The bleeding with antithrombotic therapy study 2: Rationale, design, and baseline characteristics of the participants

Masahito Takagi; Kanta Tanaka; Kaori Miwa; Makoto Sasaki; Masatoshi Koga; Teruyuki Hirano; Kenji Kamiyama; Yoshiki Yagita; Yoshinari Nagakane; Haruhiko Hoshino; Tadashi Terasaki; Yusuke Yakushiji; Kohsuke Kudo; Masafumi Ihara; Sohei Yoshimura; Yoshitaka Yamaguchi; Masayuki Shiozawa; Kazunori Toyoda; for BAT2 Investigators

doi:10.1177/2396987320960618

The bleeding with antithrombotic therapy study 2: Rationale, design, and baseline characteristics of the participants

Eur Stroke J. 2020 Dec;5(4):423-431. doi: 10.1177/2396987320960618. Epub 2020 Sep 24.

Authors

Masahito Takagi¹, Kanta Tanaka¹, Kaori Miwa¹, Makoto Sasaki², Masatoshi Koga¹, Teruyuki Hirano³, Kenji Kamiyama⁴, Yoshiki Yagita⁵, Yoshinari Nagakane⁶, Haruhiko Hoshino⁷, Tadashi Terasaki⁸, Yusuke Yakushiji⁹, Kohsuke Kudo¹⁰, Masafumi Ihara¹¹, Sohei Yoshimura¹, Yoshitaka Yamaguchi¹², Masayuki Shiozawa¹, Kazunori Toyoda¹; for BAT2 Investigators

Affiliations

¹ Department of Cerebrovascular Medicine, National Cerebral and Cardiovascular Center, Suita, Japan.
² Institute for Biomedical Sciences, Iwate Medical University, Yahaba, Japan.
³ Department of Stroke and Cerebrovascular Medicine, Kyorin University, Mitaka, Japan.
⁴ Department of Neurosurgery, Nakamura Memorial Hospital, Sapporo, Japan.
⁵ Department of Stroke Medicine, Kawasaki Medical School, Kurashiki, Japan.
⁶ Department of Neurology, Kyoto Second Red Cross Hospital, Kyoto, Japan.
⁷ Department of Neurology, Tokyo Saiseikai Central Hospital, Tokyo, Japan.
⁸ Department of Neurology, Japanese Red Cross Kumamoto Hospital, Kumamoto, Japan.
⁹ Division of Neurology, Department of Internal Medicine, Saga University Faculty of Medicine, Saga, Japan.
¹⁰ Department of Diagnostic Imaging, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
¹¹ Department of Neurology, National Cerebral and Cardiovascular Center, Suita, Japan.
¹² Department of Neurology, Yamagata Prefectural Central Hospital, Yamagata, Japan.

Abstract

Aims: The bleeding risk of current antithrombotic strategies in clinical settings, including recently developed agents, needs to be clarified.

Methods and design: In an investigator-initiated, prospective, multicentre, observational study, patients with cerebrovascular or cardiovascular diseases who were taking oral antiplatelet or anticoagulant agents were enrolled. Compulsory multimodal magnetic resonance images were acquired at baseline to assess cerebral small vessel disease. Six-month follow-up will be performed for two years. The primary outcome is major bleeding as defined by the International Society on Thrombosis and Hemostasis.

Results: Between October 2016 and March 2019, 5306 patients (71.7 ± 11.2 years old, 1762 women) were enrolled. Previous intracranial haemorrhage was documented in 181 patients (3.4%), cerebrovascular disease (including asymptomatic) requiring antithrombotic therapy in 5006 patients (94.3%), and atrial fibrillation in 1061 patients (20.0%). At entry, 3726 patients (70.2%) were taking antiplatelet agents alone, including 551 (10.4%) using dual antiplatelet agents, 1317 (24.8%) taking anticoagulants alone, and the remaining 263 (5.0%) taking both. The leading antiplatelet agent was clopidogrel (2014 patients), and the leading combination of dual antiplatelet medication was clopidogrel plus aspirin (362). Use of direct oral anticoagulants (1029 patients, 19.4%) exceeded warfarin use (554, 10.4%). The number of pivotal bleeding events exceeded 200 in April 2020.

Conclusions: This study is expected to provide the incidence of bleeding complications of recent oral antithrombotics in clinical practice and identify their associations with underlying small vessel disease and other biomarkers. Novel risk stratification models for bleeding risk will be able to be created based on the study results.

Keywords: Antiplatelet therapy; anticoagulation therapy; cardiovascular disease; cerebrovascular disease; intracranial haemorrhage; small vessel disease; stroke.