Definition

Dementia is the name given to a group of disorders of the brain. They progressively damage 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 one or more cognitive domains that cause functional impairment in:
  • Language
  • Visuospatial function
  • Executive function (foresight, planning, anticipation, insight)
  • Praxis (learned motor skills)

Some Areas of the Brain Affected by Dementia

© 2009 Nucleus Medical Media, Inc.

Causes

Causes of dementia include:

• Alzheimer's disease —the most common cause of dementia
• 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 (fronto-temporal dementia)
• Normal pressure hydrocephalus
• Untreated syphilis
• Toxic levels of metals, such as aluminum (can sometimes occur in dialysis patients)
• Vitamin B12 deficiency
• Thiamine deficiency

Risk Factors

Risk factors for dementia include:

• Advancing age
• Family members with dementia
• Down syndrome
• Apolipoprotein E status (a genetic risk)
• Elevated cholesterol
• Multiple strokes
• High blood pressure
• Diabetes
• High cholesterol
• Obesity
• Lack of physical activity
• Vitamin deficiency
• Chronic drug use
• Long-term use of hormone replacement therapy
• Repetitive head trauma (eg, may occur with contact sports)
• Overweight or obese

Symptoms

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
  • What the names of family and friends are
  • Where common objects are usually kept
  • How to do simple math
  • How to do usual tasks, such as cooking, dressing, bathing, etc.
  • How to drive
  • How to pay bills
• Having difficulty concentrating on tasks
• Having difficulty completing sentences due to lost/forgotten words (may progress to complete inability to speak)
• Forgetting the date, time of day, season
• Getting lost in familiar surroundings
• Having mood swings
• Being withdrawn, losing interest in usual activities
• Having personality changes
• Walking in a slow, shuffling way
• Having poor coordination
• Losing purposeful movement

Diagnosis

Doctors diagnose dementia by:

• Getting an extensive medical history from you and your family
• Closely observing you
• Doing a physical and neurological exam
• Doing mental status and psychological tests

There are no blood tests or exams that can definitively diagnose Alzheimer's disease. Certain types of brain imaging such as a SPECT or a PET scan may aid in 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 scan —a type of x-ray that uses a computer to make pictures of structures inside the head
• MRI scan —a test that uses magnetic waves to make pictures of structures inside the head
• PET or SPECT scans—tests that use dyes to measure the activity levels of various areas of the brain (used in some cases)
• Lumbar puncture —a test of the cerebrospinal fluid (CSF) from the lower back; may be done to look for infection or bleeding
• Electroencephalogram (EEG) —a test that records the brain's activity by measuring electrical signals from the brain

The doctor will also check to see if you have depression . It can often present like dementia.

Treatment

Currently, there are no treatments to cure many types of dementia. Various drugs are being studied to see if they can decrease the symptoms of dementia or slow its course.

Prevention

There is no known way to prevent dementia. In general:

• Eat a healthy diet . This will help you to maintain good levels of vitamin B12 and cholesterol.
• Exercise regularly . This can also enhance cardiovascular health, which may delay the onset of vascular dementia.
• Drink alcohol only in moderation. This means no more than two drinks per day for a man, and one drink per day for a woman. Moderate amounts of alcohol may decrease your risk of dementia. But higher amounts of alcohol can increase your risk of dementia.
• Avoid drug abuse . Also, practice safe sex. This can reduce the risk of AIDS -related dementia.
• Engage in mentally stimulating activity. This may also reduce the risk of Alzheimer’s disease .