Scientists are searching for better ways to spot dementia before memory loss becomes obvious.
Dementia develops slowly over many years, and by the time symptoms appear, changes inside the brain have often been happening for a long time.
Finding people at higher risk earlier could allow doctors to recommend lifestyle changes, monitor brain health more closely, and prepare future treatments before major damage occurs.
A research team from the University of California, San Francisco and Beth Israel Deaconess Medical Center has developed a new artificial intelligence system that may help do exactly that.
Instead of relying on memory tests or brain scans, the system studies brain activity while people are asleep. The research was published in JAMA Network Open.
The scientists focused on electroencephalography, also called EEG, which records the brain’s electrical signals. EEG is painless and does not require surgery or injections.
During sleep, the brain produces many different electrical patterns, and researchers believe these patterns contain valuable information about brain health.
The new machine-learning model estimates a person’s brain age rather than simply looking at their actual birthday. A healthy brain may appear younger than a person’s real age, while a brain showing signs of faster aging may appear older. The difference between these two ages turned out to be an important clue.
The researchers trained their model using thirteen detailed features found in sleeping brain waves. They then tested it using information from about 7,000 adults aged 40 to 94 who had taken part in five different long-term studies. None of the participants had dementia at the beginning of the research, and they were followed for between three and a half and seventeen years.
During the follow-up period, about one thousand participants developed dementia. The researchers found that people whose estimated brain age was ten years older than their actual age had almost a forty percent greater chance of developing dementia. People whose brains appeared younger than expected had a lower risk.
Interestingly, traditional sleep measurements did not provide the same level of information. Measures such as total sleep time, time spent in different sleep stages, or how well people stayed asleep overnight were not as useful for predicting future dementia. The detailed electrical patterns inside the brain carried much richer information.
Some of these brain wave patterns are already known to support healthy thinking and memory. Delta waves are linked with deep, restorative sleep, while sleep spindles are believed to help the brain organize and store memories. Another feature called kurtosis, which measures large sudden spikes in brain activity, was linked to a lower risk of dementia.
The relationship remained strong even after researchers considered education, body weight, smoking, exercise, other illnesses, and inherited genetic risk. This suggests that the brain age score may capture important information that other health measures miss.
The researchers believe that future wearable sleep devices may one day collect these brain signals at home, making brain health monitoring easier and less expensive.
They also note that improving sleep quality, reducing sleep apnea through healthy weight management and exercise, and treating sleep disorders may help support healthier brain aging, although no single treatment can prevent dementia.
However, the research shows an association rather than proving cause and effect, and the AI system still needs further testing before becoming part of routine healthcare.
Even so, the findings suggest that sleep may provide one of the earliest windows into brain aging and could help identify people who would benefit from earlier prevention strategies.
If you care about brain health, please read studies about the likely cause of Alzheimer’s disease , and new non-drug treatment that could help prevent Alzheimer’s.
For more health information, please see recent studies about diet that may help prevent Alzheimer’s, and results showing some dementia cases could be prevented by changing these 12 things.
Source: University of California, San Francisco.
