Comparison of Outcomes for Paired Kidney Exchange, End Chain, and Directed Donor Living-Donor Kidney Transplants

Background: Living donor kidney transplants (LDKT) comprise roughly a quarter of all kidney transplants in the US. Directed donor LDKT (D-LDKT) remains the most common, but rising rates of Paired Kidney Exchange LDKT (PKE-LDKT) and End Chain LDKT (EC-LDKT) have expanded access for many waitlisted patients. This study compares graft and patient survival across these LDKT sources. Methods: We evaluated adult LDKT recipients at the University of Pennsylvania between 1/1/2015 and 11/30/2023. Clinical data on recipient, donor, and transplant characteristics were collected from electronic medical records. Any graft or patient loss was analyzed using Kaplan Meier survival analysis. Results: Donor age, cold ischemia time, zero HLA mismatch (all p<0.001), and recipient pre-emptive transplant (p=0.002) differ significantly across LDKT groups. On Kaplan Meier analysis, there is no difference in patient survival (p=0.12; Fig 1) or kidney graft survival (p=0.81; Fig 2). Conclusion: Our study shows similar graft and patient outcomes across D-LDKT, PKE-LDKT and EC-LDKT pathways. Increased participation of transplant programs in PKE and EC-LDKT can improve access to LDKT for more waitlisted patients.Fig 2Fig 1 Baseline Characteristics of the Cohort - Directed Donor LDKT (N = 413) NKR End Chain (N = 49) NKR KPD (N = 124) P-value Recipient age (years) 49 (14) 49 (12) 49 (14) 0.79 Recipient female gender 143 (34.6%) 25 (51.0%) 53 (42.7%) 0.05 Recipient pre-emptive transplant 248 (60.0%) 18 (36.7%) 60 (48.4%) 0.002 Donor age (years) 46 (12) 55 (12) 42 (12) < 0.001 Donor female gender 279 (67.6%) 33 (67.3%) 75 (60.5%) 0.78 Cold ischemia time 1.6 (1.6) 4.7 (3.4) 9.8 (4.6) < 0.001 Zero HLA mismatch 19 (4.6%) 0 (0.0%) 2 (1.6%) <0.001