Yukihiro Koretsune1, Takeshi Yamashita2, Masahiro Yasaka3, Eisei Oda4, Daisuke Matsubayashi5, Kaori Ota5, Masafumi Kobayashi6, Yasuyuki Matsushita7, Jumpei Kaburagi8, Kei Ibusuki8, Atsushi Takita9, Mikio Iwashita8, Takuhiro Yamaguchi10. 1. National Hospital Organization, Osaka National Hospital, Osaka, Japan. Electronic address: koretune@onh.go.jp. 2. The Cardiovascular Institute, Tokyo, Japan. 3. Department of Cerebrovascular Medicine and Neurology, National Hospital Organization, Kyushu Medical Center, Fukuoka, Japan. 4. Medical TOUKEI Corporation, Tokyo, Japan. 5. Medical Data Vision Co Ltd., Tokyo, Japan. 6. Department of Corporate Planning, Linical Co Ltd., Osaka, Japan. 7. EU Biostatistics & Data Management, Daiichi Sankyo Europe GmbH, Munich, Germany. 8. Medical Science Department, Daiichi Sankyo Co Ltd., Tokyo, Japan. 9. Safety and Risk Management Department, Daiichi Sankyo Co Ltd., Tokyo, Japan. 10. Division of Biostatistics, Tohoku University Graduate School of Medicine, Miyagi, Japan.
Abstract
BACKGROUND: Big data are gaining attention as a valuable resource for providing insights into a range of issues and questions in healthcare. We evaluated the capacity of a Japanese healthcare database to conduct epidemiological research in non-valvular atrial fibrillation (NVAF). METHODS AND RESULTS: We examined data collected between April 2008 and September 2013 in a Japanese healthcare database. Prior to the risk factor analysis, we validated the criteria for defining the occurrence of a stroke, systemic embolic event (SEE), and intracranial bleeding event during the study period. The validity was considered appropriate based on the resulting high positive predictive values. The data of 18,998 NVAF patients demonstrated that the incidence rates of stroke, SEE, and any bleeding events were 2.2, 0.08, and 2.4 per 100 patient-years, respectively. In patients who had not been treated with an anticoagulant, incidence of stroke significantly increased in higher CHADS2 or CHA2DS2-VASc score, 1.7 and 1.5 fold by 1 point increase, respectively. The use of a proton pump inhibitor (PPI) was also identified as an independent risk factor for stroke. In patients who had been treated with an anticoagulant, the independent risk factors for any bleeding events were hypertension, renal dysfunction, hepatic failure, medical history of stroke, older age (≥65 years), use of nonsteroidal anti-inflammatory drug, and PPIs. CONCLUSION: The data obtained in this study were comparable with results obtained in prospective cohort studies conducted in Japan.
BACKGROUND: Big data are gaining attention as a valuable resource for providing insights into a range of issues and questions in healthcare. We evaluated the capacity of a Japanese healthcare database to conduct epidemiological research in non-valvular atrial fibrillation (NVAF). METHODS AND RESULTS: We examined data collected between April 2008 and September 2013 in a Japanese healthcare database. Prior to the risk factor analysis, we validated the criteria for defining the occurrence of a stroke, systemic embolic event (SEE), and intracranial bleeding event during the study period. The validity was considered appropriate based on the resulting high positive predictive values. The data of 18,998 NVAF patients demonstrated that the incidence rates of stroke, SEE, and any bleeding events were 2.2, 0.08, and 2.4 per 100 patient-years, respectively. In patients who had not been treated with an anticoagulant, incidence of stroke significantly increased in higher CHADS2 or CHA2DS2-VASc score, 1.7 and 1.5 fold by 1 point increase, respectively. The use of a proton pump inhibitor (PPI) was also identified as an independent risk factor for stroke. In patients who had been treated with an anticoagulant, the independent risk factors for any bleeding events were hypertension, renal dysfunction, hepatic failure, medical history of stroke, older age (≥65 years), use of nonsteroidal anti-inflammatory drug, and PPIs. CONCLUSION: The data obtained in this study were comparable with results obtained in prospective cohort studies conducted in Japan.