Fibrinogen: Its Role in the Hemostatic Regulation in Atherosclerosis

Numerous epidemiologic studies have clearly shown that high plasma fibrinogen levels are strongly correlated with the frequency of myocardial infarction, stroke, and peripheral atherosclerosis. These data indicate that measurements of fibrinogen should be included in cardiovascular risk factor profiles. Since thrombosis is recognized as the central mechanism of these atherosclerotic complications, it seems advisable to accept the predictive value of this protein. Fibrinogen is involved in platelet aggregation, blood rheology, and endothelial cell injury, which are thought to play a key role in thrombogenesis. Fibrinogen may predict bypass occlusion but appears to have no significant influence on restenosis following successful coronary angioplasty. Furthermore, fibrinogen represents an acute-phase protein, being of no specificity. Its level varies genetically, as well as circadian and seasonal variations, and is influenced by a number of circumstances and drugs. Plasma levels of fibrinogen decrease by life-style changes, smoking cessation, and different medications such as fibrates, but the risk-lowering effect is not proven yet.