C-reactive protein, cardiovascular issues of an acute-phase protein: an update for the clinician

Inflammation is an important pathogenic factor for the development of atherosclerotic cardiovascular disease. Currently, the most frequently used biomarker reflecting systemic inflammation is C-reactive protein (CRP), an acute-phase protein produced primarily by hepatocytes under the influence of interleukin-6, interleukin-1 beta, and tumor necrosis factor. Growing evidence from epidemiological studies has shown a robust association between elevated serum or plasma CRP concentrations and the incidence of a first cardiovascular adverse event (including acute myocardial infarction, ischemic stroke, and sudden cardiac death) in the general population, as well as recurrence of major adverse cardiovascular events among patients with established disease. The additive value that CRP measurement gives to traditional risk factors is reflected in novel cardiovascular risk calculators and in current intervention regimens, which already consider CRP as a target therapeutic. However, the variations in CRP levels, that depend on sex, ethnicity, hormonal status, and some peculiarities of the measurement assays, must be taken into consideration when deciding to implement CRP as a useful biomarker in the study and treatment of atherosclerotic cardiovascular disease. This review aims to offer an updated vision of the importance of measuring CRP levels as a biomarker of cardiovascular risk beyond the traditional factors that estimate the risk of atherosclerotic disease.