Dementia: study shows sign that can predict risk up to ten years earlier

A new study has discovered a sign that could indicate risk of dementia five to ten years before symptoms appear – which include memory loss, problems with speaking and writing and difficulty understanding information. According to researchers, the narrowing of a band of brain tissue called cortical gray matter becomes thinner in people who develop cognitive decline.

You results were published in Alzheimer's & Dementia: The Journal of the Alzheimer's Association. In the study, researchers at the University of Texas Health Science Center in the United States analyzed more than a thousand participants in a study called Framingham Heart Study and 500 more volunteers from California. In total, participants were, on average, 70 and 74 years old. They all underwent an MRI scan of their brains.

The study compared people with and without dementia at the time of the MRI. Exams carried out 10 years earlier were also analyzed to compare the results.

“We went back and looked at brain MRIs taken ten years earlier and then mixed them together to see if we could discern a pattern that reliably distinguished those who later developed dementia from those who didn’t,” co-author Sudha Seshadri said. of the study and senior investigator at the Framingham Heart Studyin a statement.

The results showed that thinner bands of the brain's cortical gray matter were related to cognitive decline and the development of dementia, while thicker bands of the same region had better results on MRI scans.

“Although more studies are needed to validate this biomarker, we are off to a good start,” said Claudia Satizabal, lead author of the study. “The relationship between thinning and risk of dementia behaved similarly across different races and ethnic groups,” she adds.

Discovery could help with early diagnosis and new studies

In the view of the study authors, the findings could help to identify people at high risk of developing dementia early.

“By detecting the disease early, we have a better window of time for therapeutic interventions and lifestyle modifications, and to better monitor brain health to slow individuals' progression to dementia,” comments Satizabal.

Furthermore, the results may help minimize costs in future clinical trials, as it may be possible to select participants who have not yet developed dementia – but who are at risk via the gray matter thinning biomarker – for these studies. For example, they may participate in studies for experimental dementia drugs.

The next step, according to the study authors, is to identify which risk factors may be associated with thinning of the cortical gray matter. For Satizabal, these factors may include diet, exposure to environmental pollutants, cardiovascular risk and genetics.

“We looked at APOE4, which is the main genetic factor related to dementia, and it was not in any way related to gray matter thickness,” Satizabal said. “We think this is a good thing, because if thickness is not genetically determined, then there are modifiable factors, such as diet and exercise, that can influence it,” he concludes.