PHOENIX — Defining health equity as “the elimination of avoidable disparities in health outcomes among socially disadvantaged groups,” Darren Stewart, MD, a research scientist at the United Network for Organ Sharing, outlined how the Organ Procurement and Transplantation Network goes about monitoring the transplantation process and also named the four factors most strongly associated with disparities in access to kidney transplant.
During his presentation at Cutting Edge of Transplantation: Transplant Summit, Stewart said the first step to reaching health equity is to recognize that not everyone in the health care system starts at the “same, level playing field with respect to their health or their social determinants of health.” Once this is acknowledged, he said policies and interventions can be implemented to mitigate these disparities. However, he noted that not everyone agrees that measuring group-level differences in health care is the appropriate avenue for reaching health equity. Some, he said, are proponents of the model of patient engagement, in which “the patient is given full volition to pursue the highest possible standard of health, even if that results in an unequal distribution of health for all.” According to Stewart, the focus here is on the fairness of the decision-making process, rather than the result.
The methodology that the Organ Procurement and Transplantation Network (OPTN) uses to track potential disparities in the transplantation process includes two components, which complement each other by answering different questions. One looks at disparate treatment in the system, which could be embedded in patient policy or in decision-making biases, and the other considers the disparate impact on members of different groups (or the result).
Stewart contended that tracking equity can improve the system in the following three primary ways:
- identify “trouble spots,” or areas where one might not expect to see a disparity, that need further attention;
- spur and inform healthy debate on policy; and
- aid in weighing tradeoffs with other goals or help assess potential risk to equity that may accompany certain policies (eg, “Is it acceptable for the system to become less equitable for certain candidates if more transplants are happening?”).
Stewart also addressed the difficulty in determining which factors are associated with access to transplant. As an example, he noted that while Asian patients have a disproportionately low likelihood of being transplanted relative to their presence on the waitlist, they also have harder to match blood types and live in parts of the country that have lower transplant rates. Therefore, OPTN methodology “aims to isolate the association of a variety of factors [including race/ethnicity, biological factors, geography, socioeconomic status and insurance type] by adjusting for other factors.” For instance, he said, after adjusting for such factors as blood type and donor service area, differences in transplant access among race and ethnicities “go away completely.”
Speaker highlights importance of tracking equity and disparities in transplantation access.
Source: Adobe Stock
Through this type of tracking, OPTN found the disparity measure has decreased by approximately 40% after the implementation of the New Kidney Allocation System. They also uncovered the factors most associated with disparities. Donor service area was number one on the list (also most strongly associated with disparities in access to lung and liver transplant), followed by cPRA, blood type (patients with types O or B had lower transplant rates than patients with A or AB) and prior kidney transplant.
Stewart said there is little association, if any, between disparities in access and demographic or socioeconomic factors (including community risk score, gender, ethnicity or education level).
Currently, the OPTN is refining its methodology to include transplant center-level variation.
Stewart concluded his talk by telling audiences about an app, available on the OPTN website, that allows users to monitor equity in the allocation system and look at past trends (with the equity and access dashboard). – by Melissa J. Webb
Stewart D. Defining equity — How are disparities and equity defined in transplantation? Presented at Cutting Edge of Transplantation: Transplant Summit. March 5-7, 2020; Phoenix.
Disclosures: Healio/Nephrology was unable to confirm relevant financial disclosures prior to publication.