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New simple blood test developed for the early detection of Alzheimer's


Great success in Alzheimer's diagnostics

There is currently no really convincing treatment option against the widespread Alzheimer's disease. According to experts, this is primarily due to the fact that the disease can only be diagnosed at a late stage with the current methods. At this stage, brain damage is well advanced and irreversible. This is now to be changed by a new type of blood test, which should even be suitable for routine use by a wide range of people.

According to the physicians, the new blood test can identify Alzheimer's on average eight years before the current diagnostic options. A team of scientists from the Ruhr University Bochum (RUB), the German Cancer Research Center (DKFZ) and the Saarland Cancer Registry showed this in a large cohort study. The underlying study of this blood test was published in 2017. Now the doctors are reporting on the subject with news.

Detect Alzheimer's eight years earlier

"Our simple and inexpensive blood test can detect the disease at an asymptomatic stage," reports Professor Dr. Klaus Gerwert of the RUB and coordinator of the research consortium "PURE" in a press release. In addition, the blood test can identify people who are at particularly high risk of developing Alzheimer's.

Blood test opens up new therapeutic approaches

“Drugs that are currently being tested in clinical trials may stop the disease from progressing if used at this early stage,” explains Professor Dr. Hermann Brenner from the DKFZ, Head of Department of Clinical Epidemiology and Aging Research. The development of new therapeutic approaches could benefit enormously from this blood test for early detection.

Dementia is an increasing problem

"Dementia is on the increase and presents those affected, relatives and society with enormous challenges," reports Monika Bachmann, the Saarland Minister for Social Affairs, Health, Women and Family. The minister is an active participant in the cohort study.

How does the new test work?

In the development of Alzheimer's disease, misfolds of the protein amyloid-β are involved, which are deposited as clumps in the brain (amyloid plaque). This process begins 15 to 20 years before the first symptoms appear. Klaus Gerwert's team succeeded in developing a blood test that can detect this plaque in the blood. When evaluating the test, the ratio of healthy to pathological forms of the amyloid β proteins can be determined.

Previous diagnostic options are expensive and complex

Until now, Alzheimer's could only be diagnosed at an early stage using expensive imaging methods such as positron emission tomography (PET) or using modified biomarkers in the spinal fluid. However, since these procedures remain complex and expensive, they are not suitable for screening large population groups.

The blood test doesn't have to shy away from the comparison

The new, comparatively uncomplicated blood test performed well when compared with the complex diagnostic procedures. In 70 percent of the cases, the new test identified those who later developed Alzheimer's. However, there was also an error rate of nine percent. The doctors call these results "false positive".

Solitary use not yet possible

"Because of the false positive results, the test is currently not suitable for the early diagnosis of Alzheimer's alone," says Gerwert. But it opens up the possibility of filtering out people in a cost-effective and minimally invasive screening who should then undergo further expensive and invasive diagnosis that can rule out a false positive result.

Infrared sensor enables the test

The blood test is based on so-called immuno-infrared sensor technology. The differently folded amyloid-β proteins absorb infrared light at different frequencies. This enables the sensor to determine the ratio of healthy to pathological amyloid-β in the sample.

In the future, the test should be suitable for routine use

Gerwert and his team are currently working intensively on technical improvements to the sensor in order to filter out even more sufferers and to minimize the rate of false positive test results. The research team wants to improve the process to such an extent that the blood test device is no larger than a box of chocolates and delivers results that are so good that it is suitable for routine use. (vb)

Author and source information

Video: Alzheimers disease can be detected by blood test (August 2020).