Neutrophil count as a risk factor for cardiovascular diseases: how can we manage it?

Neutrophils activation plays a pivotal role in the pathogenesis of atherosclerotic plaque formation, progression and rupture. An association between the leukocyte count and the risk of developing myocardial infarction has been well known for many years; however, only recently did Mendelian randomization studies show that a high neutrophil count is a causal risk factor for atherosclerotic cardiovascular disease. On the other hand, experimental studies show that depletion of circulating neutrophils impairs plaque development. Clopidogrel, an antiplatelet agent, is widely used in combination with aspirin to reduce the incidence of ischemic events in patients treated with coronary stenting. Chronic treatment with this drug reduces inflammatory markers and neutrophil numbers, rarely causing severe leukopenia. The purpose of this review is to present recent evidence showing the link between neutrophil number and the development of cardiovascular diseases and to discuss how the clopidogrel-induced reduction in the neutrophil count may be a beneficial off-target effect of this drug.