Usefulness of Anemia in Men as an Independent Predictor of Two-Year Cardiovascular Outcome in Patients Presenting With Acute Coronary Syndrome

Anemia has been shown to be an independent risk factor for the development of adverse cardiovascular outcomes in a variety of patient populations. In the case of patients presenting with acute coronary syndrome (ACS), anemia has been demonstrated to be a powerful and independent predictor of 30-day outcomes. However, there are limited and conflicting data about the long-term independent predictive value of anemia in patients with ACS. This is in contrast to non-ACS populations in which anemia has been shown to be an independent predictor of long-term outcomes. The present study investigated the long-term prognostic significance of anemia in a well-characterized cohort of 193 men with ACS who were referred for coronary angiography at a Veterans Affairs Medical Center. All patients were followed prospectively for the development of death or acute myocardial infarction (AMI), and follow-up data were available for all patients at 24 months. After controlling for a variety of baseline clinical, laboratory, and angiographic variables, hemoglobin (analyzed as a continuous variable and as a categorical variable using the World Health Organization cutoff of 13 g/dl for men) was a strong and independent predictor of the composite end point of death or AMI at 24 months when using a Cox proportional hazards model. At 24 months, the event-free survival was 64% in the group with a hemoglobin level <13 g/dl compared with 81% in the group with a hemoglobin level ≥13 g/dl (p = 0.0065 by log-rank test). In conclusion, these data demonstrate that baseline anemia is a strong and independent predictor of death or AMI at 2 years in patients with ACS.