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Published on: June 11, 2012

Frequency of HbA1c discordance in estimating blood glucose control

Robert M Cohen1, Eric P Smith

  • 1Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267-0547, USA. robert.cohen@uc.edu

Current Opinion in Clinical Nutrition and Metabolic Care
|June 11, 2008
PubMed

Insights

Glycated hemoglobin (HbA1c) is crucial for diabetes management, but interpretation challenges exist. New research highlights factors like erythrocyte lifespan that can affect HbA1c accuracy, necessitating a nuanced approach to glycemic control assessment.

Area of Science:

  • Endocrinology
  • Clinical Chemistry
  • Diabetes Mellitus Research

Background:

  • Glycated hemoglobin (HbA1c) is a standard biomarker for assessing long-term glycemic control in diabetes.
  • Emerging evidence suggests potential discrepancies between HbA1c and other glycemia measures, complicating interpretation.
  • Clinicians must be aware of factors influencing HbA1c accuracy for optimal patient care.

Purpose of the Study:

  • To explore emerging issues that complicate the interpretation of HbA1c values.
  • To characterize discordances between HbA1c and other glycemia measures.
  • To inform clinical practice regarding HbA1c interpretation in diabetes management.

Main Methods:

  • Development of the 'glycation gap' concept to compare intracellular (HbA1c) and extracellular (fructosamine) protein glycation.
  • Analysis of physiological variables, such as erythrocyte lifespan, in relation to HbA1c discordance.
  • Review of factors affecting hemoglobin glycation, HbA1c-glycemia relationships, assay standardization, and complication risk.

Main Results:

  • Evidence indicates mismatches between HbA1c and other glycemia measures, requiring cautious interpretation.
  • Physiological variables, including erythrocyte lifespan in hematologically normal individuals, can explain discordant HbA1c results.
  • Factors influencing hemoglobin glycation and assay standardization impact HbA1c accuracy.

Conclusions:

  • Standard interpretation norms for HbA1c may need modification in various clinical scenarios.
  • Understanding factors causing discordance is crucial for accurate glycemic control assessment and complication risk prediction.
  • Nuances in HbA1c interpretation are increasingly important for effective diabetes care.
Abstract

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