Safety and Effectiveness of Apixaban in Very Elderly Patients With Non-valvular Atrial Fibrillation (NVAF) Compared to Warfarin Using Administrative Claims Data

Study Overview
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Brief Summary
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The objective of this study is to investigate safety and effectiveness of apixaban compared to warfarin in very elderly patients with Non-valvular atrial fibrillation (NVAF). In addition to the absolute age, effects on higher age-related risk factors on relative risk of apixaban to warfarin is also investigated through subgroup analyses.

Detailed Description
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This is a retrospective non-intervention observational study to evaluate the difference in safety and effectiveness between apixaban and warfarin using a database provided by Medical Data Vision Co. Ltd. (MDV Co. Ltd.). Eligible patients will be extracted from the database and allocated to the pre-defined cohorts based on the actual age, age of NVAF diagnosis and types of anticoagulant therapy. Patient characteristics will be balanced by an Inverse probability of treatment weighting (IPTW) method, and risk of stroke/SE (primary effectiveness endpoint) and major bleeding (primary safety endpoint) will be compared.

Official Title
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Safety and Effectiveness of Apixaban in Very Elderly Patients With NVAF Compared to Warfarin Using Administrative Claims Data

Conditions
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Non-valvular 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 must meet all the following inclusion criteria to be eligible for inclusion in the study. Diagnosed with Atrial fibrillation (AF) anytime in the baseline period or on the index date, also have definitive diagnosis of AF anytime in the baseline period, on the index date, or post-index period. Prescribed apixaban or warfarin on or after the day of AF diagnosis. The first observed prescription will be used to identify the patient's index date and treatment cohort No use of the any Oral anticoagulants (OAC)s during the baseline period (the 180 days before the index date) Age of 18 years or older on the index date. Index date is at age 80 or older Exclusion Criteria: Patients meeting any of the following criteria will not be included in the study: Having a diagnosis of valvular atrial fibrillation, post-operative atrial fibrillation, rheumatic atrial fibrillation or mechanical-valvular atrial fibrillation during the baseline and post-index period Having a cardiac surgery procedure record during the baseline period Having a joint replacement procedure record during the baseline period Having a procedure of prosthetic heart valve during the baseline period Having a diagnosis of venous thromboembolism during the baseline period Female patients with pregnancy during the follow-up period Patients prescribed off-label doses of OACs (per Japanese package insert of each OAC) or patients treated with OAC but in off-label or contraindicated manners.

Ages Eligible for Study
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Minimum Age: 80 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 cohort (Reference)<br>Patients with NVAF treated with warfarin | Drug: Warfarin<br>* This is observational study and the patients in the warfarin cohort include those who are exposed to warfarin in the real world settings.<br>|
| Apixaban cohort<br>Patients with NVAF treated with apixaban | Drug: Apixaban<br>* This is observational study and the patients in the apixaban cohort include those who are exposed to apixaban in the real world settings.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to incidence of a composite stroke and of systemic embolism |  | Maximum of ８ years (From 26 February 2013 to 31 December 2021) | 
| Time to Incidence of Systemic Embolism |  | Maximum of ８ years (From 26 February, 2013 to 31 December, 2021) | 
| Time to incidence of major bleeding | Major bleeding is defined as any bleeding requiring hospitalization. | Maximum of ８ years (From 26 February, 2013 to 31 December, 2021) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to Incidence of Cardiogenic Cerebral Embolism |  | Maximum of ８ years (From 26 February, 2013 to 31 December, 2021) | 
| Time to Incidence of Cerebral Infarction |  | Maximum of ８ years (From 26 February, 2013 to 31 December, 2021) | 
| Time to Incidence of Intracranial Hemorrhage |  | Maximum of ８ years (From 26 February, 2013 to 31 December, 2021) | 
| Time to Incidence of Gastrointestinal Bleeding |  | Maximum of ８ years (From 26 February, 2013 to 31 December, 2021) | 
| Time to Incidence of Intraocular Bleeding |  | Maximum of ８ years (From 26 February, 2013 to 31 December, 2021) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Stroke, Apixaban, Warfarin