In 2022, the country’s two preeminent kidney associations, the National Kidney Foundation (NKF) and the American Society of Nephrologists (ASN), made changes to the definition of chronic kidney disease (CKD) that will likely revoke diagnoses in an estimated 5.51 million Whites, Hispanics, and other non-Black adults who have the disease, and reclassify CKD to a less severe stage in another 4.59 million non-Blacks. 

This was done to expand treatment eligibility to 434,000 Blacks who are not likely to have CKD and to 584,000 Blacks previously diagnosed with less severe CKD. These changes were not the result of a better scientific understanding of kidney disease; rather they were a response to political pressure from medical students, doctors-turned-advocates, and the government to ignore racial differences in blood creatinine concentrations. (READ MORE: Michelle Wu, Blasted for No-Whites-Allowed Holiday Party, Has Long History of Radical Racial Activism)

Scientists Are Choosing to Ignore Anatomical Differences

CKD affects approximately 37 million adults in the U.S. and can lead to dialysis, kidney replacement, and death. Its diagnosis relies heavily on glomerular filtration rate (GFR), a clinical measure of kidney function. Ideally, GFR is measured directly as the time required to clear an injection of a tracer chemical into the blood. However, this direct measurement is both invasive and expensive. More commonly, GFR is estimated from blood creatinine concentrations, where higher creatinine indicates that the kidneys are less effective in removing waste, toxins, and excess fluids.  

Blacks in the U.S. have higher serum creatinine concentrations than non-Blacks, independent of their directly measured GFR, perhaps partly because they tend to have greater average muscle mass (creatinine is produced by muscle cells). Regardless of the reason, the best approximation of directly measured GFR requires a correction factor for the higher creatinine concentrations in Blacks, which increases Black GFR between 16 percent and 21 percent. (READ MORE: Are Hispanics Next on the Progressive Hate Parade?)

One consequence of this race correction is that, at the same blood creatinine level, a Black patient might not receive the same kidney treatment as a non-Black patient, which is irrelevant. The important fact is that Blacks and non-Blacks received the same diagnosis and medical treatment based on the very best estimate of directly measured GFR (the gold standard, which is not necessarily the same as laboratory creatinine measurements.) Students, activists, and politicians who claim that race correction in this and any other medical algorithm is racial discrimination disregard this important fact.

The Very Real Impact of Discarding Race Correction

The race correction has been used to estimate GFR for over two decades. Laboratory panels were used to present two estimates of GFR, one for African Americans and another for non–African Americans. In 2020, bowing to political pressure, the NKF and ASN leadership created a task force to reassess the inclusion of race in the estimation of GFR. The task force unanimously endorsed a “refit” of the original equation that ignored the creatinine difference between Blacks and non-Blacks. (READ MORE: Racism Is a Many-Feathered Thing)

This produced a biased estimate of GFR that favored the diagnosis of more severe CKD in Blacks while disfavoring its diagnosis and downplaying its severity in non-Blacks. Additionally, their recommendation is projected to deny nephrologists referrals and preparation for dialysis (fistula placements) in 92,000 Whites and other non-Blacks to offer these services to an additional 59,000 Blacks who are less likely to need them. Moreover, the recommendation is estimated to withhold Medicare coverage of kidney disease education and medical nutrition therapy in 1.9 million non-Blacks to offer these services to 206,200 additional Blacks. 

The diversion of health resources for CKD treatment to Blacks is rationalized by the false claim that Blacks bear the greater disease burden. The claim stems from the distortions (biases) introduced by ignoring the race correction factor. Before the introduction of the new race-free GFR formula, the proportion of Americans with CKD was greater in non-Hispanic Whites than Blacks: 8.6 percent vs. 5.6 percent between the years 2003 and 2006; 7.5 percent vs. 5.8 percent between 2007 and 2010, 8.5 percent vs. 6.1 percent between 2011 and 2014; and 8.4 percent vs. 6.6 percent between 2015 and 2018. The original formula also indicated that Whites with CKD were at a greater risk for the two worst outcomes: death and end-stage renal disease (ESRD, i.e., requiring dialysis or transplant to stay alive).

This all changed with the introduction of the race-free definition of GFR, allowing policymakers to claim the percentage of Americans with CKD was greater in non-Hispanic Blacks than Whites: 7.9 percent vs. 5.8 percent between 2005-2008; 8.5 percent vs. 5.9 percent between 2009 and 2012, 8.4 percent vs. 6.3 percent between 2013 and 2016; and 9.1 percent vs. 6.3 percent between 2017-2020. Although there is a greater prevalence of ESRD in Blacks than in Whites, this is largely attributable to a genetic disorder and greater mortality rates among Whites with ESRD. Whatever their race, CKD patients are much more likely to die than to progress to ESRD.

The most commonly cited benefit of the race-free GFR estimate is the expansion of treatment opportunities for Blacks, when in fact, published evidence suggests that in many instances, Blacks are receiving better treatment for CKD than Whites even before the introduction of the new race-free equation. This includes ACEI and ARB drug treatment for keeping the small filters in the kidneys healthy, statin treatment for preventing coronary heart disease, nephrology care, and urine albumin-creatinine ratio testing.

Blacks are also more likely to be self-aware of their CKD and their condition is more likely to be recognized by their usual care physician than White patients (Blacks do lag behind Whites in receiving SGLT2i and GLP-1RA, however). These Black-White treatment differences could be exacerbated by exaggerating the CKD prevalence in Blacks. 

These and other issues regarding race and CKD were recently published in my article appearing in the peer-reviewed science journal Cureus. As a retired biostatistician who’s authored over 170 scientific papers in peer-reviewed scientific journals, I fear that the new race-free GFR estimate is a harbinger of race-driven changes in medical treatment driven by politics rather than science that could endanger public trust in our medical institutions. Recent gallop polls show that the American public holds the medical profession in much higher regard with respect to honesty and ethical standards (58-79 percent) than journalists, lawyers, and members of Congress (9-23 percent). This is not a legacy to be squandered.

Dr. Paul Williams received his Ph.D. in biostatistics in 1986 from Stanford University. Until his retirement, he was the principal investigator on many National Institutes of Medicine grants. He has published over 170 papers on cholesterol, exercise, and gene-environment interactions in peer-reviewed medical journals.