Dementia in the elderly: the silent epidemic.

The graying of America will be accompanied by an epidemic of major proportions--dementia or intellectual impairment--that will have an impact on all aspects of the helath care system, particularly on the institutional component of the long-term care system. Health professionals; federal, state, and local health planners; families; and others must recognize that many ameliorable or curable physical and emotional diseases in the elderly are associated with intellectual impairment that may be difficult to distinguish from irreversible brain disease of the Alzheimer type. We present information on the cause, physiopathologic mechanism, clinical presentation, appropriate laboratory studies, and anticipated outcomes in the various forms of intellectual impairment found in the elderly. Important new developments will occur in the next decade that will address the cause, pathogenesis, further refinement of laboratory investigation, and specific therapeutic intervention in dementia.