Treatment Patterns Among Patients With Venous Thromboembolism in the United States

Study Overview
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Brief Summary
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The purpose of this study is to assess outpatient treatment patterns following hospitalization for venous thromboembolism (VTE). VTE is a condition that occurs when blood clot forms in the vein. This is a retrospective study (assessments on events that have already occurred) of healthcare claims from databases. The study sponsors will assess healthcare claim records of patients treated with either apixaban or warfarin. Assessment includes treatment persistence, switch, and stopping therapy, along with recurrent VTE and bleeding.

Official Title
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Post-Discharge Treatment Patterns and Outcomes in Patients With Venous Thromboembolism

Conditions
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Venous Thromboembolism

Intervention / Treatment
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* Drug: apixaban
* Drug: warfarin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: inpatient hospitalization with primary discharge diagnosis of venous thromboembolism (VTE) (this is the index hospitalization) treatment with apixaban or warfarin during the hospitalization at least 18 years of age Exclusion Criteria: Hospitalization for VTE within 6 months prior to the index hospitalization Diagnosis of atrial fibrillation/flutter or procedure for mechanical heart valve in the 6 months prior to the index hospitalization Procedure for inferior vena cava filter or diagnosis of pregnancy during the study period Prior use of oral anticoagulants or parenteral anticoagulants

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 |
| --- | --- |
| apixaban<br>Patients treated with apixaban | Drug: apixaban<br>* patients treated with apixaban<br>|
| warfarin<br>patients treated with warfarin | Drug: warfarin<br>* patients treated with warfarin<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Inpatient Treatment | Proportion of patients treated with apixaban or warfarin during hospitalization for venous thromboembolism. | Up to 5.5 years | 
| Post-hospitalization treatment patterns | Proportion of patients who continue on apixaban or warfarin following discharge from the hospital. | Assessed from hospital discharge date to up to 30 days following discharge date | 
| Longterm treatment utilization | Among patients who continue apixaban or warfarin post-discharge, assess treatment duration; including persistence, switch and discontinuation. | assessed from outpatient treatment start date up to the earliest of treatment discontinuation or switch, or end of study period. Assessed up to 4 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Recurrent Venous Thromboembolism (VTE) | Patients with at least one hospitalization for recurrent VTE. | assessed from outpatient treatment start date up to the earliest of treatment discontinuation or switch, or end of study period. Assessed up to 4 years | 
| Major bleeding | Patients with at least one hospitalization for major bleeding. | assessed from outpatient treatment start date up to the earliest of treatment discontinuation or switch, or end of study period. Assessed up to 4 years | 
| Clinically Relevant Non-major Bleeding | Proportion of patients with at least one inpatient or outpatient encounter for clinically relevant non-major bleeding. | assessed from outpatient treatment start date up to the earliest of treatment discontinuation or switch, or end of study period. Assessed up to 4 years |