Biomarker · Kidney
Estimated glomerular filtration rate (eGFR)
eGFR estimates how well your kidneys filter blood. Learn what the number means, how it's calculated and when a low result matters.
Written by LON6EVITY Editorial Team · Last updated
Overview
eGFR is a calculated estimate of how much blood the kidneys filter per minute, based mainly on blood creatinine, age and sex.
Why it matters
The National Kidney Foundation explains that eGFR is used to detect and stage chronic kidney disease. Early kidney disease usually has no symptoms, so testing matters for people at risk, such as those with diabetes, high blood pressure or a family history.
Lower results
A single low eGFR can be caused by dehydration or other temporary factors. Chronic kidney disease is generally considered when eGFR stays below 60 for three months or more, or when there are other signs of kidney damage.
How the test is performed
Calculated automatically by the lab from a creatinine blood test.
Reference ranges
| NKF: normal or high | ≥ 90 mL/min/1.73m² |
|---|---|
| NKF: possible chronic kidney disease if persistent ≥ 3 months | < 60 mL/min/1.73m² |
Reference ranges and targets differ between laboratories, units and guidelines, and depend on age, sex, method and your overall clinical picture. A single result is not a diagnosis — interpret it with a qualified clinician.
Factors that can affect the result
- Muscle mass
- Hydration
- Age
- Medications
- Acute illness
Questions people commonly ask
- Does eGFR fall with age?
- Kidney function tends to decline gradually with age. Your clinician interprets eGFR in that context.
Related biomarkers
Related tests
Related topics
Understand your biomarkers in context
What does this mean for your own health data? Log your results, follow trends over time and bring an organised summary to your next doctor's appointment.
Sources
- Glomerular Filtration Rate (GFR) Test. MedlinePlus, U.S. National Library of Medicine.
- Estimated Glomerular Filtration Rate (eGFR). National Kidney Foundation.