Dementia and Other Related Illnesses

  • Dementia is the loss of mental functions like memory, judgment, language, and complex motor skills.
  • Alzheimer’s is the most common cause of dementia in the elderly, representing 60 percent of all dementias in those over 65.
  • Dementia can also be caused by several other disorders, including Parkinson’s disease, Huntingon’s disease, and Lewy body dementia.

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Dementia is a general term that describes the loss of memory, judgment, language, complex motor skills, and other intellectual function caused by damage to or death of the brain’s nerve cells. Each type of dementia is characterized by different structural changes in the brain (in Alzheimer’s, the accumulation of abnormal plaques and tangles).

Strokes, other blood-supply blockages, alcohol abuse, and head injuries can also lead to dementia. The symptoms and progression of dementia vary widely depending on its cause, the location and number of damaged brain cells, and other factors. Some dementias develop slowly over the course of years, while others may result in sudden changes.

Parkinson’s disease is a progressive disorder of the central nervous system that affects more than 1.5 million Americans. Parkinson’s causes both motor (movement-related) and non-motor symptoms, including dementia. Huntington’s disease is a degenerative brain disorder that slowly diminishes an individual’s ability to walk, talk, and think.

Named for abnormal brain-cell structures called Lewy bodies, Lewy body dementia (LBD) is the second-leading cause of degenerative dementia in the elderly. Although symptoms vary, hallucinations are usually present, along with other features of Alzheimer’s or Parkinson’s (the degree to which LBD is a distinct entity from those two diseases remains uncertain).

Next Step: Learn strategies to provide better care for someone with dementia.

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Experts at the Alzheimer’s Foundation of America have the answers to your toughest Alzheimer’s and dementia questions.

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