Kidney health: Estimating eGFR without the inclusion of race and sex

Can you estimate Glomerular Filtration Rate (eGFR) without the inclusion of race and sex?

The European Kidney Function Consortium (EKFC) followed up on the initiative from the Chronic Kidney Disease Epidemiology Collaboration (CKD-Epi) addressing the race factor in eGFR equations in a recent study with data from over 227 000 patients. In addition, the EKFC looked at excluding sex from the equation.

Estimating the GFR without compromising on accuracy

The EKFC concluded that their newly developed cystatin C based eGFR equation that does not rely on factors for race and gender can estimate the GFR without compromising on accuracy versus creatinine equations. The EKFC also documented that an eGFR based on the average of the EKFC eGFRcys and the EKF eGFRcr (where the latter has a factor for the local population and the gender) achieves a higher accuracy for eGFR¹.

What is the reason for the heightened interest in eGFR equations?

The heightened interest stems from a movement among US medical students that questioned the use of a race coefficient in the calculation of eGFR and the downstream impact its use may have in perpetuating healthcare disparities faced by African Americans. Simply removing the race coefficient from the 2012 CDK-Epi equation was shown to introduce systematic misclassification that could not be eliminated when numerous non-GFR determinants of serum creatinine level were accounted for, according to Hsu C., et al².

For anyone looking to estimate GFR without the race factor and any issues related to gender, there is a solution and that is measuring cystatin C and applying a well-documented eGFRcys equation.

Gentian Cystatin C Immunoassay - available on most automated clinical chemistry platforms 

Gentian's cystatin C immunoassay is applied to turbidimetry-based clinical chemistry platforms. It is an open channel assay, meaning it can be added to all clinical chemistry analysers.

• FDA510(k) cleared and CE-marked
• IVDR certified
• Developed and manufactured by Gentian
• Manufactured according to ISO 13485:2016

Interested in cystatin C - Get in touch

Explore cystatin C in your clinical practice and laboratory - fill out the form or send an email to marketing@gentian.com for more information about the product and prices.

References:

1. Pottel H, Björk J, Rule AD et al. Cystatin C-Based Equation to Estimate GFR without the Inclusion of Race and Sex. N Engl J Med. 2023;388(4):333-343
2. Inker LA, Eneanya ND, Coresh J et al. New Creatinine- and Cystatin C-Based Equations to Estimate GFR without Race. N Engl J Med. 2021;385(19):1737-1749
3. Hsu CY, Yang W, Parikh RV et al. Race, Genetic Ancestry, and Estimating Kidney Function in CKD. N Engl J Med. 2021;385(19):1750-1760