When to see a doctor
Date Posted: May 1, 2008
In-Depth Report
When to see a doctor
If you're concerned about your memory, or if people close to you have noticed some worrisome trends, see your doctor for an exam. Because memory loss can be a symptom of many different medical problems, it's important to identify the cause and begin treatment as soon as possible. In some cases, treating a medical disorder or intervening with an emotional concern can lead to improvements in memory. For instance, people with depression or high blood pressure often find that treating those conditions restores their memory function or at least prevents further decline. If, on the other hand, you learn that your problem is normal age-related memory loss, you can relax, knowing that there is nothing wrong and that simple strategies and lifestyle changes can help strengthen your memory (see "Improving everyday memory").
The first step
Begin with a consultation with your primary care physician. Because this doctor knows you and your medical history, he or she is in a good position to relate your memory symptoms to medications you are taking and medical conditions you have had. But don't necessarily expect to walk out of your doctor's office with a definitive diagnosis. There is no single test that can pinpoint the cause of memory loss. The diagnostic process often requires a physical exam, a variety of tests, and, depending on the results, monitoring over a period of several months or even longer. Expect your doctor to ask you a lot of questions about your memory. For example:
How long have you been having problems?
Did the trouble come on gradually or suddenly?
What sorts of things have become hard to remember?
Are your difficulties preventing you from doing ordinary things like cooking or reading?
Are you taking any prescription or over-the-counter medications (other than those prescribed)?
These questions help the doctor narrow down the possible causes of your memory loss. For example, the doctor will need to know whether you are taking any medications that might have a known association with memory impairment. If your memory loss came on suddenly — shortly after taking a drug that is known to affect memory — then the diagnostic process may focus on that drug. Depending on the medication, the doctor may ask you to stop taking it or may prescribe a different drug to see whether your memory improves.
Your answers about the nature of your memory loss also provide important clues. If you're having trouble remembering the names of people you meet and you forgot a doctor's appointment, that suggests that the problems you're experiencing — however troublesome — probably fall in the normal range. But if your memory difficulties are forcing you to cut back on activities you once did regularly, the underlying cause may be something other than normal aging (see "Causes of memory impairment").
Because certain emotional and medical conditions can affect memory, the doctor will review your medical history, ask you about new symptoms and illnesses, and perform a physical exam. For example, the doctor will measure your blood pressure and blood sugar to look for hypertension or diabetes. If you have one of these conditions, your doctor can make sure that it is properly controlled, either with medication or through lifestyle adjustments, such as a modified diet. Your doctor may also check your blood and urine for signs of kidney or thyroid problems. The doctor may ask whether you've been under a lot of stress lately or if you've been feeling blue, because stress and depression can cause memory impairment as well as loss of interest in previously enjoyable activities. If depression is an issue, your doctor may refer you to a psychologist or a psychiatrist for further evaluation and treatment.
To reach a clear diagnosis, the doctor may need you to track your symptoms for several months, and so may ask you or your spouse to keep a record of your symptoms and then return to the office after that period. He or she can then determine if the symptoms are improving, staying the same, or getting worse.
Normal aging or dementia: A questionnaireHow do you know when memory loss is an early symptom of Alzheimer's disease or another type of dementia? There's no question that severe, progressive memory loss is a hallmark of dementia, but research suggests that forgetfulness alone is not a perfect predictor of Alzheimer's disease. Researchers at Harvard Medical School found that responses to eight standard clinical questions predicted with a high degree of accuracy whether people with memory impairment would remain stable, decline, or improve. The eight questions were derived from three categories: judgment and problem solving, home and hobbies, and personal care, as follows: Judgment and problem solving Do you have increased difficulty handling problems (e.g., are you relying more on others to help solve problems or make plans)? Is there a change in your pattern of driving that is not the result of vision problems (e.g., a greater degree of caution, trouble in making decisions, etc.)? Is your judgment less sound than it used to be? Are you having increased difficulty managing finances (e.g., maintaining a checkbook, paying bills, making complex financial decisions)? Are you having more difficulty handling emergencies? Have you been making unsafe decisions? Do you rely more on cues from other people in order to react appropriately? Home and hobbies Are you having increased difficulty performing household tasks, such as cooking or learning how to use new appliances? Has there been any change in your ability to pursue your hobbies? For example, do you spend less time on complex hobbies? Do you have more trouble following the rules of games? Do you read less, or do you need to reread more often in order to understand what you've read? Personal care Do you need prompting to shave or shower? Scoring: People in the study who answered yes to all of these questions were most likely to develop Alzheimer's within three years. The purpose of this quiz is to indicate if you have symptoms that warrant further evaluation. It is not intended to diagnose a memory disorder. If you answered yes to four or more of the above questions, see your physician. |
Neuropsychological testing
If your symptoms warrant a more comprehensive evaluation, your physician may refer you to a neuropsychologist, a doctor who specializes in the relationship between brain and behavior. A neuropsychological examination begins with a thorough review of your history as well as a review of the diagnostic studies and tests that you've already had. Neuropsychologists typically use a battery of paper-and-pencil tests of mental abilities to comprehensively evaluate your cognitive function. The tests assess attention, memory, executive functions, language, and spatial ability. The doctor may also use tests or questionnaires to gauge your mood. Not all neuropsychologists use the same tests, but they all look at this same spectrum of mental functions. A technician may help administer the tests.
The neuropsychologist will interpret and analyze the test results in light of your age, level of education, and other variables that influence cognitive ability and memory capacity, as well as in the context of your medical history and other diagnostic studies. That way, he or she can determine if the findings suggest a specific type of disorder or if they reflect normal age-related changes in cognitive function. The following are the kinds of tests that are used. Your doctor will probably refer you to a specialist for additional testing (which may include brain-imaging tests; see below) if your examination and initial test results suggest the possibility of a neurological or medical disorder.
Testing attention
Failure to pay close enough attention is one of the primary reasons people fail to learn new information — they never absorbed it completely in the first place. There are many tests that can be used to assess attention. In one example, the neuropsychologist might read you a sequence of numbers and then have you repeat back as many as you can remember.
Testing memory
Memory testing usually requires that you listen to or view some information and answer questions about it or reproduce it immediately afterward, and then again 10 to 30 minutes later. Some memory tests entail learning and remembering visual information, such as a picture that you were asked to study or a design you were asked to copy (see Figure 9). The neuropsychologist might also test your long-term memory by asking you questions about your personal history or factual information you may have learned in the past, comparing it to information gathered from medical records or other sources.
Figure 9: Draw this picture
A picture like this one is commonly used to evaluate visual memory. Study this illustration for 15 seconds and then put it away. Then draw as much of the picture as you can from memory. The better your visual memory, the more of the picture you will be able to reproduce. If after performing this test you are concerned about your memory, it is important to have an evaluation, as some causes of memory difficulty are treatable (see "The first step"). |
Testing executive functions
Executive functions are high-level mental functions that involve the overall regulation of thought and behavior, such as reasoning, problem solving, planning, initiation, inhibiting impulses, and resisting distraction in order to stay focused on a task. You use executive functions even when doing simple things like following a recipe. These functions are among the first to become impaired in people with Alzheimer's disease.
One assessment of executive functions is the Trail-Making Test. The first phase of this paper-and-pencil test shows circles, each with a number inside it. The test-taker must connect the circles in numerical order. On the second phase there are circles containing either a number or a letter. In this case, the test-taker connects the circles by alternating between the numbers and the letters: 1 to A to 2 to B, and so on. The test is scored according to speed and accuracy.
Executive functions are also important in appreciating the subtle, implicit rules that guide social interaction — for example, exhibiting normal consideration for others and the motivation to engage with them. People who are having difficulty in this area are often unaware of the problem; family members may be the first to notice a personality change. These types of problems with executive functions are usually not assessed through testing but rather through direct observation and discussion with family members.
Testing language
Language functions include the abilities to express yourself through speaking and writing and to understand what another person is saying or what you are reading. The neuropsychologist may ask you to name common objects or pictured items. Problems with naming and word finding can be early symptoms of Alzheimer's disease. You may be asked to follow instructions as a way of determining if you understand what's being said. You may also be asked to read a brief paragraph, repeat phrases, or describe a picture in writing.
Testing spatial ability
Spatial ability includes analyzing visual information such as shapes, faces, and routes between locations on a map. Because the right side of the brain plays a primary role in analyzing spatial information, people who are having difficulty with this type of function may have a condition that has damaged the right hemisphere, such as a stroke. Although it is relatively uncommon, there is a visual variant of Alzheimer's disease, which begins with symptoms that suggest right-sided or posterior brain dysfunction. Spatial ability tests include drawing and copying designs, solving maze puzzles, and putting blocks together to construct a specific pattern (see Figure 9).
Brain-imaging tests
A magnetic resonance imaging (MRI) or computed tomography (CT) scan produces a structural image of your brain (see "Watching the brain at work"). These imaging methods provide the most definitive method of identifying certain causes of memory problems, such as a brain tumor, hydrocephalus (an abnormal accumulation of cerebrospinal fluid within the ventricles of the brain), or a subdural hematoma (a collection of blood under the surface of the skull). All of these conditions cause increasing pressure within the brain, producing neurological and cognitive symptoms. Treatment for these conditions is often successful, particularly if they are detected early.
Watching the brain at workImprovements in brain-imaging technology have revolutionized what we know about how the brain remembers and where memories are stored. MRI and CT scans can show the shape, size, and contour of the brain and other aspects of internal anatomy. And since the 1980s, scientists have been able to trace the activity of the living, working brain with the help of functional imaging techniques such as single photon emission computed tomography (SPECT), positron emission tomography (PET), and functional magnetic resonance imaging (fMRI). These methods scan blood flow and track the brain's use of certain substances to show which parts of the brain are most active during a particular activity. MRI scans have revealed key structural differences between the brains of young people and old, and between old people with normal age-related memory loss and those with Alzheimer's disease. These tests have also illustrated that certain brain areas shrink in people with abnormal memory impairment from conditions such as Alzheimer's. SPECT and PET can help doctors identify regions with abnormally low blood flow or metabolic activity within key brain areas years before shrinkage of those areas is visible on a structural image from MRI. This type of technology disproved the long-held myth that memories are stored in just one "memory bank" in the brain. Instead, researchers could see diverse areas of the brain become activated as people learned and processed new information, and as they remembered things. Scientists determined that memory relies upon a widely distributed network of interconnected brain regions. SPECT and PET scanning have become useful in diagnosing Alzheimer's disease because they can reveal abnormal patterns of blood flow or energy metabolism in key brain regions that are affected early in the onset of the disease. Once confined to research studies, these tests have now become clinical tools for evaluating patients with cognitive symptoms. A specific type of PET scan, called FDG-PET, which maps glucose uptake in the brain, has gained wide acceptance as a way to differentiate Alzheimer's disease from normal aging and other dementias. The real promise of FDG-PET, however, may be in the ability to detect Alzheimer's based on reduced glucose metabolism in the brain as many as nine years before clinical symptoms appear. This knowledge is vital to the development of therapies that might halt the disease at a point when cognitive function can be preserved. FDG-PET is one of the imaging techniques explored in the NIH's five-year, $60 million Alzheimer's Disease Neuroimaging Initiative (ADNI), which began in 2004. Research at the University of Pittsburgh led to the development of a compound (Pittsburgh Compound B, or PIB) that, when used in conjunction with PET scanning, can reveal the pattern of amyloid deposition in the brain, one of the hallmarks of Alzheimer's disease. The ability to image amyloid in the living brain represents a major breakthrough in clinical diagnosis and in the evaluation of potential treatments. And with the introduction of a version of the PIB compound that stays active in the body for 120 minutes (versus just 20 minutes for the original), doctors hope that PIB can become a viable tool for diagnosing Alzheimer's-related brain changes in clinical as well as research settings. |
Review Date: 2008-05-01
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