Visit Your Local PBS Station PBS Home PBS Home Programs A-Z TV Schedules Watch Video Donate Shop PBS Search PBS
skip navigation

in diagnosis

related info

Diagnosis: testing

People with severe memory problems are usually not eager to seek testing. But for people in the early stages, there is a greater awareness of the value of early diagnosis and increasingly, people are seeking out testing to investigate their memory problems. It’s important to be prepared before you visit your doctor. Make a list of questions to maximize the visit. Bring a family member or loved one with you.

What to Expect

No single test can diagnose Alzheimer's disease. Doctors use many different tools to determine whether someone has the disease, but in most cases, physicians begin with a memory and performance test like the MMSE (Mini-Mental State Examination). The MMSE serves as a quick screening tool for dementia of any kind.

The MMSE tests a person's ability to understand, remember, communicate and think using questions like:
What is today's date?
What day of the week is it?
What is the season?
What state are we in?
What city?

The MMSE was developed more than 30 years ago. In the very earliest stages, it may not be sensitive enough for an accurate diagnosis of very early stage Alzheimer's, especially for someone with extremely high intelligence and mental capacity. They may almost be able to appear normal while undergoing this screening test. But, the MMSE is the best place to start, and it is usually a useful test. Doctors should adjust “normal” scores based on education and age, thereby customizing the test for each individual patient.

Other Testing Tools

Physical exams, psychological tests and a patient's medical history are also crucial to the diagnostic process. Someone familiar with recent events should accompany the patient to the office. The history of memory loss progression is an important piece of the diagnosis.

If results are still unclear, brain imaging such as CAT scans or MRI scans can help rule out other possible causes. Sophisticated brain scans like PET scans can identify activity decreases in hippocampus activity, the first part of the brain attacked by Alzheimer's. In fact, the hippocampus actually shrinks early in Alzheimer's disease.  

Before the Test

Before you visit your doctor, it’s important to prepare for the visit. Someone should accompany you to the appointment. Make a list of all the changes you have noticed. Ask yourself these questions:

  1. Are you having trouble performing tasks you’ve done all your life, like cooking or balancing the checkbook?
  2. Is it difficult for you to remember the names of common objects, like keys or coins?
  3. What medications are you taking? (Include prescription drugs, herbal supplements, vitamins and over-the-counter products.)
  4. Have you gained or lost weight recently?
  5. Have you had any bouts of vomiting, diarrhea or heat exhaustion? (Dehydration and malnutrition can cause memory loss or dizziness.)
  6. How much alcohol do you drink on a regular basis? 

What to Expect

  1. A discussion with your doctor about your medical history and family health history.
  2. Mental evaluations to test your sense of time and place, memory, reasoning, coordination, language skills, balance and other brain functions. You may be asked to put together a puzzle, draw a pattern with a pencil and paper or remember words and phrases.
  3. Physical tests, including brain scans, blood and urine tests, and an exam to look at nutrition, pulse and blood pressure.
  4. A psychiatric evaluation, to look for depression or other conditions that could be causing your symptoms.

Questions to Ask

If you have gained or lost more than 10 pounds recently, ask your doctor to check your medication levels, to make sure that you are not taking too much or too little of any medications you may have been prescribed. Also, because depression can sometimes be mistaken for dementia, you should ask your doctor to be screened for possible depression.

Types of Tests to Anticipate

A workup will involve many parts, including mental and psychiatric evaluations and physical tests. Ask your doctor exactly what will be involved in the testing. The types and number of tests your doctor will perform depends on the level of the memory problem, family and medical history, and results from any previous tests. How long will the tests take? When will you learn the results? 

According to Lisa Gwyther, MSW, and P. Murali Doraiswamy, MD, with Tina Adler, authors of The Alzheimer's Action Plan, there are 16 core essential tests that are considered standard for someone who is suspected of having Alzheimer's. In some cases, the MMSE and medical history alone will confirm a diagnosis. If you have questions about specific tests, ask your doctor.

Core essential tests include:

  1. Interview with the family
  2. Check for inappropriate drugs
  3. Memory and medical history
  4. MMSE
  5. Clock test
  6. Depression screen, such as the Beck Scale, Geriatric Depression Scale
  7. Delayed recall memory test
  8. Physical, neurological exam, hearing, vision, smell, weight, blood pressure, waist measurement
  9. Vascular risk assessment
  10. Brain MRI or CT (MRI is preferred)
  11. Urine analysis
  12. Blood cell counts to look for infection or anemia
  13. Thyroid function with ultrasensitive TSH
  14. Blood tests for liver function, kidney function, electrolytes, glucose
  15. Fasting cholesterol and lipids blood test
  16. Vitamin B12 and folic acid blood test

From The Alzheimer's Action Plan by P. Murali Doraiswamy, MD, and Lisa P. Gwyther, MSW, with Tina Adler. Copyright (c) 2008 by the authors and reprinted by permission of St. Martin's Press.

What will the tests show?

By evaluating your health history, testing your memory, problem-solving and language abilities, and running medical tests and/or brain scans, doctors can make an accurate Alzheimer’s disease diagnosis nine out of ten times.

Ask your doctor to go over the test results with you.

If it’s not Alzheimer’s Disease, What Is It?

Other neurological diseases or infections could be causing the symptoms. Other possible causes of memory problems include overuse or underuse of medication, depression, alcohol abuse, poor nutrition, dehydration, thyroid problems, head injury, tumors, or heart or lung disease.

There are also many different types of dementia besides Alzheimer’s, including vascular dementia, dementia with Lewy bodies, and many people with Parkinson’s disease, another neurological disorder, develop dementia in late stages.

Ask your doctor whether these or other problems could be causing your symptoms.