Diagnostics
In order to be able to diagnose dementia medically, it is particularly important that the patient comes to the doctor with at least one close relative. The patients themselves often do not notice their cognitive impairment at all. However, close relatives who have known the patient for a very long time can often report well on what has changed in the patient’s behaviour.
It is important to determine to what extent the forgetfulness in question is pathological. Healthy people can also forget something without suffering from dementia. Imaging techniques (CT, MRT) are used to rule out disorders as the cause of the complaints that affect the brain.
A blood sample is taken to determine whether the patient’s bodily functions are in order. Various tests are already available to the family doctor who can perform them on a dementia patient in question. These include the Mini Mental Status Test (MMST), the watch test and the DemTect.
These tests test different abilities of the patient, such as memory, concentration, word fluency and verbal memory. In the early stages of dementia, however, these tests can be negative. They are not very sensitive to mild cognitive impairment.
Thanks to many innovations in research and the development of modern methods, many dementias can now also be diagnosed earlier in imaging. Alzheimer’s dementia, for example, manifests itself at an early stage by a decrease in brain mass in a certain area of the brain where memory is located. The different forms of dementia have certain characteristics that can be made visible in imaging, for example they can be distinguished in part by different limitations of the sugar metabolism in the brain.
Different test methods can be used to diagnose dementia. One example is the so-called clock test. The patient is given a piece of paper with an empty circle on it and is now asked to turn the circle into a clock.
Dementia patients often make characteristic mistakes when painting the clock. Some patients write more or less than 12 numbers in the clock, position the numbers incorrectly in the circle, forget the hands or paint something completely different into the circle. Another test is the Mini Mental Status Test (MMST).
This is a compilation of different questions designed to cover different competencies of the patient. These range from spatial, temporal and personal orientation, to memory, concentration and arithmetic, to more abstract skills such as drawing a geometric figure from a sheet of paper. For each correctly completed task, the patient receives one point, which is added at the end of the test to give a total.
A maximum of 30 points can be achieved. A score of less than 26 points indicates mild dementia, 19 points indicates moderate dementia and 9 points indicates severe dementia. Another frequently used test is the so-called DemTect.
It works similarly to the MMST. Here the maximum value is 18 points. Values below 8 points are considered to be manifest dementia.
