White blood cell subtypes are associated with a greater long-term risk of death: After acute myocardial infarction

We evaluated the association between white blood cell counts and long-term mortality rates in 2,129 patients (mean age, 65.3 ± 13.5 yr; 69% men) who had survived acute myocardial infarction. We obtained white blood cell counts and differential counts of white blood cell subtypes within the first 72 hours of hospital admission. The primary outcome was all-cause death at 1, 5, and 10 years after acute myocardial infarction. In regard to death in the long term, we found significant negative linear associations (lymphocytes), positive linear associations (neutrophils and the neutrophil-to-lymphocyte ratio), and nonlinear U-shaped associations (basophils, eosinophils, monocytes, and total white blood cell count). After multivariate adjustment for the Soroka Acute Myocardial Infarction risk score, lymphocytes (strongest association), neutrophil-to-lymphocyte ratio, and eosinophils were independently associated with death for up to 10 years after hospital discharge. The independent associations weakened over time. We conclude that lymphocyte count, neutrophil-to-lymphocyte ratio, and eosinophil count are independently and incrementally associated with death in the long term after acute myocardial infarction.