Insights from the UNOS Database on the Impact of Laterality on Outcomes in Lung Transplantation: Left is Not Always Right in Single Lung Transplantation

Abstract

Lung transplantation remains an established therapy for end stage lung disease. It is well known that double lung transplant recipients have a survival advantage over single lung transplant (SLTxp) recipients. There is a gap in knowledge regarding how laterality might affect survival in these recipients. We hypothesized that recipients who need a single left lung transplant might have shorter wait times and improved survival compared to right. This is a retrospective analysis of de-identified data from the UNOS registry. SLTxp adult recipients who were transplanted for COPD and IPF diagnoses were queried from January 2006 to September 2018. Group comparisons were made with chi-square for categorical and student's t-test for continuous variables. The univariate odds ratios, obtained using logistical regression, was adjusted for the presence of confounders. Survival using Kaplan-Meier survival curve was examined. The final study cohort consisted of 6,730 recipients who received a SLT for COPD or IPF. Total number of SLT during this period included: IPF right (n=2054) vs left (n=2568) and COPD right (n=1029) vs left (n=1079) respectively. Median time from transplant to follow-up was 23.5 months. The difference in the wait list times in both cohorts, COPD and IPF was statistically significant between right and left lung recipients (IPF: Left 99.6 vs Right: 96.7 days; COPD: Left: 226 vs Right 233 days). In the IPF lung transplant recipients no difference in survival was observed between right vs left lung transplantation. (Figure A) In the COPD cohort, right lung recipients had a better post-transplant survival (Figure B). The wait time for both cohorts, COPD and IPF was longer for right vs left lung recipients. Compared to left lung recipients, Right LT recipients for COPD reported better survival but this difference in survival was not seen in the IPF cohort. The reason for this survival advantage needs to be studied further.