Abstract 1445: The Association of Hemoglobin A1c With Incident Heart Failure Among Persons Without Diabetes: The Atherosclerosis Risk in Communities (ARIC) Study
Introduction: While observational studies have reported that elevated hemoglobin A1c (HbA1c) levels are associated with incident heart failure (HF) in patients with diabetes mellitus, little is known about this association among persons without diabetes.
Hypothesis: Elevated HbA1c is associated with incident HF among individuals without diabetes.
Methods: We analyzed data from 10,810 participants of the ARIC Study without a history of HF or diabetes and fasting glucose <126 mg/dL. We used Cox proportional hazards models to estimate the hazard ratios (HRs) of incident HF by quartiles (Q1– 4) of HbA1c and serum glucose at baseline (1990 –92). Incident HF was defined as death or hospitalization due to HF.
Results: A total of 809 cases of incident HF developed during a median of 14 years of follow-up (incidence rate 5.6/1,000 person-years). After adjustment for covariates, the HR of incident HF was higher in Q4 compared to Q1 of HbA1c (Table⇓). In contrast, Q4 of serum glucose was not associated with incident HF. A history of coronary heart disease at baseline did not modify the association between HbA1c and HF risk (P=0.87). Exclusion of participants with HbA1c ≥6.5%, on diuretics, angiotensin-converting enzyme inhibitors, or beta-blockers, or who developed diabetes in the first 6 years of follow-up did not substantially alter the results. When we categorized participants into the following categories of HbA1c: <5.0, 5.0 –5.4, 5.5– 6.0, 6.0 – 6.4%, and ≥6.5%, an association between HbA1c and HF was observed only at levels > 6.0%: HR 1.43 [95% CI, 0.99 to 2.05] for HbA1c 6.0 – 6.4% and 2.55 [1.54 to 4.21] for HbA1c ≥6.5% as compared to HbA1c <5.0%.
Conclusion: Elevated HbA1c but not fasting glucose was associated with increased risk of HF in a middle-aged bi-ethnic population without diabetes. Our findings suggest that impaired glucose homeostasis may be an independent risk factor for the development of HF and HbA1c may be a better biomarker to evaluate the risk of HF as compared to glucose.