Anemia in ST-Elevation Myocardial Infarction Patients with Markers of Inadequate Bone Marrow Response.

ABSTRACT

BACKGROUND: Anemia confers an adverse prognosis in patients with ST-elevation myocardial infarction (STEMI). Several mechanisms have been implicated in the etiology of anemia in this setting, including inflammation, blood loss, and the presence of comorbidities such as renal failure. OBJECTIVES: To evaluate the adequacy of bone marrow response as potentially reflected by elevation in blood and reticulocyte counts. METHODS: Consecutive men with STEMI who underwent primary percutaneous intervention within 6 hours of symptom onset and who presented to our catheterization laboratory during a 36 month period were included in the study. The cohort was divided into quartiles according to hemoglobin concentration, and differences in clinical and laboratory characteristics between the groups were evaluated. RESULTS: A total of 258 men with STEMI were recruited, 22% of whom suffered from anemia according to the World Health Organization classification (hemoglobin < 13 g/dl). Men in the lowest quartile of hemoglobin concentration presented with significantly lower white blood cell and platelet counts (9.6 ± 2.9 vs. 12.6 ± 3.6 x 103/µl, P < 0.001) and (231 ± 79 vs. 263 ± 8 x 103/µl, P < 0.01), respectively, despite higher inflammatory biomarkers (C-reactive protein and fibrinogen) compared with patients in the upper hemoglobin concentration quartile. Reticulocyte production index was not significantly higher in anemic patients, with a value of 1.8, 1.4, 1.5 and 1.6 in the ascending hemoglobin quartiles, respectively (P = 0.292). CONCLUSIONS: Anemic men with STEMI have relatively lower leukocyte and platelet counts as well as a reduced reticulocyte count despite higher inflammatory biomarkers. These findings might suggest inadequate bone marrow response.