Thromboembolism in Older Adults

Abstract

Arterial and venous thromboembolism are both more common in older adults. The use of anticoagulants, the mainstay to prevent thromboembolism, requires consideration of the balance between risk and benefit. Such consideration is even more important in the very elderly in whom the risk of anticoagulant-related bleeding and thrombosis are higher. This review will focus on the challenges of implementing and managing anticoagulant therapy in older patients in an era when the options for anticoagulants include not only vitamin K antagonists (VKAs), but also direct-acting oral anticoagulants (DOACs).

Keywords: COVID-19; atrial fbrillation; direct-acting anticoagulant; falls among older adults; venous thomboembolism; vitamin K antagonist (VKA).

Figure 1

Challenges in managing thromboembolism in older patients.

Figure 2

The dynamic between thromboembolic and bleeding risks according to age in various settings. The figure shows the dynamic between thromboembolic and bleeding risks according to age and to clinical indications. In the acute VTE setting, without anticoagulant therapy, the risk of recurrent VTE is very high irrespective of age. Although bleeding risk on anticoagulation increases with age, anticoagulant therapy is associated with a net clinical benefit in acute VTE treatment in younger and older patients. In the secondary VTE prevention setting, the risk of VTE recurrence after a treated index event is lower compared to the acute VTE setting and similar in both younger and older patients. Because of higher bleeding risk, the benefit of anticoagulation for secondary VTE prevention is likely reduced in older patients compared with younger patients. Consequently, VTE guidelines are less strong in recommending extended anticoagulation in older patients. By contrast, the risk of cardioembolic stroke in AF rises with age and thus most older patients continue to benefit from anticoagulant therapy despite a higher bleeding risk. Despite the similar definition of major bleeding, the consequence of a venous thromboembolic event and an arterial thromboembolic event are not equal. Green, thromboembolic risk in absence of anticoagulant therapy; Red, major bleeding risk with anticoagulation.