Il tromboembolismo venoso nel paziente geriatrico. Rischi e benefici della prevenzione e del trattamento con i farmaci attivi sull'emostasi

Venous thromboembolism is a major cause of morbidity in the elderly and of growing concern in the medical community. The risk of venous thromboembolism (VTE) increases with age. After the age of 75, the annual incidence of VTE is 3/1,000. VTE is a serious and potentially fatal complication associated with surgical trauma, particularly in elderly patients undergoing joint replacement or hip-fracture surgery. Other major factors predisposing to VTE are common in the elderly. Bedridden older patients have a risk of VTE comparable to that of surgical patients at moderate risk. The advantages of anticoagulation may be offset by the risk of bleeding in older subjects: these are often on treatment with drugs that influence the pharmacokinetics of antithrombotic drugs and/or carry diseases that inhibit/potentiate anticoagulation. Oral anticoagulation (OAC) with vitamin K antagonists (warfarin) is the strategy of choice to prevent recurrent events in subjects with a history of recent VTE. Since the risk of serious bleeding is dose and time-dependent, strategies to identify subjects at the highest risk of recurrence of VTE i.e. those that require long-lasting anticoagulation, are urgently needed. In addition to compression ultrasonography (CUS), circulating levels of D-dimer (DD) have been suggested to help identify such subjects. In addition to the risk of bleeding, the incidence of symptomatic VTE during prophylaxis with LMWH and/or warfarin in patients 65 years of age or older who have undergone unilateral total hip arthroplasty, ranges 1-4%. This makes the search for better and safer drugs for the management of VTE mandatory. Experimentally, new direct thrombin inhibitors, factor Xa inhibitors, and inhibitors of the factor VIIa/tissue factor pathway exhibit improved benefit to risk ratios. Despite the importance of lowering the risk of venous thromboembolism in the elderly, in most large-scale clinical trials this population has not been represented adequately.