Background: The All Nippon Atrial Fibrillation In the Elderly Registry provides real-world insights into non-valvular atrial fibrillation (NVAF) in >30,000 elderly Japanese patients (aged ≥75 years), including >2,000 nonagenarians. We aimed to investigate outcomes in these patients by age and oral anticoagulant (OAC) type., Methods and Results: This prospective, multicenter, observational, cohort, 2-year follow-up study included elderly patients with NVAF who were able to attend hospital visits. The incidences of stroke/systemic embolic events (SEE), major bleeding, intracranial hemorrhage (ICH), cardiovascular death, all-cause death, and major adverse cardiovascular or neurological events (MACNE) were evaluated by age. Incidence rates increased significantly with age. Stroke/SEE, major bleeding, and ICH incidences plateaued in patients aged ≥90 years. Direct OACs (DOACs) yielded a numerically lower event incidence vs. warfarin in all age groups and endpoints, except for major bleeding in patients aged ≥90 years. DOACs (vs. warfarin) were significantly associated with a lower risk of stroke/SEE, major bleeding, and ICH in the ≥80-<85 years group, and reduced cardiovascular and all-cause death in the ≥75-<80 years group. In the ≥90 years subgroup, major bleeding history was a risk factor for all-cause death., Conclusions: Although DOAC vs. warfarin offers potential benefits for stroke prevention, limitations occurred in reducing major bleeding among those aged ≥90 years, indicating a potential benefit of very-low-dose DOAC for this demographic., Competing Interests: S.S. received research funding from Daiichi Sankyo, and remuneration from Bristol-Myers Squibb and Daiichi Sankyo. T. Yamashita received research funding from Bristol-Myers Squibb, Bayer, and Daiichi Sankyo, manuscript fees from Daiichi Sankyo and Bristol-Myers Squibb, and remuneration from Daiichi Sankyo, Bayer, Pfizer Japan, and Bristol-Myers Squibb. M.A. received research funding from Bayer and Daiichi Sankyo, and remuneration from Bristol-Myers Squibb, Nippon Boehringer Ingelheim, Bayer, and Daiichi Sankyo. H.A. received remuneration from Daiichi Sankyo. T.I. received research funding from Daiichi Sankyo, and remuneration from Daiichi Sankyo, Pfizer Japan, and Bayer. Y.K. received remuneration from Daiichi Sankyo, Bristol-Myers Squibb, and Nippon Boehringer Ingelheim. K.O. received remuneration from Nippon Boehringer Ingelheim, Daiichi Sankyo, Johnson & Johnson, and Medtronic. W.S. received research funding from Daiichi Sankyo, and Nippon Boehringer Ingelheim, and remuneration from Daiichi Sankyo, Pfizer Japan, Bristol-Myers Squibb, Bayer, and Nippon Boehringer Ingelheim. H.T. received research funding from Daiichi Sankyo and Nippon Boehringer Ingelheim, remuneration from Daiichi Sankyo, Bayer, Nippon Boehringer Ingelheim, and Pfizer Japan, scholarship funding from Daiichi Sankyo, and consultancy fees from Pfizer Japan, Bayer, and Nippon Boehringer Ingelheim. K.T. received remuneration from Daiichi Sankyo, Bayer, Bristol-Myers Squibb, Otsuka, and Novartis. A.H. participated in a course endowed by Boston Scientific Japan, has received research funding from Daiichi Sankyo and Bayer, and remuneration from Bayer, Daiichi Sankyo, Bristol-Myers Squibb, and Nippon Boehringer Ingelheim. M.Y. received research funding from Nippon Boehringer Ingelheim, and remuneration from Nippon Boehringer Ingelheim, Daiichi Sankyo, Bayer, Bristol-Myers Squibb, and Pfizer Japan. T. Yamaguchi acted as an advisory board member for Daiichi Sankyo and has received remuneration from Daiichi Sankyo and Bristol-Myers Squibb. S.T. received research funding from Nippon Boehringer Ingelheim and remuneration from Daiichi Sankyo, Sanofi, Takeda, Chugai Pharmaceutical, Solasia Pharma, Bayer, Sysmex, Nipro, NapaJen Pharma, Gunze, and Atworking. M.F., Y.M., and A.T. are employees of Daiichi Sankyo. H.I. received remuneration and consultancy fees from Daiichi Sankyo. T. Yamashita, T.I., W.S, and H.T. are Associate Editors for Circulation Journal. A.H. was a member of Circulation Reports’ Editorial Team., (Copyright © 2024, THE JAPANESE CIRCULATION SOCIETY.)