Alzheimer’s and rapid loss of smell have a new correlation that has been discovered by experts at the University of Chicago. Shutterstock photo illustration.
The diminished sense of smell of a person over time can not only predict the loss of cognitive function, but also, its rapid decline, can predict the structural changes in brain regions that are important for cognitive function. Alzheimer’s disease and the dementia in general.
This is the main conclusion of an investigation conducted by University of Chicago Medicine which offers “another clue” to how rapid decline in smell is a “really good” indicator of what will eventually happen structurally in specific brain regions, summarizes Jayant M. Pinto, one of its authors.
Based on a follow-up study of 515 seniors, it was published in Alzheimer’s and dementia: the newspaper of the Alzheimer’s Association.
The new study followed 519 seniors for years.
The memory plays a fundamental role In the human ability to recognize smells and the scientific community has long known the relationship between the sense of smell and dementia, recalls a statement from the University of Chicago.
The plaques and tangles -of proteins- that characterize the tissue affected by Alzheimer’s usually appear in the olfactory areas of the brain and those associated with memory before developing in other parts of this organ. However, it is not yet known whether this damage is the cause of a person’s decreased sense of smell.
Pinto and his team wanted to see whether it was possible to identify alterations in the brain correlated with a person’s loss of smell and cognitive function over time.
Alzheimer’s reduces the volume of gray matter in different areas of the brain.
“Our idea was that people with a rapidly diminishing sense of smell over time they would be in worse shape – and he would be more likely to have brain problems and even Alzheimer’s himself – than those in which he has slowly decreased or maintained a normal sense of smell, “details. Rachele Pacina.
The team used anonymous patient data from Rush University’s Memory and Aging project, started in 1997 to investigate the chronic conditions of aging and neurodegenerative diseases, like Alzheimer’s.
Patients undergo annual tests to check their ability to identify certain odors, their cognitive function or signs of dementia; some even had a magnetic resonance.
In their observations, the scientists found that a rapid decline in a person’s sense of smell during a period of normal cognition predicts multiple features of Alzheimer’s disease, including a decrease in the volume of gray matter in areas of the brain related to smell and memory, poorer cognition and an increased risk of dementia.
In fact, the risk of losing the sense of smell was similar to that of being carriers of the APOE-e4 gene, a known risk factor for genetic risk for the development of Alzheimer’s.
The changes were most noticeable in the primary olfactory regions, including the amygdala and the entorhinal cortexwhich is an important input for the hippocampus, a critical site in Alzheimer’s.
“We were able to show that the volume and shape of gray matter in the olfactory and memory-associated areas in people with a rapidly declining sense of smell were smaller than in those with a less severe olfactory declinePinto sums it up.
According to the researcher, this study “must be taken in the context of all known risk factors for Alzheimer’s,” including the effects of diet and exercise“.
“The sense of smell and its changes must be an important component in the context of a number of factors that we believe affect the brain in health and aging“.
For Pacyna, if it were possible to identify the people between 40, 50 and 60 years old At higher risk from the start, you may have enough information to enroll them in clinical trials and develop better drugs.
However, the scientists admit some limitations of the study, such as the fact that the participants only had an MRI, so there is a lack of data to specify when the tests began. structural changes in the brain or the speed at which brain regions shrunk. EFE
Source: Clarin