Small changes to US kidney allocation policy may help reduce geographic disparities in transplantation

In the United States, the length of time it takes a person on the kidney transplant waiting list to receive a transplant varies depending on where that person lives. To distribute kidneys for transplantation, the United States is divided into 58 Donor Service Areas (DSAs), and sometimes the waiting times for kidneys are very different in DSAs that are located next to each other.

In the early 1990s, Tennessee and Florida implemented the Statewide Sharing variance to the national kidney allocation policy. The variance allocates kidneys not used within the procuring donor service area to the rest of the state first before offering them regionally and nationally.

Daniela Ladner, MD, MPH, FACS (Northwestern University) and her colleagues examined the effect of Statewide Sharing on geographic allocation disparity over time between DSAs within Tennessee and Florida and compared them with geographic disparity between the DSAs within a state for all states with more than one DSA (California, New York, North Carolina, Ohio, Pennsylvania, Texas, and Wisconsin).

Over a few years, the waiting times and other measures of geographic disparity that were initially very different in the DSAs within Tennessee and Florida became almost equal. While the geographic disparity was almost eliminated in these two states, it became worse in other comparable states. The findings suggest that directed sharing with neighboring donor service areas can significantly alleviate existing geographic disparity in kidney allocation.

"While this is an experiment from only two states in the US, important lessons can be learned to improve the existing geographic disparity across the nation," said Dr. Ladner. The authors, who are not from either Tennessee or Florida, believe the most important lesson is that rather small changes to the existing system to distribute kidneys can make a significant improvement without leading to harm or unintended consequences.

Study co-authors include Ashley Davis, PhD, Sanjay Mehrotra, PhD, Vikram Kilambi, PhD Candidate, Joseph Kang, PhD, Lisa McElroy, MD, Brittany Lapin, MS, Jane Holl, MD, MPH, Michael Abecassis, MD, MBA, and John Friedewald, MD.