Research Grant Aims to Reduce Disparities in Access to Kidney Transplantation for Children and Adults

Sandra Amaral, MD, MHS, Medical Director of the CHOP Kidney Transplant Program, has been leading a study funded by the NIH/NIDDK (R01 DK120886) with co-Principal Investigator Dr. Elaine Ku at the University of California San Francisco to ensure that children and adults in the United States have equitable access to kidney transplantation and living donation. The study began in September 2019 and is called Reaching Equity for Adults and CHildren (REACH) in Transplant.

Kidney transplantation is known to improve survival for patients who reach end-stage kidney disease (ESKD), yet non-Hispanic Black (NHB) and Hispanic children and adults are consistently less likely to receive deceased-donor kidney transplantation, preemptive transplantation (transplant prior to the initiation of chronic dialysis), and living-donor kidney transplantation. Barriers to living-donor kidney transplantation are multifaceted and reflect a complex interplay of individual, community level, healthcare system level and policy level factors. Most interventions to improve living donation have focused on potential recipient and donor education or individual-level barriers. Less attention has been paid to the role of the overall healthcare system, clinical practice variation, and national policy as contributors to persistent disparities.

The REACH-Transplant study has three primary aims, each focused on systemic factors that contribute to racial/ethnic disparities along the transplant process. The first part of the study is a retrospective cohort analysis of children and adults with end-stage kidney disease (ESKD) cared for at leading adult and pediatric transplant centers across the country. Dr. Amaral and her study team will examine whether using ESKD risk prediction models is superior to an absolute estimated glomerular filtration rate (eGFR) approach to equalize time available for transplant preparation in Blacks (vs. whites) with advanced chronic kidney disease (CKD).

Currently, national policies allow adults to accrue waiting time for deceased donors only when their eGFR is less than 20 ml/min/1.73m2 and referral for transplant evaluation is recommended when eGFR is less than 30 ml/min/1.73m2. Most pediatric transplant programs also use eGFR as a cut-off or criteria for transplant referral. The causes for renal disease often vary by race/ethnicity and several disease conditions which progress more rapidly, such as glomerular diseases, are more common in Blacks and Hispanics. Thus, if patients are referred at the same eGFR, but some patients reach ESKD much more quickly than others, not everyone will have the same amount of time to prepare for transplant. Those with more rapid progression of disease may have less opportunities to identify living donors and plan for transplant pre-emptively.

This study hypothesizes that transplant referral based on a patient’s predicted risk to reach ESKD within the following two years (vs. eGFR criteria) will reduce differences in the time available for transplant preparation between Blacks vs. whites. A second aim of the REACH-Transplant study is focused on the living donor candidate evaluation. Recent reports have suggested worse mid- and long-term renal outcomes among Black living donors which may create heightened concern surrounding donor safety. Objective tools to estimate risk of ESKD post-donation have been developed and incorporate age, race and other factors. Yet, standardized thresholds of acceptable risk of donation have not been universally adopted, potentially leading to substantial variability in the risk that is deemed acceptable for a Black (vs. white) donor candidate. Applying objective metrics of risk prediction for ESKD, Dr. Amaral and her study team are examining differences in the determination of medically suitability and unsuitability by race/ethnicity among living donor candidates who have been evaluated across the country.

The final aim of the study is targeted at learning more about the routine health monitoring of living donors. While there is a lot of attention given to ensuring donor safety through rigorous donor evaluation, less attention is focused on ensuring preventive care for donors. Lack of routine health monitoring could lead to later detection of hypertension and other risk factors for CKD. Some studies have suggested greater barriers to health insurance for Black (vs. white) donors. The REACH-Transplant study will assemble of cohort of living donors who have donated at least three years prior. The study will collect survey data to improve our understanding of barriers faced by living donors in terms of obtaining routine health monitoring. The study will also provide direct health screening to donors for blood pressure, kidney function and diabetes. The study is particularly interested in capturing living donors who donated to their children with ESKD since the team hypothesizes that these donors may be at increased risk of neglecting their own healthcare needs due to their caregiver roles and responsibilities.

Taken together, the REACH-Transplant study aims to identify objective approaches to reduce disparities in access to transplant across race/ethnicity, with particular attention to improve systems for transplant referral timing, living donor candidate evaluation and living donor follow-up.