Non-Interventional Study Describing Direct Costs Related to Anti-coagulation Treatment

Study Overview
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Brief Summary
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To describe the direct costs related to warfarin/apixaban treatment

Detailed Description
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To describe the direct costs related to warfarin/apixaban treatment during the first 6 months of the secondary stroke prevention in NVAF patients.

Official Title
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Non-interventional Study Describing Direct Costs Related to Anticoagulation Treatment in Patients With Nonvalvular Atrial Fibrillation (NVAF) in Secondary Stroke Prevention Prescribed Apixaban or Warfarin Treatment

Conditions
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Atrial Fibrillation

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosis of non-valvular atrial fibrillation (NVAF); New initiation of anticoagulation therapy (apixaban or warfarin) due to the ischemic event (stroke/TIA) meaning patients previously not anticoagulated due to diagnosis of NVAF; Indication to anticoagulation therapy as a secondary stroke prevention within 7 to 30 days after the stroke/TIA event; Apixaban arm: genetically determined higher sensitivity to warfarin; Patients whose status allowed oral treatment with apixaban/warfarin; Age ≥ 18; Access to patient´s records of the first 6 months of the warfarin/apixaban treatment. Exclusion Criteria: Diagnosis of valvular disease; Treatment with other anticoagulants in previous 6 months due to other the NVAF indication; Treatment or prophylaxis of deep vein thrombosis or pulmonary embolism; Contraindications according SmPC of Eliquis

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 |
| --- | --- |
| Non-valvular Atrial Fibrillation (NVAF) on warfarin<br>The study follows two cohorts of Non-valvular Atrial Fibrillation (NVAF) patients, who used warfarin as a secondary stroke/TIA prevention. | |
| Non-valvular Atrial Fibrillation (NVAF) on apixaban<br>The study follows two cohorts of Non-valvular Atrial Fibrillation (NVAF) patients, who used apixaban as a secondary stroke/TIA prevention. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| CHA2-DS2-VASc Score at Baseline | CHA2DS2-VASc scoring scale was used to estimate the risk of stroke and systemic emboli in participants with NVAF. CHA2DS2-VASc score was calculated based on 8 risk factors (age 65-74 years, age >=75 years, sex category, i.e. female sex, congestive heart failure history, hypertension history, stroke/TIA/thromboembolism history, vascular disease history and diabetes mellitus history). Total CHA2DS2-VASc score ranged from 0-9 where 0= low risk and 9= high risk of stroke. | Baseline (from retrospective data retrieved in the study) | 
| HAS-BLED Score at Baseline | HAS-BLED scoring scale was used to estimate the risk of bleeding. HAS-BLED score was calculated based on 9 risk factors (hypertension, renal disease, liver disease, stroke history, prior major bleeding or predisposition to bleeding, labile international normalized ratio (INR), age >65 years, medication usage predisposing to bleeding and alcohol use). Total HAS-BLED score ranged from 0 to 9 where 0 = low risk and >=3 = high risk of bleed. | Baseline (from retrospective data retrieved in the study) | 
| CHA2-DS2-VASc Score at Month 6 | CHA2DS2-VASc scoring scale was used to estimate the risk of stroke and systemic emboli in participants with NVAF. CHA2DS2-VASc score was calculated based on 8 risk factors (age 65-74 years, age >=75 years, sex category i.e. female sex, congestive heart failure history, hypertension history, stroke/TIA/thromboembolism history, vascular disease history and diabetes mellitus history). Total CHA2DS2-VASc score ranged from 0-9 where 0= low risk and 9= high risk of stroke. | Month 6 (from retrospective data retrieved in the study) | 
| HAS-BLED Score at Month 6 | HAS-BLED scoring scale was used to estimate the risk of bleeding. HAS-BLED score was calculated based on 9 risk factors (hypertension, renal disease, liver disease, stroke history, prior major bleeding or predisposition to bleeding, labile international normalized ratio (INR), age >65 years, medication usage predisposing to bleeding and alcohol use). Total HAS-BLED score ranged from 0 to 9 where 0 = low risk and >=3 = high risk of bleed. | Month 6 (from retrospective data retrieved in the study) | 
| Percentage of Participants Categorized According to Number of Outpatient Visits During First 6 Months of Treatment | In this outcome measure, percentage of participants were categorized according to number of outpatient visits from 0 to 5. | Up to first 6 months of treatment (from retrospective data retrieved in the study) | 
| Cost of Outpatient Visits During First 6 Months of Treatment | Costs of outpatient visits were calculated for the first 6 months of treatment as the number of visits multiplied by the cost of the visit (450.0 Czech koruna [CZK] per visit). Costs were calculated based on the number of outpatient visits during the treatment. | Up to first 6 months of treatment (from retrospective data retrieved in the study) | 
| Percentage of Participants Categorized According to Number of International Normalized Ratios (INR) Measurements During First 6 Months of Treatment | INR was defined as the ratio of the participant's prothrombin time and the normal mean prothrombin time. Prothrombin time defined as a time taken by the blood to clot in participants receiving oral anticoagulant medication. In this outcome measure, percentage of participants were categorized according to number of INR measurements included zero (0), 1 to 9, 10 to 19 and greater than or equal to (>=) 20. | Up to first 6 months of treatment (from retrospective data retrieved in the study) | 
| Cost of INR Measurements During First 6 Months of Treatment | INR was defined as the ratio of the participant's prothrombin time and the normal mean prothrombin time. Prothrombin time defined as a time taken by the blood to clot in participants receiving oral anticoagulant medication. Costs related to INR measurements, were calculated for the period of 6 months as the number of INR measurements multiplied by the cost of the INR measurement (213.0 CZK per measurement). Costs were based on the expenditure of total number of INR measurements during first 6-month treatment. | Up to first 6 months of treatment (from retrospective data retrieved in the study) | 
| Dosage of Warfarin and Apixaban at the Initiation of the Treatment | In this outcome measure, dosage of apixaban and warfarin used at the initiation of treatment was reported. | Baseline (from retrospective data retrieved in the study) | 
| Dosage of Warfarin and Apixaban During First 6 Months of Treatment | In this outcome measure, dosage of apixaban and warfarin used during first 6 months of treatment was reported. | Up to first 6 months of treatment (from retrospective data retrieved in the study) | 
| Cost of Medication During First 6 Months of Treatment | In this outcome measure, cost of medication, i.e., costs of apixaban and warfarin were based on the dosage of active substance and were calculated for the first 6 months of treatment (daily cost times 182.4 days), regardless of how long the individual participant treated was reported. | Up to first 6 months of treatment (from retrospective data retrieved in the study) | 
| Percentage of Participants Categorized According to Number of Hospital Admissions | In this outcome measure, percentage of participants were categorized according to number of hospital admissions from 0 to 3 were reported. | Up to first 6 months of treatment (from retrospective data retrieved in the study) | 
| Cost of Hospital Admissions During First 6 Months of Treatment | In this outcome measure, costs of hospital admissions were based on the number of hospital admissions during the treatment period by considering the reason for hospitalization. If the reason for admission was not related to the recorded event (ischemic, hemorrhagic, or other adverse event), or the participant experienced none of these events, the cost of hospitalization was calculated as the number of days multiplied by the cost per a day of hospitalization (1898.2 CZK per day). | Up to first 6 months of treatment (from retrospective data retrieved in the study) | 
| Percentage of Participants Categorized According to Number of Diagnostic Procedures | In this outcome measure, percentage of participants were categorized according to number of diagnostic procedures. | Up to first 6 months of treatment (from retrospective data retrieved in the study) | 
| Percentage of Participants Categorized According to Type of Ischemic Events During First 6 Months of Treatment | In this outcome measure, percentage of participants were categorized according to type of ischemic events which included cardiac ischemia and stroke/TIA. | Up to first 6 months of treatment (from retrospective data retrieved in the study) | 
| Cost of Ischemic Events During First 6 Months of Treatment | Costs of ischemic events (cardiac ischemia and stroke/TIA) included expenditure of diagnosis, medication, outpatient visits and hospitalization were reported based on the recorded number of ischemic events during the first 6 months of treatment. | Up to first 6 months of treatment (from retrospective data retrieved in the study) | 
| Percentage of Participants Categorized With Major Hemorrhagic Events During First 6 Months of Treatment | In this outcome measure, percentage of participants with major hemorrhagic events which included intracranial bleeding was reported. | Up to first 6 months of treatment (from retrospective data retrieved in the study) | 
| Percentage of Participants Categorized According to Type of Minor Hemorrhagic Events During First 6 Months of Treatment | In this outcome measure, percentage of participants were categorized according to type of minor hemorrhagic events which included epistaxis, gastrointestinal (GI) bleeding, muscle hematomas and intraparenchymal hematoma of the lower lobe. | Up to first 6 months of treatment (from retrospective data retrieved in the study) | 
| Cost of Major Hemorrhagic Events During First 6 Months of Treatment | Costs of major hemorrhagic events (intracranial bleeding) included expenditure of diagnosis, medication, outpatient visits and hospitalization were reported based on the recorded number of major hemorrhagic events during the first 6 months of treatment. | Up to first 6 months of treatment (from retrospective data retrieved in the study) | 
| Cost of Minor Hemorrhagic Events During First 6 Months of Treatment | Costs of minor hemorrhagic events (epistaxis, GI bleeding, muscle hematomas and intraparenchymal hematoma of the lower lobe) included expenditure of diagnosis, medication, outpatient visits and hospitalization were reported based on the recorded number of minor hemorrhagic events during the first 6 months of treatment. | Up to first 6 months of treatment (from retrospective data retrieved in the study) | 
| Number of Participants With Other Adverse Events During First 6 Months of Treatment | An adverse event (AE) was any untoward medical occurrence in a participant who received study drug without regard to possibility of causal relationship. Other adverse events included all events other than ischemic, major and minor hemorrhagic events. | Up to first 6 months of treatment (from retrospective data retrieved in the study) | 
| Cost of Other Adverse Events During First 6 Months of Treatment | Costs of other adverse events included expenditure of diagnosis, medication, outpatient visits and hospitalization were reported based on the number of other adverse events during the treatment. | Up to first 6 months of treatment (from retrospective data retrieved in the study) | 
| Percentage of Participants Who Died (Treatment-Related) During First 6 Months of Treatment | In this outcome measure, percentage of participants who died due to the given treatment were reported. | Up to first 6 months of treatment (from retrospective data retrieved in the study) |