Ruhr-Universität Bochum (RUB) scientists have developed a two-tier method in detecting the early stage of Alzheimer. They published their study in the journal Alzheimer's and Dementia: Diagnosis, Assessment, and Disease Monitoring. Current methods can only detect Alzheimer's disease when plaques have formed in the brain.
"This has paved the way for early-stage therapy approaches, where the as yet inefficient drugs on which we had pinned our hopes may prove effective," says Professor Klaus Gerwert from the Department of Biophysics at RUB.
Klaus Gerwert and his team of researchers diagnosed the misfolding of the amyloid beta protein because of changes in pathology even before the onset of the first symptoms. This diagnosis can be done through a simple blood test. Thus, detection can be done eight years before the onset of the first symptoms. However, the team had to exert into optimizing the test as there are cases when false positive diagnoses for nine percent of the study participants.
This improved by introducing a two-tier diagnostic method. First, they used the original blood test. Second, they used tau protein, a dementia-specific biomarker, to determine if the patient really is positive with Alzheimer. There is a high likelihood of Alzheimer's disease if the two biomarkers showed a positive result.
"Through the combination of both analyses, 87 of 100 Alzheimer's patients were correctly identified in our study," summarises Klaus Gerwert. "And we reduced the number of false positive diagnoses in healthy subjects to 3 of 100. The second analysis is carried out in cerebrospinal fluid that is extracted from the spinal cord.
"Now, new clinical studies with test participants in very early stages of the disease can be launched," points out Gerwert. He is hoping that the existing therapeutic antibodies will still have an effect. "Recently, two major promising studies have failed, especially Crenezumab and Aducanumab - not least because it had probably already been too late by the time therapy was taken up. The new test opens up a new therapy window."
"Once amyloid plaques have formed, it seems that the disease can no longer be treated," says Dr. Andreas Nabers, head of the research group and co-developer of the Alzheimer's sensor. "If our attempts to arrest the progression of Alzheimer's fail, it will put a lot of strain on our society."
The RUB Department of Biophysics has fully automated the blood test process. "The sensor is easy to use, robust when it comes to fluctuation in concentration of biomarkers, and standardized," explains Andreas Nabers. "We are now conducting in-depth research to detect the second biomarker, namely tau protein, in the blood, in order to supply a solely blood-based test in future," concludes Klaus Gerwert.
