Thursday March 05, 2020
–
For many years, Alzheimer’s could only be diagnosed beyond doubt after the patient’s death. Diagnostic methods currently used are complex or invasive. A new blood test gives hope for a simpler procedure in the future.
Alzheimer’s develops gradually over the years. Early treatment is important to prevent the disease from progressing as well as possible. Researchers have therefore started to look for clear indications of Alzheimer’s in the blood of patients. They discovered a component in the blood plasma that was on average 3.5 times higher in Alzheimer’s patients than in healthy people. It is part of the so-called tau protein and is called P-tau181.
The reliability of this blood test has already been tested in two tests in San Francisco (USA) and in Lund, Sweden, on a total of 951 people. The results of both studies were published in the “Natur Medicine” magazine. In addition to the high diagnostic accuracy, the research team led by Adam Boxer from the Weill Institute for Neuroscience in San Francisco also found that the test can even be used to distinguish it from so-called frontotemporal dementia. This rather rare disease also leads to deposits in the brain, which results in an increase in P-tau181. However, this is not as pronounced in frontotemporal dementia as in Alzheimer’s patients.
Plaques and dew fibrils
So far, experts do not know exactly what causes brain degradation in Alzheimer’s patients. However, it is certain that two different protein deposits play a role. These are so-called beta amyloid plaques and tau fibrils. Beta amyloid plaques accumulate outside the nerve cell. Tau fibrils, on the other hand, are altered accumulations of tau proteins within the nerve cell. The Tau proteins are chemically changed in Alzheimer’s disease. They therefore lose their shape and their functions and eventually disintegrate. Both changes disrupt communication in and between the nerve cells.
Even if the results of the US researchers on the Alzheimer’s blood test have already been largely confirmed by the Swedish research team led by Oskar Hansson from the University of Lund, further tests are necessary before final approval. According to the researchers, “the introduction of the test can therefore only be expected in about 5 years,” writes the Deutsche Ärzteblatt.
– ,
