Most types of dementia are nonreversible (degenerative). Nonreversible means the changes in the brain that are causing the dementia cannot be stopped or turned back. Alzheimer's disease is the most common type of dementia.
Lewy body disease is a leading cause of dementia in elderly adults. People with this condition have abnormal protein structures in certain areas of the brain.
Dementia also can be due to many small strokes. This is called vascular dementia.
The following medical conditions also can lead to dementia:
Use of certain medications, including cimetidine and some cholesterol-lowering medications
Dementia usually occurs in older age. It is rare in people under age 60. The risk for dementia increases as a person gets older.
Dementia symptoms include difficulty with many areas of mental function, including:
Emotional behavior or personality
Cognitive skills (such as calculation, abstract thinking, or judgment)
Dementia usually first appears as forgetfulness.
Mild cognitive impairment is the stage between normal forgetfulness due to aging and the development of dementia. People with MCI have mild problems with thinking and memory that do not interfere with everyday activities. They are often aware of the forgetfulness. Not everyone with MCI develops dementia.
Symptoms of MCI include:
Difficulty performing more than one task at a time
Difficulty solving problems or making decisions
Forgetting recent events or conversations
Taking longer to perform more difficult mental activities
The early symptoms of dementia can include:
Difficulty performing tasks that take some thought, but that used to come easily, such as balancing a checkbook, playing games (such as bridge), and learning new information or routines
Getting lost on familiar routes
Language problems, such as trouble finding the name of familiar objects
Losing interest in things you previously enjoyed, flat mood
Personality changes and loss of social skills, which can lead to inappropriate behaviors
As the dementia becomes worse, symptoms are more obvious and interfere with the ability to take care of yourself. The symptoms may include:
Change in sleep patterns, often waking up at night
Difficulty doing basic tasks, such as preparing meals, choosing proper clothing, or driving
Forgetting details about current events
Forgetting events in your own life history, losing awareness of who you are
The condition of a person with dementia gets worse
You are unable to care for a person with dementia at home
Most causes of dementia are not preventable.
Quitting smoking and controlling high blood pressure and diabetes can help you reduce your risk of vascular dementia. This is dementia caused by a series of small strokes. Eating a low-fat diet and exercising regularly may also reduce the risk of vascular dementia.
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Luc Jasmin, MD, PhD, Department of Neurosurgery at Cedars-Sinai Medical Center, Los Angeles, and Department of Anatomy at UCSF, San Francisco, CA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.