Optimizing Anticoagulation in Older Patients with Nonvalvular Atrial Fibrillation
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Purpose of Review
We sought to review the current issues on optimization of anticoagulation in elderly patients with nonvalvular atrial fibrillation (NVAF).
Advanced age is a risk factor for stroke and as one advances in age, the risk of stroke also increases. One of the many challenges of oral anticoagulation for stroke prevention in the elderly patients with NVAF is the underutilization of anticoagulants. Commonly cited reasons for hesitation by physician in prescribing oral anticoagulants are advanced age, increase risk of bleeding, and the difficulty in maintaining an adequate time in therapeutic range and the need for frequent monitoring for those who are given warfarin. The non-vitamin K antagonist oral anticoagulants (NOAC) have been shown to have similar or superior efficacy, and a better safety profile compared with warfarin due to its wider therapeutic window, low interaction with food, and less frequent monitoring of anticoagulation levels. It is also important to note that renal dysfunction is becoming increasingly common in elderly patients with AF. This poses a therapeutic challenge for physicians due to a higher bleeding risk; thus, renal function should be taken into consideration when prescribing NOACs. Warfarin, on the other hand, remains to be a viable therapeutic option in certain clinical scenarios.
In elderly patients, the choice of oral anticoagulants for stroke prevention in NVAF should be individualized and should include considerations for the best estimate of absolute benefit weighed against bleeding risks in order to optimize anticoagulation.
KeywordsAtrial fibrillation Oral anticoagulant Elderly Chronic kidney disease Warfarin
International normalized ratio
Non-vitamin K antagonist oral anticoagulants
Randomized controlled trial
Stroke prevention in atrial fibrillation
Time within therapeutic range
Vitamin K antagonist
Compliance with Ethical Standards
Conflict of Interest
Drs. Te, Chao and Chen declare that they have no conflict of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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