Algorithms factor in a patient's age, sex and race to adjust variables when calculating risks and test results. When it comes to race in estimated glomerular filtration rate equations — a test that measures kidney function — physicians only have two options: "Black" or "other," according to an April 27 report by CNN.
The issue with race correction in medical algorithms is that race is not a biological category, it's a social one, experts told CNN. Ancestry is biological, but the shade of a person's skin is not.
Tiger Woods is a mix of Black, white, American Indian and Asian. Yet, he is categorized as being Black to many based on the color of his skin.
"You can be half Black and half white in this country and you are Black," Carina Seah, who is getting her medical degree and a PhD in genetics and genomics at New York City-based Icahn School of Medicine at Mount Sinai, told CNN. "You can be a quarter Black in this country — if you have dark skin, you are Black."
It can be misleading and dangerous for physicians to judge a patient's ancestry by glancing at their skin. A patient who has a white mother and Black father could have a genetic mutation that typically presents itself in patients of European ancestry, but a doctor may not think to test for it if they only see Black skin, Ms. Seah said.
Studies show removing race correction from eGFR equations changes how patients at hospitals are treated.
Researchers from Boston-based Brigham and Women's Hospital and Philadelphia-based Penn Medicine estimated up to 1 in every 3 Black patients with kidney disease would have been reclassified from stage 3 to stage 4 chronic kidney disease if race wasn't factored in.
Neil Powe, MD, chief of medicine at Zuckerberg San Francisco General Hospital, worries that simply eliminating race from these equations may exacerbate health disparities instead of solve them. For too long, physicians had to fight for diversity in medical studies, he said.
The most recent eGFR equation was developed using data pooled from 26 studies, including almost 3,000 patients who self-identified as Black. Researchers found their equation was more accurate for Black patients when it was adjusted by a factor of about 1.2.
Researchers are using race as a variable because they don't know exactly what the factor is that causes increased risk for those with African descent. Yet, they think that factor is more common in Black people. Research has linked those with African ancestry with higher levels of creatinine, a waste product filtered by the kidneys.
Instead of creating a Black or other group within the eGFR equation, Dr. Powe poses the question: Why isn't everyone given the value assigned to Black people?
By ignoring the differences that researchers found, "you're taking the data on African Americans, and you're throwing it in the trash," he said.