Acute
myocardial infarction remains a leading cause of morbidity and mortality. While
iron deficient
heart failure patients are at increased risk of future cardiovascular events and see improvement with intravenous supplementation, the clinical relevance of
iron deficiency in
acute coronary syndrome remains unclear. We aimed to evaluate the prognostic value of
iron deficiency in the
acute coronary syndrome (ACS). Levels of
ferritin,
iron, and
transferrin were measured at baseline in 836 patients with ACS. A total of 29.1% was categorized as
iron deficient. The prevalence of
iron deficiency was clearly higher in women (42.8%), and in patients with
anemia (42.5%). During a median follow-up of 4.0 years, 111 subjects (13.3%) experienced non-fatal
myocardial infarction (MI) and cardiovascular mortality as combined endpoint.
Iron deficiency strongly predicted non-fatal MI and cardiovascular mortality with a hazard ratio (HR) of 1.52 (95% confidence interval (CI) 1.03-2.26; p = 0.037) adjusted for age, sex,
hypertension, smoking status, diabetes,
hyperlipidemia, body-mass-index (BMI) This association remained significant (HR 1.73 (95% CI 1.07⁻2.81; p = 0.026)) after an additional adjustment for surrogates of cardiac function and
heart failure severity (N-terminal pro
B-type natriuretic peptide,
NT-proBNP), for the size of myocardial
necrosis (
troponin), and for
anemia (
hemoglobin). Survival analyses for cardiovascular mortality and MI provided further evidence for the prognostic relevance of
iron deficiency (HR 1.50 (95% CI 1.02⁻2.20)). Our data showed that
iron deficiency is strongly associated with adverse outcome in
acute coronary syndrome.