In collaboration with the National Kidney Foundation (NKF), the Association for Diagnostics & Laboratory Medicine (ADLM, formerly AACC) released a guidance document to reduce racial and gender disparities in chronic kidney disease (CKD) patient care. The document shares evidence-based tools and strategies to improve equity and inclusivity in kidney health.
In 2021, the NKF and the American Society of Nephrology recommended new equations for determining the estimated glomerular filtration rate (eGFR). Previously, eGFR was calculated using an adjustment coefficient for Black patients because people who described themselves as African American were found to have higher blood levels of creatinine than other racial groups. However, the new equations mentioned in the ADLM/NKF guidance don’t include this coefficient.
The guidance also recommends incorporating levels of cystatin C, a blood biomarker that is filtered through the glomerular membrane, into eGFR equations. Because cystatin C has far fewer non-GFR determinants than creatinine, it a more stable and, therefore, offers enhanced accuracy in eGFR calculations.
Biases in gender-diverse patients
The eGFR equations include a variable to account for the patient’s sex. However, applying a binary sex variable to transgender patients may be inaccurate, because gender-affirming hormones can cause changes in muscle mass and fat distribution that affect creatinine levels. For gender-diverse patients, the guidance suggests calculating eGFR using both male and female values and taking an inclusive, holistic approach to disease management.
“Race and ethnicity are imprecise, nebulously defined systems of classification as they pertain to genetic ancestry, physiological characteristics, and socioeconomic status, and therefore should not be used to classify individuals into distinct biological categories,” said lead authors Christina C. Pierre, PhD, DABCC, FAACC, and Mark A. Marzinke, PhD, in a recent press release.