What's the difference between Alzheimer's and other dementia?

Pathogenesis. Different dementias have different types of mechanisms that cause damage to the brain. Alzheimer's is a degenerative disease. Vascular dementia is due to small strokes. Vitamin deficiency is treatable cause if dementia, as are some other metabolic issue, e.g., thyroid disease. Other dementias have different pathologic processes.
Progress & cause. Dementia is brain failure & ad is the common cause followed by vascular , mixed etc with a small percentage of reversible like hypothyroid, pernicious anemia etc.In the real world , in my opinion differentian is primarily academia.
The cause or the. Pathology of the illness, meaning vascular dementias are caused by blood vessel problems rather than plaque formation, but lewy bodies are not plaques.