Researchers at the Hospital del Mar, in Barcelona, ??have identified a new marker that predicts the faster or slower evolution of Alzheimer’s disease and other dementias. This is the degree of deterioration of the blood-brain barrier, a value that is relatively easy to verify.
Alzheimer’s tends to progress slowly and patients’ condition gradually worsens over the years, but the speed of deterioration is different for each person. One of the reasons for the disparity in this evolution lies in the state of the blood-brain barrier. This system is a network of blood vessels and tissue made up of closely linked cells, which regulates exchanges between the blood and the brain in order to prevent harmful substances from entering the brain.
To check whether the state of this ‘filter’ acts as a predictor of the evolution of Alzheimer’s, researchers have followed more than 300 patients for four years. These are people diagnosed with mild cognitive impairment or dementia, caused by different neurodegenerative diseases. The diagnosis is based on data from a lumbar puncture, magnetic resonance imaging, and neuropsychological assessment.
The results indicate that in patients who were detected, through lumbar puncture, higher levels of albumin (a protein produced by the liver that is mainly found in the bloodstream and helps keep blood from leaking to other tissues). The evolution of the disease is more accelerated. The risk of rapid progression increases by 8% for every 10% increase in the level of albumin in the cerebrospinal fluid.
“The initial hypothesis of the research is that in recent years there is more and more evidence that cardiovascular risk factors are also risk factors for cognitive impairment,” researcher Albert Puig-Pijoan, associate of the neurology service, explains to La Vanguardia. from the Hospital del Mar. “In the blood-brain barrier, whose main function is to regulate the passage of substances between the blood and the brain and vice versa, an increase in permeability indicates a malfunction of this structure.”
The marker of the permeability level is the ratio between the concentration of albumin in the cerebrospinal fluid and the blood. And it is not difficult to measure. It is a test accessible to laboratories. “A lumbar puncture is enough, which today is a common practice in diagnosis, especially in the initial stages, and a blood test, performed simultaneously, which does not have any complications,” explains the doctor.
According to Puig-Pijoan, due to its simplicity the method can have an impact on clinical practice and would be valid for different causes of cognitive impairment. “On the other hand, it is inferred that cardiovascular health is of great importance both in the prevention and in the evolution of cognitive deterioration, and that therapies aimed at preserving or restoring the function of the blood-brain barrier could play a key role in the future” .
Led by the Hospital del Mar Research Institute, the research that has identified the new predictor of the progression of neurodegenerative diseases has been published in Alzheimer’s
According to Puig-Pijoan, the work will continue with more, larger and specific cohorts, in order to validate the marker for different pathologies and refine the variables that allow predicting the evolution of people diagnosed with some type of dementia.
