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Association between HbA1c and cardiovascular disease mortality in older Hong Kong Chinese with diabetes

L Xu1, W M Chan, Y F Hui

  • 1Department of Community Medicine and School of Public Health, University of Hong Kong, Hong Kong, China.

Diabetic Medicine : a Journal of the British Diabetic Association
|September 16, 2011
PubMed

Insights

High HbA1c levels in older adults with diabetes are linked to increased mortality from all causes, cardiovascular disease, coronary heart disease, and stroke. Further research is needed to understand if low HbA1c also impacts mortality in this population.

Area of Science:

  • Gerontology
  • Endocrinology
  • Epidemiology

Background:

  • Diabetes mellitus is a chronic condition affecting millions globally, particularly older adults.
  • Glycemic control, measured by HbA1c, is crucial for managing diabetes complications.
  • Understanding the relationship between HbA1c levels and mortality risk in elderly populations is vital for public health strategies.

Purpose of the Study:

  • To investigate the association between baseline HbA1c levels and mortality from all causes, cardiovascular disease, coronary heart disease, and stroke.
  • To determine if different HbA1c ranges predict varying mortality risks in older Chinese adults with diabetes.

Main Methods:

  • A cohort of 2137 Chinese adults aged 65+ with diagnosed diabetes was followed for up to 11 years.
  • HbA1c levels were measured between 1998-2000, with data on lifestyle and medical history collected.
  • Cox proportional hazards models were used to calculate adjusted hazard ratios and 95% confidence intervals for mortality outcomes.

Main Results:

  • Higher HbA1c levels (≥69 mmol/mol) were associated with increased risk of cardiovascular disease and stroke mortality compared to HbA1c of 58-68 mmol/mol.
  • Elevated HbA1c also increased all-cause and coronary heart disease mortality risk compared to HbA1c ≤48 mmol/mol.
  • A U-shaped association was observed for stroke mortality, with both very low and high HbA1c levels potentially increasing risk.

Conclusions:

  • Elevated HbA1c is a significant predictor of increased all-cause, cardiovascular, coronary heart disease, and stroke mortality in older adults with diabetes.
  • The potential for low HbA1c levels to also increase mortality in this demographic warrants further investigation.
Abstract

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