Dementia at old age: a clinical end-point of atherosclerotic disease.

The main causes of dementia at old age are Alzheimer's disease and vascular dementia. The clinical presentations of late-onset Alzheimer's disease and vascular dementia can barely be differentiated. This clinical observation is supported by pathological findings. Late-onset dementia should be considered a multifactorial disease, in which both vascular factors and amyloid dispositions contribute to cognitive decline.