Johns Hopkins Health System Adopts Race-Free Kidney Function Equation


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The Johns Hopkins Health System will no longer use a long-standing clinical standard that factors a patient’s race into kidney function tests. The transition to a new standard of evaluating kidney function will specifically eliminate whether a patient is “African American or non-African American” as a modifier to check how well a patient’s kidneys are working. The change to the new race-neutral assessment means thousands of Black people living with chronic kidney disease (CKD) could gain access to specialty treatment or transplantation for the first time.

Removing race from the calculation for kidney disease follows recent national recommendations from both the National Kidney Foundation and the American Society of Nephrology that say race modifiers should not be included in equations used to estimate kidney function because race is a social, not a biological, construct.

“There are not biological differences in the kidney attributable to race, and therefore it should not be considered in the equation for kidney function,” says Sherita Golden, M.D., M.H.S., chief diversity officer at Johns Hopkins Medicine. “This is an evidence-based decision that is really important in potentially narrowing gaps in kidney disease disparities. I’m proud of our leadership for taking this necessary step toward achieving health equity and eliminating structural racism in medicine.”

In the area of nephrology, doctors have long estimated kidney function by calculating what’s called the estimated glomerular filtration rate (eGFR). The calculation is used to determine who should be diagnosed as having CKD, receive specific medications, go on dialysis or be a candidate for a kidney transplant. Historically, the equation considered four factors: age, gender, race and levels of creatinine — how well a person’s kidneys filter waste. As kidney disease gets worse, the eGFR number goes down. The algorithm calculated different eGFR scores for Black and non-Black patients, based on studies that found that levels of creatinine were higher for Black people compared with non-Black people. The reasons for this difference are not clear.

Use of the previous algorithm gave Black people higher estimates of GFR than non-Black people for the same level of creatinine, which might result in delays for treatment. For example, normal adult kidneys function around or above an eGFR score of 90. If a patient’s score hits 20 or below, they can be added to the kidney transplant waitlist. Under the previous algorithm, Black patients had points added to their score, which could lead to delays in Black patients being referred for life-saving treatments such as a kidney transplant.

“Eliminating the race-based adjustment may lead to several positive clinical outcomes, including more time for management and referral of early kidney disease, earlier consideration for transplant listing and more careful medication decisions for Black patients,” says Deidra Crews, M.D., Sc.M., professor of medicine in the Division of Nephrology and a member of the task force that recommended the new equation. “Time is of the essence; if a patient does have kidney disease, finding out earlier could make a difference in the person’s long-term health.”

According to the National Kidney Foundation, there are 37 million people in the United States living with chronic kidney disease, with Black adults three times more likely to suffer from kidney failure than white adults.

“We know that, historically, Black people have suffered disproportionately from chronic kidney disease,” says Golden. “We hope that updating the method we use to diagnose kidney disease will not only lead to more equitable health care for all of our patients, but also bring greater awareness to the inherent flaws in many race-based medical measurements.”