Iron Deficiency Prevalent in Acute Coronary Syndrome, Study Finds

A new investigation found iron deficiency highly prevalent in patients with acute coronary syndrome (ACS), with more than half of patients affected, despite a notable lack of reported data in the available literature.1

This single-center, retrospective longitudinal analysis, involving all patients admitted to a coronary care unit or cardiology ward with a diagnosis of ACS, found the presence of concomitant anemia was linked to the occurrence of all-cause death.

“Our study shows that iron deficiency is prevalent in this population, affecting almost half of the patients with ACS,” wrote the investigative team, led by Rua Camilo Castelo Branco, department of cardiology, São Bernardo Hospital, Setúbal Hospital Centre. “Anemia seems to have a greater impact on mortality in the setting of an ACS.”

Nearly one-third of the global population is affected by iron deficiency, particularly children, elderly people, and premenopausal women.2 Iron deficiency is frequent in patients with cardiovascular disease, reaching up to 55% of patients with chronic heart failure and potentially up to 80% of those with acute heart failure.3

Heart failure guidelines, including those from the European Society of Cardiology (ESC), recommend the screening of iron deficiency in all patients with heart failure using serum ferritin and transferrin saturation (TSAT). However, there are limited reports on the impact of iron deficiency in a population with ACS, despite emerging data suggesting a prevalent connection.

Investigators in this analysis sought to measure iron deficiency prevalence in a population with ACS and its prognostic impact during a follow-up period.1 The study population consisted of all patients admitted to a coronary care unit with a diagnosis of ACS between January and December 2019.

Those with ST-elevation myocardial infarction (STEMI), non-ST-elevation MI (NSTEMI), and unstable angina (UA), defined by current ESC guidelines, met the criteria for inclusion. The population was separated into groups based on iron deficiency status and multiple variables, including demographics, index hospitalization, comorbidities, and echocardiographics.

For this analysis, Branco and colleagues measured each cohort’s predictive value based on the occurrence of hemorrhage or need for red blood cell (RBC) transfusion, all-cause hospitalizations, and all-cause death. At the baseline, 287 patients were included—the median age was 66 years and 72% were male, with iron deficiency present in nearly half (48%).

Most of the population presented with STEMI (57%), while 13% were admitted in Killip–Kimball (KK) class III or IV. Nearly 40% had a left ventricular ejection fraction (LVEF) <50% on study admission. Compared with STEMI, those with NSTEMI presented more frequently with iron deficiency.

Approximately one-third (33%) of patients with iron deficiency experienced concomitant anemia. Across a median follow-up of 28 months, 29 patients (10%) had an urgent care admission for HF, 20 (7%) were hospitalized for heart failure, and 51 (18%) died.

Branco and colleagues identified a significantly higher rate of emergency department admissions for HF, particularly in those with iron deficiency (15% vs. 7%). The team found no differences in the rates of ACS, stroke, all-cause hospitalization, or mortality.

Notably, investigators found age, the presence of anemia, and NT-proBNP levels were the only variables to predict the occurrence of all-cause death, with iron deficiency exhibiting a lack of impact on any of the evaluated events.

“Further studies with larger numbers are required for more definite conclusions, to evaluate the impact of functional/absolute iron deficiency, with or without anemia, on promoting heart failure (HF), and to investigate the potential prognostic role of iron supplementation in patients with ACS and iron deficiency,” they wrote.

References

1. Esteves AF, Gonçalves S, Duarte T, et al. Iron deficiency in acute coronary syndromes: prevalence and prognostic impact. Porto Biomed J. 2025;10(1):278. Published 2025 Jan 8. doi:10.1097/j.pbj.0000000000000278
2. von Haehling S, Ebner N, Evertz R, Ponikowski P, Anker SD. Iron Deficiency in Heart Failure: An Overview. JACC Heart Fail. 2019;7(1):36-46. doi:10.1016/j.jchf.2018.07.015
3. Authors/Task Force Members:, McDonagh TA, Metra M, et al. 2023 Focused Update of the 2021 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure: Developed by the task force for the diagnosis and treatment of acute and chronic heart failure of the European Society of Cardiology (ESC) With the special contribution of the Heart Failure Association (HFA) of the ESC. Eur J Heart Fail. 2024;26(1):5-17. doi:10.1002/ejhf.3024