Association of Discharge Immunosuppression Regimen and Post-Transplant Outcomes in Lung Transplantation: An Analysis of OPTN Data

PURPOSE: The optimal immunosuppressive (IS) regimen after lung (LU) transplant is unknown, therefore we sought to examine OPTN data to compare the impact of 4 different IS combinations on outcomes of treated acute rejection (AR), bronchiolitis obliterans syndrome (BOS), and graft survival. METHODS: We used OPTN data for adult recipients of primary, DD, LU alone transplants during 2005-2015, who were alive at discharge and on one of the following discharge IS regimens: cyclosporine + azathioprine (CYA+AZA), cyclosporine + MMF (CYA+MMF), tacrolimus + azathioprine (TAC+AZA), or TAC+MMF. One-year treated AR was compared by IS regimen using a chi-square test. Freedom from BOS and graft survival within 5 years were estimated using Kaplan-Meier methods and compared by IS regimen using a log-rank test. Cox regression analysis was performed to assess the association of IS regimen and BOS, adjusted for other covariates. RESULTS: Of 14,798 recipients in the study cohort, 10,842 (73%) were on TAC+MMF, 2,968 (20%) on TAC+AZA, 587 (4%) on CYA+AZA, and 401 (3%) were on CYA+MMF. One-year rates of treated AR were significantly different across IS regimens (56% for CYA+AZA, 36% for CYA+MMF, 32% for TAC+AZA, and 27% for TAC+MMF) (p<0.0001). Unadjusted freedom from BOS and graft survival were significantly different across IS regimens (Figures 1 and 2). The results of the adjusted Cox regression model showed that the TAC+MMF regimen was associated with a significantly decreased risk of BOS within 5 years compared to the other 3 regimens. CONCLUSION: In this non-randomized OPTN registry analysis, TAC+MMF was associated with a lower rate of unadjusted one-year treated AR and reduced, adjusted risk of BOS within 5 years compared to the other regimens. Unadjusted graft survival was higher for TAC-based regimens compared to CYA-based regimens. Limitations of this analysis included the small numbers of patients in some of the IS groups, and not accounting for changes in the IS regimen post-discharge.

Duke Scholars

Author Scott Michael Palmer Jr. Medicine, Pulmonary, Allergy, and Critical Care Medicine