evaluations and tests

Determination of Medical History

The person being tested and family members will be interviewed both individually and together to gather background information on the person’s daily functioning, current mental and physical conditions, and family medical history.

Mental Status Evaluation

During the mental status evaluation, the person’s sense of time and place, and ability to remember, understand, talk and do simple calculations will be assessed. The person may be asked questions such as: “What year is it?” “What day of the week is it?” “Who is the current president?” The person will also be asked to complete mental exercises, such as spelling a word backwards, writing a sentence, or copying a design. When reviewing the test results, the physician will consider the individual’s overall performance in relation to his or her educational background and occupation.

Physical Examination

During the physical exam, the physician will evaluate the person’s nutritional status and check blood pressure and pulse. The physician will also search for the presence of cardiac, respiratory, liver, kidney and thyroid diseases, and arteriosclerosis (hardening of the arteries). Some of these conditions can cause dementia-like symptoms.

Neurological Exam

A physician, usually a neurologist, will closely evaluate the person’s nervous system for problems that may signal brain disorders other than Alzheimer’s disease. The physician will search for evidence of previous strokes, Parkinson’s disease, hydrocephalus (fluid accumulation in the brain), a brain tumor, and other illnesses that impair memory and/or thinking. The physician will learn about the health of the brain by testing coordination, muscle tone and strength, eye movement, speech and sensation. For example, the physician will test reflexes by tapping the knee, check the person’s ability to sense feeling on their hands and feet, and listen for slurred speech.

Laboratory Tests

A variety of laboratory tests will be ordered by the physician to help diagnose Alzheimer’s disease by ruling out other disorders. A complete blood count and blood chemistry will be ordered to detect anemia, infection, diabetes, and kidney and liver disorders. Levels of vitamin B-12 and folic acid (a vitamin produced by the body) will be measured, as low levels can be associated with dementia. Since very high or low amounts of the thyroid hormone can cause confusion or dementia, levels of the thyroid hormone are measured through a blood test. In addition, a serology test, urinalysis, electro-cardiogram (EKG), and chest x-ray may be ordered.

The physician may also order an EEG (electroencephalogram) to detect abnormal brain wave activity. This test can detect conditions such as epilepsy, which can sometimes cause prolonged mild seizures that leave a person in a confused state.

ACT (computerized tomography) scan, which takes x-ray images of the brain, is also frequently used. The brain is scanned for evidence of tumors, strokes, blood clots and hydrocephalus. MRI (magnetic resonance imaging) is another brain-imaging technique sometimes used. More experimental tests may also be recommended but are not necessary for the diagnosis. These include PET (positron emission tomography), which shows how different areas of the brain respond when the person is asked to perform different activities, such as reading, listening to music, or talking; and SPECT (single proton emission computed tomography), which shows how blood is circulating to the brain.

A lumbar puncture (or spinal tap) may be ordered if infection is suspected.

Psychiatric, Psychological And Other Evaluations

A psychiatric evaluation can rule out the presence of other illnesses, such as depression, which can result in memory loss similar to dementia of the Alzheimer type. Neuropsychological testing may also be done to test memory, reasoning, writing, vision-motor coordination and ability to express ideas. These tests may take several hours, and may involve interviews with a psychologist, as well as written tests. These tests provide more in-depth information than the mental status evaluation.

Nurses and occupational, rehabilitation or physical therapists may be called upon to look for problems with memory, reasoning, language and judgment affecting the person’s daily functioning.