Kidney Transplant Candidates With High Frequency Deceased Donor Offers

Changes in organ allocation and regulatory policy have led to significant expansion of deceased donor kidney offers for transplantation in the United States. Transplant rates have increased, however inefficiencies in allocation have also evolved including increased donor kidney nonutilization, resources, and complication rates.

We conducted a retrospective observational study of deceased donor kidney offers in the United States with the Scientific Registry Of Transplant Recipients (SRTR) data between January 1, 2021 and December 31, 2024 using multivariable logistic and negative binomial models.

There were 7,608,578 donor kidney offers to 205,780 candidates with an average 19.4 months follow-up on the waiting list. The median offer per candidate was 17 (interquartile range: 6-46); however 28% of offers (n = 2,128,812) were to 5% of candidates (n = 10,285), and 55% of offers (n = 4,212,693) were to 15% high-frequency candidates (HFC; n = 31,049), who had ≥ 74 offers over the period. HFC were disproportionally aged from 50 to 59 years (incident rate ratio [IRR] = 1.26, 95% confidence interval [CI]: 1.24-1.29, relative to candidates aged 18-39), male (IRR = 1.14, 95% CI:1.12-1.16), Black (IRR = 1.30, 95% CI:1.28-1.31, relative to White), type-O blood (IRR = 1.69, 95% CI: 1.67-1.70, relative to type-A), and body mass index (BMI) ≥ 35 kg/m² (IRR = 1.12, 95% CI: 1.10-1.14, relative to BMI = 20-24 kg/m²). There was a wide heterogeneity in HFC proportions by transplant center (median = 9%, interquartile range: 2%-17%), and centers with the highest HFC proportions had significantly low transplant rates and were more likely underperforming for offer acceptance ratios (OARs). Among candidates who received transplants during the study period, HFC recipients received transplants from older donors, including both deceased and living donors.

Results indicate that organ offers are disproportionately explained by a minority of candidates. Efforts to identify reasons for repetitive offer declines, strategic use of offer filters, and transition of applicable candidates to inactive status may dramatically improve the efficiency of deceased donor kidney allocation.