Second Kidney Transplant Outcomes in Dialysis Dependent Recipients by Induction Type in the United States

Background: We examined the association between induction type for a second kidney transplant in dialysis-dependent recipients and the long-term outcomes. Methods: Using the Scientific Registry of Transplant Recipients, we identified all second kidney transplant recipients who returned to dialysis before re-transplantation. Exclusion criteria included: missing, unusual, or no-induction regimens, maintenance regimens other than tacrolimus and mycophenolate, and positive crossmatch status. We grouped recipients by induction type into 3 groups: the anti-thymocyte group (N = 9899), the alemtuzumab group (N = 1982), and the interleukin 2 receptor antagonist group (N = 1904). We analyzed recipient and death-censored graft survival (DCGS) using the Kaplan-Meier survival function with follow-up censored at 10 years post-transplant. We used Cox proportional hazard models to examine the association between induction and the outcomes of interest. To account for the center-specific effect, we included the center as a random effect. We adjusted the models for the pertinent recipient and organ variables. Results: In the Kaplan-Meier analyses, induction type did not alter recipient survival (log-rank P = .419) or DCGS (log-rank P = .146). Similarly, in the adjusted models, induction type was not a predictor of recipient or graft survival. Live-donor kidneys were associated with better recipient survival (HR 0.73, 95% CI [0.65, 0.83], P < .001) and graft survival (HR 0.72, 95% CI [0.64, 0.82], P < .001). Publicly insured recipients had worse recipient and allograft outcomes. Conclusion: In this large cohort of average immunologic-risk dialysis-dependent second kidney transplant recipients, who were discharged on tacrolimus and mycophenolate maintenance, induction type did not influence the long-term outcomes of recipient or graft survival. Live-donor kidneys improved recipient and graft survival.