Abstract 10807: Thymoglobulin Induction may Confer Survival Benefit in Younger African-American Patients: Review of the United Network for Organ Sharing Database
Purpose: Disparity in heart transplant outcomes between African Americans and Caucasian American patients is known. These differences may due to genetic differences in the metabolism of immunosuppressant. The role of induction therapy in the African American population has not been established. We evaluated whether use of thymoglobulin induction improved outcomes in African Americans using the United Network for Organ Sharing (UNOS) database.
Methods: 11,521 consecutive adult patients (2065 African Americans and 9456 Caucasian Americans) from the UNOS database transplanted between 1/2000 and 3/2011 were included. Data were further analyzed using three age groups; Group 1 age 21-39, Group 2 age 40-59 and Group 3 age 60. 5-year survival was estimated by Kaplan-Meier method. Survival was compared across groups by Log-Rank and Wilcoxon tests. Cox proportion hazards models were used to obtain hazard ratios and 95% confidence intervals.
Results: For all ages, African Americans vs Caucasian Americans (with/without thymoglobulin induction) had significantly lower 5-year actuarial survival (Log-Rank p < 0.0001) (figure). For African Americans alone, thymoglobulin induction vs none showed a trend for survival benefit (HR 0.84 with 95%CI = 0.68-1.04, p = 0.062). Comparing thymoglobulin induction by age in African Americans shows significant survival benefit for the younger Group 1 but a trend towards worsening survival in the older group 3 (Group 1 HR=0.67 with 95% CI = 0.68-1.04; p = 0.034. Group 2 HR 0.81 with 95% CI = 0.60-1.08, p = 0.065. Group 3 HR = 1.35 with 95% CI = 0.89-2.04, p = 0.101).
Conclusion: African American patients have worse overall 5-year survival after heart transplant compared to Caucasian Americans with or without thymoglobulin induction. Thymoglobulin may however confer protection in the young African American patients. Randomized trials to assess efficacy of induction therapy are indicated.
- © 2012 by American Heart Association, Inc.