Estimated Average Glucose (eAG)
Understanding Estimated Average Glucose
Estimated Average Glucose (eAG) is a way to translate your HbA1c results into the same units you see on your daily blood glucose meter. This makes it easier to understand how your average blood glucose levels relate to your HbA1c test results.
What is Estimated Average Glucose?
eAG provides an estimate of your average blood glucose over the past 2-3 months, calculated from your HbA1c value using the formula:
eAG (mg/dL) = 28.7 × HbA1c - 46.7
While HbA1c is reported as a percentage or in mmol/mol, eAG is expressed in the same units as your daily blood glucose readings (mg/dL or mmol/L), making it more relatable to daily self-monitoring.
Normal Values
For people without diabetes:
- HbA1c: 4% to 5.6% (20-37 mmol/mol)
- eAG: 97-126 mg/dL (5.4-7.0 mmol/L)
Target ranges for people with diabetes (individualized based on various factors):
- HbA1c: Generally < 7.0% (53 mmol/mol)
- eAG: < 154 mg/dL (8.6 mmol/L)
Clinical Significance
Uses
- Monitoring long-term blood glucose control
- Setting and adjusting diabetes treatment goals
- Improving patient understanding of glucose control
- Correlating HbA1c with daily glucose measurements
Benefits
- Better understanding of glucose control
- Easier comparison with daily readings
- Improved communication between healthcare providers and patients
- More meaningful goal setting
Important Considerations
- Individual variations may exist
- Results are estimates based on population studies
- Should be used alongside other monitoring tools
- Regular monitoring is essential for diabetes management
When to Check HbA1c/eAG
For people with diabetes:
- Every 3 months if not meeting treatment goals
- Every 6 months if meeting treatment goals
- More frequently if treatment changes
Limitations
This calculator:
- Is based on research from the A1c-Derived Average Glucose (ADAG) study
- May not apply to children, pregnant women, or people with certain blood conditions
- Shows the typical relationship between HbA1c and average glucose, but individual results may vary
- Should be used as part of comprehensive diabetes care
- Cannot replace regular blood glucose monitoring
Tips for Accurate Results
- Use recent HbA1c values
- Ensure correct units are selected
- Consider factors that may affect HbA1c accuracy
- Discuss results with healthcare provider
Factors Affecting HbA1c/eAG
- Anemia
- Hemoglobin variants
- Recent blood loss or transfusion
- Certain medications
- Pregnancy
- Kidney disease
Clinical Applications
eAG is particularly useful for:
- Patient education
- Treatment goal setting
- Monitoring diabetes control
- Adjusting diabetes management plans
Start calculating now to better understand your blood glucose control!
References: