Oral anticoagulants may reduce the risk of dementia in patients with atrial fibrillation (AF), according to a new study from Sweden. A retrospective registry study looked at 444,106 patients with AF. Patients on anticoagulant treatment at baseline demonstrated a 29% lower risk of dementia than patients without anticoagulation (hazard ratio, 0.71; 95% confidence interval, 0.68-0.74). For those who started anticoagulation earlier and stayed on anticoagulation longer, the benefit was nearly a 50% reduction in the incidence of dementia. There was no difference in risk reduction between vitamin K antagonists (warfarin) and non-vitamin K oral anticoagulants. There was more benefit in patients with higher CHA2DS2-VASc scores, suggesting that microembolization may be the cause of dementia in AF patients. The authors concluded that the risk of dementia is higher in AF patients without oral anticoagulation, suggesting that “early initiation of anticoagulation treatment in patients with AF could be of value in order to preserve cognitive function.” (Eur Heart J 2017 Oct 24. doi: 10.1093/eurheartj/ehx579)