What is the normal estimated glomerular filtration rate (eGFR) range for a healthy adult, including Black women, and is any race adjustment required when using the current race‑free CKD‑EPI creatinine equation?

Normal eGFR Range in Adults

The normal estimated glomerular filtration rate (eGFR) for healthy adults is ≥90 mL/min/1.73 m², and all current calculations should use the race-free 2021 CKD-EPI creatinine equation without any race adjustment for all patients, including Black women. 1, 2, 3

Standard Normal Range

• eGFR ≥90 mL/min/1.73 m² represents normal kidney function in healthy adults across all racial and ethnic groups. 1, 2
• Values between 60-89 mL/min/1.73 m² may be normal in older adults or represent mild reduction in kidney function, depending on the presence of other markers of kidney damage. 2
• eGFR <60 mL/min/1.73 m² for ≥3 months defines chronic kidney disease when accompanied by evidence of kidney damage. 2, 3

Current Calculation Standard: Race-Free Equation

The 2021 CKD-EPI creatinine equation without race is now the mandatory standard for all U.S. adults. 1, 2, 3

Key Implementation Points

• No race adjustment is required or recommended when using the current 2021 CKD-EPI equation—the race coefficient has been completely removed from both calculation and reporting. 1, 3
• The equation uses only serum creatinine (calibrated to IDMS), age, and sex. 2
• This single equation applies uniformly to all patients, including Black women, eliminating the previous practice of applying a race multiplier. 1, 3

Why Race Was Removed

• The prior race-based equations systematically overestimated kidney function in Black patients by approximately 10-16%, delaying diagnosis of CKD, nephrology referrals, transplant eligibility, and initiation of kidney-protective medications. 1
• Removing the race coefficient increases identification of Black adults with eGFR <60 mL/min/1.73 m² and improves equitable access to kidney transplant evaluation (increasing eligible Black adults by approximately 290,000, a 29% increase). 1, 4
• The 2022 NKF-ASN Task Force issued a strong recommendation to eliminate race from eGFR calculations to reduce differential bias between Black and non-Black individuals while maintaining acceptable accuracy. 5, 1, 3

Confirmatory Testing Strategy

For patients at risk for or with established CKD, add cystatin C measurement and use the 2021 CKD-EPI creatinine-cystatin C equation (also race-free) for confirmation. 1, 2, 3

When to Add Cystatin C

• Extremes of muscle mass (very high or very low). 2, 3
• eGFR 45-59 mL/min/1.73 m² without other markers of kidney damage. 2
• Advanced cirrhosis or cancer. 2
• Critical clinical decisions requiring high precision (transplant evaluation, chemotherapy dosing, nephrotoxic drug initiation). 1, 2
• The combined creatinine-cystatin C equation provides greater accuracy than either marker alone and fully eliminates any need for race-based adjustments. 1, 3

Special Considerations for Black Women

Black women should receive eGFR calculated with the race-free 2021 CKD-EPI equation, with particular attention to body habitus. 1

Obesity and Medication Dosing

• Obesity prevalence is highest in Black women, and indexed eGFR values (mL/min/1.73 m²) systematically underestimate true GFR in obese patients. 1
• For medication dosing decisions, use non-indexed eGFR values (mL/min) rather than indexed values, especially in obese patients. 1, 3
• De-indexing GFR for medication dosing is strongly advised in obese Black women to avoid therapeutic under-dosing from underestimated kidney function. 1

Laboratory Reporting Standards

• Laboratories should automatically report eGFR using the race-free 2021 CKD-EPI equation whenever serum creatinine is ordered. 2, 3
• Display serum creatinine values to two decimal places (for values <1 mg/dL) to improve precision. 1
• Do not report two eGFR values (one with race and one without) or label them as "high muscle mass" versus "low muscle mass"—the Task Force found no evidentiary basis for dual reporting, which adds subjectivity and confusion. 1
• Report both the eGFR value and the corresponding serum creatinine concentration. 1

Clinical Decision-Making Principles

• Do not base major clinical decisions on a single eGFR result; confirm with repeat testing and monitor trends over time. 1, 2
• Incorporate albuminuria assessment to complement eGFR information, as recommended by KDIGO CKD guidelines. 1
• For critical decisions requiring high precision, consider direct GFR measurement using exogenous filtration markers (iohexol or radioisotopic tracers). 1, 2

Common Pitfalls to Avoid

• Never use serum creatinine alone to assess kidney function—always calculate eGFR. 2
• Do not apply the old race multiplier (×1.159 for Black patients) to the 2021 equation—it is already race-free. 1, 3
• Ignoring body habitus when interpreting indexed eGFR in obese patients leads to underestimation of true kidney function and potential medication errors. 1
• Avoid using outdated equations (MDRD, Cockcroft-Gault with race, or 2009 CKD-EPI with race) for current clinical decisions. 2, 3