Diagnosis of Alzheimer Disease
Your doctor will ask about your symptoms and medical history. A physical exam will be done. This includes a thorough neurological evaluation along with a series of tests. Other tests may include those which will increase or decrease the likelihood that you have Alzheimer disease. Your doctor will also perform tests to eliminate the possibility of other conditions causing the dementia.
Tests to Assess Dementia
These tests help determine if you have signs of dementia, how severe the dementia is, or to look for other causes of dementia. They may include:
Neurological exam—examines the nervous system for evidence of other neurological disorders. This may include mental status testing of:
- Sense of time and place
- Problem-solving abilities
- Attention span
- Language skills
- Visual-spatial perception
- Learning capacity
- Decision-making skills
- Psychological evaluation—looks for depression or other emotional illnesses that may be the first sign of Alzheimer disease
- Imaging tests, such as
PET scans—to evaluate the brain for any abnormalities
Lumbar puncture—tests the fluid surrounding the brain and spinal cord to look for infections that can cause dementia, or show markers of Alzheimer, such as beta amyloid and tau proteins
is a test that evaluates and follows the electrical activity of the brain. It is not a common test for evaluating most dementias, but it may be done.
Blood and Urine Tests
Blood and urine tests may be ordered to look for other conditions that cause dementia. The tests may include:
- Thyroid function tests
- Complete blood count (CBC)
- Levels of vitamins (including B vitamins)
- Erythrocyte sedimentation rate (ESR)
- Vasculitis work up
Genetic tests can look for markers that increase your risk for early-onset Alzheimer. Your doctor may recommend this test if you have family members with this condition.
An Alzheimer disease diagnosis usually falls into one of three categories:
- Probable Alzheimer disease—This indicates that other dementia-related disorders have likely been ruled out. The symptoms are most likely due to Alzheimer disease. At least 2 areas of cognition are affected. One area is a worsening of memory.
- Possible Alzheimer disease—The dementia is possibly caused by Alzheimer disease. There may be other disorders that are causing the dementia.
- Definite Alzheimer disease—This diagnosis can only be made at the time of death. It is done through an autopsy when the brain tissue can be examined. This is the only way to diagnose the disease with complete certainty.
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What is Alzheimer's?
Alzheimer’s Association website. Available at:
http://www.alz.org/alzheimers%5Fdisease%5Fwhat%5Fis%5Falzheimers.asp. Accessed October 2, 2017.
9/3/2014 DynaMed's Systematic Literature Surveillance. Available at:
http://www.dynamed.com/topics/dmp~AN~T114193/Alzheimer-dementia: Wippold FJ, Brown DC, Broderick DF, et al. American College of Radiology (ACR) Appropriateness Criteria for dementia and movement disorders. Available at: http://www.acr.org/~/media/ACR/Documents/AppCriteria/Diagnostic/DementiaAndMovementDisorders.pdf. Updated 2014. Accessed September 3, 2014.
EBSCO Medical Review Board Rimas Lukas, MD
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