Published in the Journal of the American Society of Nephrology. Here is a link to the article.
Regenstrief Institute authors: Rachel Patzer, PhD, MPH
More than 160 research studies, and counting, have documented racial disparities in kidney transplant access among patients with kidney failure, with a specific emphasis on pronounced inequities affecting Black versus non-Hispanic White patients.1 Notably, a 1998 study revealed significant disparities in key transplant steps, highlighting that Black patients with kidney failure were only half as likely to undergo transplant compared with White patients.2
It is imperative to underscore that race is a social, not a biological, construct, with more genetic variations observed within racial and ethnic groups than between them. Multilevel and multifactorial factors contribute to these disparities and accumulate across the life course, including those at the patient, patient–provider, neighborhood, and system levels. Racism permeates various societal levels and is a driving force of social determinants of health. Historical injustices, such as slavery and redlining, coupled with enduring policies, have resulted in the unequal distribution of material and social resources within institutions, resulting in inequitable opportunities for optimal health for marginalized populations.
Recent endeavors have shifted focus from describing inequities to intervening to redress inequity.1 Over the past decade, several large, multilevel trials targeted health systems or geographic regions with racial disparities in transplant. Noteworthy progress has been made by initiatives, such as the Southeastern Kidney Transplant Coalition, whose mission is to improve access and reduce disparities in kidney transplant access; the development and implementation of collaborative pragmatic trials have reduced racial disparities in the proportion of Black patients with kidney failure referred to the transplant waiting list in the Southeastern United States and attenuating Black versus White racial disparities in waitlisting among US dialysis facilities with low waitlisting.3
Policy changes have also played a pivotal role in addressing inequities in access to kidney transplantation. Over the past two decades, alterations to the kidney allocation system, such as the 2003 removal of priority on the basis of HLA-B matching4 and the 2014 kidney allocation system recalibration of waiting time,5 significantly reduced racial disparity in deceased donor kidney transplant. The Advancing American Kidney Health Initiative, launched in 2019, explores alternative payment models with a focus on improving waitlisting or living donor transplantation. The ESRD Treatment Choices model uses a health equity incentive that rewards ESRD Treatment Choices participants who improve transplant (and home dialysis) rates among Medicare and Medicaid dual-eligible or low-income subsidy recipients. The 2023 policy change mandating transplant centers to assess waiting lists and submit modifications for Black candidates using race-inclusive eGFR equations represents a promising stride against systemic racism.
Fast forward to 2024, where has all of this left us? Is the glass part-empty or part-full? In the past decade, the United States has witnessed a sustained reduction in the Black versus White racial disparity gap in access to deceased donor kidney transplant, and in 2022, the deceased donor kidney transplant was highest among waitlisted Black patients with kidney failure compared with any other racial group waitlisted (Figure 1).6 In 2021, more Black patients were waitlisted compared with White patients (12.4% of Black and 10.9% of White patients with kidney failure), although these proportions are unadjusted and do not account for younger age at presentation of kidney failure among Black compared with White patients.7 The optimist in me wants to proclaim that the glass is part-full.
However, our optimism must be tempered. While we can pause and celebrate these improvements, our work here is not complete, where concurrent disparities in deceased and living donor transplant continue to exist. While racial equity in deceased donor kidney transplant among waitlisted patients seems to have been achieved on average, there are still subsets of the population where we see stark inequities. Adjusted analyses reveal that racial disparities in waitlisting persist.5,8 Furthermore, racial disparities in living donor transplantation have also widened, with Black living donors decreasing from 11.9% in 2011 to 7.6% in 2022.6 Native Americans and Pacific Islanders with kidney failure have lower rates of both waitlisting and transplantation, and Native Americans had a 14% decrease in the rate of kidney transplants from 2011 to 2021.7 These groups are often removed from research studies because of small sample size, so the available data are inadequate to both measure and address these inequities.
Notably, the largest racial gaps in access to transplant are among the youngest patients with kidney failure in the United States, where non-Hispanic Black patients aged 18–29 years are 27% less likely to be waitlisted compared with non-Hispanic White patients.8 In children, both active and inactive waitlisting has declined, despite this population having the most life years to gain from kidney transplant,7 and Black and Hispanic children have lower access to waitlisting9 compared with their White counterparts. Future research must examine transplant access by important subgroups within racial and ethnic groups, including race, ethnicity, age, sex, and other sociodemographic characteristics, to ensure equitable access, and we have to move beyond describing inequities to interventions.
Recent federal actions signal a turning point. The 2022 National Academies of Sciences, Engineering, and Medicine report has prompted sweeping reforms, exemplified by the commencement of the federally supported Organ Procurement and Transplantation Network Modernization Initiative in September 2023, with a focus on advancing equitable access to transplantation to standardize waitlist practices. The establishment of the Organ Transplantation Affinity Group further demonstrates the potential for a coordinated effort between Centers for Medicare & Medicaid Services and the Health Resources and Services Administration to strengthen accountability and performance for equitable organ transplantation. Current efforts by the United Network for Organ Sharing Data Advisory Committee to define data elements needed for national prewaitlisting data collection, including measures of social risk factors before waitlisting, are a step in the right direction to ensuring transparency in the transplant process.
Yet, optimism for these federal initiatives must be balanced by a realistic assessment of future challenges and uncertainties because long-term effects are yet to be determined. The collection of prewaitlisting data and the recently announced change to the Centers for Medicare & Medicaid Services-2728 form to include a measure for whether the patient has been referred for transplant and the date of referral to a transplant center will help us pinpoint inequities in the early steps of the transplant process, so we can more effectively invest resources to intervene. However, as we have seen with other federal changes, there is a potential for unintended consequences, including the potential to exacerbate racial disparities because of the inefficiencies that may come with an increase in low-quality referrals and limited staffing to handle the increased flux of referrals and evaluations within transplant centers. It will be important to continue to monitor the transplant access pathway over time to ensure equity in access.
In addition, research studies often do not capture important social constructs critically important for the patient, and race is often used as a proxy for many social constructs. Measuring the effect of racism necessitates a more comprehensive understanding of the lived experience of racism and the downstream consequences of racism throughout one’s entire life, yet research often focuses on patients at the time of diagnosis of kidney failure. Limited information about social challenges beyond insurance status limits insights into upstream data on an individual’s lifetime exposure to racism (and classism, sexism, etc.). While we have excellent data on when patients are diagnosed with kidney failure, we know little about their progression from CKD to kidney failure, and we have no national surveillance data on the important prewaitlisting steps and inequities that exist in access to preemptive kidney transplantation.
Finally, it is critically important that researchers studying racial disparities use a conceptual framework that incorporates the fundamental causes (and the interplay of those causes) of racial inequities in access to kidney transplantation.10 Examples of structural racism, such as redlining, the race-based exclusionary practice barring Black residents from buying homes in certain neighborhoods, is an upstream, fundamental cause of the associations we continue to see when we use race as an exposure variable in our research studies and often oversimplify our conclusions of effects, implying that the causal pathway is on the individual patient level. This has important implications for how we address racial disparities in transplant—we have to do more than individual-level interventions (e.g., patient education) alone and move toward interventions that target upstream social risk factors at multiple levels (patient, neighborhood, provider, health system, etc.) and the policies that cause the inequities in the first place. The recent National Institute of Diabetes and Digestive and Kidney Diseases workshop focused on designing interventions to address structural racism and reduce kidney health disparities is an excellent example of the key domains to address the unjust systems and policies that continue to perpetuate inequities in access to kidney transplantation: apply an antiracism lens, promote structural interventions, target multiple levels, promote effective community and stakeholder engagement, improve data collection, and advance health equity through new health care models.11
While acknowledging recent strides, the journey toward equity in kidney transplantation is far from complete. Sustained commitment and continued research are critical to fill the remaining gaps in our understanding to ensure equitable access for all individuals with kidney failure.
Authors
Rachel Patzer1
Author Affiliations
1Regenstrief Institute, Indianapolis, Indiana, and Department of Surgery, Indiana University School of Medicine, Indianapolis, Indiana.
