A. C. Perez-Ortiz1,2, E. Heher1, N. Elias1 1Massachusetts General Hospital,Transplant Center,Boston, MA, USA 2Yale University School Of Public Health,New Haven, CT, USA
Introduction:
The new Kidney Allocation System (KAS) aimed to improve transplantation rates and to address other core needs of deceased donor (DD) kidney allocation. Three years after implementation the regional effects of KAS have not been well studied. Since the United States (US) is heterogeneous, particular states might have experienced significant improvements compared to others. We here aimed to test if such regional differences existed after KAS implementation.
Methods:
We abstracted regional and state data on DD from the Organ Procurement and Transplantation Network, end-stage renal disease prevalence from the US Renal Data System, and US Census, and constructed Poisson regression models to estimate kidney transplant incidence ratios (IRs) by region compared to the national average between 2012–2017. We also tested the additive effect of KAS policy by average marginal effects (AMEs), specifically in the post-implementation period (2015 – 2017) regionally. and plotted our findings in a 50-state choropleth map where lighter colors represent regions with the highest improvement and darkest null effects post-KAS.
Results:
KAS impact was different across regions in two ways. First, the multiplicative effect of KAS post-implementation, measured by IRs, significantly increased the base rate by a factor of 1.16 and 1.09 in regions six and ten respectively. Second, the additive effect of KAS (2015 onward), measured by AMEs, significantly improved the expected mean number of transplants in regions 2, 3, 4, 5, and 9 (Figure). KAS was most impactful in Southern -states with both IRs and AMEs were higher than the national average. In comparison, the mid-west and north-west regions had the lowest AMEs.
Conclusion:
KAS had a higher impact in Southern states improving deceased donor kidney transplant compared to other regions in the US. KAS regional effect warrants exploration, specifically to identify characteristics driving the increase in transplantation so that public policies can be improved accordingly.?
