May’s beginning, arrived in Brazil the first blood test to detect the risk of Alzheimer’s, one of the main types of dementia. It looks for traces of the protein beta-amyloidthat accumulates in the brains of those who have the disease.
The test has already passed the United States a month ago and was brought to Brazil by Dasa – company in the health sector. For the moment, the recommendation concerns people with mild cognitive impairment, suspected of dementia.
one on three people in this situation, mostly elderly people, have small forgetfulness, difficulty concentrating and other failures that progress to Alzheimer’s.
“It does not complete the diagnosis, but it can assist in medical management and avoid performing a lumbar puncture to collect CSF, a more invasive test that is used today to estimate amyloid plaque levels,” explains Gustavo Campana, medical director of Dasa.
Novelty is not (yet) covered by the agreements, the novelty is offered under medical prescription in the network of laboratories, for an amount of approximately R$ 1.5 thousand.
How is the exam conducted and what is it for?
The idea of this new method is to replace more complex procedures with less invasive methods. Like liquid biopsy, which can detect recurrences of cancer showing fragments of DNA tumor.
The technology for this examination is mass spectrometry. “This is a technological development that has been available for a few years, which makes it possible to see molecules in small concentrations in blood or in other biological samples”, specifies Campana.
At Alzheimer’s casesthe machine is programmed to detect two fractions of amyloid-beta protein – 40 and 42 – and only then calculate the ratio between them.
Neurologist Renata Faria Simm states that “beta-amyloid is considered the main biomarker of Alzheimer’s disease”. Moreover, he confirms that TAU proteinsare also implicated in disease progression.
How accurate is the test?
In a research conducted with the new methodology, with approximately 200 patients, it showed a sensitivity of 71% to catch individuals with alterations in the PET scana CT mode used to confirm the diagnosis of Alzheimer’s disease.
So, for every 100 individuals whose brains are compromised by the disease, 71 would be found by examination.
The more detailed results have not been published, they are scheduled for July, in the International Congress of the Alzheimer Association (AAIC), which takes place in California.
The importance of diagnosis
With the increase in life expectancy, medicine has sought ways to prevent and, if necessary, to repair faults of the mind that appear naturally with aging.
In some situations, these early deficiencies can mean treatable dementia. “It’s important to make that differentiation early, because they have different treatments, and Alzheimer’s itself will soon have drugs that can be used at that early stage,” Renata says.
How is the diagnosis today
Most cases are diagnosed based on symptoms, there is usually a decline in recent memory, in which the patient gets worse. gradually and slowly.
According to the complaints, the medical specialist – neurologist, psychiatrist or geriatrician – performs functional tests to know the degree of commitment. Helped by an image of the brain, via MRI or CT scan, and blood tests that can rule out other non-neurological changes.
*With information from Veja Saúde