implicated as a factor in the plateau of long-term survival after lung transplant.
Methods: We used data from the Scientific Registry of Transplant Recipients to identify all recipients of lung transplant aged ≥18 years of age between January 1, 2006, and February 19, 2015. A total of 14,253 patients were included in the analysis. Survival was estimated using a nonproportional hazard model and random-survival forest methodology was used to examine risk factors for death. Final selection of model variables was performed using bootstrap aggregation. Age was analyzed as both a continuous and categorical variable (age <30, 30-55, and >55 years). Risk factors for death were obtained for the entire cohort and additional age-specific risk factors were identified for each age category.
Results: The median age at transplant was 59 years. There were 1,098 (7.7%) recipients <30 years, 4,201 (29.5%) 30 to 55 years, and 8,954 (62.8%) >55 years of age. Age was the most significant risk factor for death at all time-points following transplant and its impact becomes more prominent as time from transplant increases. Risk factors for death for all patients included extremes of age, higher creatinine, single lung transplant, hospitalization before transplant, and increased bilirubin. Risk factors for death differed by age with social determinants of health disproportionately affecting survival for those in the youngest age category.
Conclusions: The youngest and oldest adult recipients experienced the lowest posttransplant survival through divergent pathways that may present opportunities for intervention to improve survival after lung transplant.
Keywords: lung transplant; lung transplant outcomes; organ allocation; random survival forest.
Copyright © 2019 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.