The University of Maryland Medical System is doing away with an algorithm that for decades determined the kidney health of patients. The calculations from blood tests may have stripped thousands of African American patients from getting proper timely treatments.
The medical system and the University of Maryland School of Medicine said this week that they will stop using the methodology.
“We now recognize increasingly across medicine that race is a social construct and not a biologic construct,” said University of Maryland Medical System nephrologist Dr. Stephen Seliger. “And race doesn’t have an appropriate role in these medical measurements.”
Advocates say the algorithm may have cost thousands of African American patients from getting lifesaving transplants. And, thousands of Black patients across the region could be affected by the move to drop the calculation.
“People who identify as African American are less likely to have access to kidney transplants and one possible explanation for that is a delay in referral because their kidney function is being estimated as being better than it actually is,” Seliger said.
Here’s how the algorithm works:
- Doctors draw blood from a patient’s muscles to measure creatinine, which reveals how well a person’s kidneys are cleaning the blood.
- After physicians get the results, they calculate in the patient’s race. If the patient is Black, the equation usually deemed healthier kidneys.
- For all other patients — even with the same test results, age and gender — the algorithm frequently lowered the level of kidney health, leading to a diagnosis of kidney disease.
“It was based implicitly on a belief that people of African ancestry had higher levels of muscle mass, and the blood test that we’re measuring is derived in part from skeletal muscle,” Seliger said. “It’s not really grounded in particularly any good data. It’s almost certainly a fallacy.”
Because the algorithm determined that many Black patients had better kidney health, doctors often missed early onset kidney disease, which is difficult to detect, Seliger said.
“Most people don’t have readily recognizable symptoms that will indicate its presence,” he said. “It’s therefore necessary that laboratory testing is essential for making the diagnosis.”
A nationwide social justice movement brought the issue to doctors’ attention at the National Kidney Foundation and the American Social Nephrology, two of the country’s leading medical research groups.
The groups are urging hospitals nationwide to stop using the calculation immediately.
As Seliger and his team work to remove the algorithm, he said one of the key components include educating patients and doctors.
“My advice to patients is to understand that medical knowledge evolves over time,” Seliger said. “Have an honest conversation with their providers. Moving forward we need to make sure doctors can explain to their patients why they’re re-estimating their kidney function. And, that re-estimation may lead to a reclassification of the patient.”