What is the difference?
Dementia happens usually to the elderly. It is a gradual process of mind deterioration. Alzheimer’s is a disease of the brain that also affects autonomic brain function. It can start much earlier, it’s course can be much faster and it can affect things such as swallowing and breathing.
It’s not that someone just stops eating, they literally forget how to eat.
Finally the “wiring” of things like breathing shut down.
In Dementia, it is physically different. It doesn’t impact the physical nerve functions.
In essence, the test of Alzheimer’s is the elimination of everything else.