Multivariate analysis of antibody induction therapy and their associated outcomes in deceased donor transplants

The aims of this study were to describe factors associated with the use of overall induction, classes of induction agents, and to evaluate the incidence of acute rejection, short-term graft survival, and patient survival.

Of 24,901 transplants reported to the United Network for Organ Sharing (UNOS) between 1999 and 2001, 51% received induction therapy including Thymoglobulin (T; n = 3090), Simulect (S; n = 6063), or Zenapax (Z; n = 3755). Propensity scores (PS) were calculated to indicate factors associated with use of induction and for each induction agent. Outcome parameters included graft survival (GS), hazard ratio (HR) for graft loss (GL), and odds ratio (OR) for first-year acute rejection (AR).

Pediatric (PS = 1.29; 95% confidence interval [CI] 1.12-1.49, vs adults) and retransplanted recipients (PS = 1.36; 1.23-1.49, vs first) were more likely to receive induction. One-year GS (90.1 vs 88.0%; P < .001), GL = 0.92% (0.86-0.98; P = .01), and AR free = 0.74 (P < .001) were superior in patients receiving induction. Using multivariate analysis, the odds of rejection 0.73 (0.68-0.78), GL 0.91 (0.85-0.97), and death 0.90 (0.82-0.98) were lower in those receiving induction. Among patients given induction, those receiving T were more likely sensitized (PS = 1.50%; 1.31-1.71), retransplanted (PS = 1.51; 1.31-1.75), or had delayed graft function (PS = 1.75; 1.58-1.93). T decreased the odds of rejection compared with S or Z (OR = 0.74; 0.69-0.79), but the type of induction agent did not have an impact on graft outcome HR for T = 1.07 (0.96-1.19).

The use of antibody induction was associated with lower risk of rejection and better GS. There were no differences in GS among individual regimens. Comparative safety data were not analyzed but should be taken into consideration when choosing antibody preparations.