An early, accurate diagnosis of Alzheimer's disease (AD) helps patients and their families plan for the future. It gives them time to discuss care while the patient can still take part in making decisions. Early diagnosis will also offer the best chance to treat the symptoms of the disease.
Today, the only definite way to diagnose Alzheimer's disease is to find out whether there are plaques and tangles in brain tissue. To look at brain tissue, however, doctors usually must wait until they do an autopsy, which is an examination of the body done after a person dies. Therefore, doctors can only make a diagnosis of "possible" or "probable" AD while the person is still alive.
At specialized centers, doctors can diagnose Alzheimer's Disease correctly up to 90 percent of the time. Doctors use several tools to diagnose "probable" Alzheimer's Disease, including:
- Questions about the person's general health, past medical problems, and ability to carry out daily activities
- Tests of memory, problem solving, attention, counting, and language
- Medical tests—such as tests of blood, urine, or spinal fluid, and brain scans
Sometimes these test results help the doctor find other possible causes of the person's symptoms. For example, thyroid problems, drug reactions, depression, brain tumors, and blood vessel disease in the brain can cause AD-like symptoms. Some of these other conditions can be treated successfully.
Treatments for Alzheimer's Disease
No treatment has been proven to stop Alzheimer's disease. However, for some people in the early and middle stages of the disease, the drugs tacrine, donepezil, rivastigmine, or galantamine, may help prevent some symptoms from becoming worse for a limited time in some patients. (Tacrine is no longer actively marketed by the manufacturer.) Another drug, memantine, has been approved to treat moderate to severe AD, although it also is limited in its effects. And the FDA recently approved the use of donepezil to treat moderate to severe AD.
Also, some medicines may help control behavioral symptoms of AD such as sleeplessness, agitation, wandering, anxiety, and depression. Treating these symptoms often makes patients more comfortable and makes their care easier for caregivers.