Removing race-based kidney function adjustment may be damaging for black cancer patients

Research from the University of Pittsburgh shows that ignoring race when calculating kidney function before starting cancer treatments could lead to the unnecessary exclusion of black patients.

The team, led by Thomas Nolin, associate professor of pharmacy and therapeutics at Pitt’s School of Pharmacy, performed the assessment because of the need to add race to the equation of chronic kidney disease-epidemiology (CKD -EPI) to calculate the function was recently questioned.

Estimated glomerular filtration rate (eGFR), a measure of kidney function, is known to vary to different degrees depending on a person’s ethnicity. Generally, black patients are known to have about 16% higher eGFR for a given serum creatinine concentration, gender and age, compared to white patients.

This is important for cancer patients because the result of the CKD-EPI equation is used to calculate eligibility for a variety of different cancer drugs. By excluding race from the equation, Nolin and his team found that many black patients would have a lower eGFR score and therefore be less likely to receive cancer treatment. As cancer rates are higher in the black population than in the white population, it could simply exacerbate current health disparities.

“Ultimately, we hope our results raise awareness of the problem, and we urge physicians to use appropriate clinical judgment and to think logically about balancing the risks and benefits of cancer drugs in the context of kidney function. of the patient, ”Nolin said in a press release. declaration.

Researchers performed a retrospective analysis of National Cancer Institute Phase I clinical trial participants enrolled in the trials between 1995 and 2010. Overall, data from 340 black patients (172 males and 168 females) were included in the study. the study, which is published in the journal The Lancet: Oncology. When the CKD-EPI equation was used with and without an adjustment for race, the researchers found that up to 18% of the cohort would have had different treatment recommendations if race had been excluded.

For example, the number of black people ineligible to receive a chemotherapy drug called cisplatin or bleomycin increased by 72% and 163%, respectively, if race was not taken into account.

“This finding underscores the critical impact that the choice of the GFR estimation equation, including whether or not to include race in the calculation, has on the eligibility and dosage of the drug in black patients with the condition. cancer, ”the authors write.

“Black patients have disparities in cancer incidence and mortality, and are therefore particularly susceptible to undertreating the disease. Removing race from the GFR estimation equations could lead to higher rates of anti-cancer drug exclusion, dose reduction, and disease undertreatment in black cancer patients, and thus could negatively affect survival results.

A recent joint task force established by the National Kidney Foundation and the American Society of Nephrology proposed replacing eGFR equations that include race with other options that do not preclude race from being used as a biological determinant of disease.

Alternative equations excluding race have been developed, but not yet deployed, and it is not known when they could be widely used.

“This study underscores the need for careful clinical judgment and a patient-centered approach to interpret and compare estimates of renal function from different GFR estimation equations, including a deep understanding of the limitations of each equation, especially when selecting and dosing anticancer drugs with a narrow therapeutic index, ”the team concludes.