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Hemoglobin A1c: past, present and future

Saleh A Aldasouqi1, Ved V Gossain

  • 1Department of Medicine, College of Human Medicine, Michigan State University, East Lansing, Michigan, USA. saldasouqi@pol.net

Annals of Saudi Medicine
|November 18, 2008
PubMed

Insights

Hemoglobin A1c (HbA1c) monitoring shows promise for diabetes diagnosis. Recent developments suggest HbA1c may soon play a role in future global diagnostic guidelines.

Area of Science:

  • Clinical Chemistry
  • Endocrinology
  • Diabetes Mellitus Research

Background:

  • Hemoglobin A1c (HbA1c) is a long-established marker for monitoring glycemic control in diabetes.
  • Current diabetes screening and diagnosis primarily rely on plasma glucose measurements, which have limitations.

Purpose of the Study:

  • To review recent advancements in HbA1c testing and its potential diagnostic applications.
  • To evaluate the evolving role of HbA1c in diabetes screening and diagnosis.

Main Methods:

  • Review of recent literature on HbA1c methodologies and diagnostic capabilities.
  • Analysis of proposed changes for HbA1c standardization, including revised reference ranges and units.
  • Comparison of HbA1c's diagnostic potential against current plasma glucose-based guidelines.

Main Results:

  • Standardization efforts suggest lower HbA1c reference ranges and revised units (e.g., %, mg/dL, mmol/mol).
  • Existing plasma glucose diagnostic methods have shortcomings, highlighting a need for alternative approaches.
  • Emerging evidence supports HbA1c's diagnostic accuracy.

Conclusions:

  • Despite ongoing reassessment and developments, HbA1c is not currently recommended for diabetes diagnosis.
  • Future practice guidelines may consider a diagnostic role for HbA1c, supported by recent literature and expert recommendations.
  • The US Endocrine Society recently proposed initial recommendations for HbA1c's diagnostic use.

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