Studies have shown that many patients with atrial fibrillation (AF) who are at high risk for thrombotic stroke and would benefit from anticoagulant prophylaxis, with agents such as warfarin, are not receiving this therapy. The reasons for this are not clear.OBJECTIVE
The authors aimed to identify trends in the prevalence of AF and stroke prophylaxis with anticoagulant medication.DESIGN
This was an analysis of data from DIN-LINK, an electronic, primary-care database of patients' clinical, demographic and socioeconomic information, compiled by general practitioners in the UK. This study analyzed DIN-LINK data from 131 practices, each of which provided continuous, high-quality data across a 5-year period. The database was searched for patients with diagnosed or active AF who were registered with the selected practices. Factors, such as age, sex, socioeconomic status, stroke risk, comorbidities, and drug use, which could be predictive of anticoagulant therapy, were identified in these patients.OUTCOME MEASURES
The primary outcomes were prevalence of AF and use of anticoagulant therapy.RESULTS
The 131 practices included in this analysis registered an average of 1 million patients each year between 1994 and 2003. During this period the prevalence of diagnosed AF increased from 0.84% in men and 0.83% in women to 1.49% and 1.29%, respectively. This increase was most marked in patients aged 85 years or older. In line with the increase in diagnosis, treatment for AF also increased over the study period. In male patients, oral coagulant therapy increased from 25% in 1994 to 53% in 2003; this escalation was also recorded in female patients, but to a lesser extent (21% in 1994 to 40% in 2003). The disparity between men and women receiving anticoagulants at the end of the study period is notable. The use of antiplatelet drugs also increased from 23% to 29% in men and from 22% to 33% in women. Regression analysis revealed that male sex, increased stroke risk, and a range of cardiovascular disorders (including ischemic heart disease, heart failure, and arterial disease) were associated with increased anticoagulant use. Notably, patients with a very high risk of stroke were five times more likely to receive anticoagulants than those at low risk, but still only 56.5% of high-risk patients were receiving anticoagulant treatment. On the other hand, 38.2% of low-risk patients were being prescribed anticoagulants. Older age, chronic gastrointestinal comorbidities, anemia, nonorganic psychoses, and the use of NSAIDs, antiplatelet drugs, and medication prescribed for peptic ulcers were all associated with decreased use of anti coagulant therapy. Other factors, such as socioeconomic status, degree of urbanization, and geo graphical region, had no effect on whether anticoagulants were prescribed.CONCLUSION
The prevalence of diagnosed AF is increasing, as is anticoagulant therapy for stroke prevention. Many high-risk patients who would benefit from anticoagulants, however, are still not receiving this treatment while others, at low risk of stroke, are being medicated.