Comparative Effectiveness and Safety Between Warfarin and Dabigatran

Study Overview
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Brief Summary
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This is a comparative effectiveness and safety study of clinical events among patients taking either dabigatran or warfarin. There is no formal hypothesis to be tested, but rather to provide the estimates on the incidence of stroke and systemic embolism (effectiveness) and bleeding events (safety) using 95% confidence interval for comparison between those non0-valvular atrial fibrillation patients taking dabigatran vs. warfarin using a large, nation-wide claims data in Japan.

Detailed Description
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This is a comparative effectiveness and safety study of clinical events among patients taking either dabigatran or warfarin. There is no formal hypothesis to be tested, but rather to provide the estimates on the incidence of stroke and systemic embolism (effectiveness) and bleeding events (safety) using 95% confidence interval for comparison between those non-valvular atrial fibrillation patients taking dabigatran vs. warfarin using a large, nation-wide claims data in Japan.

Official Title
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Comparative Effectiveness and Safety Between Warfarin and Dabigatran Using Real World Claims Data of Japanese Non-valvular Atrial Fibrillation Patients

Conditions
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Atrial Fibrillation

Intervention / Treatment
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* Drug: Warfarin
* Drug: Dabigatran


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients aged >18 year-old with confirmed diagnosis of Non-Valvular Atrial Fibrillation (NVAF) (ICD 10 code I48) having a first prescription (index date) of either dabigatran or warfarin between 14 March 2011 to 30 June 2016 having no prescription of any Oral Anticoagulants (OACs) for 12 months prior to the index date (this period is defined as the baseline period) Exclusion Criteria: patients having less than 12 months of enrolment prior to the index date being dialysis or kidney transplant recipients in baseline period having either atrial flutter, valvular atrial fibrillation (AF) mechanical valve placement, rheumatic AF and/or mitral valve prolapse/regurge/stenosis in baseline period having record of deep vein thrombosis or pulmonary embolism < 6 months before AF diagnosis in baseline period

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Atrial Fibrillation<br>patients with atrial fibrillation | Drug: Warfarin<br>* patients treated with warfarin<br>Drug: Dabigatran<br>* patients treated with Dabigatran<br>* Other names: PRADAXA;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence Rate of Stroke and Systemic Embolism (SE) | Incidence rate of stroke and systemic embolism (SE). | From the index date to end of treatment with > 14 day grace period, switch to another OAC, end of continuous enrolment, end of study period or death, outcome event of stroke and systemic embolism, ie., up to 6.5 years. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence Rate of Major Bleeding | Incidence rate of major bleeding defined by any bleeding event associated with hospitalization claims and/or transfusion claims. | From the index date to end of treatment with > 14 day grace period, switch to another OAC, end of continuous enrolment, end of study period or death, outcome event of major bleeding, ie., up to 6.5 years. |