Background:Atrial fibrillation (AF) is a common arrhythmic disorder among the elderly, and increases the risk of stroke. Oral anticoagulants (OAC) are highly effective in preventing stroke, and there are evidence-based guidelines for the optimal use of OAC in patients with AF.Methods and Results:The Fushimi AF Registry is a community-based prospective survey of the AF patients in Fushimi-ku, Kyoto, a typical urban community in Japan with a total population of 283,000. Of the 3,282 patients enrolled by October 2012, 1-year follow-up was completed for 2,914 patients. OAC, mainly warfarin, were given to 1,546 patients (53.1%); overused for low-risk patients, and underused for patients at risk, based on the guidelines. Moreover, warfarin was sometimes given at a sub-therapeutic dose; only 54.4% of patients were within the optimal therapeutic range. The 1-year outcomes revealed that the incidences of both stroke and major bleeding were equivalent between patients taking OAC and those without; major clinical events were as follows: (OAC vs. non-OAC) stroke 2.7% vs. 2.8%, ischemic stroke 2.1% vs. 2.0% and major bleeding 1.4% vs. 1.5% (NS for all).Conclusions:The Fushimi AF Registry provides a unique snapshot of current AF management in an urban community in Japan. The present study reveals inappropriate use of OAC for patients with AF, indicating discordance between guideline recommendations and real-world clinical practice. (Circ J2014;78:2166–2172)