Is the Updated Kidney Allocation System Working?

Purpose of Review: In December 2014, the current kidney allocation system (KAS) was implemented after over 10 years of development by the OPTN Kidney Committee. The Kidney Committee noted several limitations with the prior kidney allocation schema and sought to improve many of these limitations. This review will discuss those goals and the available results at a 2-year review. Recent Findings: Two-year results of the new kidney allocation system: This system increased the allocation of allografts with longer expected function as estimated by the Kidney Donor Profile Index (KDPI) to those patients with longer expected post-transplant survival as estimated by the recipients’ EPTS score or the estimated post-transplant survival score. A large increase in transplantation to those who are highly sensitized, calculated panel reactive antibody (CPRA) 98% or greater has also occurred as planned. Redefining the start of waiting time to the start of chronic dialysis time resulted in a great increase in minority transplantation and to those with a long time of dialysis. There was a small increase in transplantation to blood type B candidates. Challenges: Organ discards have still increased compared to before the implementation of the new KAS, likely due to factors not addressed by the KAS such as the regulatory concerns (performance metric flagging) and financial costs of transplanting higher KDPI organs and higher EPTS candidates. There was a large “bolus” effect in the first year, and possibly still ongoing, regarding increased access to very highly sensitized patients and those with very long dialysis waiting time. These last two patient populations, along with increased cold ischemic times due to 10% more of all transplants being non-local transplants, likely resulted in the slight decrease of 1-year outcomes and increase in DGF compared to pre-KAS, as well as decrease in the 0-ABDR mismatch transplants by 57% at the first year. Summary: Two-year results of the new KAS show that most of the intended goals of the policy are being realized, namely longevity matching, equitable access to transplantation for ethic groups and for those with equivalent dialysis time, and sensitized patients. Policymakers are still following the long-term outcomes from increased transplantation of the highly sensitized and outcomes from the higher DGF rates likely from increased cold ischemic time of non-local transplants and from transplant into patients with very long dialysis times. The hard decision-making process is still in play, balancing equity in access compared to utility: long-term successful graft and patient survival, particularly in a system that has much greater demand for deceased donor allografts than supply.