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Abstract: SA-PO063

Differences in Transplant Rates Across Race/Ethnicities Post-KAS Implementation

Session Information

Category: Transplantation

  • 1802 Transplantation: Clinical


  • Perez-Ortiz, Andric C., Massachusetts General Hospital, Boston, Massachusetts, United States
  • Elias, Nahel, Massachusetts General Hospital, Boston, Massachusetts, United States

The Kidney Allocation System (KAS) aimed to decrease racial allocation disparity, indirectly improving transplant rates (TR) for non-Whites. 3 years after implementation, we lack evidence of this specific efficacy. We here assess whether the waitlisting and transplant rates across races/ethnicities have improved after KAS implementation.


To assess any systematic difference in US TR (1989-2017) and the effect pre- (1989-2014) and post-KAS (2015-2017), we calculated the slope per year basis. We then, using linear regression, estimated the effect of race/ethnicity on kidney waitlist addition and TR across periods, also addressing donor type for TR. To eliminate improved deceased donation effect, we compared kidney and liver TR. A difference indicates a positive impact of KAS. Finally, we similarly evaluated the rate of change for kidney waitlist additions. We used data from OPTN database and for linear models R.


We show three distinct periods wherein the kidney TR varied. Between 1989–2006 and 2015–2017, there was a significant positive slope, higher in the later. However, between 2006–2014 there was no change in TR. Furthermore, compared to deceased liver TR after KAS implementation (2015-2017), kidney TR increased up to 76% (p=0.02). Before 2015, there were no differences between the two groups (p>0.2). Moreover, kidney TR has steadily risen for non-Whites compared to Whites (p=0.03). KAS implementation increased the rate for non-Whites 13-fold compared to Whites (p=0.04). Lastly, this improvement was not mirrored in the waitlist additions, and KAS did not change the slope.


We have preliminary evidence that KAS allocation has improved TR especially benefiting non-Whites (Blacks, Hispanics, Asians). Waitlist addition did not equally change, arguing for the need to alter referral and listing practice.