Definition
Dementia is a loss of brain function. It is not a single disease. Instead, dementia refers to a group of illnesses that involve memory, behavior, learning, and communicating problems. The problems are progressive, which means they slowly get worse.
Alternative Names
Chronic brain syndrome; Lewy body dementia; DLB; Vascular dementia
Causes, incidence, and risk factors
The two major causes of degenerative (non-reversible) dementia are Alzheimer's disease and vascular dementia (loss of brain function due to a series of small strokes). The two conditions often occur together.
Dementia with Lewy bodies (DLB) is a leading cause of degenerative dementia in elderly adults. This condition is linked to abnormal protein structures in certain areas of the brain. The structures and symptoms of DLB are associated with Alzheimer's disease, but it is uncertain whether DLB is a sub-type of Alzheimer's or separate disease. There is no cure for DLB or Alzheimer's.
Conditions that damage blood vessels or nerve structures of the brain can also lead to dementia.
Treatable causes of dementia include normal pressure hydrocephalus, brain tumors, and dementia due to metabolic causes, thyroid conditions, low vitamin B12 levels, and infections.
Dementia may be diagnosed when a patient has two or more problems in brain function. Problems may involve language, memory, perception, emotional behavior or personality, and cognitive skills (such as calculation, abstract thinking, or judgment). Dementia usually first appears as forgetfulness. Other symptoms may only be seen during a medical exam or with cognitive tests.
Dementia usually occurs in older age. Dementia is rare in people under age 60. The risk for dementia increases as a person gets older.
Symptoms
- Progressive memory loss
- Inability to concentrate
- Decrease in problem-solving skills and judgment capability
- Confusion, severe
- Hallucinations and delusions
- Altered sensation or perception
- Impaired recognition (agnosia)
- Impaired recognition of familiar objects or persons
- Impaired recognition through the senses
- Altered sleep patterns
- Insomnia
- Need for increased sleep
- Disturbance or change in sleep-wake cycle
- Motor system impairment
- Impaired skilled motor function (apraxia)
- Inability to reproduce geometric figures
- Inability to mimic hand positions
- Inability to dress self
- Gait changes
- Inappropriate movements
- Other motor system impairment
- Disorientation
- Person, place, time disorientation
- Visual-spatial disorientation
- Inability to interpret environmental cues
- Specific disorders of problem-solving or learning
- Inability to generalize
- Loss of abstract thinking
- Impaired calculating ability
- Inability to learn
- Memory deficit
- Short-term memory problems (can't remember new things)
- Long-term memory problems (can't remember past)
- Absent or impaired language ability (aphasia)
- Inability to comprehend speech
- Inability to read
- Inability to write
- Inability to speak, without muscle paralysis
- Inability to form words
- Inability to name objects
- Poor enunciation
- Inappropriate speech; use of jargon or wrong words
- Inability to repeat a phrase
- Persistent repetition of phrases
- Other language impairment
- Personality changes
- Irritability
- Poor temper control
- Anxiety
- Depression
- Indecisiveness
- Self-centeredness
- Inflexibility
- No observable mood (flat affect)
- Inappropriate mood or behavior
- Withdrawal from social interaction
- Inability to function or interact in social or personal situations
- Inability to maintain employment
- Decreased ability to care for oneself
- Decreased interest in daily living activities
- Lack of spontaneity
Additional symptoms that may be associated with this disease are as follows:
Signs and tests
The following tests and procedures may be done to determine the severity of dementia and its cause:
Print
