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Relation between hemoglobin a(1c) and outcomes in heart failure patients with and without diabetes mellitus

G Sofia Tomova1, Vani Nimbal, Tamara B Horwich

  • 1David Geffen School of Medicine at UCLA, Los Angeles, California, USA.

The American Journal of Cardiology
|March 31, 2012
PubMed

Insights

In advanced heart failure patients with diabetes mellitus, higher glycosylated hemoglobin (HbA1c) levels correlate with better survival outcomes. This association was not observed in patients without diabetes, suggesting a complex relationship in heart failure management.

Area of Science:

  • Cardiology
  • Endocrinology
  • Metabolic Diseases

Background:

  • Elevated glycosylated hemoglobin (HbA1c) increases heart failure (HF) risk in the general population.
  • The association between HbA1c and outcomes in patients with established HF is not well-established.

Purpose of the Study:

  • To investigate the relationship between HbA1c levels and clinical outcomes in patients with advanced heart failure, stratified by the presence or absence of diabetes mellitus (DM).

Main Methods:

  • A cohort of 845 advanced HF patients were stratified by DM status and HbA1c quartiles.
  • Primary outcomes included death and death or urgent heart transplantation.
  • Risk-adjusted analyses were performed to evaluate hazard ratios.

Main Results:

  • In patients with DM, higher HbA1c quartiles (Q3-Q4) were associated with significantly better 2-year event-free survival compared to lower quartiles (Q1-Q2).
  • In the DM cohort, higher HbA1c levels correlated with decreased hazard ratios for death/urgent transplantation and all-cause mortality.
  • No significant association between HbA1c quartiles and outcomes was observed in patients without DM.

Conclusions:

  • In advanced heart failure patients with diabetes, higher HbA1c levels are paradoxically associated with improved survival.
  • The observed relationship between HbA1c and outcomes in advanced HF differs between diabetic and non-diabetic patients.
  • Further research is needed to elucidate the mechanisms linking HbA1c, diabetes, and survival in advanced heart failure.

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