Impact of diabetes on heart failure incidence in adults with ischemic heart disease.

BACKGROUND: Ischemic heart disease (IHD) is the most potent risk factor for heart failure (HF). Our study aims to evaluate the incremental impact of diabetes on the incidence of HF in individuals with IHD.

METHODS: Data from the NHANES Epidemiologic Follow-Up Study (Baseline: 1971 to 1974) were linked to the facility and mortality files up to 1992. Our analyses were restricted to patients with IHD without prevalent HF at baseline. The cumulative incidence of HF in patients with diabetes and IHD versus those with IHD alone was assessed using failure curves. Cox proportional hazards models were used to control for important covariates. All analyses incorporated the complex sample design by including the weights and clustering variables.

RESULTS: Out of the 14,407 participants, 497 had IHD without prevalent HF and had information about diabetes status. Among these participants, the cumulative incidence of HF was 38.1% for those with diabetes (n=63) and 26.5% in those without diabetes (n=434) (log-rank p-value<0.005). The multivariate hazard ratio (adjusted for age, BMI, alcohol consumption, hypertension, high cholesterol, and smoking) for incident HF for people who had myocardial infarction (MI) and diabetes compared to people who had MI alone was 2.98 (95% CI 1.51, 5.88).

CONCLUSION: Among participants with MI, those with diabetes had a substantially higher incidence of HF than those without diabetes. Based on these findings, practitioners should focus greater attention on patients with diabetes and previous MI in order to potentially prevent incident HF.