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When HbA1c Lies: Recognizing and Managing HbA1c-Glucose Discordance in Clinical Practice
1Department of Family Medicine, Mayo Clinic Health System, Red Wing, Minnesota.
Southern Medical Journal
|August 4, 2026
Summary
Hemoglobin A1c (HbA1c) and glucose measurements can differ in diabetes care. Understanding factors causing this discordance helps personalize treatment and prevent complications.
Area of Science:
- Endocrinology
- Clinical Chemistry
Background:
- Hemoglobin A1c (HbA1c) is crucial for diabetes management.
- Discordance between HbA1c and blood glucose is frequent.
- This discrepancy can lead to treatment errors and patient harm.
Purpose of the Study:
- To review factors causing HbA1c-glucose discordance.
- To provide practical strategies for managing discordant results.
- To guide clinicians in individualized diabetes care.
Main Methods:
- Literature review of biological and clinical factors.
- Development of a clinical framework for evaluating discordant data.
- Integration of laboratory testing and continuous glucose monitoring (CGM) metrics.
Main Results:
- Identified common causes: iron deficiency, CKD, RBC turnover, hemoglobin variants, glycemic changes.
- Presented a stepwise approach for discordant data evaluation.
- Highlighted the importance of avoiding automatic medication escalation.
Conclusions:
- Recognizing HbA1c-glucose discordance is vital for safe diabetes care.
- Individualized treatment based on comprehensive glucose monitoring is recommended.
- Interdisciplinary care and patient communication are key.
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