Depression and Alzheimer's disease.

In his classic case, Alzheimer described cognitive symptoms such as amnesia, aphasia, and apraxia and noncognitive symptoms such as delusions and agitation. Recent studies have suggested that depression also occurs in Alzheimer's disease. In this study, 144 patients who met criteria for Alzheimer's disease were examined for depression on a modified version of the Present State Examination. The prevalence rate of major depression was 17%. The depressed Alzheimer's disease patients were more cognitively impaired and more disabled than the nondepressed patients. Studies are needed to clarify the etiology and treatment of depression in Alzheimer's disease.