Atrial fibrillation (AF) is an irregular heartbeat, or arrhythmia, that can lead to blood clots and stroke. AF is progressively more common with aging, is associated with substantial morbidity and mortality, and the risk of stroke is five-fold higher compared to patients without AF. This stroke risk is not the same for everyone and depends on having specific health characteristics, called risk factors. It is important to identity these stroke risk factors and categorize subgroups of patients who are likely to be at greater risk of stroke, as not all AF patients are the same and some may require different treatment than others. The commonly used CHA2DS2-VASc scoring system will be used to group patients based on their risk of stroke, then into corresponding smaller groups that require oral anticoagulant treatment to help reduce their individual risk of stroke.
Using data from the Clinical Practice Research Datalink (CPRD) database in the United Kingdom, we want to identify AF subgroups (sub-populations) of patients based on their level of risk of stroke using the CHA2DS2-VASc Score, as well as other comorbidities: hypertension, stroke, transient ischemic accident, venous thromboembolism, myocardial infarction, peripheral artery disease atherosclerosis and diabetes. We will explore the overlap between the various subgroups and the number of patients in each of these subgroups will help guide future research exploring the reduction of stroke risk.
Atrial Fibrillation (AF) is the most common sustained cardiac arrhythmia in adults, with prevalence between 2-4%, and increasing progressively with age. AF is associated with substantial morbidity and mortality, amplifies the risk of stroke five-fold compared to non-AF patients. The CHA2DS2-VASc Score permits stratification of AF patients based on several stroke risk factors, creating AF subgroups at different risk of stroke.
Using data from the UK databases CPRD Gold and Aurum, we propose to conduct a feasibility analysis to ascertain the size of the AF population receiving anticoagulation, stratified into different stroke risk subpopulations.
During the enrolment period (1/1/2012-30/06/2022), all individuals aged ≥18 years of age and registered for at least two years in CPRD database will constitute the source population and the day they meet these two criteria will be their entry date. We will identify two separate study cohorts: 1) Incident AF described as patients with a first ever AF recorded diagnosis after their entry date, a CHA2DS2VASc score ≥2 if male, or CHA2DS2VASc score ≥3 if female, and receiving oral anticoagulation (OAC) at the time of their AF first diagnosis, or 2) Prevalent AF described as patients with a AF recorded diagnosis before their entry date, a CHA2DS2VASc score ≥2 if male, or CHA2DS2VASc score ≥3 if female, and receiving oral anticoagulation (OAC) at the time of their entry date.
Objectives: To estimate absolute size of AF population classified in different subgroups based on CHA2DS2-VASc score, as well as to explore distribution of additional comorbidities and drug use in these subgroups. We will produce detailed descriptive analyses of demographic characteristics, cardiovascular risk scores, co-medications and comorbidities among the various AF sub-populations.
Based on findings, we may conduct additional research to explore the value of anticoagulant treatment in reducing stroke and other vascular events.
-Absolute number of prevalent and incident atrial fibrillation (AF) patients in CPRD GOLD and AURUM according to our operational definition (as listed in technical summary);
-Characterization of AF sub-populations based on CHA2DS2Vasc scores;
-Co-medications: oral anticoagulants and antiplatelets;
-Co-morbidities: hypertension, diabetes, stroke, transient ischemic accident, venous thromboembolism, myocardial infarction, peripheral arterial disease, atherosclerosis
Bersabeh Sile - Chief Investigator - Bayer AG
Luis Alberto Garcia Rodriguez - Corresponding Applicant - Centro Español de Investigaciones Farmacoepidemiológicas S.L. ( CEIFE S.L. )
Oscar Fernández Cantero - Collaborator - Centro Español de Investigaciones Farmacoepidemiológicas S.L. ( CEIFE S.L. )