Dementia Definition

What is Dementia?

Dementia, also called senility, is not a specific disease.^[1] It is a group of symptoms related to brain function. In dementia, brain function is impaired enough to disrupt daily activities such as dressing or driving.^[2] To be considered dementia, at least two brain functions must be impaired. Typically, it affects memory, judgment or language. Two of these functions must be impaired for the condition to be considered dementia. In addition, there may be changes in personality and social behavior. Some forms of dementia can be stopped or reversed with treatment.^[3]

Dementia can occur as a part of another disorder. Typically, these other disorders are ones involving movement such as Parkinson's disease. When dementia occurs as a part of another disorder, it is called secondary dementia.

The number of people with dementia has increased over the last few decades.^[4] This may be due to increased awareness or a larger number of elderly people. About 2 million people in the United States have dementia. From 5% to 8% of people over age 65 have dementia and the number who have dementia doubles for every 5 years of age over 65.