Making an Alzheimer's diagnosis in the early stages will offer the best opportunity to treat related symptoms. An early diagnosis will also help patients and their families plan for the future while the person is still able to participate in the decision-making process. Tests that doctors use when diagnosing Alzheimer's include memory tests, medical tests, and brain scans.
Today, the only definite way to diagnose Alzheimer's disease is to find out whether there are plaques and tangles in brain tissue. However, to look at brain tissue, doctors usually must wait until they do an autopsy, which is an examination of the body that is done after a person dies. Therefore, doctors can only make a diagnosis of "possible" or "probable" Alzheimer's disease while the person is still alive.
At specialized centers, doctors can correctly make an Alzheimer's diagnosis up to 90 percent of the time. Several tools are used to determine if a person has this disease, including:
- Tests of memory, problem solving, attention, counting, and language
- Medical tests, such as tests of blood, urine, or spinal fluid
- Brain scans
- Questions about the person's general health, past medical problems, and ability to carry out daily activities.
Sometimes, these test results help the doctor find other possible causes of the person's symptoms. Other conditions that have symptoms similar to Alzheimer's include:
- Thyroid problems
- Drug reactions
- Brain tumors
- Blood vessel disease in the brain.
Some of these other conditions can be treated successfully.