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Low HbA1c and mortality: causation and confounding

M K Rutter1

  • 1Cardiovascular Research Group, School of Biomedicine, University of Manchester, Core Technology Facility, 46 Grafton Street, Manchester M13 9NT, UK. Martin.Rutter@manchester.ac.uk

Diabetologia
|July 19, 2012
PubMed

Insights

Low or lowered hemoglobin A1c (HbA1c) levels are linked to increased mortality in both general and diabetic populations. This commentary explores this association and its modification by body mass index (BMI) in type 2 diabetes.

Area of Science:

  • Endocrinology
  • Epidemiology
  • Cardiovascular Medicine

Background:

  • Observational studies and clinical trials indicate a link between low or lowered hemoglobin A1c (HbA1c) and increased total and cardiovascular disease (CVD) mortality.
  • This association is observed in the general population and specifically in patients with diabetes.

Purpose of the Study:

  • To provide an overview of the clinically significant data connecting low HbA1c levels to increased mortality.
  • To frame the interpretation of epidemiological data regarding HbA1c and mortality.
  • To discuss the clinical implications and highlight future research directions.

Main Methods:

  • Review and synthesis of existing epidemiological data from observational studies and clinical trials.
  • Analysis of the relationship between HbA1c levels and mortality outcomes.
  • Consideration of potential modifying factors, such as body mass index (BMI).

Main Results:

  • Evidence suggests that both low and lowered HbA1c levels are associated with elevated total and CVD mortality.
  • The commentary sets the context for research suggesting BMI may modify the HbA1c-mortality relationship in type 2 diabetes.

Conclusions:

  • The relationship between HbA1c levels and mortality is complex and warrants careful interpretation.
  • Understanding the influence of factors like BMI is crucial for clinical practice in diabetes management.
  • Further research is needed to fully elucidate these associations and their clinical implications.

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