Removing Race Based Glomerular Filtration Rate (GFR)

Prabdeep Uppal, DO
Christiana Care EM/FM PGY2

“Institutionalized racism is the elephant in the room that has not been addressed. We have put this social construct, as enormous as it is, to become an obstacle to everything that we do, and we pay the price.”  Dr. Clive Callender

Our current race-based algorithm for chronic kidney disease (CKD) is delaying diagnosis and treatment in the Black population. Both the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and Modification of Diet in Renal Disease (MDRD) equations include adjustments based on age, sex, and race. Adjusting for Black race using the MDRD and CKD-EPI equations accounts for an approximately 18% and 16% increase in eGFR, respectively.¹ This adjustment is based on three flawed, small, poor-quality studies published between the 1970s and 1990s that assume inaccurate racial differences in muscle mass and nutritional status.¹

We as physicians fail to diagnose early stages of CKD in the Black population due to this overestimation of GFR, leading to a delay in secondary prevention. Using these flawed equations, we miss the diagnoses, and our patients miss crucial interventions including nephrology referrals or eligibility for kidney transplantation. Despite the Black population constituting only 13% of the overall United States’ population, Black patients disproportionately account for a more than 35% of all patients in the United States receiving dialysis for kidney failure.²

In 2021, the National Kidney Foundation and the American Society of Nephrology (NFK-ASN) found that of the many approaches to calculating GFR, CKD-EPI using creatinine without race minimizes bias, inaccuracy and should be used going forward.³ CKD-EPI using creatine without race does not disproportionately affect any one group of individuals, and it’s immediately available in all United States labs. As providers, we can reduce health inequities by advocating for our patients and eliminating race based ­­­GFR in our home institutions.

Sources:

1. Eneanya ND, Yang W, Reese PP. Reconsidering the consequences of using race to estimate kidney function. JAMA. 2019;322(2):113-114. doi:10.1001/jama.2019.5774
2. Estimated Glomerular Filtration Rate (eGFR). (2021, September 23). National Kidney Foundation. https://www.kidney.org/atoz/content/gfr
3. Delgado C, Baweja M, Crews DC, et al. A Unifying Approach for GFR Estimation: Recommendations of the NKF-ASN Task Force on Reassessing the Inclusion of Race in Diagnosing Kidney Disease [published online ahead of print, 2021 Sep 23]. Am J Kidney Dis. 2021;S0272-6386(21)00828-3. doi:10.1053/j.ajkd.2021.08.003
4. Arnold C, Price LC. For black and brown kidney patients, there are higher hurdles to care. Scientific American. https://www.scientificamerican.com/article/for-black-and-brown-kidney-patients-there-are-higher-hurdles-to-care/. Published December 16, 2020. Accessed October 13, 2021.