Kidney transplant outcomes in children with simultaneous versus sequential heart-kidney transplants.

ABSTRACT

BACKGROUND: Heart transplant recipients frequently require kidney transplantation for concomitant advanced chronic kidney disease. Data on simultaneous (heart and kidney transplants performed simultaneously) versus sequential (heart transplant performed before kidney) heart-kidney transplants in children are limited. Herein, we compare kidney transplant outcomes between the two groups. METHOD: We used the Scientific Registry of Transplant Recipients to identify all pediatric (age <21 years) heart transplant recipients who also received a kidney transplant within 10 years of the heart transplant. We divided the study cohort into simultaneous heart-kidney and sequential heart-kidney recipients. We compared patient and death-censored graft survival using the Cox regression, adjusting for age at kidney transplant, sex, race, pre-transplant dialysis, donor type, and prior kidney transplant. We evaluated delayed graft function (defined as dialysis within the first week posttransplant) using logistic regression. RESULTS: Our analysis cohort included 165 recipients (86 simultaneous and 79 sequential). The incidence of delayed graft function was higher in simultaneous recipients (22.4 vs. 7.7%, p=0.017), but the difference lost statistical significance on multivariable analysis. We found no difference in patient survival (aHR 0.97; 95% CI 0.39, 2.41; p=0.95) after kidney transplant but higher death-censored kidney graft survival in sequential heart-kidney recipients compared with simultaneous heart-kidney recipients (aHR 4.26; 95% CI 1.21, 14.9; p=0.02). CONCLUSION: Sequential heart-kidney transplants are associated with higher death-censored kidney allograft survival in children compared with simultaneous heart-kidney transplants.