Is there a connection among atrial fibrillation, anticoagulant treatment, and dementia?

It is well-known that atrial fibrillation carries an increased risk of stroke and dementia. The connecting pathogenic common mechanism is the thromboembolic state provided by atrial fibrillation, which is responsible for the acute cerebral events, as well as more saddle anatomic lesions, which accumulating over time, could lead to a progressive cognitive decline. It is plausible, instinctively, that oral anticoagulation could decrease this risk, although the possibility of micro-haemorrhages, which cannot be ignored, could make anticoagulation in this contest even dangerous. In this regard, whether there are firm, well established, evidences documenting a significant reduction in stroke occurrence with anticoagulant treatment in atrial fibrillation, the same level of evidences are not supporting the treatment in preventing dementia. Bringing some more clarity to this issue could have some considerable advantages, also in term of healthcare cost containment, considering the high prevalence of atrial fibrillation and dementia in the elderly.