The economics of atrial fibrillation: a time for review and prioritization Dominique A. Cadilhac 1,2,3 Stroke associated with atrial fibrillation may occur in up to one third of people who experience an ischemic event, and results in greater stroke severity and poorer health out- comes. The ageing population in developed and developing countries will lead to an increase in the prevalence of atrial fibrillation in society. Detecting people who have atrial fibril- lation and ensuring optimal prevention management is essential for reducing the burden of stroke worldwide. There is evidence that use of anticoagulants is inadequate in primary and secondary prevention of stroke. New anticoagu- lants that have fewer side effects and population screening tools are available. However, there is little information avail- able about the cost-effectiveness of these new options for atrial fibrillation detection and stroke prevention manage- ment over current practice. Since resources for spending in health are limited, it is essential that formal economic analy- ses are undertaken to ensure there are informed and evidence-based decisions on where to best invest stroke prevention resources. It is essential that renewed efforts in the area of atrial fibrillation and options for stroke pre- vention are undertaken within the public health research community. Key words: atrial fibrillation, economics, prevention, stroke Atrial fibrillation (AF) is the most common cardiac arrhyth- mia affecting up to 1·5% of people around the world (1). AF is more common in older people and is reported to affect 5% of people aged 65 years and over (2). Nonvalvular, chronic AF has been associated with about a fivefold increase in stroke incidence (3). The risk of stroke is increased in those with previous systemic embolism, with increasing age and in the presence of heart failure, hypertension, and diabetes (4–7). In addition, the risks are cumulative. For example, in people aged 65–75 years with no risk factors, the annual risk is 4% com- pared with 6% in those with one or more risk factors (8). AF-associated stroke may occur in up to one third of people who experience an ischemic event (9,10). Presence of AF in someone who experiences a stroke is also associated with a greater risk of recurrence and more severe and disabling stroke than in those without AF (10). In a recent national audit of patients with acute stroke in Australia, it was found that stroke survivors with AF had a 1·56 greater odds [95% confidence interval (CI) 1·14 to 2·12] of being discharged to aged care and 1·48 greater odds of dying in a hospital (95% CI 1·08 to 2·03) than patients without AF (11). Several authors using data for European countries have also shown that inpatients costs may be greater when treating stroke in patients with AF than in stroke patients without AF (12–14). The data on whether there are attributes of care provision in hospital that may explain differences in health outcomes and also the cost implications of AF in patients with stroke remain limited. Further research in these areas is needed. Detecting people who have AF and ensuring optimal pre- vention management is essential for reducing the burden of stroke worldwide. In audits of hospital care, it has been shown that only about 30% of stroke patients known to have AF prior to admission were on anticoagulants (15–17). In Taiwan, underuse of anticoagulants was found to be associated with a greater incidence of stroke, whereby only 11% were on warfa- rin prior to stroke (18). Although most patients with stroke who have AF are dis- charged from hospital on antiplatelet or antithrombotic agents, inadequate numbers are prescribed one of the most effective prevention therapies, the anticoagulant warfarin (19). It is acknowledged that the benefits of thromboprophy- laxis may not be applicable to all patients (4). It has been suggested that about 35% of people with AF have irreversible contraindications to anticoagulants (20). Recent evidence from the United Kingdom has shown that only 39% of stroke survivors with AF were discharged or planned to be prescribed anticoagulants in 2010 (15). This may in part be explained by Correspondence: Dominique A. Cadilhac, Stroke and Ageing Research Centre, Department of Medicine, Monash Medical Centre, Southern Clinical School, Monash University, Monash Health Research Precinct (MHRP) Building, Level 1, 43-51 Kanooka Grove, Clayton, Vic. 3168, Australia. E-mail: dominique.cadilhac@monash.edu 1 Stroke and Ageing Research Centre, Department of Medicine, Monash University, Clayton, Victoria, Australia 2 National Stroke Research Institute of Florey Neuroscience Institutes, Heidelberg, Victoria, Australia 3 The University of Melbourne, Melbourne, Victoria, Australia Conflict of interest: None declared. DOI: 10.1111/j.1747-4949.2012.00831.x Leading opinion © 2012 The Author. International Journal of Stroke © 2012 World Stroke Organization Vol 7, August 2012, 477–479 477