No use for private individuals
Blood test reliably detects Alzheimer’s
02/25/2022, 12:50 p.m
Several methods are still needed to reliably diagnose Alzheimer’s. Some of these are very expensive and invasive. A newly developed blood test, already approved in the US, might change that.
For years there has been a search for an inexpensive and simple test to diagnose Alzheimer’s. Researchers have now succeeded in developing a blood test that shows the proteins responsible for Alzheimer’s, the so-called beta-amyloids, with high precision. Specifically, these are Abeta 42 and Abeta 40, writes the research team to the study resultswhich were published in the journal “Neurology”.
This is possible because small amounts of beta-amyloids also get into the blood via the cerebrospinal fluid, the so-called cerebrospinal fluid. However, puncture of the spinal cord to diagnose Alzheimer’s is a relatively invasive and expensive procedure that carries risks.
The reliability of the new test, which has already been approved in the USA, was examined in a study involving a total of 464 study participants from Australia, the USA and Sweden. The result of the test was then provided in the respective countries with the result of the so-called positron emission tomography (PET). With this, the blood flow in the brain is examined with the help of a weakly radioactive substance. The study participants were people with and without cognitive impairments.
Knowledge of risk is questionable for private individuals
In practice, PET is rarely used to diagnose Alzheimer’s. The examination with costs of 5000 to 8000 dollars is very expensive and only a few clinics or practices are equipped with these devices. Another point: There is no reason for the expensive diagnosis, since there is currently no therapy that can really cure Alzheimer’s or stop it permanently. The approval of the active substance aducanumab in the USA, whose effect is controversial, has not changed this.
With the blood test, in combination with genetic risk factors, 93 percent of people with an increased risk of Alzheimer’s can be identified, writes the Washington University School of Medicine in St. Louis in a message. However, the use of the blood test for private individuals, which is on the market in the USA for around 500 dollars, remains questionable given the lack of treatment options.
In the future, however, it might serve well for research and be used, for example, to find subjects for Alzheimer’s studies. With the help of the blood test, it would be possible to identify with high precision those who already have the changes in the brain that are typical of Alzheimer’s, even before they develop symptoms.