[Fibrinogen: a risk factor].

More than 10 epidemiologic studies have established that a high fibrinogen level is a thrombotic risk factor. The role of fibrinogen in arterial occlusion is multiple : the atheroma plaque involvement in formation thrombus, erythrocyte aggregation, whole blood and plasma viscosity. Fibrinogen level is high during inflammation and increases with ageing and in tobacco addicts. In coronary disease, it is an independent risk factor of prognosis value. In arterial peripheral disease, it is a risk factor of postsurgical reocclusion. After a stroke, a high level of fibrinogen is a sign of severe disease. The dosage of fibrinogen is quite easy but requires a precise calibration. The determination of genetic polymorphism associated with high fibrinogen level is promising. Many circumstances can modify fibrinogen level and are targets for prophylaxis treatments. The influence of genetic factors is still discussed.