The effect of oral anticoagulants on the incidence of dementia in patients with atrial fibrillation: a systematic review and meta-analysis

Abstract Background Atrial fibrillation (AF) is a common cardiac arrhythmia, with dementia being an increasingly recognised complication of this. Treatment with oral anticoagulant (OAC) therapy may be protective in developing this complication. Purpose This meta-analysis aims to investigate the validity of this hypothesis, whilst additionally exploring the effect of specific OAC medication subtypes on the incidence of dementia. Methods A comprehensive search of MEDLINE and Embase for relevant studies reporting the efficacy of OAC therapy for the incidence of dementia in patients with AF was conducted from its inception until March 2023. This included observational studies that reported odds ratio, risk ratio and hazard ratio for adult AF patients. Studies including patients with prior OAC use or prior history of dementia were excluded. Statistical analysis was performed using a random-effects model to calculate the pooled hazard ratio and their corresponding 95% confidence interval for all outcomes. Subgroup analyses were also performed according to the study design, presence of observational window, and prior history of stroke in patients. Results A total of 13 studies were included in the study. Although the heterogeneity was high in all comparisons, we demonstrated that OAC usage lowered the risk of developing dementia in AF patients when compared to the non-OAC cohort. Looking more specifically at medication subtypes, direct oral anticoagulants (DOACs) and vitamin K agonists (VKA) were both effective in reducing the likelihood of AF patients developing dementia when compared to non-OAC treatments. Conclusion Our meta-analysis confirms that administration of OAC and its subtypes (VKA and DOAC) are effective pharmacotherapies in managing dementia in patients with AF. These findings have important clinical implications for the management of AF patients and highlight the need for further investigation of the protective effects of OAC therapy on cognitive decline. Future research should explore the long-term effects of OAC therapy on cognitive function in AF patients.