[Role of Alzheimer's type dementia among dementias of the elderly].

In the authors experience of a memory clinic, about 2/3 of the patients fulfilled the criteria for dementia and among the demented patients 2/3 had probable Alzheimer's disease. Vascular dementia is the second cause of dementia in elderly people, but two other degenerative disorders fulfilling the NINCDS-ADRDA criteria for Alzheimer disease (Mc Khann et al., 1984) account for degenerative dementia. There is now a consensus for the clinical diagnosis and the neuropathological aspects of these two diseases: Dementia with Lewy Bodies (Mc Keith et al., 1996) and fronto-temporal dementia (the Lund and Manchester groups, 1994). The authors emphasize the clinical aspects of those two diseases at an early stage in comparison with dementia of Alzheimer type.