Study Design and Baseline Characteristics of the EXPAND Study: Evaluation of Effectiveness and Safety of Xa Inhibitor, Rivaroxaban for the Prevention of Stroke and Systemic Embolism in a Nationwide Cohort of Japanese Patients Diagnosed as Non-Valvular Atrial Fibrillation

TAKANORI IKEDA,¹ HIROTSUGU ATARASHI,² HIROSHI INOUE,³ SHINICHIRO UCHIYAMA,⁴ TAKANARI KITAZONO,⁵ TAKESHI YAMASHITA,⁶ WATARU SHIMIZU,⁷ MASAHIRO KAMOUCHI,⁸ KOICHI KAIKITA,⁹ KOJI FUKUDA,¹⁰ HIDEKI ORIGASA,¹¹ ICHIRO SAKUMA,¹² KEIJIRO SAKU,¹³ YASUO OKUMURA,¹⁴ YUICHIRO NAKAMURA,¹⁵ HIDEO MORIMOTO,¹⁶ NAOKI MATSUMOTO,¹⁷ AKIHITO TSUCHIDA,¹⁸ JUNYA AKO,¹⁹ NOBUYOSHI SUGISHITA,²⁰ SHOGO SHIMIZU²¹ and HIROAKI SHIMOKAWA¹⁰

¹Department of Cardiovascular Medicine, Toho University Faculty of Medicine, Tokyo, Japan
²Department of Cardiovascular Medicine, Nippon Medical School Tama-Nagayama Hospital, Tokyo, Japan
³Saiseikai Toyama Hospital, Toyama, Toyama, Japan
⁴Clinical Research Center for Medicine, International University of Health and Welfare, Tokyo, Japan
⁵Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Kyusyu University, Fukuoka, Fukuoka, Japan
⁶Cardiovascular Institute Hospital, Tokyo, Japan
⁷Department of Cardiovascular Medicine, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan
⁸Department of Health Care Administration and Management, Kyusyu University Graduate School of Medical Sciences, Fukuoka, Fukuoka, Japan
⁹Department of Cardiovascular Medicine, Kumamoto University, Kumamoto, Kumamoto, Japan
¹⁰Department of Cardiovascular Medicine, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
¹¹Department of Biostatistics and Clinical Epidemiology, Toyama University, Toyama, Toyama, Japan
¹²Hokko Memorial Hospital, Sapporo, Hokkaido, Japan
¹³Department of Cardiology, Fukuoka University School of Medicine, Fukuoka, Fukuoka, Japan
¹⁴Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan
¹⁵Nakamura Cardiovascular Clinic, Itoshima, Fukuoka, Japan
¹⁶Department of Medicine, Fukagawa Municipal Hospital, Fukagawa, Hokkaido, Japan
¹⁷Department of Pharmacology, St. Marianna University School of Medicine, Kawasaki, Kanagawa, Japan
¹⁸Division of Cardiology, JR Sapporo Hospital, Sapporo, Hokkaido, Japan
¹⁹Department of Cardiovascular Medicine, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
²⁰Sugishita Clinic, Gujo, Gifu, Japan
²¹Mashiko Hospital, Kawaguchi, Saitama, Japan

The use of rivaroxaban, a factor Xa inhibitor, has been increasing for prevention of ischemic stroke and systemic embolism in patients with non-valvular atrial fibrillation (AF) in Japan. We conducted the nationwide multicenter study, termed as the EXPAND Study, to address its effectiveness and safety in the real-world practice of patients with non-valvular AF in Japan. The EXPAND Study is a prospective, non-interventional, observational cohort study to evaluate the effectiveness and safety of rivaroxaban in non-valvular AF patients in a real-world clinical practice. A total of 7,178 patients with non-valvular AF were enrolled in 684 medical institutes between November 20, 2012 and June 30, 2014. As for the baseline demographic and clinical characteristics of 7,164 patients, the proportion of female patients was 32.2%, and those of patients with creatinine clearance < 50 mL/min and non-paroxysmal (persistent or permanent) AF were 21.8% and 55.1%, respectively. The proportions of patients complicated with hypertension, congestive heart failure, diabetes mellitus, and a history of ischemic stroke were 70.9%, 25.9%, 24.3%, and 20.2%, respectively. The proportions of patients with a CHADS₂ score ≤ 1 and a CHA₂DS₂-VASc score le; 1 were 37.3% and 13.6%, respectively. They were followed up until March 31, 2016 for a mean follow-up period of approximately 2.5 years. The findings of the EXPAND Study will help to establish an appropriate treatment with rivaroxaban for Japanese patients with non-valvular AF.

keywords —— anticoagulants; atrial fibrillation; Japanese; real world evidence; stroke

===============================

Tohoku J. Exp. Med., 2016, 240, 259-268

Correspondence: Takanori Ikeda, M.D., Ph.D., Department of Cardiovascular Medicine, Toho University Faculty of Medicine, 6-11-1 Omorinishi, Ota-ku, Tokyo 143-8540, Japan.

e-mail: ikety5@gmail.com