Clinical and Economic Burden of Bleeding Events in Patients in the UK With Non-valvular Atrial Fibrillation Treated With Vitamin k Antagonists

Study Overview
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Brief Summary
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The purpose of the study is to estimate the impact of bleeding events in patients in the UK with non-valvular atrial fibrillation (NVAF) treated with vitamin K antagonists (VKA).

Official Title
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Clinical and Economic Burden of Bleeding Events in Patients in the UK With Non-Valvular Atrial Fibrillation Treated With Vitamin K Antagonists

Conditions
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Atrial Fibrillation

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria:- For the CPRD-HES cohort, patients will be included if they meet these criteria: Have CPRD data linked to HES Have an AF diagnosis (based on Read codes from CPRD or ICD-10 codes from HES) and have been treated with VKA during the study period -≥18 years old at index date CPRD acceptability quality criteria are present. For the CPRD cohort, patients will be included if they meet the following criteria: Have an Atrial Fibrillation (AF) diagnosis (based on Read codes from CPRD) and have been treated with VKAs during the study period ≥18 years old at index date CPRD acceptability quality criteria are present. Exclusion Criteria: For the two cohorts of interest, patients will be excluded if they meet the following criteria: Fewer than 12 months of computerised data available prior to the index date (in order to provide a minimum amount of computerised history and to avoid issues associated with updating records when a patient joins a practice). The date of start of computerized records will be the latter of the patient's date of registration with the practice or the practice's Up-to-Standard (UTS) date (when the practice is deemed to be contributing data of adequate quality) The practice is not UTS, or the patient is deemed unacceptable according to CPRD's quality criteria There is evidence of valvular disease, repair, or replacement before (ie, up to 12 months prior to the index date) or during the study period There are records of Novel anticoagulant (NOAC)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 100 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 |
| --- | --- |
| Vitamin K Antagonists<br>Vitamin K Antagonists dose as specified | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Impact of bleeding events on the risk of subsequent clinical events including subsequent bleeds assessed based on hazard ratios |  | Up to 24 months after initial treatment with VKA | 
| Impact of bleeding events on the rate of health-care resource utilization (HCRU) assessed based on incidence rate ratios |  | Up to 24 months after initial treatment with VKA | 
| Impact of bleeding events on the health-care costs in NVAF patients treated by VKAs assessed based on ratios of costs associated with number of bleeding events |  | Up to 24 months after initial treatment with VKA | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Variation of impact of bleeding events on clinical events, the rate of HCRU, and health-care costs over time following each bleeding event in NVAF patients treated by VKA |  | Upto 24 months after initial treatment with VKA | 
| Characteristics of NVAF patients newly treated with VKA who experience bleeding events |  | Up to 24 months after initial treatment with VKA | 
| Characteristics of NVAF patients newly treated with VKA who do not experience bleeding events |  | Up to 24 months after initial treatment with VKA |