Metasynthesis of the neurobiology of Alzheimer’s disease

Alzheimer’s disease (AD) is by far the most common cause of dementia. It appears to have several causes, some of which are very rare. These are discussed later in the chapter. AD accounts for about one-third of all dementia cases in the elderly. Another third is of vascular origin (resulting primarily from the accumulation of strokes or infarcts), and the last third are mostly mixed cases of both AD and vascular dementia. Dementia, and in particular AD, occurs primarily in elderly persons (Arendt 2001; Terry et al. 1999).