Jun 27, 2009
(Editor’s Note: I recently came across an excellent book and resource, The Alzheimer’s Action Plan: The Experts’ Guide to the Best Diagnosis and Treatment for Memory Problems, recently released in paperback. Dr. Murali Doraiswamy, one of the authors and leading Alzheimer’s expert, kindly helped us create a 2-part article series to share with SharpBrains readers advice on a very important question, “How can we help the public at large to distinguish Alzheimer’s Disease from normal aging — so that an interest in early identification doesn’t translate into unneeded worries?” What follows is an excerpt from the book, pages 72–78, discussing the Pros and Cons of the most common assessments).
While no single test (other than a brain biopsy, which is a very invasive and risky procedure) can conclusively prove that a person has Alzheimer’s, many tests can give us a good idea. A list of all the tests that help us assess memory and thinking problems appears at the end of this chapter. Meanwhile, let’s take a good look at the whys and hows of a thorough memory assessment.
WHAT A DIFFERENCE AN EXTRA TEST CAN MAKE
To understand why getting tested (and retested as symptoms change and the disease progresses) is important, check out the experience of Katherine, who went to the doctor complaining of a memory slowdown. She took five of the most important neuropsychological tests, which assess brain function without actually physically looking at the brain. Then she underwent brain scans, a cardiovascular workup, and blood tests to see what else was going on that might be undermining her mental function.
- BUT FIRST, PAYING FOR THE DIAGNOSIS–
Ignorance can be costly, yet so is information. At the first visit, ask the doctor to spell out which tests he or she wants to run, then check that your insurance covers those tests and whether there are any conditions that are not covered. At the end of this chapter you will find the approximate costs of different tests.
Was it all worth it? Well, if she had stopped at just the two most common tests, she could have walked away with a very inaccurate diagnosis.
First, the doctor wanted to know if she had a family history of Alzheimer’s and, if so, at what age the relative developed Alzheimer’s. The doctor also needed to know her age. That’s not surprising—seems the older you get, the more people ask. But for an Alzheimer’s diagnosis, age really matters, because after age sixtyfive the risk of Alzheimer’s doubles every five years, and below age fifty the disease is relatively rare.Your education level is important, too. People who didn’t complete high school have a greater risk of developing Alzheimer’s than people with a higher level of education. Finally, women are more likely to get Alzheimer’s than men.
Katherine was seventy-two, a college grad, and had no family history that she knew of.Her parents both died before their seventy-fifth birthdays, but they certainly didn’t have early-onset Alzheimer’s.
THE STANDARD OF MEMORY TESTS
The test that all doctors should give at the first memory assessment, which Katherine’s doctor did, and at every follow-up visit is the Mini-Mental State Exam (MMSE), a short but very useful test that assesses a lot of different abilities.
- To demonstrate orientation:The patient tries to answer, “What is today’s date?” and “What county are we in?”
- To demonstrate memory skills: The patient tries to repeat the names of three objects immediately and again after five minutes.
- To demonstrate concentration: The patient tries to count backward or to spell backward.
- To demonstrate language abilities: The patient tries to name objects in the room, repeat a tongue twister, or follow simple directions such as to take, fold, and put a piece of paper on the desk.
- To demonstrate motor skills: The patient tries to copy a picture that includes intersecting shapes.
- Serves as a quick screen for dementia of any kind
- Provides a general measure of brain function
- Helps determine if the patient is in the early, middle, or late stage of Alzheimer’s
- Monitors changes in mental functioning over time, including the effects of treatment
- Provides a common language. Everyone from a general practitioner to a memory specialist understands the test results, so they serve as a common language spoken across different specialties.
What the MMSE Doesn’t Do
The MMSE doesn’t do subtle. It was developed thirty years ago to help doctors screen hospital patients for problems with their mental functioning. Now people are driving themselves to the doctor for a memory test, and the MMSE is not sensitive enough to pick up on subtle problems in thinking and memory. Nor does it probe any one aspect of mental functioning in depth or distinguish among memory disorders.
Some individuals with a very high IQ or those who are really good test takers appear merely “normal” on the MMSE when in fact they have an Alzheimer’s-induced memory slowdown. Doctors should, though not all do, consider IQ, gender, occupation, education level, and an individual’s age when scoring the MMSE. An assessment may not include a formal IQ test, but the doctor should find out about the person’s personality, capabilities, and occupation prior to developing memory problems, because Alzheimer’s is about a decline or change in memory and thinking. For example, the MMSE score of 26 is normal for a man in his early sixties who has an eighth-grade education, but it would be below normal if he had gone to college. (A chart showing what MMSE score is normal for a person’s age and education is available at www.tuftsnemc.org/ psych/mmse.asp.)
Katherine did okay on her MMSE. She scored a respectable 26 out of a possible 30. No big red flag there for most doctors, who don’t worry until they see a total score below 24. But the score actually concerned her doctor, who happened to know that for her years of education and age, normal for Katherine would be closer to a 28.
Doctors sometimes neglect to home in on how the test taker did on each set of questions. For example, forgetting today’s date is less important than missing other assessment questions. Before leaving the doctor’s office, find out your (or your relative’s) total MMSE score and what items were missed.
Katherine ended up taking the MMSE many times over the years. Her scores declined slowly because, as the tests revealed, she had MCI (mild cognitive impairment). But after three years, she, too,was diagnosed with Alzheimer’s and her decline accelerated.
It’s Time …
Probably the second most popular test to screen for dementia is the clock-drawing test, which requires patients to draw a clock showing a specific time. The test is a good way to screen for overall mental abilities, and it can reveal problems that the patient has been able to hide during day-to-day activities. Katherine did great on the test, which was lucky for her daughter, whose own little girl was just mastering the skill of telling time. It’s upsetting for family members to see a parent or spouse fail at a task most kids master in grade school.
Most general practitioners consider talking with the patient, ordering some blood tests and a brain scan, and giving the MMSE and clock-drawing test sufficient for diagnosing dementia. It might be sufficient for someone with obvious signs of Alzheimer’s. But it could miss the early-stage Alzheimer’s or MCI. Fortunately for Katherine and her family, her doctor did more.
ASSESSING LANGUAGE SKILLS
A diagnosis of Alzheimer’s requires being impaired in memory and one other mental function, such as language or attention. Language problems usually indicate that Alzheimer’s is somewhat progressed or that the problem is another type of dementia that strikes the language centers of the brain first.
To assess language, beyond just listening to how the person formulates and understands words, a doctor will ask the patient to name common objects, such as chair, shoe, or elbow. More sensitive tests of language skills involve asking the patient to name, for example, all the four-legged animals he or she can think of as quickly as possible, or to repeat complex phrases, such as “Nelson Rockefeller had a Lincoln Continental.” Katherine took one section of a language test called the Boston Naming Test that required her to name uncommon objects depicted in line drawings. She got only twentysix out of thirty right, which is slightly worrisome.
The Delayed Recall Test
One of the most sensitive tests to distinguish normal aging from Alzheimer’s is the delayed recall test, which tests a person’s memory for a story or list of ten to sixteen words heard thirty minutes earlier. It’s usually given as part of a larger memory test that also assesses immediate recall. Katherine’s MCI came out of the shadows here. She was in the bottom nineteenth percentile on these recall tests.
One delayed recall test, called the Buscke Selective Reminding test, helps distinguish Alzheimer’s from normal aging, because the tester is allowed to give clues to jog the test taker’s memory. A prompt usually does not help if Alzheimer’s is at the wheel, but it does help if the memory malfunction is due to depression or attention grabbers.
There are other tests, too. To assess attention, doctors see how well the patient can follow directions. They also ask the patient to spell words forward and backward or to subtract numbers forward and backward (for example, subtract by 7s starting at 100). There are computerized tests of attention as well, which are becoming increasingly popular in private practices and research centers.
The activities once taken for granted, from using the phone to fixing dinner, go from routine to frustrating to impossible as Alzheimer’s storms the brain. Katherine’s doctor used a Functional Activities Questionnaire (FAQ) to rate her ability to perform several common daily activities. The questionnaire assigns one point if a person has trouble with the activity but can do it alone, two points if he or she needs assistance, and three points if he or she is dependent on someone else to do it. The highest score, 30, indicates impairment in all activities; a score below 9 is normal. Katherine scored a 5, because she needs some help balancing her checkbook and assembling tax records.
DEPRESSION, DEMENTIA, OR BOTH?
Depression is a must-check condition for every person complaining of impaired thinking. Depression and Alzheimer’s have an insidious relationship: Depression masks Alzheimer’s, is mistaken for Alzheimer’s, worsens Alzheimer’s, may precede the onset of Alzheimer’s, and can be caused by Alzheimer’s. To screen for depression, the doctor may start by just asking a few important questions:
1. Are you able to have fun or experience pleasure during a normal day?
2. Are you sleeping well?
3. Are you in pain?
4. Is everything okay with home and family life?
5. Have you lost weight unintentionally? Are you overeating?
Katherine’s answers were: 1. not really; 2. not really; 3. not really; 4. I don’t have much of a home life;
5. I wish.
Her doctor decided to give her the Geriatric Depression Scale— Short Form, which asks fifteen questions to probe for depression. A score greater than 5 warrants further assessment and a score greater than 10 indicates clinical depression. Katherine scored 11.After asking a few more questions and reviewing her medical record, the doctor prescribed an antidepressant. He also recommended that her family get her more involved in physical and social activities, including walking. Three months later, her depression eased. Her memory problems persisted, but she was thinking more clearly and her attention and concentration improved. Also, she regained a good portion of her former desire to see her friends.
Doctors often give the relative of the person with Alzheimer’s the brief Neuropsychiatric Inventory (NPI) to assess changes in the patient’s sleeping and eating habits, appetite, depression, euphoria, irritability, hallucinations, paranoia, impulsivity, and nighttime behaviors.
The family member also describes how much each of these behaviors is disrupting the family.To fill out the survey, family members can rely on their memory or keep a weekly diary of changes they notice in the person with Alzheimer’s.The NPI can help a doctor:
- Be more thorough. Unusual symptoms, such as extreme euphoria or impulsivity, may point to frontal lobe dementia, for example.
- Determine if the person needs psychiatric drugs, such as antidepressants
- Identify the stage of Alzheimer’s—more severe behavior problems usually indicate more advanced dementia
- Monitor improvements following the start of new medications (such as Aricept or Namenda)
This scale is particularly useful if one is being treated by a nonspecialist, since most general practitioners often lack the time or experience to assess behavioral problems in detail. Doctors use the NPI when first assessing a patient and again at subsequent appointments to monitor change. Roughly one-third of people with MCI and two thirds of people with mild to moderate Alzheimer’s have a behavioral change.
Computerized Neuropsychological Tests
For people with mild memory loss, computerized tests of all aspects of mental functioning, including memory, are particularly useful though not widely used. Unlike paper-and-pencil tests, computerized assessments can easily be made more difficult to challenge patients who are only slightly impaired or who are highly able test takers. Computerized tests are becoming very feasible to administer, as more patients (though not all) are becoming more technology savvy and comfortable with a keyboard. You probably have to go to a specialist to take them, however, as they are not readily available elsewhere.
…(to continue reading, check out The Alzheimer’s Action Plan: The Experts’ Guide to the Best Diagnosis and Treatment for Memory Problems).