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Dementia Overview

        Health | Dementia

Dementia Diagnosis
A doctor can help you determine if that string around your finger is the onset of dementia.
A doctor can help you determine if that string around your finger is the onset of dementia.
Ann Cutting/Photonica/Getty Images

Dementia usually begins slowly and worsens over time, so it may be difficult to pick up on the earliest symptoms. As we mentioned earlier, some memory loss is to be expected as a person ages, so diagnosing dementia requires that doctors distinguish between normal age-related forgetfulness, mild cognitive impairment (an intermediate stage of cognitive decline not quite severe enough to be classified as dementia) and dementia.

To think about the difference between these stages, consider the task of remembering that the garbage is picked up on Tuesdays, and all trash and recycling needs to be put on the curb by then. A person exhibiting memory impairment typical of advancing age may occasionally forget to do this. A person exhibiting mild cognitive impairment may not only forget to take out the trash, but also may forget that a doctor's appointment and a grandchild's birthday are on Tuesday. A person with dementia may not even realize that it is Tuesday.

Another distinction between these levels of memory decline is that those with more severe cases usually don't realize there's a problem. If you're aware that you're forgetting things, that's something of a good sign. In the case of dementia, then, it may take someone close to the person exhibiting symptoms to get him or her to the doctor for an official diagnosis.

With so many types of dementia, a proper diagnosis may seem like a game of elimination. Doctors begin evaluating patients from the moment they walk in the door, looking for clues from the patients' appearance, behavior, speech, mood, motor skills and thought processes. The appointment usually starts with an interview; it's especially helpful if someone who has witnessed the cognitive decline is present to provide examples. Understanding a patient's history will provide some context to the symptoms; for example, if the patient has trouble reading and comprehending but is a former English teacher, that's particularly telling, as is a person who was once meticulous in appearance refusing to take a shower or change clothes.

Doctors will also, of course, try to determine exactly what parts of the brain are affected. One of the most common ways to do so is by administering brief cognitive tests. One example is the Mini-Mental State Examination (MMSE). In conducting the MMSE, the doctor will ask the patient some basic questions and to perform several mental tasks, such as counting backward or repeating words in order. To score the MMSE, the doctor assigns points for correct answers and adjusts for education level. Scores in certain ranges on a pre-set scale indicate dementia.

Doctors may administer another quick exam known as the clock drawing test. The patient is asked to draw a clock so that it says a certain time. Although the task might sound easy, it draws upon many areas of the brain to complete correctly. Based on how the final drawing looks, doctors may be able to sense exactly which areas are compromised. Doctors will also use brain imaging scans to look for signs of a stroke or a brain tumor; in the case of vascular dementia, the lesions left by the stroke will be seen on the brain.

Throughout the exam, doctors will be looking for conditions that affect the mind that may be reversible. Memory loss can occur as a side effect of some medications, and it's also associated with depression and medical conditions such as brain tumors and vitamin deficiencies. In these cases, correcting the cause will usually address the symptoms of dementia.

Do doctors have any treatment options when irreversible dementia is diagnosed? Find out on the next page.


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