Study to Gather Information to What Extent Patients Follow the Treatment Regimen of Low-dose Aspirin for Primary and Secondary Prevention of Diseases of the Heart and Blood Vessels

Study Overview
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Brief Summary
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This study aims to gather information to what extent patients follow the treatment regimen of low-dose aspirin for primary and secondary prevention of diseases of the heart and blood vessels. Researcher will collect information about the percentage of time a patient has access to the medication, how long patients continue with the medication and of the proportion of patients who switch from dual-antiplatelet therapy (including low-dose aspirin) to a single antiplatelet therapy. The study will make use of secondary healthcare data sources converted in to Observational Medical Outcomes Partnership (OMOP) common data model within the Observational Health Data Sciences and Informatics (OHDSI) network.

Official Title
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Persistence and Adherence to Low-Dose Aspirin for Primary and Secondary Prevention of Cardiovascular DiseasE Using OHDSI

Conditions
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Myocardial Infarction, Unstable Angina, Stroke (Including Ischaemic Stroke and Transient Ischaemic Attack), Angina, Ischaemic Heart Disease

Intervention / Treatment
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* Drug: Acetylsalicylic Acid (Aspirin, BAYE4465)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged ≥18 years Patients will be selected if they have at least two prescriptions for low-dose aspirin (75-100 mg) between 2008 and 2018 for either: Primary prevention of CVD This is defined as patients who have no history of CVD any time prior to initiation of low-dose aspirin treatment are presumed to use for primary CVD prevention Secondary prevention of CVD This is defined as patients who have a history of CVD any time prior to initiation of low-dose aspirin treatment Patients with at least two prescriptions of low-dose aspirin with a dosage of 75-100mg within the first year of the index date. Restricted to patients with observation for at least 12 months before and 12 after the index date. Exclusion Criteria: - Prescription of low-dose aspirin in 12 months before the index date.

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 |
| --- | --- |
| Low-dose aspirin users<br>Patients who receive low-dose aspirin (75-100mg) for either the primary or secondary prevention of cardiovascular disease (CVD). | Drug: Acetylsalicylic Acid (Aspirin, BAYE4465)<br>* 75-100mg<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Adherence to low-dose aspirin | Adherence low-dose aspirin use will be represented by the medication possession ratio (MPR) | Retrospective analysis from 2007 to 2018 | 
| Persistence to low-dose aspirin | In terms of continuation and discontinuation: Continuation at 30 and 60 day gaps Discontinuation: If patients switched to another antiplatelet therapy If patients reinitiated low-dose aspirin >30 days and >60 days after end of supply i.e. of the pre-specified gap was exceeded If patients stopped low-dose aspirin therapy completely | Retrospective analysis from 2007 to 2018 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to switch from dual-antiplatelet to a monotherapy |  | Retrospective analysis from 2007 to 2018 |