Dementia

Definition

Dementia is the name given to a group of neurological disorders that progressively deteriorate the ability of the brain to function normally. In order to be diagnosed with dementia, there must be:

• A disturbance in memory
• A decline in two or more cognitive domains that is sufficient in severity to cause functional impairment. These cognitive domains include language, visuospatial function, executive function (foresight, planning, anticipation, insight, etc.), and praxis (learned motor skills) .

Causes

Alzheimer's disease is the most common cause of dementia. Other causes of dementia include:

• Brain damage after multiple small strokes (so-called vascular dementia)
• Alcoholism
• AIDS
• Multiple sclerosis
• Huntington's disease
• Parkinson's disease
• Creutzfeldt-Jakob disease
• Lewy body dementia
• Pick's disease
• Normal pressure hydrocephalus
• Untreated syphilis
• Toxic levels of metals such as aluminum (as can sometimes occur in dialysis patients)
• Vitamin B12 deficiency
• Fronto-temporal dementia

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition.

Risk factors for dementia include:

• Advancing age
• Family members with dementing illness
• Down syndrome
• Apolipoprotein E status (a genetic risk)
• Elevated cholesterol
• Multiple strokes
• High blood pressure
• Vitamin deficiency
• Chronic drug use

Symptoms

Symptoms of dementia generally come on gradually. They often begin mildly and progress over time. Symptoms vary according to the cause of the dementia, but often include:

• Increasing trouble remembering things, such as:
  
  • How to get to familiar locations
  • The names of friends, family members
  • Where common objects are usually kept
  • Simple math
  • How to perform usual tasks, such as cooking, dressing, bathing, etc.
  • How to drive
  • Bill paying
• Trouble concentrating on tasks
• Trouble completing sentences, due to lost/forgotten words (This may progress to complete inability to speak.)
• Inability to remember the date, time of day, season
• Getting lost in familiar surroundings
• Mood swings
• Withdrawal, loss of interest in usual activities
• Personality changes
• Slow, shuffling walk
• Poor coordination
• Slowness and then loss of purposeful movement

Diagnosis

Doctors diagnose dementia by:

• Taking an extensive history from the patient and his or her family
• Closely observing the patient
• Performing a physical exam
• Performing mental status and psychological tests

There are no blood tests or imaging studies to definitively diagnose Alzheimer's disease, although certain types of brain imaging such as a SPECT or a PET scan can aid clinicians in making a diagnosis. Tests to rule out other causes of dementia and other medical conditions that may mimic dementia include:

• Blood tests for syphilis, vitamin B12, folate, thyroid, liver, and kidney function
• CT or MRI scans of the head—tests that use a computer (CT scan) or magnetic waves (MRI scan) to create detailed images of structures inside the body, in this case the head
• Lumbar puncture —collecting a sample of cerebrospinal fluid by inserting a needle between two vertebrae (rarely needed)
• Electroencephalogram (EEG) —a test that records the brain's activity by measuring electrical signals from the brain

Doctors must take care not to miss the diagnosis of depression , which can often present like dementia, particularly in the elderly. Unlike dementia, however, depression is highly treatable.

Treatment

Currently there are no treatments to cure Alzheimer’s disease or many other types of dementia. Researchers are studying various drugs to see if they can improve the symptoms of dementia or slow its course.

Prevention

There is no known way to prevent Alzheimer's disease. A healthful diet will prevent vitamin B12 deficiency and lower cholesterol. In addition to a healthy diet, exercise can also enhance cardiovascular health, which may delay the onset of vascular dementia.

Limiting alcohol intake can prevent dementia from alcoholism, and avoiding drug abuse and practicing safe sex reduces the risk of AIDS-related dementia. There is also some evidence that engaging in mentally stimulating activity over a lifetime may also reduce the risk of Alzheimer’s disease.