The mini strokes linked to vascular dementia are the result of hardening of the arteries. As this is not uncommon in the elderly, I suppose the comment refers to that fact. Not particularly helpful to you though. Unfortunately at present there doesn't seem to be any treatment for vascular dementia, other than to reduce the risk of further strokes by ensuring blood pressure is ok and is some cases prescribing an aspirin a day. The fact sheet on this website is helpful.
Blue sea