Alterations of memory, space-time disorientation, difficulty in reasoning, loss of initiative or problems to perform routine activities are some of the signs that should be taken into account when detecting a possible case of Alzheimer's. The diagnosis of the disease depends, precisely, on the coincidence of this series of clinical manifestations. Therefore, prevention is the most important factor of all: the sooner it is detected, the more chances there will be to delay its development.
Scientists at the University of Washington School of Medicine have discovered that with a simple blood test Signs of brain damage can be detected in people who are on the way to developing Alzheimer's. Even before they manifest the confusion and memory loss so characteristic. According to the study published in the journal Nature Medicine, this advance would allow identify brain injuries quickly and inexpensively both of this disease and others, such as multiple sclerosis or stroke.
"This is a test that could easily be incorporated into any neurological clinic," said Brian Gordon, professor of radiology at the Mallockrod Institute of Radiology and author of the research. "We have applied it to these patients because we know that their brains suffer a lot of neurogeneration, but this marker is not specific for Alzheimer's. The same alterations may reflect many other diseases and basic neurological injuries. "
Although there is no definitive statistics, the different associations of affected people calculate that, in Spain, there are 650,000 people over 65 suffer Alzheimer's, which translates into 7% of the population. While this is not a disease associated with aging, it is true that virtually all affected exceed this age. Because each year there are more than 100,000 new cases and taking into account the aging of the population and the future increase of people over 80, it is expected that the number of patients will double in 2020 and triple in 2050. Hence the The importance of moving forward on the path of eradicating this disease that, in the future, could pose a public health problem.
This test allows the detection of a chain of neurofilaments, a structural protein that is part of the internal skeleton of neurons. When these are damaged or die, this molecule filters into the cerebrospinal fluid that bathes the brain and spinal cord and, from there, enter the bloodstream. For experts, finding the protein in this area of the brain provides strong evidence that some of its cells have been damaged. However, obtaining this fluid requires a lumbar puncture, which not everyone is willing to perform. Therefore, those responsible for the report decided to study whether the levels of the protein in the blood could reflect neurological damage and thus avoid, with a simple clinical analysis, the much feared test.
They chose a group of families with genetic variants and different age groups, since a father with such a mutation has a 50% chance of transmitting his genetic error to his son and any child who inherits it has the same probability of developing dementia at the same time. same age as his parent. This period of time gives researchers the opportunity to study what happens in the brain in the years prior to the appearance of cognitive symptoms. Thus, they discovered that as the amount of protein increased, the size of the precuneus-part of the brain involved in memory-decreased.
"It is very difficult to predict a disease 16 years before it appears, but still you can see signs of alert at this stage," said Stephanie Schultz, co-author of the article. "This technique could be a good biomarker preclinical to identify it ". To find out if it met its objective, they collected data from 39 people who had not visited the specialist for more than two years. They underwent brain scans and two cognitive tests, which allowed them to confirm that those whose blood protein levels had increased were more likely to show signs of brain atrophy and a decrease in their abilities.
However, we must not lose sight of the fact that this increase in neurofilaments can also be caused by other types of conditions: people with multiple sclerosis during an outbreak or soccer players after a blow to the head. And, in addition, before this test can be used in patients with Alzheimer's or with some other neurogenerative disease, researchers must determine how much blood protein is considered "too high" and how fast it can increase before it becomes a cause for concern. "All this would allow us to identify brain damage," Gordon concludes. "What we can not guarantee yet is that someone, in five years, will develop some dementia. We keep working for that. "