Background: Elderly patients with atrial fibrillation (AF) are at a higher risk for all-cause mortality and heart failure. Rate control is an essential component in AF management. This exploratory study assessed the relationship between resting heart rate during AF at baseline and clinical outcomes in Japanese elderly non-valvular AF (NVAF) patients, using the All Nippon AF In the Elderly Registry (ANAFIE) dataset., Methods: This sub-cohort included patients who agreed to participate and presented with AF at enrollment in the ANAFIE study. They were categorized into six groups according to the resting heart rate during AF. Outcomes included 2-year cumulative incidences of stroke/systemic embolic events (SEE), ischemic stroke, major bleeding, cardiovascular (CV) events, CV death, all-cause death, and net clinical outcome, a composite of stroke/SEE, major bleeding, and all-cause death., Results: Of the 8292 patients included in this sub-cohort (paroxysmal, 1496; non-paroxysmal, 6796), 90 % of patients were using anticoagulants. Higher heart rate was more frequently reported in women and in patients with paroxysmal AF and was associated with increased use of direct oral anticoagulants (DOACs) and antiarrhythmic drugs. Heart rate ≥110 beats per minute (bpm) was associated with a significantly higher incidence of cardiac events and numerically higher incidences of CV death and all-cause death compared with a heart rate of 60 to <80 bpm, all of which were driven by an increased risk in patients with non-paroxysmal AF. Hazard ratios by the type of anticoagulant for each clinical outcome were comparable across all heart rate categories, indicating no significant interactions., Conclusions: Elderly Japanese patients with non-paroxysmal NVAF and a heart rate ≥110 bpm have an increased risk of cardiac events. There was no interaction between heart rate category and the relative risk of adverse clinical events in patients taking DOACs compared with those taking warfarin., Competing Interests: Declaration of competing interest Takanori Ikeda received research grants from Daiichi Sankyo, Medtronic Japan, and Japan Lifeline and honoraria from Ono Pharma, Bayer Yakuhin, Daiichi Sankyo, Bristol-Myers Squibb, and Pfizer. Additionally, Takanori Ikeda was a member of the advisory board for Bayer Yakuhin, Bristol-Myers Squibb, and Daiichi Sankyo. Takeshi 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, Bristol-Myers Squibb, and Ono Pharmaceutical. Masaharu Akao received research funding from Bayer and Daiichi Sankyo, and remuneration from Bristol-Myers Squibb, Nippon Boehringer Ingelheim, Bayer, and Daiichi Sankyo. Hirotsugu Atarashi received remuneration from Daiichi Sankyo. Yukihiro Koretsune received remuneration from Daiichi Sankyo, Bayer, and Nippon Boehringer Ingelheim. Ken Okumura received remuneration from Nippon Boehringer Ingelheim, Daiichi Sankyo, Johnson & Johnson, and Medtronic. Wataru Shimizu received research funding from Bristol-Myers Squibb, Daiichi Sankyo, and Nippon Boehringer Ingelheim, and patent royalties/licensing fees from Daiichi Sankyo, Pfizer Japan, Bristol-Myers Squibb, Bayer, and Nippon Boehringer Ingelheim. Hiroyuki Tsutsui received research funding from Daiichi Sankyo, Mitsubishi Tanabe Pharma, Nippon Boehringer Ingelheim, and IQVA services Japan, remuneration from Daiichi Sankyo, Bayer, Nippon Boehringer Ingelheim, Pfizer Japan, Otsuka Pharmaceutical, and Mitsubishi Tanabe Pharma, scholarship funding from Daiichi Sankyo, Mitsubishi Tanabe Pharma, and Teijin Pharma, and consultancy fees from Novartis Pharma, Pfizer Japan, Bayer, Nippon Boehringer Ingelheim, and Ono Pharmaceutical. Kazunori Toyoda received remuneration from Daiichi Sankyo, Bayer, Bristol-Myers Squibb, Takeda, and Nippon Boehringer Ingelheim. Atsushi Hirayama participated in a course endowed by Boston Scientific Japan, and has received research funding from Daiichi Sankyo and Bayer, and remuneration from Bayer, Daiichi Sankyo, Bristol-Myers Squibb, Nippon Boehringer Ingelheim, Sanofi, Astellas Pharma, Sumitomo Dainippon Pharma, Amgen Astellas BioPharma, and AstraZeneca, and patent royalties/licensing fees from Toa Eiyo M. Masahiro Yasaka received research funding from Nippon Boehringer Ingelheim, and remuneration from Nippon Boehringer Ingelheim, Daiichi Sankyo, Bayer, Bristol-Myers Squibb, Pfizer Japan, and CSL Behring. Takenori Yamaguchi acted as an advisory board member of Daiichi Sankyo, and received remuneration from Daiichi Sankyo and Bristol-Myers Squibb. Satoshi Teramukai 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. Tetsuya Kimura has stock and is an employee of Daiichi Sankyo. Yoshiyuki Morishima and Atsushi Takita are employees of Daiichi Sankyo. Hiroshi Inoue received remuneration from Daiichi Sankyo, Bayer, and Bristol-Myers Squibb, and consultancy fees from Daiichi Sankyo., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.) more...