Type of Anemia, Chronic Non-cardiovascular Illnesses, and Outcomes of Patients with ST-segment Elevation Myocardial Infarction

OBJECTIVES: To assess the impact of different types of anemia and of concomitant non-cardiovascular chronic illnesses on outcomes of patients with ST-segment elevation myocardial infarction (STEMI) and baseline anemia admitted to the Intensive Cardiac Care Unit. METHODS: Based on the mean corpuscular volume, anemia was stratified into: microcytic (<80 fL), normocytic (≥80, <96 fL), and macrocytic (≥96 fL). Data on concomitant chronic non-cardiovascular illnesses including malignancies were carefully collected. Endpoints included in-hospital bleeding as well as all-cause mortality at long-term follow-up. RESULTS: Of 1,390 patients with STEMI, 294 patients had baseline anemia (21.2%), in whom normocytic, microcytic, and macrocytic anemia was present in 77.2%, 17.0%, and 5.8% patients, respectively. In-hospital bleeding occurred in 25 (8.5%) of the study population without significant differences between the three groups. At a mean follow-up of 5.5±3.5 years, 104 patients (35.4%) had died. Mortality was the highest in patients with macrocytic anemia, followed by patients with normocytic anemia and microcytic anemia (58.8%, 37.0%, and 20.0%, respectively; P=0.009). Chronic non-cardiovascular condition was identified as an independent predictor of both in-hospital bleeding (odds ratio=2.57, P=0.01) and long-term mortality (hazard ratio [HR] 1.54, P=0.019). Performance of coronary angiography within index hospitalization was associated with lower long-term mortality (HR 0.38, P=0.001). Mean corpuscular volume did not predict either in-hospital bleeding or mortality. CONCLUSIONS: Chronic non-cardiovascular illnesses are highly prevalent among patients with STEMI and baseline anemia, and are strongly associated with higher in-hospital bleeding and long-term mortality. Type of anemia is not related to prognosis post-STEMI.