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Japan has health insurance provided by the social insurance system 1 (referred to below simply as "health insurance"), and when a citizen is examined and/or treated at a medical institution, he/ she presents to that institution a health insurance certificate containing information identifying him/herself and his/her insurance provider, and he/she is then responsible for only a fixed proportion of the medical expenses. The medical institution invoices the insurance provider for the remainder of the sum, via a claims processing and payment organization, on the basis of information in the health insurance certificate. Health insurance is provided by multiple bodies, on the basis of occupation, geography, and age (eg, elderly and geriatric), as follows: 2 • People aged 75 or older can join the medical care system for the late elderly, administered by local governments. • People less than 75 years old, primarily those who are employees of small, medium-sized, or long-established businesses, and/or are in temporary employment, and their dependents, are covered by health insurance administered by the Japan Health Insurance Association, except for employment-related injury. • People less than 75 years old, primarily those who are employees of large businesses, and their dependents, are covered by health insurance administered by health insurance societies, except for employment-related injury.

No abstract

Catheter ablation for atrial fibrillation (AF) has been an established and frequently utilized approach in a variety of clinical settings. Nevertheless, real-world data about the clinical course of AF patients after initial catheter ablation remain limited, and these are mainly derived from particular registries or selected high-volume centers.In this study, we used health check-ups and insurance claims database from a Japanese insurance organization. The study population was comprised of 1777 patients who underwent catheter ablation for AF before June 2016. During the 3-year follow-up period, 396 (22.3%) patients underwent at least one repeated AF ablation, while 74 (4.2%) underwent two or more repeated ablations. In multivariate Cox regression analysis, longer time after AF diagnosis (7-11 months and ! 12 months versus 1-6 months) (HR, 1.05; 95% CI, 1.01-1.08 and HR, 1.04; 95% CI 1.02-1.07) was independently associated with repeated ablation. The discontinuation rates of OACs and AADs after the first ablation were 26.7% and 63.0% at 3 months and 75.2% and 89.1% at 1 year after the initial ablation, respectively. The former was independently associated with shorter time after AF diagnosis and lower diastolic blood pressure, whereas the latter was independently associated with older age, smaller CHADS2 score, and shorter time after AF diagnosis.We presented real-world data regarding the clinical course of young Japanese AF patients after initial catheter ablation based on a claims database in Japan.