Association of Recipient APOL1 Kidney Risk Alleles With Kidney Transplant Outcomes

Abstract

Background. Kidney transplant survival in African American recipients is lower compared with non–African American transplant recipients. APOL1 risk alleles (RA) have been postulated as likely contributors. We examined the graft outcomes in kidney transplant recipients (KTRs) stratified by APOL1 RA status in a multicenter observational prospective study. Methods. The Renal Transplant Outcome Study recruited a cohort of incident KTRs at 3 transplant centers in the Philadelphia area from 1999–2004. KTRs were genotyped for APOL1 RA. Allograft and patient survival rates were compared by the presence and number of APOL1 RA. Results. Among 221 participants, approximately 43% carried 2 APOL1 RA. Recipients carrying 2 APOL1 RA demonstrated lower graft survival compared with recipients with only 1 or none of APOL1 RA at 1 y posttransplant, independently of other donor and recipient characteristics (adjusted hazard ratio 3.2 [95% confidence interval, 1.0-10.4], P = 0.05). There was no significant difference in overall survival or graft survival after 3 y posttransplantation. There was no difference in death by APOL1-risk status (P = 0.11). Conclusions. Recipients with 2 APOL1 high-risk alleles exhibited lower graft survival 1 y posttransplantation compared with recipients with only 1 or 0 APOL1 RA. Further research is required to study the combined role of the recipient and donor APOL1 genotypes in kidney transplantation.