As part of the celebration of U.S. Medicine’s 60th anniversary, we are profiling some of the remarkable achievements in federal medicine over the last six decades. In the third of this series, we highlight the work of Cynthia Delgado, MD, nephrologist, associate chief of nephrology, and director of the dialysis program at the San Francisco VAMC. In a landmark effort to eliminate racial bias in kidney care, Delgado led the transformation of kidney function calculations, leading to more equitable transplantation practices at the VA and beyond.
Cynthia Delgado, MD, Nephrologist, Associate Chief of Nephrology, and Director of the Dialysis Program at San Francisco VAMC
SAN FRANCISCO — For more than two decades, the calculation of estimated glomerular filtration rate (eGFR) — a critical measure of kidney function — included race as a variable. This practice came under scrutiny due to concerns that it negatively affected African American communities and disproportionately delayed care and eligibility for transplantation for Black patients.
“The justification for the inclusion of race in estimating equations stems from the fact that studies showed that Black individuals tended to have higher serum creatinine levels,” Cynthia Delgado, MD, nephrologist, associate chief of nephrology, and director of the dialysis program at the San Francisco VAMC, told U.S. Medicine. “However, the biological reasons behind this difference are not well understood, and it’s unclear how this difference applies to other groups.”
Recognizing the uncertainty surrounding the rationale for these differences and the potential implications for patient care, medical professionals began to question the use of race in eGFR calculations. Over the years, evidence grew that including race disadvantaged Black patients and led to significant disparities in kidney disease outcomes.
To address these concerns, Delgado co-chaired a joint task force formed by the National Kidney Foundation (NKF) and the American Society of Nephrology (ASN) to reassess the use of race in diagnosing kidney disease. Their work led to a recommendation for a unified, race-neutral approach to eGFR estimation across the United States.
“There was no resistance to eliminating the variable,” said Delgado. “The challenge was in figuring out the best way to do it, balancing social responsibility with rigorous science.”
Under the leadership of Paul Palevsky, MD, deputy national executive director of the VHA Kidney Medicine Program, and Susan Crowley, MD, executive director of the VHA Kidney Medicine Program, the VA swiftly implemented the new race-neutral eGFR calculations.
Eliminating race from eGFR calculations is a significant advancement, but Delgado emphasized that it is just one part of addressing broader health disparities.
“Some have asserted that the observed health and health care disparities that disproportionately affect African Americans are attributable to the inclusion of race in the kidney function estimation,” she pointed out. “However, there’s no conclusive evidence that this is the main cause. Disparities in kidney transplants existed before race was included in eGFR calculations and are also influenced by factors like access to specialized kidney care, social determinants of health, and genetics.”
The impact of changing the eGFR calculation has been profound. Following the NKF-ASN Task Force’s recommendations, the Organ Procurement and Transplantation Network (OPTN) Board of Directors eliminated race-based kidney function estimation from transplant listings, effective June 27, 2022, and applied the change retroactively. “This resulted in over 2,500 kidney transplants and reduced wait times by about two years,” Delgado reported.
“More recently, OPTN has continued its work by removing race from the Kidney Donor Risk Index (KDRI) calculation,” Delgado noted. “The KDRI is a mathematical formula that estimates the quality of a donated kidney. Under the new equation without race, kidneys donated by individuals will be graded by known biological parameters without the inclusion of a social construct. With these changes, kidney transplant is more equitable.”
Delgado’s efforts have directly contributed to improving access to life-saving kidney transplants for Black Americans, who are disproportionately affected by kidney failure yet have historically faced barriers to transplantation.
In recognition of her monumental contributions, TIME magazine named Delgado to its TIME 100 Health list of the most influential individuals in health on May 6, 2024. Her inclusion underscores the significance of her work in transforming kidney care and advancing health equity.
Beyond the estimation of kidney function, Delgado advocates for a comprehensive approach to improving kidney care. “Screening and frequently re-screening patients who are at risk of kidney disease are of the utmost importance,” she emphasized.
Increasing access to advanced testing methods is also crucial. “We also need to increase access to cystatin C testing to confirm chronic kidney disease,” Delgado noted.
Addressing the affordability of treatments is another priority for Delgado. “The high cost of newer kidney function-preserving medications can limit access to treatments many individuals need.”