Validation of Predictors of OAC Initiation Using EMR Data

Study Overview
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Brief Summary
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The objectives of this study are, first, to identify select clinical covariates from electronic medical records (EMR) that might be associated with initiation of oral anticoagulant medications (dabigatran or warfarin) in patients with non-valvular atrial fibrillation (NVAF) at risk for stroke; second, to quantify the association between EMR-based clinical characteristics and patterns of insurance claims; third, to assess the potential for unmeasured confounding in dabigatran vs warfarin comparative effectiveness and safety studies based on administrative claims databases.

Official Title
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Validation of Predictors for Oral Anticoagulant Medication Choice Using EMR Data

Conditions
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Atrial Fibrillation

Intervention / Treatment
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* Drug: Dabigatran etexilate
* Drug: Warfarin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: First dispensing of warfarin or dabigatran between October 2010 and December 2014 Diagnosis of atrial fibrillation ≥ 12 months enrolment in the database preceding the date of the first dispensing Age ≥ 18 Congestive Heart Failure, Hypertension, Age > 75, Diabetes Mellitus, Prior Stroke or Transient Ischemic Attack, Vascular Disease (CHA2DS2-VASc) score ≥ 1 Exclusion Criteria: Prior use of oral anticoagulation Evidence of valvular atrial fibrillation Missing or ambiguous age or sex information Patients with a nursing home stay during baseline

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 |
| --- | --- |
| Dabigatran etexilate<br>NVAF patients initiating dabigatran etexilate | Drug: Dabigatran etexilate<br>* observed upto 12 months<br>* Other names: MICARDIS, PRITOR, TELMISARTAN;|
| Warfarin<br>NVAF patients initiating warfarin | Drug: Warfarin<br>* Observed upto 12 months<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Patients With Obesity | Percentage of patients with obesity; where obesity is defined as obese, not-obese based on note of obesity or recorded body mass index (BMI) > 30 in the electronic medical records (EMR). The results are provided before and after propensity score (PS) matching. Before PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR whose data were available; After PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR, 1:1 propensity score matched, whose data were available. | Up to 12 months | 
| Percentage of Patients Smoking | Percentage of patients with current/past smoking in the electronic medical records (EMR) are presented. The results are provided before and after propensity score (PS) matching. Before PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR whose data were available; After PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR, 1:1 propensity score matched, whose data were available. | Up to 12 months | 
| Percentage of Patients With Alcohol Consumption | Percentage of patients with alcohol consumption in the electronic medical records (EMR) are presented. The patients with light to moderate, heavy and unknown quantity of alcohol consumption are considered. The results are provided before and after propensity score (PS) matching. Before PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR whose data were available; After PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR, 1:1 propensity score matched, whose data were available. | Up to 12 months | 
| Percentage of Patients With Abnormal Renal Function | Percentage of patients with abnormal renal function; defined as Any note of: Dialysis, renal transplant Serum Creatinine >1.3 Milligrams per Deciliter (mg/dL) in the electronic medical records (EMR). Response was considered to be truly absent if not recorded in the EMR. The results are provided before and after propensity score (PS) matching. Before PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR whose data were available; After PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR, 1:1 propensity score matched, whose data were available. | Up to 12 months | 
| Percentage of Patients With Bleeding History or Predisposition | Percentage of patients with bleeding history or predisposition is presented, defined as any note of major bleeding requiring hospitalization or blood transfusion or causing a decrease in hemoglobin level of > 2 gram per liter (g/L) in the electronic medical records (EMR). Response was considered to be truly absent if not recorded in the EMR. The results are provided before and after propensity score (PS) matching. Before PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR whose data were available; After PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR, 1:1 propensity score matched, whose data were available. | Up to 12 months | 
| EMR Characteristic: Renal Function - Glomerular Filtration Rate (GFR) | EMR characteristic: Renal function - Glomerular Filtration Rate (GFR). Estimated GFR closest to index dispensing. The results are provided before and after propensity score (PS) matching. Before PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR whose data were available; After PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR, 1:1 propensity score matched, whose data were available. | Up to 12 months | 
| EMR Characteristic: Serum Creatinine | EMR characteristic: Serum Creatinine closest to index dispensing. The results are provided before and after propensity score (PS) matching. Before PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR whose data were available; After PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR, 1:1 propensity score matched, whose data were available. | Up to 12 months | 
| Percentage of Patients With Abnormal Liver Function | Percentage of patients with abnormal liver function; defined as Any note of: Liver disease, cirrhosis, Active hepatitis C, Active hepatitis B, Active hepatitis A, aspartate transaminase/alanine transaminase (AST/ALT) >3 times upper limit of normal in the electronic medical records (EMR). Absence of any note would be considered as absence of the disease. Response was considered to be truly absent if not recorded in the EMR. The results are provided before and after propensity score (PS) matching. Before PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR whose data were available; After PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR, 1:1 propensity score matched, whose data were available. | Up to 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| EMR Characteristic: Duration of Atrial Fibrillation | EMR characteristic: Duration of atrial fibrillation (Years / months prior to initiation of Dabigatran / Warfarin). Duration is defined as number of months prior to index date for the earliest note. The results are provided before and after propensity score (PS) matching. Before PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR whose data were available; After PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR, 1:1 propensity score matched, whose data were available. | Up to 12 months | 
| EMR Characteristic: History of Adherence: Non-adherent/Adherent | EMR characteristic: History of adherence: non-adherent/adherent. | Up to 12 months | 
| EMR Characteristic: History/Duration of Hypertension | EMR characteristic: History/duration of hypertension. Any note of: Hypertension systolic blood pressure (SBP) >120 millimeters of mercury (mmHg) Hypertension drugs. Duration is defined as number of months prior to index date for the earliest note. The results are provided before and after propensity score (PS) matching. Before PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR whose data were available; After PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR, 1:1 propensity score matched, whose data were available. | Up to 12 months | 
| Percentage of Patients With Uncontrolled Hypertension | Percentage of patients with uncontrolled hypertension; defined as SBP >160 mmHg using the most recent information prior to index date in the electronic medical records (EMR). The results are provided before and after propensity score (PS) matching. Before PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR whose data were available; After PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR, 1:1 propensity score matched, whose data were available. | Up to 12 months | 
| EMR Characteristic: History/Duration of Congestive Heart Failure (CHF) | EMR characteristic: History/duration of Congestive Heart Failure (CHF). Duration is defined as number of months prior to index date for the earliest note. Response was considered to be truly absent if not recorded in the EMR. The results are provided before and after propensity score (PS) matching. Before PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR whose data were available; After PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR, 1:1 propensity score matched, whose data were available. | Up to 12 months | 
| Percentage of Patients With Prior Transient Ischemic Attack | Percentage of patients with any note of prior transient ischemic attack in the electronic medical records (EMR). Response was considered to be truly absent if not recorded in the EMR. The results are provided before and after propensity score (PS) matching. Before PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR whose data were available; After PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR, 1:1 propensity score matched, whose data were available. | Up to 12 months | 
| Percentage of Patients With Diabetes | Percentage of patients with any note of diabetes type I or II in the electronic medical records (EMR) is presented. Response was considered to be truly absent if not recorded in the EMR. The results are provided before and after propensity score (PS) matching. Before PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR whose data were available; After PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR, 1:1 propensity score matched, whose data were available. | Up to 12 months | 
| Percentage of Patients With Hyperlipidemia | Percentage of patients with hyperlipidemia is presented, defined as any note of hyperlipidemia, dyslipidemia or Low Density Lipoprotein (LDL) >130 mg/dl in the electronic medical records (EMR). Response was considered to be truly absent if not recorded in the EMR. The results are provided before and after propensity score (PS) matching. Before PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR whose data were available; After PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR, 1:1 propensity score matched, whose data were available. | Up to 12 months | 
| EMR Characteristic: Hypertension, Abnormal Liver/Renal Function, Stroke, Bleeding History or Predisposition, Labile International Normalized Ratio, Elderly, Drugs/Alcohol Usage (HAS-BLED) Score | EMR characteristic: HAS-BLED Score. HAS-BLED score is calculated by adding the specified points for each of the conditions listed below. Hypertension (uncontrolled), Abnormal renal and liver function, Stroke, Bleeding history or predisposition (anemia), Labile International Normalized Ratio (INR), Elderly, Drugs or alcohol (1 point each). Labile INR is defined as as the most recent INR <2 or >3 prior to cohort entry. Conditions are considered to be truly absent if not recorded in the EMR. The results are provided before and after propensity score (PS) matching. Before PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR whose data were available; After PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR, 1:1 propensity score matched, whose data were available. | Up to 12 months | 
| Percentage of Patients With Use of Antiplatelets or Non-steroidal Anti-inflammatory Drugs | Percentage of patients with use of antiplatelets or non-steroidal anti-inflammatory drugs (NSAIDs). Includes use of aspirin, clopidogrel, prasugrel, ticagrelor or NSAIDs (within 1 month or on the index date) in the electronic medical records (EMR). Response was considered to be truly absent if not recorded in the EMR. The results are provided before and after propensity score (PS) matching. Before PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR whose data were available; After PS matching: all patients meeting inclusion/exclusion criteria successfully linked to EMR, 1:1 propensity score matched, whose data were available. | Up to 1 month |