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About Alzheimer's
Click the links below to move to the appropriate section:
What is Alzheimer's?
Ten Warning Signs
How to get a Diagnosis
What Happens in the Brain of a Person with Alzheimer's Disease?
Early Onset Alzheimer's Disease
Late Stage Alzheimer's Disease
What Is Alzheimer's Disease?
Alzheimer's disease (pronounced AHLZ-hi-merz) is one of several disorders that cause the gradual loss of brain cells. The disease was first described in 1906 by German physician Dr. Alois Alzheimer. Although the disease was once considered rare, research has shown that it is the leading cause of dementia.
Dementia
Dementia is an umbrella term for several symptoms related to a decline in thinking skills. Common symptoms include a gradual loss of memory, problems with reasoning or judgment, disorientation, difficulty in learning, loss of language skills, and decline in the ability to perform routine tasks.
People with dementia also experience changes in their personalities and behavioral problems, such as agitation, anxiety, delusions (believing in a reality that does not exist), and hallucinations (seeing things that do not exist).
Disorders that cause dementia
Several disorders that are similar to Alzheimer's disease can cause dementia. These include front-temporal dementia, dementia with Lewy bodies, Parkinson's disease, Creutzfeldt-Jakob disease, and Huntington's disease. All of these disorders involve disease processes that destroy brain cells.
Vascular dementia is a disorder caused by the disruption of blood flow to the brain. This may be the result of a massive stroke or several tiny strokes.
Some treatable conditions such as depression, drug interactions, and thyroid problems can cause dementia. If treated early enough, these conditions may be effectively treated and even reversed.
Progression of Alzheimer's disease
Alzheimer's disease advances at widely different rates. The duration of the illness may vary from 3 to 20 years. The areas of the brain that control memory and thinking skills are affected first, but as the disease progresses, cells die in other regions of the brain. Eventually, the person with Alzheimer's will need complete care. If the individual has no other serious illness, the loss of brain function itself will cause death.
Causes and Risk Factors
No one knows yet exactly what causes Alzheimer's disease. Researchers are learning about what happens to the brain as we grow older, what happens to brain cells in Alzheimer's disease, what genes may be associated with Alzheimer's, and many other factors that may be important. Most researchers agree that the cause may be a complex set of factors.
Biology of Alzheimer's disease
There are two abnormal structures in the brain associated with Alzheimer's disease. Amyloid plaques (pronounced AM i loyd) are clumps of protein fragments that accumulate outside of cells. Neurofibrillary tangles (pronounced NUR o FI bri lair ee) are clumps of altered proteins inside cells.
Research about these structures have provided clues about why cells die, but scientists have not determined exactly what role plaques and tangles play in the disease process and whether these are the key factors.
Age and family history
Studies have shown that the greatest known risk for developing Alzheimer's is increasing age. As many as 10 percent of all people 65 years of age and older have Alzheimer's. Approximately 50 percent of all people 85 and older have the disease. A family history of Alzheimer's is another known risk. Having a parent or sibling with the disease increases an individual's chances of developing Alzheimer's.
Genetics
Scientists have identified three genes that cause rare, inherited forms of the disease that tend to occur before age 65. Researchers have also identified one gene that raises the risk of the more common form of Alzheimer's that affects older people.
Other factors
Much dementia research has focused on vascular risk factors, which are factors related to the blood circulation system. A great deal of evidence shows that disorders, such as high cholesterol and high blood pressure, factors that cause strokes and heart disease, may also increase the risk for developing Alzheimer's.
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Ten Warning Signs of Alzheimer's Disease
Some change in memory is normal as we grow older, but the symptoms of Alzheimer's disease are more than simple lapses in memory. People with Alzheimer's experience difficulties communicating, learning, thinking, and reasoning, problems severe enough to have an impact on an individual's work, social activities, and family life.
The Alzheimer's Association believes that it is critical for people with dementia and their families to receive information, care, and support as early as possible. To help family members and health care professionals recognize warning signs of Alzheimer's disease, the Association has developed a checklist of common symptoms.
1. Memory loss.
One of the most common early signs of dementia is forgetting recently learned information. While it's normal to forget appointments, names, or telephone numbers, those with dementia will forget such things more often and not remember them later.
2. Difficulty performing familiar tasks.
People with dementia often find it hard to complete every day tasks that are so familiar we usually do not think about how to do them. A person with Alzheimer's may not know the steps for preparing a meal, using a household appliance, or participating in a lifelong hobby.
3. Problems with language.
Everyone has trouble finding the right word sometimes, but a person with Alzheimer's disease often forgets simple words or substitutes unusual words, making his or her speech or writing hard to understand.
4. Disorientation to time and place.
It's normal to forget the day of the week or where you're going, but people with Alzheimer's disease can become lost on their own street, forget where they are and how they got there, and not know how to get back home.
5. Poor or decreased judgment.
No one has perfect judgment all of the time. Those with Alzheimer's may dress without regard to the weather, wearing several shirts or blouses on a warm day or very little clothing in cold weather. Individuals with dementia often show poor judgment about money, giving away large amounts of money to telemarketers or paying for home repairs or products they don't need.
6. Problems with abstract thinking.
Balancing a checkbook may be hard when the task is more complicated than usual. Someone with Alzheimer's disease could forget completely what the numbers are and what needs to be done with them.
7. Misplacing things.
Anyone can temporarily misplace a wallet or key. A person with Alzheimer's disease may put things in unusual places, an iron in the freezer or a wristwatch in the sugar bowl.
8. Changes in mood or behavior.
Everyone can become sad or moody from time to time. Someone with Alzheimer's disease can show rapid mood swings, from calm to tears to anger for no apparent reason.
9. Changes in personality.
People's personalities ordinarily change somewhat with age, but a person with Alzheimer's disease can change dramatically, becoming extremely confused, suspicious, fearful, or dependent on a family member.
10. Loss of initiative.
It's normal to tire of housework, business activities, or social obligations at times. The person with Alzheimer's disease may become very passive, sitting in front of the television for hours, sleeping more than usual, or not wanting to do usual activities.
If you recognize any warning signs in yourself or a loved one, the Alzheimer's Association recommends consulting a physician. Early diagnosis of Alzheimer's disease or other disorders causing dementia is an important step in getting appropriate treatment, care, and support services.
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How to Get a Diagnosis
Alzheimer’s disease can be diagnosed with 90 percent accuracy. The Alzheimer’s Association strongly encourages early diagnosis to enhance the benefits of treatment and allow the person to participate in planning and decision-making.
Early diagnosis is also important because it helps doctors to rule out other causes for the symptoms. Some conditions, such as depression, drug interaction, thyroid problems and certain vitamin deficiencies, may cause symptoms similar to Alzheimer’s disease and are usually reversible. If the doctor diagnoses Alzheimer’s disease, effective care and treatment options exist that can improve the quality of life for individuals with the disease and their care partners.
Family members usually notice symptoms first and should immediately report their observations to their doctor. An evaluation can then be conducted using a combination of tests. Following is an overview of how doctors may test a person for Alzheimer’s disease:
Medical History
The person being tested and family members will be inter-viewed, both individually and together, to gather background information on the person’s daily functioning, current mental and physical conditions and family medical history.
Mental Status Evaluation
During the mental status evaluation, the person’s sense of time and place, and ability to remember, understand, talk and do simple calculations will be assessed. The person may be asked the year, the day of the week or who the current president is. The person will also be asked to com-plete mental exercises, such as spelling a word backwards, writing a sentence or copying a design. When reviewing the test results, the physician will consider the individual’s overall performance in relation to his or her educational background and occupation.
Physical Examination
During the physical exam, the physician will evaluate the person’s nutritional status and check blood pressure and pulse. The physician will also search for the presence of cardiac, respiratory, liver, kidney and thyroid diseases, and arteriosclerosis (the hardening of the arteries). Some of these conditions can cause dementia-like symptoms and need to be ruled out before an accurate diagnosis of Alzheimer’s disease can be made.
Neurological Evaluation
A physician, often a neurologist, will closely evaluate the person’s nervous system for problems that may signal brain disorders other than Alzheimer’s disease. The physician will search for evidence of previous strokes, Parkinson’s disease, hydrocephalus (fluid accumulation in the brain), a brain tumor, and other illnesses that impair memory and/or thinking. The physician will examine the health of the brain by testing coordination, muscle tone and strength, eye movement, speech and sensation. For example, the physician will test reflexes by tapping the knee, check the person’s ability to sense feeling on their hands and feet, and listen for slurred speech.
Laboratory Tests
The physician will conduct a variety of laboratory tests to help diagnose Alzheimer’s disease by ruling out other disorders. A complete blood count and blood chemistry will be ordered to detect anemia, infection, diabetes and kidney and liver disorders. Levels of vitamin B12 and folic acid are measured, as low levels can be associated with dementia. Since very high or low amounts of the thyroid hormone can cause confusion or dementia, levels of the thyroid hormone are measured through a blood test.
The physician may also order an EEG (electroencephalogram) to detect abnormal brain wave activity. This test can detect conditions such as epilepsy, which can cause prolonged mild seizures that can leave a person in a confused state.
A CT (computed tomography) scan, which takes X-ray images of the brain, is also frequently used. The brain is scanned for evidence of tumors, strokes, blood clots and hydrocephalus. MRI (magnetic resonance imaging) is another brain-imaging technique sometimes used. More experimental tests may also be recommended but are not necessary for the diagnosis. These include PET (positron emission tomography), which shows how different areas of the brain respond when the person is asked to perform various activities, such as reading, listening to music, or talking; and SPECT (single proton emission computed tomography), which shows how blood is circulating to the brain.
Psychiatric, Psychological and Other Evaluations
A psychiatric evaluation can rule out the presence of other illnesses, such as depression, that can result in memory loss symptoms similar to Alzheimer’s. Neuropsychological testing may also be done to test memory, reasoning, writing, vision-motor coordination and ability to express ideas. These tests may take several hours, and may involve inter-views with a psychologist as well as written tests. These tests provide more in-depth information than the mental status evaluation.
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What Happens in the Brain of a Person with Alzheimer's?
Find out by visiting Inside the Brain: An Interactive Tour, an exciting new feature that explains how the brain works and how Alzheimer's disease affects it. Navigate at your own pace through 16 illustrated screens and follow the colored text highlights that serve as pathways to key areas and special features of each section.
Take the Inside the Brain tour at http://alz.org/brain/overview.asp
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For more detailed information on Alzheimer's Disease, visit the Alzheimer's Association website at www.alz.org.
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