May 4, 2009 -- Question: Could dementia be caused by something other than Alzheimer's disease?
Answer: Alzheimer's disease is the most common cause of dementia. It accounts for about two-thirds to three-fourths of all dementia. The remaining one-third to one-fourth is composed largely of Parkinson's disease and vascular dementia.
In Parkinson's disease, a neurologist can distinguish from Alzheimer's usually by changes in gait and motor function.
With vascular disease, there are usually multiple strokes, which account for the dementia destroying brain tissue.
There are also some rarer forms that account for the remaining fraction of all dementia.