Potential impact of new oral anticoagulants on the management of atrial fibrillation-related stroke in primary care

Abstract

Aim: Anticoagulant prophylaxis with vitamin K antagonists (such as warfarin) is effective in reducing the risk of stroke in patients with atrial fibrillation (AF). New oral anticoagulants have emerged as potential alternatives to traditional oral agents. The purpose of this review was to summarise the effectiveness and safety of rivaroxaban, dabigatran and apixaban in stroke prevention in patients with AF in phase III trials, evaluate their cost-effectiveness and consider the implications for primary care.

Methodology: A literature search was performed between 2007 and 2012, selecting all phase III trials (ROCKET AF, RE-LY and ARISTOTLE) of new oral anticoagulants and relevant cost-benefit studies.

Results: Evidence shows that all three agents are at least as effective as warfarin in the prevention of stroke and systemic emboli, with similar safety profiles. Cost-benefit studies of rivaroxaban and dabigatran further confirm their potential use as alternatives to warfarin in clinical practice. These observations may allow stratification of the general practice AF population, to help prioritise which patients may benefit from receiving a new oral anticoagulant.

Conclusion: The clinical and economic benefits of the new oral anticoagulants, along with appropriate risk stratification, may enable a higher number of patients with AF to receive effective and convenient prophylaxis for stroke prevention.

Figure 1

Quantifying workload in general practice for introducing new anticoagulants by different categories of AF patient. Patients were categorised into seven groups (A–G), and assigned an order of priority (1–4) for receiving a new OAC. The following assumptions were made: the average General Practice population size in England is 6600 (54), AF has a population prevalence of approximately 1% (3), the incidence of newly diagnosed cases of AF is 0.6 per 1000 (55), approximately 90% of patients with AF are at high or moderate risk of a stroke/transient ischaemic attack using the CHADS₂ score (50); approximately 47% of patients who should be receiving warfarin are not (58); patients with CHADS₂ scores ≥ 2 are not receiving warfarin (59,60), 88% of UK participants have a mean time in therapeutic range of > 65% (49); discontinuation rates are > 25% in the first year for patients with AF started on warfarin (62). AF, atrial fibrillation; OAC, oral anticoagulant.