Atrial Fibrillation

Trial Purpose

This population-based study will identify patients with rapid and irregular heartbeat which is not due to a fault with the heart valves (non-valvular atrial fibrillation) who initiate rivaroxaban, apixaban or warfarin as treatment for Stroke Prevention in Atrial Fibrillation (SPAF). Purpose of the study is to learn more about the safety and how well the drugs rivaroxaban, apixaban and warfarin work in patients appropriately and inappropriately receiving standard and reduced doses of each drug for reducing the risk of stroke in atrial fibrillation. Real world data from routine general practice stored in the primary care database in the UK, The Health Improvement Network (THIN), will be used for investigation.

- Patients with non-valvular atrial fibrillation
                - New users of rivaroxaban, apixaban or warfarin
                - At least one year enrollment with the general practice (GP)
                - One year since first health contact recorded in THIN prior to the first prescription of a study drug

- Patients with other recent indications of oral anticoagulant initiation
                - Individuals on more than one oral anticoagulant on the start date
                - Users of rivaroxaban apart from 15 / 20 mg daily dose
                - Users of apixaban apart from 5 / 10 mg daily dose