Management of Venous Thromboembolism in the Elderly
Tóm tắt
In this review the authors discuss the use of oral and parenteral anticoagulants for the prevention and treatment of venous thromboembolism (VTE) in the elderly. The use of anticoagulant agents in VTE prophylaxis and treatment in the elderly is complicated by an increase with age in the presence of multiple risk factors and co-morbidities that may increase the risk of both VTE and bleeding. Age itself is identified as an independent risk factor for thromboembolism. VTE is underdiagnosed in the elderly population, and routine prophylaxis frequently falls short of the levels required according to level of risk. Although appropriate anticoagulation of at-risk patients offers a means of reducing the significant VTE burden in this population, concerns have been raised over the use of anticoagulants in a patient group in whom multiple risk factors are common. Bleeding in the elderly can be exacerbated by reduced renal clearance and hypersensitivity to oral anticoagulants that may lead to over-anticoagulation. Although bleeding due to anticoagulant therapy is a serious issue in the elderly, it is often overemphasised, given the therapeutic value otherwise observed in treating this patient group. Warfarin is still used in VTE prophylaxis after orthopaedic surgery and for long-term VTE treatment. Unfractionated and low-molecular-weight heparins (LMWHs) have been shown to be safe and effective in the prophylaxis of VTE, and are now being shown to be as effective as warfarin in the initial and long-term treatment of VTE. LMWHs confer the advantage over unfractionated heparin of subcutaneous once-daily administration with no requirement for laboratory monitoring of their anticoagulant effect, which allows for the convenience of outpatient therapy. New anticoagulants that may be of potential benefit in this patient population include fondaparinux sodium, but clinical experience of this drug in the elderly remains limited.
Tài liệu tham khảo
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