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HbA1c as a Diagnostic Test for Diabetes Mellitus - Reviewing the Evidence

Chris Florkowski1

  • 1Canterbury Health Laboratories, PO Box 151, Christchurch, New Zealand.

The Clinical Biochemist. Reviews
|October 24, 2013
PubMed

Insights

Hemoglobin A1c (HbA1c) is a reliable diagnostic test for diabetes mellitus, primarily used to predict long-term microvascular complications. Its effectiveness supports global adoption for diabetes diagnosis, despite minor variations in testing strategies.

Area of Science:

  • Clinical Biochemistry
  • Endocrinology
  • Diagnostic Medicine

Background:

  • The Stockholm Hierarchy emphasizes clinical outcomes for validating diagnostic tests.
  • Microvascular complications are a key concern in diabetes mellitus management.
  • Hemoglobin A1c (HbA1c) has emerged as a significant biomarker.

Purpose of the Study:

  • To review the evidence supporting HbA1c as a diagnostic tool for diabetes mellitus.
  • To highlight the role of HbA1c in predicting clinical outcomes, specifically microvascular complications.
  • To discuss the global adoption and variations in HbA1c testing strategies for diabetes diagnosis.

Main Methods:

  • Evidence-based review focusing on clinical outcomes.
  • Analysis of data related to microvascular complications in diabetes.
  • Examination of international guidelines and testing strategies for HbA1c.

Main Results:

  • The evidence supporting HbA1c is strongly linked to predicting clinical outcomes, particularly long-term microvascular complications.
  • A substantial body of data validates HbA1c's utility in diabetes diagnosis.
  • HbA1c is endorsed for diabetes diagnosis in numerous countries, with some differences in cut-offs and methodologies.

Conclusions:

  • HbA1c is a well-established and validated diagnostic test for diabetes mellitus.
  • Its ability to predict microvascular complications underpins its widespread acceptance.
  • International consensus supports HbA1c use, though localized adaptations in testing exist.

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