Alzheimer's disease causes brain changes that gradually get worse. It's the most common cause of dementia — a group of brain disorders that cause progressive loss of intellectual and social skills, severe enough to interfere with day-to-day life. In Alzheimer's disease, brain cells degenerate and die, causing a steady decline in memory and mental function.
Current Alzheimer's disease medications and management strategies can temporarily improve symptoms, maximize function and maintain independence. It's also important to seek social services and tap into your support network to make life better. Research efforts aim to discover treatments that prevent Alzheimer's or slow its progression.
The first symptoms of Alzheimer's disease you may notice are increasing forgetfulness and mild confusion. Over time, the disease has a growing impact on your memory, your ability to speak and write coherently, and your judgment and problem solving. If you have Alzheimer's, you may be the first to notice that you're having unusual difficulty remembering things and organizing your thoughts. Or you may not recognize that anything is wrong, even when changes are noticeable to your family members, close friends or co-workers.
Brain changes associated with Alzheimer's disease lead to growing trouble with:
Disorientation and misinterpreting spatial relationships
Speaking and writing
Thinking and reasoning
Making judgments and decisions
Planning and performing familiar tasks
Changes in personality and behavior
Scientists believe that for most people, Alzheimer's disease results from a combination of genetic, lifestyle and environmental factors that affect the brain over time.
Less than 5 percent of the time, Alzheimer's is caused by specific genetic changes that guarantee a person will develop the disease.
While the causes of Alzheimer's are not yet fully understood, its effect on the brain is clear. Alzheimer's disease damages and kills brain cells. A brain affected by Alzheimer's disease has many fewer cells and many fewer connections among surviving cells than does a healthy brain.
As more and more brain cells die, Alzheimer's leads to significant brain shrinkage. When doctors examine Alzheimer's brain tissue under the microscope, they see two types of abnormalities that are considered hallmarks of the disease:
People with rare genetic changes that guarantee they'll develop Alzheimer's often begin experiencing symptoms in their 40s or 50s.
Family history and genetics
Mild cognitive impairment
Lifestyle and heart health
However, some evidence suggests that the same factors that put you at risk of heart disease may also increase the chance that you'll develop Alzheimer's. Examples include:
These risk factors are also linked to vascular dementia, a type of cognitive decline caused by damaged blood vessels in the brain. Many people with cognitive decline have brain changes characteristic of both Alzheimer's disease and vascular dementia. Some researchers think that each condition helps fuel the damage caused by the other.
Working with your health care team on a plan to control these factors will help protect your heart — and may also help reduce your risk of dementia.
Lifelong learning and social engagement
Factors that may reduce your risk of Alzheimer's include:
Scientists can't yet explain this link. One theory is that using your brain develops more cell-to-cell connections, which protects your brain against the impact of Alzheimer-related changes. Another theory is that it may be harder to measure cognitive decline in people who exercise their minds frequently or who have more education. Still another explanation is that people with Alzheimer's disease may be less inclined to seek out stimulating activities years before their disease can be diagnosed.
Memory loss, impaired judgment and other cognitive changes caused by Alzheimer's can complicate treatment for other health conditions. A person with Alzheimer's disease may not be able to:
As Alzheimer's disease progresses, brain changes begin to affect physical functions such as swallowing, balance, and bowel and bladder control. These effects can increase vulnerability to additional health problems such as:
Preparing for your appointment
You may decide you want to talk to your doctor about memory loss or other cognitive changes, or you may seek care at the urging of a family member who arranges your appointment and goes with you. You'll probably start by seeing your family doctor or general practitioner, who may refer you to a neurologist, psychiatrist or neuropsychologist for further evaluation.
Because appointments can be brief and there's often a lot of ground to cover, it's a good idea to prepare ahead of time. Here are some suggestions to help you get ready for your appointment and understand what to expect from your doctor.
What you can do
Questions to ask your doctor
In addition to the questions you've prepared ahead of time, don't hesitate to ask your doctor to clarify anything you don't understand.
What to expect from your doctor
Tests and diagnosis
There's no specific test today that confirms you have Alzheimer's disease. Your doctor will make a judgment about whether Alzheimer's is the most likely cause of your symptoms based on the information you provide and results of various tests that can help clarify the diagnosis.
Doctors can nearly always determine whether you have dementia, and they can accurately identify whether your dementia is due to Alzheimer's disease about 90 percent of the time. Alzheimer's disease can be diagnosed with complete accuracy only after death, when microscopic examination of the brain reveals the characteristic plaques and tangles.
To help distinguish Alzheimer's disease from other causes of memory loss, doctors now typically rely on the following types of tests.
Physical and neurological exam
Mental status testing
Brain-imaging technologies include:
Future diagnostic tools
Treatments and drugs
Creating a safe and supportive environment
People with Alzheimer's who develop trouble walking may still be able to use a stationary bike or enjoy chair exercises. You may be able to find exercise programs geared to older adults on TV or on DVDs.
Certain nutritional supplements are marketed as "medical foods" specifically to treat Alzheimer's disease. The Food and Drug Administration (FDA) does not approve products marketed as medical foods. Despite marketing claims, there's no definitive data showing that any of these supplements is beneficial or safe.
Lifestyle and home remedies
Study results have been mixed about whether diet, exercise or other healthy lifestyle choices can prevent or reverse cognitive decline. But these healthy choices promote good overall health and may play a role in maintaining cognitive health, so there's no harm in including these strategies in your general wellness plan:
Various herbal mixtures, vitamins and other supplements are widely promoted as preparations that may support cognitive health or prevent or delay Alzheimer's. The National Institutes of Health (NIH) convened an expert panel that concluded current evidence doesn't support any benefit from taking vitamin B, vitamin C, vitamin E, folic acid or beta carotene.
Omega-3 fatty acids
Supplements promoted for cognitive health can interact with medications you're taking for Alzheimer's disease or other health conditions. Work closely with your health care team to create a treatment plan that's right for you. Make sure you understand the risks and benefits of everything it includes.
Coping and support
People with Alzheimer's disease experience a mixture of emotions — confusion, frustration, anger, fear, uncertainty, grief and depression.
You can help a person cope with the disease by being there to listen, reassuring the person that life can still be enjoyed, providing support, and doing your best to help the person retain dignity and self-respect.
A calm and stable home environment can help reduce behavior problems. New situations, noise, large groups of people, being rushed or pressed to remember, or being asked to do complicated tasks can cause anxiety. As a person with Alzheimer's becomes upset, the ability to think clearly declines even more.
Caring for the caregiver
Many people with Alzheimer's and their families benefit from counseling or local support services. Contact your local Alzheimer's Association affiliate to connect with support groups, doctors, resources and referrals, home care agencies, residential care facilities, a telephone help line, and educational seminars.
Right now, there's no proven way to prevent Alzheimer's disease. Research into prevention strategies is ongoing. The strongest evidence so far suggests that you may be able to lower your risk of Alzheimer's disease by reducing your risk of heart disease. Many of the same factors that increase your risk of heart disease can also increase your risk of Alzheimer's disease and vascular dementia. Important factors that may be involved include high blood pressure, high cholesterol, excess weight and diabetes.
Keeping active — physically, mentally and socially — may make your life more enjoyable and may also help reduce the risk of Alzheimer's disease.
Last Updated: 2011-01-18
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