Oral anticoagulant switching in patients with atrial fibrillation: a long-term cohort study using population-level administrative data
摘要
Patient characteristics and clinical factors could necessitate switching between oral anticoagulants (OACs) for stroke prevention in atrial fibrillation (AF), a phenomenon whose causes and consequences are understudied.
AimOur objectives were to describe longitudinal patterns of OAC switching in patients with AF and to identify factors associated with switching.
MethodA cohort of adult AF patients were identified in Canadian administrative health data from 1996 to 2019. An OAC switch was defined as a change from one OAC to a different OAC with a gap of ≤ 30 days between prescriptions. Switch events were characterized, and factors associated with switches were analyzed using Cox regression.
ResultsThe cohort comprised 30,264 patients. One quarter experienced an OAC switch and 22% of those had ≥ 2 switch events. Vitamin K antagonist (VKA) to direct-acting oral anticoagulant (DOAC) was the most frequent switch type (63%). Switching to a previous OAC occurred commonly (19%-26%). A quarter of patients who switched from warfarin to a DOAC switched back to warfarin. Hospitalizations for AF, acute renal failure, vascular disease, gastrointestinal bleeding, and/or stroke ≤ 90 days before a switch had the highest hazards for VKA to DOAC switch. Hospitalizations for AF, stroke, major bleeding, vascular disease, and/or heart failure (HF) ≤ 90 days before a switch had the highest hazards for DOAC to VKA switch. Hospitalizations for AF, major bleeding, acute renal failure, vascular disease, stroke, and/or HF ≤ 90 days before a switch had the highest hazards for switch between DOACs.
ConclusionOAC switching is frequently required in AF patients, with many needing to return to a previously used agent. Switches may reflect an intention to maximize stroke prevention effectiveness and safety, but further research is needed to assess the risks and benefits of OAC switching.