Effect of Anemia in High-Risk Groups of Patients With Acute Myocardial Infarction Treated With Percutaneous Coronary Intervention

The significance of anemia in patients with acute myocardial infarction (AMI) treated with percutaneous coronary intervention (PCI) remains controversial. The aim of the present study was to evaluate the effect of anemia on the short- and long-term prognosis of patients with AMI treated with PCI, including high-risk subgroups. The study group consisted of 1,497 consecutive patients with AMI treated in the acute phase with PCI. Anemia was defined using World Health Organization criteria (hemoglobin level <13 g/dl for men and <12 g/dl for women). The study population was divided into 2 major groups (patients with [n = 248, 16.6%] and without [n = 1,249, 83.4%] anemia) and 6 subgroups (diabetes mellitus, impaired renal function, age >70 years, left ventricular dysfunction, incomplete revascularization, and multivessel disease). A comparative analysis was performed between both groups within the whole population and within the particular subgroups. Significantly greater 30-day (13.2% vs 7.3%), 1-year (20.5% vs 11.3%), and total (24.1% vs 12.7%; all p <0.05) mortality rates were observed in the anemic group. Multivariate analysis identified anemia as an independent predictor of any-cause death in the whole population during the observation period (covariate-adjusted hazard ratio 1.46, 95% confidence interval 1.31 to 1.61, p <0.05). Anemia was significantly associated with excessive long-term mortality in the multivessel disease group (adjusted hazard ratio 1.54, 95% confidence interval 1.34 to 1.74) and in the incomplete revascularization group (hazard ratio 1.67, both p <0.05). In conclusion, anemia on admission in patients with AMI treated in the acute phase with PCI was independently associated with increasing short- and long-term mortality, especially in the subgroups with incomplete revascularization and multivessel disease.