Association Between Iron Deficiency and Poor Prognosis Acute Coronary Syndrome : A Systematic Review and Metaanalysis Studies

Abstract

Introduction: Acute Coronary Syndrome (ACS) is a leading cause of global morbidity and mortality. Iron deficiency (ID), a common condition in ACS patients, is increasingly recognized as a potential factor for a poor prognosis. This systematic review and meta-analysis aims to synthesize the existing evidence on the association between ID and prognosis following an ACS event.

Methods: Following PRISMA 2020 guidelines , a systematic search was conducted in PubMed, Semantic Scholar, Springer, and Google Scholar. We included observational studies and randomized controlled trials that evaluated ID and clinical outcomes in adult ACS patients. After screening, 26 studies were included in the final analysis.

Results: The meta-analysis of short-term outcomes showed no statistically significant increase in risk. However, for long-term prognosis, the analysis of six studies revealed that ID was significantly associated with a poorer prognosis. The summarized hazard ratio (HR) was 1.49 (95% Confidence Interval: 1.17 - 1.90), indicating a 49% increased risk of adverse outcomes. Furthermore, prospective observational studies reported that correcting ID was associated with significant improvements in left ventricular ejection fraction, cardiac remodeling, and quality of life.

Conclusion: Iron deficiency are significant predictors of adverse long-term outcomes in patients after ACS. While correcting ID appears to improve surrogate endpoints like cardiac function and quality of life, the current literature is limited by heterogeneous definitions of ID. There is an urgent need for large-scale randomized controlled trials using standardized criteria to determine if treating ID reduces hard clinical endpoints, such as mortality and major adverse cardiovascular events (MACE).