Alzheimer's disease (pronounced AHLZ-hi-merz) is a disorder that destroys cells in the brain. The disease is the leading cause of dementia, a condition that involves gradual memory loss, decline in the ability to perform routine tasks, disorientation, difficulty in learning, loss of language skills, impairment of judgment, and personality changes. As the disease progresses, people with Alzheimer's become unable to care for themselves. The loss of brain cells eventually leads to the failure of other systems in the body. The rate of progression of Alzheimer's varies from person to person. The time from the onset of symptoms until death ranges from 3 to 20 years. The average duration is about 8 years.
- What do we know about Alzheimer's?
- How is Alzheimer's disease diagnosed?
- What treatments are available?
- What additional help is available?
- What do we know about Alzheimer's?
Dr. Alois Alzheimer, a German physician, first described the disease in 1906. He observed in the autopsy of a woman with dementia two kinds of abnormal structures in the brain that are now recognized as hallmarks of Alzheimer's disease--amyloid plaques and neurofibrillary tangles. Since then, researchers have learned much about how these structures form, but they do not know exactly what role each structure plays in the loss of brain cells.
Studies have shown that the greatest known risk for developing Alzheimer's is increasing age. As many as 10 percent of people 65 years of age and older have Alzheimer's, and nearly 50 percent of people 85 and older have the disease. A family history of the disease is another known risk. Having a parent or sibling with the disease increases an individual's chances of developing Alzheimer's.
Scientists have identified three genes that cause rare, inherited forms of the disease that tend to occur before age 65. Investigations of these genes have provided important clues about the biology of Alzheimer's. Researchers have also identified one gene that raises the risk of the more common form of Alzheimer's that affects older people.
- How is Alzheimer's disease diagnosed?
Physicians can diagnose Alzheimer's disease with a level of accuracy exceeding 90 percent, but there is no single test to detect the disorder. A physician will use a variety of tests to assess memory and thinking skills and will usually ask a family member about changes in an individual's memory or behavior. The workup will also involve a thorough physical exam and a review of the individual's medical history. Various laboratory tests may be ordered, including blood or urine samples or brain imaging scans.
All of this information can help physicians identify the most probable cause of symptoms and rule out treatable conditions that may cause memory problems or other dementia symptoms. These include depression, adverse drug reactions, and nutritional deficiencies.
Researchers continue to investigate ways to improve diagnostic tools. New strategies may lead to earlier diagnosis and, therefore, earlier treatment.
- What treatments are available?
The U.S. Food and Drug Administration (FDA) has approved two classes of drugs to treat memory symptoms of Alzheimer's disease. The first specific Alzheimer medications to be approved were cholinesterase (KOH luh NES ter ace) inhibitors. Three of these drugs are commonly prescribed--donepezil (Aricept®), approved in 1996; rivastigmine (Exelon®), approved in 2000; and galantamine (Reminyl®), approved in 2001. Tacrine (Cognex®), the first cholinesterase inhibitor, was approved in 1993 but is rarely used today because of associated side effects, including possible liver damage.
All of these drugs work by temporarily increasing the brain's supply of acetylcholine (pronounced ah SEE til KOH lean), a cell-to-cell communication chemical involved in learning and memory that becomes deficient in the Alzheimer brain.
In October 2003, the FDA approved memantine (Namenda®), the first Alzheimer drug that works by regulating the activity of glutamate, another cell-to-cell communication chemical. Some glutamate is needed for learning and memory, but too much can overstimulate and damage nerve cells. Memantine protects brain cells against the effects of excess glutamate.
Physicians often prescribe vitamin E because it may block molecular activity contributing to brain cell damage. Other medications may be prescribed to treat such symptoms as agitation, anxiety, depression, and poor sleep.
Many care strategies and activities can be used to manage behavior, prevent agitation, and improve the quality of life for people with the disease. Such strategies may also lessen the stress that caregivers often experience.
Researchers are pursuing several lines of investigation for developing new treatments that may delay onset or slow progression of the disease. Many scientists believe that in the years to come we will have a regimen of drugs rather than a "magic bullet" for treating people with Alzheimer's disease and related disorders.
- What additional help is available?
The Alzheimer's Association, through its nationwide network of chapters, offers a broad range of programs and services for people with the disease, their families, and caregivers. Our 24-hour toll-free Contact Center at 800.272.3900 provides information, referral and care consultation with master's-level clinicians. For additional resources, please visit our Web site at www.alz.org or send an e-mail to info@alz.org.
