SFVAHCS Researchers Lead Efforts in Race-Free Approach to Kidney Health

In late September, a joint task force put together by the National Kidney Foundation (NKF) and the American Society of Nephrology (ASN), issued their recommendations on Reassessing the Inclusion of Race in Diagnosing Kidney Diseases. The national task force, which consisted of kidney clinicians and researchers, as well as patient advocates, was co-chaired by the San Francisco VA Health Care System’s (SFVAHCS) very own Dr. Cynthia Delgado. The task force recommended that current race-based equations should be replaced by a substitute that is accurate, representative, unbiased, and provides a standardized approach to diagnosing kidney diseases.

The call for race-free medicine comes at a pivotal time in our history, where larger societal reassessments of race and equity have been brought to the health care conversation as well. It is through the concerted activism from health equity advocates, students, and providers across the health care sector that removing race as a determinant of kidney function became an issue worth tackling.

This issue stems from the use of “estimated glomerular filtration rate” (eGFR), which is the current formula used to diagnose and capture the severity of chronic kidney disease. For over two decades, eGFR has been the leading test that is based on measurement of the levels of creatinine in the blood. (Creatinine is a waste product predominantly from the normal breakdown of muscle tissue.)

Starting in 2013, a group of researchers, led by SFVAHCS’ Dr. Michael Shlipak, published research that compared the creatinine-based eGFR test to a test that measured a protein in the body called cystatin C. The paper’s findings include the conclusion that elevated levels of cystatin C more accurately predict higher rates of heart disease, stroke, and death among elderly people with no known kidney problems than the creatinine test. They showed that unlike creatinine, cystatin C was not dependent on muscle mass. The creatinine test was adjusted for use with Black individuals, who tend to have greater muscle mass on average than white individuals. However, the amount of muscle mass varied widely between all races and the overlap among races made the “adjustment” misleading in individual patients.  The cystatin C test, on the other hand, provides an estimate of kidney function independent of muscle without the use of race as a factor.

In its report, the task force recommended increased use of cystatin C combined with creatinine for a reliable way to check kidney function. The NKF and ASN “now urge all laboratories and healthcare systems nationwide to adopt this new equation to estimate GFR as rapidly as possible so that we can move toward a consistent approach of diagnosing kidney disease that is independent of race.”

Dr. Carl Grunfeld, SFVAHCS’ Associate Chief of Staff for Research and Development, celebrates these findings. “Simply put: this is the embodiment of research put into action for our patients,” said Grunfeld. “The fact that we are leading the way in using a race-free approach to determining health diagnoses and outcomes is a testament to the strong-willed commitment of our health care system to innovative research and health care equity.”