[Risk of hemorrhage with oral anticoagulants for deep vein thrombosis].

Despite standardized tests (PT-INR) and better definition of therapeutic objectives, oral anticoagulation still leads to a significant number of hemorrhagic events. The risk is higher during the initial phase of treatment and for arterial indications, but must also be considered for other situations, including deep vein thrombosis, where the risk is less well defined. This risk can now be quantified on the basis of recent data used to identify at risk populations. The risk scores account for age, gender, associated cancer, weight, history of digestive tract bleeding or stroke, and comorbidity (recent myocardial infarction, hematocrit<30%, serum creatinine > 15 mg/l, diabetes). A high score is associated with higher risk of hemorrhagic events. Besides the patient's clinical status, the risk of hemorrhage is related to compliance, the level of anticoagulation, and drug interactions. Specialized monitoring centers provide a means of reducing the risk of morbidity and mortality. New anticoagulation agents must be developed to reduce the risk of hemorrhage which remains an important cause of morbidity and mortality, particularly in the elderly and patients at risk.