eGFR Reporting for African American Patients: Race-Free Equations Are Now Standard
As of 2021, the eGFR for African American patients should be reported WITHOUT a race-based adjustment using the race-free CKD-EPI 2021 equation. 1
The Problem with Race-Based eGFR
The previous race-based equations systematically overestimated kidney function in Black patients by approximately 10-16% compared to non-Black individuals with identical age, sex, and serum creatinine levels. 2 This created profound inequities:
Delayed CKD diagnosis: Approximately 2 million Black adults in the US would be reclassified to having CKD when race is removed from the calculation. 2
Delayed transplant eligibility: Removing the race coefficient increases the number of Black adults meeting transplant referral thresholds by approximately 290,000 individuals (a 29% increase). 1, 2
Reduced access to kidney-protective medications: Fewer Black patients qualified for ACE inhibitors, ARBs, and SGLT2 inhibitors due to artificially elevated eGFR values. 2
Delayed nephrology referral: 260,000 fewer Black adults met referral thresholds when race was included in the calculation. 2
The 2021 Solution: Race-Free CKD-EPI Equations
The NKF-ASN Task Force unanimously recommended immediate implementation of the 2021 CKD-EPI creatinine equation refit without the race variable for all U.S. adults. 1 This equation:
- Does not include race in calculation or reporting 1
- Was developed in diverse populations (31.5% Black participants) 3
- Has acceptable performance characteristics 1
- Reduces differential bias between Black and non-Black individuals 1
The KDOQI Work Group supports use of the race-free 2021 CKD-EPI eGFRcr, 2021 CKD-EPI eGFRcr-cys, and 2012 CKD-EPI eGFRcys equations for adults. 1
Recommended Equations by Clinical Scenario
First-Line Testing
- Use the 2021 CKD-EPI creatinine equation (race-free) for routine eGFR estimation. 1
Confirmatory Testing
For patients at risk for or with CKD, add cystatin C measurement and use the 2021 CKD-EPI creatinine-cystatin C equation (race-free) for confirmation. 1 The combined creatinine-cystatin C equations are more accurate than creatinine alone and led to smaller differences between Black and non-Black participants. 3
Cystatin C is particularly valuable in individuals with low muscle mass, where creatinine-based eGFR is less accurate. 1
Practice Point: Race Should Be Avoided
KDIGO Practice Point 1.2.4.2 explicitly states: "Use of race in the computation of eGFR should be avoided." 1
Clinical Impact of the Change
When transitioning from race-based to race-free equations in Black patients:
eGFR values will decrease by a median of approximately 3.6-7.1 mL/min/1.73 m². 3
More Black patients will be identified as having CKD (eGFR <60 mL/min/1.73 m²), triggering earlier nephrology referral, kidney-protective medications, and transplant evaluation. 1, 2
This represents correction of previous underdiagnosis, not creation of new disease. 2, 4
Common Pitfall to Avoid
Do not report two eGFR values (one with and one without race) or label them as "high muscle mass" versus "low muscle mass." 1 The Task Force found no evidentiary basis for these approaches, which introduce subjectivity, confuse clinicians, and perpetuate the same biases. 1
Implementation Status
Clinical laboratories should implement the race-free 2021 CKD-EPI equations and report eGFR alongside filtration marker concentrations. 1 The race-free approach eliminates systematic disadvantages for Black individuals while maintaining accuracy across all populations. 1, 4