Non-Vitamin K Antagonist Oral Anticoagulants in Secondary Stroke Prevention in Atrial Fibrillation Patients: An Updated Analysis by Adding Observational Studies

Background This meta-analysis aimed to evaluate the efficacy and safety of non-vitamin K antagonist oral anticoagulants (NOACs) versus vitamin K antagonists (VKAs) in secondary stroke prevention in atrial fibrillation (AF) patients. Methods PubMed and Embase electronic databases were systematically searched from January 2009 to July 2019 for relevant randomized clinical trials and observational studies. A random-effects model was applied in the pooled analysis. Results A total of 14 studies (4 randomized clinical trials and 10 observational studies) were included. Based on the randomized clinical trials, compared with VKA use, the use of NOACs was associated with decreased risk of stroke and systemic embolism, major bleeding, and intracranial bleeding. Based on the observational studies, compared with VKAs, the subgroup analysis showed that dabigatran and rivaroxaban were associated with a reduced risk of stroke or systemic embolism, whereas dabigatran and apixaban were associated with a decreased risk of major bleeding. Conclusion Based on current data, the use of NOACs is at least non-inferior to the use of VKAs in AF patients for secondary stroke prevention irrespective of NOAC type.