Association of transplant center market concentration and local organ availability with deceased donor kidney utilization

Deceased donor kidneys from higher distressed communities are significantly less likely to be utilized for transplantation

The proportion of kidneys procured for transplantation but not utilized exceeds 20% in the United States. Factors associated with nonutilization are complex, and further understanding of novel causes are critically important. We used the national Scientific Registry of Transplant Recipients data (2010-2022) to evaluate associations of Distressed Community Index (DCI) of deceased donor residence and likelihood of kidney nonutilization (n = 209 413). Deceased donors from higher distressed communities were younger, had an increased history of hypertension and diabetes, were CDC high-risk, and had higher terminal creatinine and donation after brain death. Mechanisms and circumstances of death varied significantly by DCI. The proportion of kidney nonutilization was 19.9%, which increased by DCI quintile (Q1 = 18.1% to Q5 = 21.6%). The adjusted odds ratio of nonutilization from the highest quintile DCI communities was 1.22 (95% CI = 1.16-1.28; reference = lowest DCI), which persisted stratified by donor race. Donors from highly distressed communities were highly variable by the donor service area (range: 1%-51%; median = 21%). There was no increased risk for delayed graft function or death-censored graft loss by donor DCI but modest increased adjusted hazard for overall graft loss (high DCI = 1.05; 95% CI = 1.01-1.10; reference = lowest DCI). Results indicate that donor residential distress is associated with significantly higher rates of donor kidney nonutilization with notable regional variation and minimal impact on recipient outcomes.

Identifying and understanding variation in population-based access to liver transplantation in the United States

We aimed to identify variations in liver transplant access across transplant referral regions (TRRs), accounting for differences in population characteristics and practice environments. Adult end-stage liver disease (ESLD) deaths and liver waitlist additions from 2015 to 2019 were included. The primary outcome was listing-to-death ratio (LDR). We modeled the LDR as a continuous variable and obtained adjusted LDR estimates for each TRR, accounting for clinical and demographic characteristics of ESLD decedents, socioeconomic and health care environment within the TRR, and characteristics of the transplant environment. The overall mean LDR was 0.24 (range: 0.10-0.53). In the final model, proportion of patients living in poverty and concentrated poverty was negatively associated with LDR; organ donation rate was positively associated with LDR. The R2 was 0.60, indicating that 60% of the variability in LDR was explained by the model. Approximately 40% of this variation remained unexplained and may be due to transplant center behaviors amenable to intervention to improve access to care for patients with ESLD.

The New Distance-Based Kidney Allocation System: Implications for Patients, Transplant Centers, and Organ Procurement Organizations

Purpose of Review

The goal of deceased donor kidney allocation policy is to provide objective prioritization for donated kidneys, and policy has undergone a series of revisions in the past decade in attempt to achieve equity and utility in access to kidney transplantation. Most recently, to address geographic disparities in access to kidney transplantation, the Kidney Allocation System changed to a distance-based allocation system—colloquially termed “KAS 250”—moving away from donor service areas as the geographic basis of allocation. We review the early impact of this policy change on access to transplant for patients, and on complexity of organ allocation and transplantation for transplant centers and organ procurement organizations.

Recent Findings

Broader sharing of kidneys has increased complexity of the allocation system, as transplant centers and OPOs now interact in larger networks. The increased competition resulting from this system, and the increased operational burden on centers and OPOs resulting from greater numbers of organ offers, may adversely affect organ utilization. Preliminary results suggest an increase in transplant rate overall but a trend toward higher kidney discard and increased cold ischemia time.

Summary

The KAS 250 allocation policy changed the geographic basis of deceased donor kidney distribution in a manner that is intended to reduce geographic disparities in access to kidney transplantation. Close monitoring of this policy’s impact on patients, transplant center behavior, and process measures is critical to the aim of maximizing access to transplant while achieving transplant equity.