Updating the kidney donor risk index: Removing donor race and hepatitis C virus status.

This study reports the results of a recalculation of the kidney donor risk index (KDRI) formula requested by the Organ Procurement and Transplantation Network's Minority Affairs Committee to remove the donor race and hepatitis C virus (HCV) status variables. The updated KDRI model was fit on adult, deceased donor, solitary kidney, first-time transplants from 2018-2021. Deceased donors from 2018 through 2021 were included in a counterfactual analysis to evaluate how the kidney donor profile index (KDPI) would change if race and HCV seropositivity were excluded. When recalculating the original KDRI models on 2018-2021 transplants, the donor Black race coefficient was only slightly lower (β = 0.18 in the original model; β = 0.15 in the 2018-2021 cohort), while the donor HCV seropositivity coefficient was substantially lower (β = 0.24 in the original model; β = -0.04 in the 2018-2021 cohort). Among Black donors, the probability of being classified as KDPI ≤20% increased and the probability of being classified as KDPI >85% decreased notably when the Black race and HCV variables were removed from the model. Removing the donor race and donor HCV status variables in an updated KDRI model resulted in more racially equitable KDPI distributions.