Definition  

Alzheimer's disease is a progressive condition that destroys brain cells. It is the most common cause of dementia . People with this disease slowly lose the ability to learn, function, and remember.

Areas of the Brain Affected by Alzheimer's Disease  

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Causes  

The cause is not yet known. Studies suggest that two main mechanisms are involved with the development of Alzheimer's disease:

  • Plaques—abnormal deposits of a substance called beta amyloid in different areas of the brain
  • Neurofibrillary tangles—twisted fibers within nerve cells
Risk Factors  

Factors that increase your chance of Alzheimer's disease include:

  • Age: 65 and older
  • Previous serious, traumatic brain injury
  • Lower educational achievement
  • Down's syndrome
  • Down's syndrome in a first-degree relative
  • Women under 35 who give birth to a child with Down's syndrome
  • Smoking
  • Family history of Alzheimer's disease
  • Presence of a certain variety type of apolipoprotein (APOE-e4)
  • Depression
  • Elevated levels of homocysteine
  • Heart disease

Researchers are studying the following to see if they are related to Alzheimer's disease:

  • Poor nutrition and vitamin deficiency in childhood
  • Exposure to electromagnetic fields
  • Excess metal in the blood, especially zinc, copper, aluminum, and iron
  • Certain viral infections
  • Diabetes
  • High Cholesterol
Symptoms  

The disease begins as mild memory lapses. It moves to profound loss of memory and function. Alzheimer's disease is divided into three stages:

  • Early—memory and cognition loss are noticeable but still able to function independently
  • Intermediate—mental loss, personality changes more dependent on others for basic needs
  • Severe—loss of personality and bodily functions; total dependence for care

Symptoms include:

  • Increasing trouble remembering things, such as
    • How to get to familiar places
    • Names of friends and family members
    • Where common objects are kept
    • Simple math
    • How to perform tasks (eg, cooking, dressing, bathing)
  • Trouble concentrating on tasks
  • Trouble completing sentences due to lost or forgotten words (progresses to a complete inability to speak)
  • Difficulty with daily life tasks such as bill paying and housekeeping
  • Inability to remember the date, time of day, season
  • Mood swings
  • Withdrawal, loss of interest in usual activities
  • Slow, shuffling walk
  • Poor coordination
  • Slowness and then loss of purposeful movement
Diagnosis  

There are no tests to definitively diagnose this disease. The doctor will ask about your symptoms and medical history. A physical exam will be done. The doctor will ask many questions. This will help to rule out other causes.

Tests to rule out other medical conditions may include:

  • Neurological exam
  • Psychological and mental status testing
  • CT scan —a type of x-ray that uses a computer to make pictures of the brain
  • MRI scan —a test that uses magnetic waves to make pictures of the brain
  • Electroencephalogram (EEG) —a test that measures electrical currents in the brain
  • Blood tests and urine tests
  • Lumbar puncture —to test for levels of certain brain proteins that increase with Alzheimer’s disease and to rule out other disorders
Treatment  

There is no cure for Alzheimer's disease. There are also no certain ways to slow its progression. Four medications have received approval for the treatment of some symptoms. Various drugs are being studied to see if they can manage the symptoms or slow its course.

Medications for Symptoms and Disease Progression  

Medications being used and studied include:

  • Cholinesterase inhibitors (eg, donepezil , rivastigmine , galantamine )
  • NMDA receptor antagonist (eg, memantine )
  • Antioxidants (eg, vitamin E)
  • Estrogen
  • Anti-inflammatory agents
  • Ginkgo biloba (herbal supplement)
Lifestyle Management  

Managing the disease includes:

  • Creating an environment in which you can receive the care you need
  • Optimizing your quality of life
  • Keeping yourself safe
  • Helping yourself learn to deal with the frustration of your uncontrollable behavior
  • Providing a calm, quiet, predictable environment
  • Providing appropriate eyewear and hearing aids, easy-to-read clocks and calendars
  • Playing quiet music
  • Light, appropriate exercise to reduce agitation and relieve depression
  • Encouraging family and close friends to visit frequently
Psychiatric Medications  

Medications to treat the psychiatric symptoms that may occur with Alzheimer’s disease include:

  • Antidepressants—to treat depression
  • Anxiolytics—to treat anxiety
  • Antipsychotics—to treat severe confusion, paranoia, and hallucinations
Caregiver Support  

Caring for a person with Alzheimer's disease is extremely difficult and exhausting. The primary caregiver needs emotional support, as well as regular respite.

If you are diagnosed with Alzheimer's disease, follow your doctor's instructions .

Prevention  

There are no guidelines for preventing Alzheimer's disease because the cause is unknown.