Racial/Ethnic Disparities in Waitlisting for Kidney Transplantation before and after the New National Kidney Allocation System

Importance: The United Network for Organ Sharing implemented a new national kidney allocation system (KAS) in December 2014 in part to address longstanding racial and ethnic disparities in access to deceased donor kidney transplantation in the U.S.

Objective: To assess the impact of KAS on placement on the national deceased donor waiting list (waitlisting) among U.S. end stage renal disease (ESRD) patients and to evaluate whether racial/ethnic disparities in waitlisting have changed since KAS implementation.

Design, Setting and Participants We examined waitlisting pre- and post-KAS among incident (N=1,253,100) and prevalent (N=1,556,954) ESRD patients from the United States Renal Data System database from 2005 to 2015 using multivariable time-dependent Cox models and interrupted time-series models.

Main Outcomes and Measures: The main outcome of this study was waitlisting, and the secondary outcome was change in racial/ethnic disparity in waitlisting pre- and post-KAS.

Results: Among 1,253,100 ESRD patients who started dialysis in 2005-2015, the annual incidence rate of waitlisting among all patients steadily increased from 17.7 per 100 person-years in 2005 to 22.7 per 100 person-years in 2014, but slightly declined in 2015 for all racial/ethnic groups. In adjusted analyses, the rate of waitlisting among incident ESRD patients was 9% lower post-KAS (HR: 0.91; 95% CI: 0.90-0.93), and the largest declines in waitlisting were observed among Caucasians (HR: 0.89; 95% CI: 0.87-0.91), followed by Hispanics (HR: 0.90; 95% CI: 0.87-0.93), Asians (HR: 0.92; 95% CI: 0.87-0.97), and African-Americans (HR: 0.96; 95% CI 0.93-0.98). Pre-KAS, African-American patients had a 19% lower rate of waitlisting vs. Caucasians (HR: 0.81; 95% CI 0.80-0.82); following KAS, this disparity was reduced to 12% (HR: 0.88; 95% CI: 0.85-0.90). On average, the monthly rate of waitlisting was 55.0/10,000 prevalent ESRD patients (57.1/10,000 for Caucasian, 46.7/10,000 for AA, 62.0/10,000 for Hispanics, and 80.6 for Asian; p<0.001) in the pre-KAS era. In the post-KAS era, the rates declined to 46.1/10,000 (48.9/10,000 for Caucasian, 38.4/10,000 for AAs, 46.4/10,000 for Hispanics, and 66.4/10,000 for Asians; p<0.001) respectively. In time-series analyses of the prevalent dialysis population, the overall waitlisting rate decreased by 3.45/10,000 per month (3.57/10,000 for Caucasians, 3.50/10,000 for AAs, 4.56/10,000 for Hispanics and 5.43/10,000 for Asians) after KAS (p<0.001).

Conclusions and Relevance: Waitlisting declined among both incident and prevalent ESRD patients after a major change in the national kidney allocation policy. Racial disparity in waitlisting among African-Americans vs. Caucasians declined in KAS, but a 12% racial disparity in waitlisting remains.