Early steroid withdrawal and kidney transplant outcomes in first-transplant and retransplant recipients

Background. Early steroid withdrawal (ESW) is often preferred over conventional steroid maintenance (CSM) therapy for kidney transplant recipients with low immunological risks because it may minimize immunosuppression-related adverse events while achieving similar transplant outcomes. However, the risk-benefit balance of ESW could be less favorable in retransplant recipients given their unique immunological risk profile. We hypothesized that the association of ESW with transplant outcomes would differ between first-transplant and retransplant recipients. Methods. To assess whether the impact of ESW differs between first and retransplant recipients, we studied 210 086 adult deceased-donor kidney transplant recipients using the Scientific Registry of Transplant Recipients. Recipients who discontinued maintenance steroids before discharge from transplant admission were classified with ESW; all others were classified with CSM. We quantified the association of ESW (vs CSM) with acute rejection, death-censored graft failure and death, addressing retransplant as an effect modifier, using logistic/Cox regression with inverse probability weights to control for confounders. Results. In our cohort, 26 248 (12%) were retransplant recipients. ESW was used in 30% of first-transplant and 20% of retransplant recipients. Among first-transplant recipients, ESW was associated with no significant difference in acute rejection {adjusted odds ratio (aOR) = 1.04 [95% confidence interval (CI) = 1.00-1.09]}, slightly higher hazard of graft failure [hazard ratio (HR) = 1.09 (95% CI = 1.05-1.12)] and slightly lower mortality [HR = 0.93 (95% CI = 0.91-0.95)] compared with CSM. Nonetheless, among retransplant recipients, ESW was associated with notably higher risk of acute rejection [OR = 1.42 (95% CI = 1.29-1.57); interaction P < .001] and graft failure [HR = 1.24 (95% CI = 1.14-1.34); interaction P = .003], and similar mortality [HR = 1.01 (95% CI = 0.94-1.08); interaction P = .04]. Conclusions. In retransplant recipients, the negative impacts of ESW on transplant outcomes appear to be non-negligible. A more conservatively tailored approach to ESW might be necessary for retransplant recipients.