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Glycated haemoglobin A₁c for diagnosing diabetes in Chinese subjects over 50 years old: a community-based

Shuo Lin1, Li Hu, Xiaofeng Li

  • 1Department of Endocrinology, The 3rd Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.

Clinical Endocrinology
|March 16, 2013
PubMed

Insights

A glycated haemoglobin A1c (HbA1c) threshold of 48 mmol/mol (6.5%) is effective for diagnosing diabetes in Chinese adults over 50. This finding supports using HbA1c for diabetes screening in this demographic.

Area of Science:

  • Endocrinology
  • Diabetes Mellitus Research
  • Public Health

Background:

  • Glycated haemoglobin A1c (HbA1c) is a key biomarker for diabetes diagnosis.
  • Optimal HbA1c diagnostic thresholds in older Chinese populations remain under-researched.
  • Community-based screening requires validated diagnostic criteria.

Purpose of the Study:

  • To evaluate the diagnostic performance of HbA1c for diabetes in Chinese individuals over 50 years old.
  • To determine the optimal HbA1c threshold for diagnosing diabetes in this specific demographic.
  • To compare HbA1c with fasting plasma glucose (FPG) and oral glucose tolerance test (OGTT) criteria.

Main Methods:

  • A cross-sectional community survey of 1494 Chinese subjects aged over 50.
  • Measurement of fasting plasma glucose (FPG) and HbA1c.
  • Use of 1999 WHO criteria for diabetes diagnosis, with OGTT for confirmation.

Main Results:

  • An HbA1c threshold of 48 mmol/mol (6.5%) demonstrated high specificity (95.5%) and good sensitivity (75.9%) for diabetes diagnosis.
  • The area under the ROC curve for HbA1c was 0.916, compared to 0.972 for 2-h plasma glucose after OGTT.
  • Diabetes was identified in 11.9% of participants who underwent OGTT.

Conclusions:

  • An HbA1c threshold of 48 mmol/mol (6.5%) is a highly specific and sensitive marker for diagnosing diabetes in Chinese adults over 50.
  • This threshold is recommended for diabetes diagnosis in this population, aligning with community screening needs.
  • Further validation in diverse Chinese populations is warranted.
Abstract

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