Favorable Living Donor Kidney Transplantation Outcomes within a National Kidney Exchange Program: A Propensity Score Matching Analysis

BACKGROUND: KEPs (kidney exchange programs) facilitate living donor kidney transplantations (LDKT) for patients with incompatible donors, who are typically higher risk than non-KEP patients because of higher sensitization and longer dialysis vintage. We conducted a comparative analysis of graft outcomes and risk factors for both KEP and non-KEP living donor kidney transplants. METHODS: All LDKTs performed in the Netherlands between 2004-2021 were included. The primary outcome measures were one-, five- and 10-year death censored graft survival (DCGS). The secondary outcome measures were delayed graft function (DGF), graft function, rejection rates and patient survival. We used a propensity score matching model to account for differences at baseline. RESULTS: Out of 7536 LDKTs, 694 (9%) were transplanted via the KEP. Ten-year graft survival was similar for KEP 0.916 (95% CI: 0.894 - 0.939) and non-KEP 0.919 (0.912 - 0.926, p = 0.82). We observed significant differences in five-year rejection (12% vs 7%), and five-year patient survival (KEP: 84%, non-KEP: 90%), which was non-significant after propensity score matching. Significant risk factors for lower graft survival included high donor age, re-transplantations, extended dialysis vintage, higher panel reactive antibodies, and nephrotic syndrome as the cause of end-stage kidney disease . CONCLUSIONS: Transplantation via KEP offers a viable alternative for patients lacking compatible donors, avoiding specific and invasive pre- and post-transplant treatments. KEP's similar survival rate to non-KEP suggests prioritizing KEP LDKT over deceased donor kidney transplantation, desensitization, and dialysis. However, clinicians should consider the identified risk factors when planning and managing pre- and post-transplant care to enhance patient outcomes. Thus, we advocate for the broad adoption of KEP and establishment in regions lacking such programs, alongside initiation and expansion of international collaborations.