A deceased-donor kidney-transplant waiting list equation that included race as a factor resulted in many Black patients spending less time on the waiting list for the operation than people of other races — meaning that as a group, they received transplants later than they should have, if at all.
However, recent research by Jesse Schold, PhD, professor of transplant surgery at the University of Colorado Department of Surgery, shows that after a new equation was rolled out that eliminates race from the criteria, many Black patients took their rightful place in line once transplant centers went back through their records to find Black patients who had been unfairly moved down the list under the old system.
New priorities
“Historically, the way patients are prioritized, meaning how they are lined up to receive a deceased donor kidney transplant, is a function of certain biological factors, but it’s largely due to how long they've been on the waiting list,” Schold says. “Under the previous system, the formula to estimate a patient’s kidney function — known as GFR — used race as one of the components of the model, but it estimated Black patients’ GFR, which is the numeric quantification of kidney function, as higher systemically than that of non-African American candidates. Since you have to have a GFR of less than 20 to receive priority points on the waiting list — which is how you move up on the list — African American patients would have less time qualifying if they were listed for a kidney transplant prior to the initiation of dialysis.”
In 2023, kidney transplant programs in the United States were mandated by the Organ Procurement and Transplantation Network to identify all Black candidates on their kidney waiting lists and evaluate potential modifications of waiting time based on a new race-neutral estimated GFR (eGFR). Looking at transplant data over the following year, Schold found that 32% of Black candidate listings received an eGFR modification of waiting time priority. The majority of those patients were older, female and had a higher body-mass index. Waitlist modification was associated with a significantly higher rate of deceased donor transplantation.
“What can happen is African American patients will have a delta, so they may have been listed at a GFR of, say, 16, but if they were to use the race-neutral equation, and you can find the time when they would have qualified earlier, they should have gotten that much more time on the waiting list,” he says. “And that delta in time, in some cases, is not trivial. They can receive additional years of priority time if they were to use the race-neutral equation, which would suggest that they would get a longer waiting time and higher priority on the waiting list.”
Investigating policy changes
In the research, Schold found variation by transplant center in terms of how many candidates received wait-time modifications, a data point that could have several explanations, he says.
“It could be that some centers were better at identifying labs, or it could be that systematically there are more patients that qualified at some centers,” he says. “It suggests that some patients either had more lab values available or were able to obtain them more easily than others. There may also be socioeconomic factors that drive some of these effects, because access to health care increases your likelihood of having additional tests. Those patients who had better access to care probably also had better access to prior lab values, so the socioeconomic component of biases that exist within the system were not directly incorporated. That might be a continuing question of interest, given that this policy is still in place.”
Remedying disparities
Schold, whose research specialty is disparities in transplant surgery, says he is pleased that this research shows the positive result of an effort to address those disparities and create a solution to remedy them.
“I think the identification of biases that have resulted from equations in health care is something which is more broadly been recognized, for the better now that we understand how they can manifest,” he says. “This was a circumstance in which, in general, the transplant community acted relatively efficiently to reconcile some of those biases that existed, so overall it created a more equitable system.”
