Non-interventional, Retrospective Cohort Study to Explore OAC Treatment in Korea

Study Overview
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Brief Summary
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The primary purpose of this study is to evaluate comparative effectiveness and safety outcomes of therapies to prevent thromboembolic events in patients with nonvalvular atrial fibrillation by using Korean nationwide health claims database.

Official Title
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THE REAL WORLD EVIDENCE ON TREATMENT PATTERNS, EFFECTIVENESS, AND SAFETY OF DRUGS FOR STROKE PREVENTION IN NONVALVULAR ATRIAL FIBRILLATION PATIENTS IN KOREA

Conditions
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Atrial Fibrillation

Intervention / Treatment
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* Drug: Apixaban
* Drug: Dabigatran
* Drug: Rivaroxaban
* Drug: warfarin
* Drug: Antiplatelets


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: Patients aged 18 years or older on the index date Patients had ≥1 medical claim for AF (refer to Table 1) before or on the index date with at least one hospitalization or at least two outpatient visits: Patients prescribed aspirin, warfarin, or NOACs during intake period (from July 1, 2015 to November 30, 2016) Exclusion criteria: Patients meeting any of the following criteria will not be included in the study. Medical claims indicating diagnosis or procedure for hip/knee replacement surgery within 6 weeks prior to index date Medical claims indicating a diagnosis code indicative of rheumatic mitral valvular heart disease, mitral valve stenosis during the 12-month baseline period (Valvular AF / Prosthetic heart valves) Medical claims indicating a diagnosis code of VTE (Venous thromboembolism) during the 12-month baseline period Medical claims indicating a diagnosis or procedure code of transient AF, or cardiac surgery during the 12-month baseline period (Thyrotoxicosis, Hypertrophic cardiomyopathy, Elective defibrillation, radiofrequency ablation, or left atrial appendage occlusion) Medical claims indicating a diagnosis code of other conditions during the 12-month baseline period (End-stage chronic kidney disease / Kidney transplant / Dialysis / Pericarditis) For the comparison of NOAC versus NOAC, and NOAC versus warfarin, patients with any OACs (apixaban, dabigatran, rivaroxaban, or warfarin) in the pre-index period (from 1 year prior to the day before index date) For the comparison of NOAC versus aspirin, patients with following medications in the pre-index period (from 1 year prior to the day before index date) NOAC user: OACs (apixaban, dabigatran, rivaroxaban, warfarin) Aspirin user: none

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 |
| --- | --- |
| Patients prescribed apixaban<br> | Drug: Apixaban<br>* Treatment for NVAF patients<br>|
| Patients prescribed dabigatran<br> | Drug: Dabigatran<br>* Treatment for NVAF patients<br>|
| Patients prescribed rivaroxaban<br> | Drug: Rivaroxaban<br>* Treatment for NVAF patients<br>|
| Patients prescribed warfarin<br> | Drug: warfarin<br>* Treatment for NVAF patients<br>|
| Patients prescribed antiplatelet<br> | Drug: Antiplatelets<br>* Treatment for NVAF patients<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Event Rate of Stroke/Systemic Embolism Requiring Hospitalization: NOAC Versus Warfarin Analysis | Event rate was defined as number of events divided by 100 participant-years. Hemorrhagic stroke, ischemic stroke and systemic embolism requiring hospitalization identified using hospital claims which had hemorrhagic, ischemic stroke or systemic embolism Korean standard classification of diseases (KCD) code, whichever came first (first occurred event used). KCD code: hemorrhagic stroke = I60-62, I690-692; ischemic stroke = G459, I63, I693; systemic embolism = I74. Hospitalization and brain CT/MRI codes were used for ischemic stroke, hemorrhagic stroke.Hospitalization and any CT/MRI codes were used for systemic embolism. Index date = the first prescription date of study drugs during intake duration. Participants were identified as NOAC user or Warfarin user depending on the date when they first used NOAC or Warfarin during intake duration. | Maximum of 1 year 4 months (From 1-July-2015 to 30-November-2016) | 
| Event Rate of Stroke/Systemic Embolism Requiring Hospitalization: NOAC Versus NOAC Analysis | Event rate was defined as number of events divided by 100 participant-years. Hemorrhagic stroke, ischemic stroke and systemic embolism requiring hospitalization identified using hospital claims which had hemorrhagic, ischemic stroke or systemic embolism Korean standard classification of diseases (KCD) code, whichever came first (first occurred event used). KCD code: hemorrhagic stroke = I60-62, I690-692; ischemic stroke = G459, I63, I693; systemic embolism = I74. Hospitalization and brain CT/MRI codes were used for ischemic stroke, hemorrhagic stroke.Hospitalization and any CT/MRI codes were used for systemic embolism. Index date = the first prescription date of study drugs during intake duration. | Maximum of 1 year 4 months (From 1-July-2015 to 30-November-2016) | 
| Event Rate of Major Bleeding Requiring Hospitalization: NOAC Versus Warfarin Analysis | Event rate: number of events divided by 100 participant-years. Intracranial hemorrhage (ICH), gastrointestinal (GI) bleeding and other bleeding requiring hospitalization identified using hospital claims which had ICH, GI and other bleeding KCD code whichever came first (first occurred event used). KCD code: ICH = I60-62, I690-92, S064-66, S068; GI bleeding = I850, I983, K2211, K226, K228, K250, K252, K254, K256, K260, K262, K264, K266, K270, K272, K274, K276, K280, K282, K284, K286, K290, K3181, K5521, K625, K920, K921, K922; other bleeding = D62,H448,H3572,H356,H313,H210,H113,H052,H470,H431,I312,N020-N029,N421,N831,N857,N920,N923,N930,N938-939,M250,R233,R040-042,R048-049,T792,T810,N950,R310, R311, R318, R58, T455, Y442, D683). Brain CT/MRI codes were used for ICH only. Index date= first prescription date of study drugs during intake duration. Participants were identified as NOAC user/Warfarin user depending on the date when they first used NOAC or Warfarin during intake duration. | Maximum of 1 year 4 months (From 1-July-2015 to 30-November-2016) | 
| Event Rate of Major Bleeding Requiring Hospitalization: NOAC Versus NOAC Analysis | Event rate was defined as number of events divided by 100 participant-years. Intracranial hemorrhage (ICH), gastrointestinal (GI) bleeding and other bleeding requiring hospitalization identified using hospital claims which had ICH, GI and other bleeding KCD code whichever came first (first occurred event used). KCD code: ICH = I60-62, I690-92, S064-66, S068; GI bleeding = I850, I983, K2211, K226, K228, K250, K252, K254, K256, K260, K262, K264, K266, K270, K272, K274, K276, K280, K282, K284, K286, K290, K3181, K5521, K625, K920, K921, K922; other bleeding = D62, H448, H3572, H356, H313, H210, H113, H052, H470, H431, I312, N020-N029, N421, N831, N857, N920, N923, N930, N938-939, M250, R233, R040-042, R048-049, T792, T810, N950, R310, R311, R318, R58, T455, Y442, D683). Brain CT/MRI codes were used for ICH only. Index date = the first prescription date of study drugs during intake duration. | Maximum of 1 year 4 months (From 1-July-2015 to 30-November-2016) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Event Rate of Hemorrhagic Stroke Requiring Hospitalization: NOAC Versus Warfarin Analysis | Event rate was number of events divided by 100 participant-years for first occurrence of hemorrhagic stroke events after index date was reported. Hemorrhagic stroke requiring hospitalization was identified using hospital claims which had a hemorrhagic stroke KCD code (I60-62, I690-692). For hemorrhagic stroke, hospitalization and brain CT or MRI codes were also required. Index date = the first prescription date of study drugs during intake duration. Participants were identified as NOAC user or Warfarin user depending on the date when they first used NOAC or Warfarin during intake duration. | Maximum of 1 year 4 months (From 1-July-2015 to 30-November-2016) | 
| Event Rate of Hemorrhagic Stroke Requiring Hospitalization: NOAC Versus NOAC Analysis | Event rate was defined as number of events divided by 100 participant-years for first occurrence of hemorrhagic stroke events after index date was reported. Hemorrhagic stroke requiring hospitalization was identified using hospital claims which had a hemorrhagic stroke KCD code (I60-62, I690-692). For hemorrhagic stroke, hospitalization and brain CT or MRI codes were also required. Index date = the first prescription date of study drugs during intake duration. | Maximum of 1 year 4 months (From 1-July-2015 to 30-November-2016) | 
| Event Rate of Ischemic Stroke Requiring Hospitalization: NOAC Versus Warfarin Analysis | Event rate was defined as number of events divided by 100 participant-years for first occurrence of ischemic stroke events after index date was reported. Ischemic stroke requiring hospitalization was identified using hospital claims which had ischemic stroke KCD code (G459, I63, and I693). For ischemic stroke, hospitalization and brain CT or MRI codes were also required. Index date = the first prescription date of study drugs during intake duration. Participants were identified as NOAC user or Warfarin user depending on the date when they first used NOAC or Warfarin during intake duration. | Maximum of 1 year 4 months (From 1-July-2015 to 30-November-2016) | 
| Event Rate of Ischemic Stroke Requiring Hospitalization: NOAC Versus NOAC Analysis | Event rate was defined as number of events divided by 100 participant-years for first occurrence of ischemic stroke events after index date was reported. Ischemic stroke requiring hospitalization was identified using hospital claims which had ischemic stroke KCD code (G459, I63, and I693). For ischemic stroke, hospitalization and brain CT or MRI codes were also required. Index date = the first prescription date of study drugs during intake duration. | Maximum of 1 year 4 months (From 1-July-2015 to 30-November-2016) | 
| Event Rate of Systemic Embolism Requiring Hospitalization: NOAC Versus Warfarin Analysis | Event rate was defined as number of events divided by 100 participant-years for first occurrence of systemic embolism. Systemic embolism requiring hospitalization was identified using hospital claims which had systemic embolism KCD code = I74. For systemic embolism, hospitalization and any CT or MRI codes was used. Index date = the first prescription date of study drugs during intake duration. Participants were identified as NOAC user or Warfarin user depending on the date when they first used NOAC or Warfarin during intake duration | Maximum of 1 year 4 months (From 1-July-2015 to 30-November-2016) | 
| Event Rate of Systemic Embolism Requiring Hospitalization: NOAC Versus NOAC Analysis | Event rate was defined as number of events divided by 100 participant-years for first occurrence of systemic embolism. Systemic embolism requiring hospitalization was identified using hospital claims which had systemic embolism KCD code = I74. For systemic embolism, hospitalization and any CT or MRI codes was used. Index date= the first prescription date of study drugs during intake duration. | Maximum of 1 year 4 months (From 1-July-2015 to 30-November-2016) | 
| Event Rate of Gastrointestinal (GI) Bleeding Requiring Hospitalization: NOAC Versus Warfarin Analysis | Event rate was defined as number of events divided by 100 participant-years for first occurrence of GI bleeding events after index date was reported. GI bleeding requiring hospitalization was identified using hospital claims which had a GI bleeding KCD code (I850, I983, K2211, K226, K228, K250, K252, K254, K256, K260, K262, K264, K266, K270, K272, K274, K276, K280, K282, K284, K286, K290, K3181, K5521, K625, K920, K921, K922). Index date = the first prescription date of study drugs during intake duration. Participants were identified as NOAC user or Warfarin user depending on the date when they first used NOAC or Warfarin during intake duration. | Maximum of 1 year 4 months (From 1-July-2015 to 30-November-2016) | 
| Event Rate of Gastrointestinal (GI) Bleeding Requiring Hospitalization: NOAC Versus NOAC Analysis | Event rate was defined as number of events divided by 100 participant-years for first occurrence of GI bleeding events after index date was reported. GI bleeding requiring hospitalization was identified using hospital claims which had a GI bleeding KCD code (I850, I983, K2211, K226, K228, K250, K252, K254, K256, K260, K262, K264, K266, K270, K272, K274, K276, K280, K282, K284, K286, K290, K3181, K5521, K625, K920, K921, K922). Index date = the first prescription date of study drugs during intake duration. | Maximum of 1 year 4 months (From 1-July-2015 to 30-November-2016) | 
| Event Rate of Intracranial Hemorrhage Requiring Hospitalization: NOAC Versus Warfarin Analysis | Event rate was defined as number of events divided by 100 participant-years for first occurrence of intracranial hemorrhage events after index date was reported. Intracranial hemorrhage requiring hospitalization was identified using hospital claims which had an intracranial hemorrhage KCD code (I60, I61, I62, I690, I691, I692, S064, S065, S066, and S068) and brain CT or MRI codes. Index date = the first prescription date of study drugs during intake duration. Participants were identified as NOAC user or Warfarin user depending on the date when they first used NOAC or Warfarin during intake duration. | Maximum of 1 year 4 months (From 1-July-2015 to 30-November-2016) | 
| Event Rate of Intracranial Hemorrhage Requiring Hospitalization: NOAC Versus NOAC Analysis | Event rate was defined as number of events divided by 100 participant-years for first occurrence of intracranial hemorrhage events after index date was reported. Intracranial hemorrhage requiring hospitalization was identified using hospital claims which had an intracranial hemorrhage KCD code (I60, I61, I62, I690, I691, I692, S064, S065, S066, and S068) and brain CT or MRI codes. Index date = the first prescription date of study drugs during intake duration. | Maximum of 1 year 4 months (From 1-July-2015 to 30-November-2016) | 
| Event Rate of Other Bleeding Requiring Hospitalization: NOAC Versus Warfarin Analysis | Event rate was defined as number of events divided by 100 participant-years for first occurrence of other bleeding events after index date was reported. Other bleeding requiring hospitalization was identified using hospital claims which had other bleeding KCD code (D62, H448, H3572, H356, H313, H210, H113, H052, H470, H431, I312, N020-N029, N421, N831, N857, N920, N923, N930, N938, N939, M250, R233, R040, R041, R042, R048, R049, T792, T810, N950, R310, R311, R318, R58, T455, Y442, D683). Index date = the first prescription date of study drugs during intake duration. Participants were identified as NOAC user or Warfarin user depending on the date when they first used NOAC or Warfarin during intake duration. | Maximum of 1 year 4 months (From 1-July-2015 to 30-November-2016) | 
| Event Rate of Other Bleeding Requiring Hospitalization: NOAC Versus NOAC Analysis | Event rate was defined as number of events divided by 100 participant-years for first occurrence of other bleeding events after index date was reported. Other bleeding requiring hospitalization was identified using hospital claims which had other bleeding KCD code (D62, H448, H3572, H356, H313, H210, H113, H052, H470, H431, I312, N020-N029, N421, N831, N857, N920, N923, N930, N938, N939, M250, R233, R040, R041, R042, R048, R049, T792, T810, N950, R310, R311, R318, R58, T455, Y442, D683). Index date = the first prescription date of study drugs during intake duration. | Maximum of 1 year 4 months (From 1-July-2015 to 30-November-2016) |