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Global standardisation of HbA1c

Leslie C Lai1

  • 1Gleneagles Intan Medical Centre, Kuala Lumpur, Malaysia.

The Malaysian Journal of Pathology
|March 19, 2009
PubMed

Insights

Standardizing hemoglobin A1c (HbA1c) assays is crucial for accurate diabetes management and complication risk prediction. The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) developed a global reference system for improved accuracy and comparability.

Area of Science:

  • Clinical Chemistry
  • Diabetology
  • Laboratory Medicine

Background:

  • Hemoglobin A1c (HbA1c) is vital for assessing glycemic control in diabetes patients.
  • HbA1c levels predict the risk of diabetes-related complications, as shown by the DCCT trial.
  • Standardization of HbA1c assays is essential for reliable and comparable results across laboratories.

Purpose of the Study:

  • To highlight the importance of standardizing HbA1c assays.
  • To introduce the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) global HbA1c reference system.
  • To recommend reporting HbA1c results using both IFCC and NGSP standards, along with estimated average glucose (eAG).

Main Methods:

  • Review of existing HbA1c standardization programs (NGSP, Sweden, Japan).
  • Development of a global HbA1c reference system by the IFCC Working Group.
  • Establishment of a relationship between IFCC-HbA1c, NGSP-HbA1c, and estimated average glucose (eAG).

Main Results:

  • Existing standardization programs (NGSP, Sweden, Japan) use direct comparison methods (DCMs) and yield different results.
  • The IFCC has developed a global reference system with significantly improved intra-assay and inter-assay precision.
  • A strong correlation between eAG and HbA1c has been demonstrated, supporting dual reporting.

Conclusions:

  • Standardized HbA1c measurements are critical for effective diabetes care and complication risk assessment.
  • The IFCC global reference system offers improved accuracy and consistency for HbA1c testing.
  • Reporting HbA1c in both IFCC units (mmol/mol Hb) and NGSP units (%) alongside eAG provides comprehensive glycemic information.

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