Reassessing race-based clinical prediction tools

Five months ago, AFP published Dr. Bonzo Reddick's editorial "Fallacies and Dangers of Practicing Race-Based Medicine." In this editorial, Dr. Reddick reviewed the limitations of several commonly used clinical prediction tools that employ race as a biologic variable rather than recognizing it as a social construct. For example, he pointed out that the American College of Cardiology / American Heart Association Pooled Cohort Equations (PCE) predict that "a 40-year-old White male smoker has a lower cardiovascular risk than a 40-year-old Black male nonsmoker," or put more bluntly, "being a Black man is more dangerous than smoking." Since then, researchers and policy makers have made considerable progress in addressing the inappropriate use of race in medical decision making.

A Curbside Consultation in the September issue introduced a multiracial patient who is confused by the need to identify as African American, White, or Other so that his clinician can evaluate the appropriateness of statin therapy. If White, his estimated 10-year cardiovascular disease (CVD) risk would be 5.8%; if African American, it would be 17.7%. Similarly, a preprint study using thousands of hypothetical and actual patients concluded that large differences in PCE estimates in Black versus White persons with identical risk factor profiles would have the practical effect of "introduc[ing] race-related variations in clinical recommendations for CVD prevention." Until new cardiovascular risk prediction models are developed that omit race, Drs. Mara Gordon and Isha Marina Di Bartolo suggested that physicians exercise caution when using race as a marker of genetic ancestry; consider alternative approaches to risk stratification; and use social determinants of health as an alternative to demographics.

Turning from the heart to the kidneys, including race in the estimation of glomerular filtration rate (eGFR) has the effect of increasing a Black person's eGFR relative to a White person's with the same serum creatinine level. Consequently, Black patients with chronic kidney disease become eligible for kidney transplants nearly two years later than their White counterparts. Underlying this point, Glenda Roberts, a patient representative to a National Kidney Foundation and American Society of Nephrology Task Force that recommended implementing a refitted eGFR calculation that does not include race, observed in a recent opinion piece that though she self-identifies as Black, learning from a DNA analysis that her ancestry was only 48% African (making her, technically, White) would have gotten her on the transplant list sooner! The Chronic Kidney Disease Epidemiology Collaboration has published new eGFR equations that omit race and incorporate serum creatinine and cystatin C.

A 2007 calculator for predicting the likelihood of a successful vaginal birth after cesarean (VBAC) delivery that includes race-based correction factors for African American and Hispanic women was later challenged for promoting disparities in cesarean rates. Earlier this year, researchers from the National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network unveiled a new VBAC calculator without race variables that has excellent calibration and a similar area under the receiver operating characteristic curve as the previous calculator.

Further work remains to be done. The Agency for Healthcare Research and Quality (AHRQ) posted draft Key Questions for a future systematic evidence report on the impact of clinical algorithms on racial disparities in health and health care. Another AHRQ-funded methods report on racism and health inequities in clinical preventive services and guideline development supported the U.S. Preventive Services Task Force's proposed changes to its recommendation processes to mitigate the effects of systemic racism.