Relation Between Hemoglobin A1c and Outcomes in Heart Failure Patients With and Without Diabetes Mellitus
The American Journal of Cardiology, 06/07/2012
Tomova GS et al. – In this cohort of patients with advanced heart failure (HF), higher HbA1c levels were associated with improved outcomes in patients with diabetes mellitus (DM). This relation was not observed in patients without DM. Further investigations into mechanisms underlying the relation between HbA1c, DM, and survival in advanced HF are warranted.Methods
- A total of 845 patients with advanced HF followed at the Ahmanson–UCLA Cardiomyopathy Center were studied, stratified by the presence (n = 358) or absence (n = 487) of DM and by DM–specific HbA1c quartiles (patients with DM: Q1 ≤6.4%, Q2 6.5% to 7.2%, Q3 7.3% to 8.5%, and Q4 ≥8.6%; patients without DM: Q1 ≤5.6%, Q2 5.7% to 6.0%, Q3 6.1% to 6.5%, and Q4 ≥6.6%).
- The primary outcomes analyzed were death and death or urgent heart transplantation.
- In the cohort with DM, 2–year event–free survival was 61% and 65% in Q3 and Q4 compared to 48% and 42% in Q1 and Q2 (p = 0.005).
- In the cohort without DM, there was no difference in outcomes by HbA1c quartile.
- Risk–adjusted analysis in the diabetic cohort showed significantly increased hazard ratios for death or urgent heart transplantation in Q1 and Q2 compared to Q4.
- For every unit HbA1c increase, there was a 15% decreased hazard ratio of death or urgent heart transplantation and all–cause mortality (p = 0.006 and p = 0.036, respectively).
- In the cohort without DM, multivariate models revealed similar hazard ratios among HbA1c quartiles.