Dementia is not the name of a disease, it’s really just a description of a set of symptoms. It describes people who have enough cognitive impairment to the point where they can no longer function independently. It’s become somewhat synonymous with Alzheimer’s disease. But Alzheimer’s disease itself is a specific disease that is only one cause of dementia. There are other degenerative diseases that cause dementia, for example, dementia with Lewy bodies, frontotemporal lobar degeneration, vascular problems, and so on.