Background. The knowledge is still sparse about patient related factors, influencing oral anticoagulation therapy (OAC) rates, in stroke patients with atrial fibrillation (AF). Aims. To assess the use of OAC in ischemic stroke patients diagnosed with AF and to identify patient related factors influencing the initiation of OAC. Methods. In the nationwide Danish Stroke Registry we identified 55,551 patients admitted with acute ischemic stroke from 2003 to 2011. Frequency analysis was used to assess the use of OAC in patients with AF, and logistic regression was used to determine independent predictors of OAC. Results. 17.1% ( ) of ischemic stroke patients had AF. OAC prescription rates were increasing, and in 2011 46.6% were prescribed OAC, 42.5% had a contraindication, and 3.7% were not prescribed OAC without a stated contraindication. Younger age, less severe stroke, and male gender were positive predictors of OAC, while excessive alcohol consumption, smoking, and institutionalization were negative predictors of OAC ( values < 0.05). Conclusions. Advanced age, severe stroke, female gender, institutionalization, smoking, and excessive alcohol consumption were associated with lower OAC rates. Contraindications were generally present in patients not in therapy, and the assumed underuse of OAC may be overestimated. 1. Introduction Atrial fibrillation (AF) is an important risk factor for ischemic stroke [1, 2]. The detection of either permanent or paroxysmal AF has an immediate impact on treatment and risk reduction in stroke patients [3]. It is well known that oral anticoagulant therapy (OAC), until 2011 exclusively in Denmark with vitamin K antagonists (VKA), is indicated as secondary prevention [4] and lowers the relative risk of recurrent stroke by two thirds [5, 6]. Nevertheless, it has repeatedly been alleged that AF patients do not receive OAC as often as it is clinically indicated [7–10]. It has been suggested that physicians may overestimate bleeding risk from OAC and underestimate its benefits in stroke prevention [11, 12]. However, the knowledge about motivations, including patient related factors, driving clinical decision-making, and thus influencing therapy rates, is still sparse. The aim of study was to assess the use of OAC in ischemic stroke patients diagnosed with AF and to identify patient related factors influencing the initiation of OAC in possible eligible patients, based on the nationwide Danish Stroke Registry, in the period from 2003 to 2011. 2. Methods 2.1. The Danish Stroke Registry The Danish National Health Service provides
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