A review of the safety of anticoagulants in older people using the medicines management pathway: weighing the benefits against the risks

Abstract

Anticoagulant drugs maintain a high potential for adverse events due to their inherent risk of haemorrhage and/or complex pharmacology. In addition, compromising the safety of these agents is the context in which they are principally used; that is, in the long-term prevention of thromboembolic diseases in an older patient population. These challenges are especially pronounced in the prevention of stroke in older persons with atrial fibrillation (AF), where the need for thromboprophylaxis is paramount and in whom the arrhythmia is most prevalent, but where the target population is simultaneously at high risk of adverse drug events. Essentially, this translates to the use of high-risk therapies on an indefinite basis, in persons who have multiple comorbidities, use polypharmacy, and who may have age-related functional and cognitive decline, culminating in a higher potential for medication misadventure. For this reason, anticoagulants mandate extra pharmacovigilance, and therefore the aim of this review is to address some of the key safety considerations in the use of anticoagulant drugs (warfarin, dabigatran, rivaroxaban), spanning the initiation of therapy to its ongoing management. Using the Medication Management Pathway (MMP) as a framework, in this review we canvas and highlight specific developments in practical strategies to facilitate the safe use of anticoagulants (particularly warfarin) in ‘at-risk' elderly patients including: comprehensive risk/benefit assessment using novel risk stratification tools; focused medicines review services; therapeutic drug monitoring services delivered in the primary care setting; and practical education strategies and resources targeting the older patient population. Until newer alternative anticoagulants become viable options for widespread use, clinicians will necessarily need to rely on specific resources and interventions to facilitate the safe use of currently available anticoagulants (i.e. warfarin) in ‘at-risk’ older people.