Aims
Little is known about the effects of mental health conditions (MHCs) on the utilization of oral anticoagulation (OAC) therapy in atrial fibrillation (AF) patients. We aimed to assess whether MHCs affect initiation of OAC therapy among AF patients with special focus on non-vitamin K antagonist oral anticoagulants (NOACs).

Methods and results
The Finnish AntiCoagulation in Atrial Fibrillation (FinACAF) registry included all 239 222 patients diagnosed with incident AF during 2007–18 in Finland identified from national registries covering primary to tertiary care and drug purchases. Patients with previous depression, bipolar disorder, anxiety disorder, or schizophrenia diagnosis or a fulfilled psychiatric medication prescription within the year preceding the AF diagnosis were classified to have any MHC. The main outcome was OAC initiation, defined as first fulfilled OAC prescription after AF diagnosis. The patients’ mean age was 72.7 years and 49.8% were female. The prevalence of any MHC was 19.9%. A lower proportion of patients with any MHC compared with those without MHCs were initiated on OAC therapy (64.9% vs. 73.3%, P < 0.001). Any MHC was associated with lower incidence of OAC initiation [adjusted subdistribution hazard ratio (aSHR) 0.867; 95% confidence interval (CI) 0.856–0.880], as were depression (aSHR 0.868; 95% CI 0.856–0.880), bipolar disorder (aSHR 0.838; 95% CI 0.824–0.852), anxiety disorder (aSHR 0.840; 95% CI 0.827–0.854), and schizophrenia (aSHR 0.838; 95% CI 0.824–0.851), during the entire follow-up. Any MHC remained associated with impaired incidence of OAC initiation also in the NOAC era during 2015–18 (aSHR 0.821; 95% CI 0.805–0.837).

Conclusion
MHCs are common among AF patients, and they are associated with a lower rate of OAC initiation even during the NOAC era.