Risk of suicide in patients with atrial fibrillation receiving different oral anticoagulants: a nationwide analysis using target trial emulation framework

Background: The suicide risk in patients with atrial fibrillation receiving novel oral anticoagulants or warfarin has not been evaluated in real-world practice. Moreover, reducing vitamin K levels may increase the suicide risk, underscoring the importance of selecting appropriate oral anticoagulants to prevent unintended outcomes. Therefore, we aimed to evaluate the association between different types of oral anticoagulants and the risk of attempted and completed suicide among patients with atrial fibrillation. Methods: This nationwide study retrieved data from Taiwan's National Health Insurance Research Database from 2012 to 2020. This study included patients with atrial fibrillation aged 20 years and older who newly received oral anticoagulant treatment, and who had no contraindications for NOACs and no history of suicide-related events. The main outcomes were suicide-related outcomes, including attempted suicide and completed suicide. This study employed the target trial emulation framework to improve the causal inference for the observed association. Results: A total of 103,768 (71.74%) patients taking NOACs and 40,877 (28.26%) patients taking warfarin were included in this study. Compared to those receiving warfarin, patients receiving NOACs were associated with a lower risk of suicide-related outcomes (HR, 0.82; 95% CIs, 0.69–0.96). Conclusions: The findings of this cohort study suggested that patients receiving NOACs were associated with a lower risk of suicidal attempts but similar risk of complete suicide, compared to those receiving warfarin. Considering the risk of suicide, NOACs could be the preferred anticoagulants for patients with atrial fibrillation.