Cost differences between oral anticoagulation therapies in atrial fibrillation patients

Abstract Background Direct oral anticoagulants (DOACs) have largely replaced warfarin as the primary choice of oral anticoagulation (OAC) in atrial fibrillation (AF) patients. This study uses a nationwide registry data set to compare the health and social care costs of AF patients using different OAC therapies. We studied how these costs were distributed among different care services in the year following AF onset and how the costs develop in time before and after AF diagnosis. Methods This study is a part of the Finnish AntiCoagulation in Atrial Fibrillation (FinACAF) research project, which includes data on patients with AF, combining registry data on primary and secondary care services as well as social services, drug purchases and laboratory data. We included all new-onset AF patients from 2011 to 2017 in Finland with an indication for OAC treatment. Patients were divided based on their first OAC purchase. Time in therapeutic range (TTR) values were assessed for warfarin patients, and they were divided into quartiles based on their TTR value. Standardized costs were determined for different health and social care contacts, accounting for hospital care, primary and ambulatory care, and long-term care. Drug costs were acquired from the Reimbursement for Prescription Medicines registry. Results A total of 130,745 patients (66,610 on warfarin, 32,996 on DOACs) were included. First-year total costs after onset of AF were €10,412 for rivaroxaban (n=13,320), €12,631 for apixaban (n=11,886), €10,706 for dabigatran (n=7,514) and €10,689 for edoxaban (n=366). Costs of care clustered near the diagnosis of AF (Figure 1). Costs for warfarin patients increased inversely with TTR, ranging from €10,945 in the highest TTR quartile (TTR over 82%) to €21,387 in the lowest (TTR under 57%). Average first-year costs for warfarin patients were €15,689, higher than DOAC patients by €3,058-€5,277 (Figure 2). Patients without any OAC had the highest first-year costs, €17,898. Patients with high risk of stroke had higher total costs both in patients using DOACS (€7,271 for patients with a CHA2DS2VA score of 1 vs €11,947 for patients with CHA2DS2VA 2+) and warfarin (€9,933 for CHA2DS2VA 1 vs €16,354 for CHA2DS2VA 2+). Drug costs averaged €1,541 for rivaroxaban, €1,659 for apixaban, €1,495 for dabigatran and €1,540 for edoxaban, and €986 warfarin users. Hospital care was the largest cost driver with 64% of total costs across the whole cohort, followed by primary care (19%), drug purchases (7%), social service costs (6%) and reimbursements for travel and private care (4%). Conclusions DOACs were superior to warfarin in a broad range of social and healthcare cost measures despite higher drug expenses. Patients on warfarin with low TTR and patients without any OAC had the highest cost of care.