Early Corticosteroid Withdrawal Under Modern Immunosuppression in Renal Transplantation: Multivariate Analysis of Risk Factors for Acute Rejection

Abstract

Early corticosteroid withdrawal has been shown to be effective in low-risk patient populations in a number of US and European multicenter trials. However, patient populations traditionally considered to be at high risk for acute rejection (eg, African Americans, repeat transplant recipients, sensitized patients) are usually excluded from these trials. Since our initial experience with early withdrawal almost 10 years ago, we have included high-immunologic-risk patients. We have accumulated enough high-risk patients with early withdrawal to allow the first multivariate analysis of risk factors for acute rejection in early withdrawal under modern immunosuppression. Methods Early withdrawal was performed under prospective IRB-approved protocols. Statistical analysis included chi square test and logistic regression. All rejection episodes were biopsy proven and graded by Banff 1997 criteria. Results A total of 164 patients underwent early withdrawal: 82% had at least one mismatched DR antigen, 17% had delayed graft function, 33% were African American, and 18% were repeat transplant recipients. Multivariate analysis of risk factors for acute rejection indicated that two factors induced a statistically significant alteration in acute rejection risk: repeat transplant recipients (4.3-fold increased risk) and thymoglobulin induction (0.30 risk (ie, 70% reduction in risk compared to patients not receiving thymoglobulin induction). Sensitized recipients and African Americans were also at increased risk but did not quite reach statistical significance. These data strongly support the use of T-cell depleting antibody induction therapy in high-risk patients undergoing early withdrawal under modern immunosuppression.