Alzheimer's Disease

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Alzheimer's disease facts

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  • Alzheimer's disease (AD) is a slowly progressive disease of the brain that is characterized by symptoms like impairment of memory and eventually by disturbances in reasoning, planning, language, and perception.
  • Alzheimer's disease is by far the most common cause for dementia in the United States and in most countries in the world.
  • The likelihood of having Alzheimer's disease increases substantially after the age of 70, and it may affect around 50% of persons over the age of 85.
  • The main risk factor for Alzheimer's disease is increased age. There are also genetic and other risk factors.
  • Characteristic symptoms and stages of Alzheimer disease include
    • problems with performing familiar tasks,
    • difficulty writing or speaking,
    • loss of orientation to time and place,
    • losing or misplacing items,
    • mood or behavior changes,
    • loss of interest in daily activities, and
    • poor judgment.
  • Symptoms may be present in varying degrees of severity.
  • There are numerous causes of dementia, so having the characteristic symptoms do not necessarily mean that a person has Alzheimer disease.
  • The diagnosis of Alzheimer's disease should be based on a comprehensive examination that rules out other causes of dementia.
  • Many other causes of dementia are screened for prior to diagnosing Alzheimer's disease.
  • The treatment and management of Alzheimer's disease consists of medications based and non-medication based treatments.

What is Alzheimer's disease?

Alzheimer's disease (AD) is a slowly progressive disease of the brain that is characterized by impairment of memory and eventually by disturbances in reasoning, planning, language, and perception. Many scientists believe that Alzheimer's disease results from an increase in the production or accumulation of a specific protein (beta-amyloid protein) in the brain that leads to nerve cell death.

The likelihood of having Alzheimer's disease increases substantially after the age of 70 and may affect around 50% of persons over the age of 85. Nonetheless, Alzheimer's disease is not a normal part of aging and is not something that inevitably happens in later life. For example, many people live to over 100 years of age and never develop Alzheimer's disease.

What's the difference between Alzheimer's disease and dementia?

Dementia is a syndrome characterized by:

  1. impairment in memory,
  2. impairment in another area of thinking such as the ability to organize thoughts and reason, the ability to use language, or the ability to see accurately the visual world (not because of eye disease), and
  3. these impairments are severe enough to cause a decline in the patient's usual level of functioning.

Although some kinds of memory loss are normal parts of aging, the changes due to aging are not severe enough to interfere with the level of function. Although many different diseases can cause dementia, Alzheimer's disease is the most common cause for dementia in the United States and in most countries in the world.

Medically Reviewed by a Doctor on 8/13/2015

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Alzheimer's Disease - Symptoms Question: Please describe the symptoms you or loved one experienced with Alzheimer's disease.
Alzheimer's Disease - Treatments Question: What stage of Alzheimer's disease are you or your loved one currently experiencing, and have any treatments been effective?
Alzheimer's Disease - Caregiver Question: What tips do you have for caregivers of someone with Alzheimer's disease?
Alzheimer's Disease - Dementia Question: Has a friend or relative been diagnosed with dementia? What are her/his symptoms?
Alzheimer's Disease - Warning Signs Question: Do you have any of the warning signs of Alzheimer's? Please discuss your symptoms and concerns.
Alzheimer's Disease - Home Safety Question: In what ways have you made the home safer for a friend or relative with Alzheimer's disease?
Alzheimer's Disease - Medications Question: If your relative is on a medication for Alzheimer's, what changes have you noticed?
Alzheimer's Disease - Driving Question: What motivated you to take away the keys or car from your loved one who has Alzheimer's?
Alzheimer's Disease - Experience Question: Do someone you love have Alzheimer's disease? Please share your experience.
Alzheimer's disease may be prevented or averted with brain exercises.

Early Signs and Symptoms of Alzheimer's Disease

The first stage of very early Alzheimer's disease often includes the following signs and symptoms:

  • Problems in thinking (trouble finding correct words, judgment errors)
  • Occasional disorientation
  • Mild memory loss
  • Difficulty with cognitive problems (problem solving)
  • Beginning difficulties moving the legs and feet