Dementia: Not always Alzheimer's
Dementia: Not always Alzheimer's
Dementia occurs in Alzheimer's — but Alzheimer's is not the only possible cause.
Dementia is a neurological disorder that affects your ability to think, speak, reason, remember and move. While Alzheimer's disease is the most common cause of dementia, many other conditions also cause these symptoms. Some of these disorders get worse with time and cannot be cured. Other types can be treated and reversed.
The three most common forms of dementia are Alzheimer's disease, vascular dementia and Lewy body dementia. Sometimes, a person can have more than one of these problems at the same time.
Alzheimer's disease: Most common cause
Alzheimer's disease involves a loss of nerve cells in the areas of the brain vital to memory and other mental functions. This loss is associated with the development of abnormal clumps and tangles of protein in brain cells.
The first sign of Alzheimer's disease is usually forgetfulness. As the disease progresses, it affects language, reasoning and understanding. Eventually, people with Alzheimer's lose the ability to care for themselves.
The precise cause of Alzheimer's disease is unknown, but risk increases with age. Ten percent of the population over the age of 65 has Alzheimer's, while nearly half of the population over 85 has the disease.
Vascular dementia: Frequently follows stroke
Another common form of dementia, vascular dementia occurs when arteries feeding the brain become narrowed or blocked. The onset of symptoms usually is abrupt, frequently occurring after a stroke.
However, some forms of vascular dementia progress slowly, making them difficult to distinguish from Alzheimer's disease. Some people have Alzheimer's and vascular dementia at the same time.
Vascular dementia often causes problems with thinking, language, walking, bladder control and vision. Preventing additional strokes by treating underlying diseases, such as high blood pressure, may halt the progression of vascular dementia.
Lewy body dementia: Has Alzheimer's-like and Parkinson's-like features
In this form of dementia, abnormal round structures — Lewy bodies — develop within cells of the midbrain, beneath the cerebral hemispheres. Lewy body dementia shares characteristics with both Alzheimer's disease and Parkinson's disease. Like Alzheimer's disease, it causes confusion and impaired memory and judgment. And it often produces two distinctive physical signs typical of Parkinson's disease — a shuffling gait and flexed posture. Lewy body dementia can also cause hallucinations.
Lewy bodies contain a protein associated with Parkinson's disease, and Lewy bodies often are found in the brains of people who have Parkinson's disease or Alzheimer's disease. This suggests that the three ailments are related, or that Lewy body dementia and Alzheimer's or Parkinson's disease sometimes co-exist in the same person. Some people with Lewy body dementia have experienced dramatic improvements in symptoms when treated with Alzheimer's or Parkinson's medications.
Other disorders linked to dementia
Several less common brain disorders also can result in dementia.
Some causes are treatable
Many other conditions, some reversible, can cause dementia or dementia-like symptoms.
Seek evaluation and treatment
Dementia isn't always due to Alzheimer's. Before you conclude that a loved one's memory loss and confusion stem from an irreversible disease process, get a thorough medical evaluation. Even if the evaluation uncovers no underlying condition that, with treatment, can reverse dementia, options may be available for easing its symptoms. Knowing the likely cause of dementia, however, is the essential first step toward managing it.
Last Updated: 04/21/2006
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