Dementia is a loss of brain function that occurs with certain diseases. It affects memory, thinking, language, judgment, and behavior.
Chronic brain syndrome; Lewy body dementia; DLB; Vascular dementia; Mild cognitive impairment; MCI
Dementia usually occurs in older age. Most types are rare in people under age 60. The risk of dementia increases as a person gets older.
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 disease is the most common type of dementia.
Another common type of dementia is vascular dementia. It is caused by poor blood flow to the brain, such as with stroke.
Lewy body disease is a common cause of dementia in older adults. People with this condition have abnormal protein structures in certain areas of the brain.
The following medical conditions can also lead to dementia:
Some causes of dementia may be stopped or reversed if they are found soon enough, including:
Dementia symptoms include difficulty with many areas of mental function, including:
Dementia usually first appears as forgetfulness.
Mild cognitive impairment (MCI) 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 daily activities. They often know about their forgetfulness. Not everyone with MCI develops dementia.
Symptoms of MCI include:
Early symptoms of dementia can include:
As dementia becomes worse, symptoms are more obvious and interfere with the ability to take care of oneself. Symptoms may include:
People with severe dementia can no longer:
Other symptoms that may occur with dementia:
Treatment depends on the condition causing the dementia. Some people may need to stay in the hospital for a short time.
Sometimes, dementia medicine can make a person's confusion worse. Stopping or changing these medicines is part of the treatment.
Certain mental exercises can help with dementia.
Treating conditions that can lead to confusion often greatly improve mental function. Such conditions include:
Medicines may be used to:
Someone with dementia will need support in the home as the disease gets worse. Family members or other caregivers can assist by helping the person cope with memory loss and behavior and sleep problems. It is important to make sure the homes of people who have dementia are safe for them.
People with MCI do not always develop dementia. When dementia does occur, it usually gets worse over time. Dementia often decreases quality of life and lifespan. Families will likely need to plan for their loved one's future care.
Call your provider if:
Most causes of dementia are not preventable.
The risk of vascular dementia may be reduced by preventing strokes through:
Knopman DS. Cognitive impairment and other dementias. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 374.
Peterson R, Graff-Radford J. Alzheimer disease and other dementias. In: Daroff RB, Jankovic J, Mazziotta JC, Pomeroy SL, eds. Bradley's Neurology in Clinical Practice. 7th ed. Philadelphia, PA: Elsevier; 2016:chap 95.
Petersen RC, Lopez O, Armstrong MJ, et al. Practice guideline update summary: mild cognitive impairment: report of the Guideline Development, Dissemination, and Implementation Subcommittee of the American Academy of Neurology. Neurology. 2018;90(3):126-135.PMID: 29282327 pubmed.ncbi.nlm.nih.gov/29282327.