The Effectiveness and Safety of Apixaban in NVAF Patients With History of Osteoporosis and/or Fracture: A Nation-wide Population Based Study

Study Overview
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Brief Summary
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Old age, less body weight and deteriorated renal function are significant clinical factors for the outcomes of atrial fibrillation- so called 'fragile'- and these are common risk factors in osteoporosis and fracture. Therefore, in real world, these risk factors and co-morbidities are commonly considered when it comes to prescribe anticoagulant in atrial fibrillation patients. Recent study even reported that comorbid atrial fibrillation in patients with osteoporosis might be associated with an increased risk of bone fracture and death after fracture. Because there have been very few data about the effectiveness/safety of anticoagulant among non-valvular atrial fibrillation with prior osteoporosis/fracture, this study is planned to provide real-world evidences for this specific type of non-valvular atrial fibrillation patients.

Official Title
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The Effectiveness and Safety of Apixaban Versus Warfarin in Non-valvular Atrial Fibrillation (NVAF) Patients With the History of Osteoporosis and/or Fracture: A Nation-wide Population Based Study

Conditions
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Atrial Fibrillation

Intervention / Treatment
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* Drug: warfarin
* Drug: apixaban


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients aged 18 years or older on the index date Patients had ≥1 medical claim for atrial fibrillation with at least one hospitalization or at least two outpatient visits during the reference period Exclusion Criteria: Patients with valvular atrial fibrillation or transient atrial fibrillation Having ≥ 2 types of oral anticoagulant on the index date who have contraindications to oral anticoagulant confounder factors related to the outcome (osteoporotic fractures)

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 |
| --- | --- |
| Warfarin user<br> | Drug: warfarin<br>* warfarin user<br>|
| Apixaban user<br> | Drug: apixaban<br>* apixaban user<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Composite of ischemic stroke, hemorrhagic stroke and and systemic embolism | Intake period is from July 1, 2015 to Nov 30, 2016. | from index date (1st prescription date for oral anticoagulants during the intake period) to follow up period(the index date- Nov 30, 2016 or outcomes whichever comes first) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Major bleeding including gastrointestinal bleeding, intracranial bleeding, and other bleeding | Intake period is from July 1, 2015 to Nov 30, 2016. | from index date (1st prescription date for oral anticoagulants during the intake period) to follow up period (the index date- Nov 30, 2016 or outcomes whichever comes first) |