Definition

Dementia is a loss of mental ability severe enough to interfere with normal activities of daily living, lasting more than six months, not present since birth, and not associated with a loss or alteration of consciousness.

Description

Dementia is a group of symptoms caused by gradual death of brain cells. The loss of cognitive abilities that occurs with dementia leads to impairments in memory, reasoning, planning, and personality. While the over-whelming number of people with dementia are elderly, it is not an inevitable part of aging. Instead, dementia is caused by specific brain diseases. Alzheimer's disease is the most common cause, followed by vascular or multi-infarct dementia.

The prevalence of dementia has been difficult to...