A new study published in The Lancet Neurology shows that people who currently have no signs of memory problems may still face a higher risk of developing cognitive decline or dementia in the future—especially if they have higher levels of a brain protein called amyloid.
Researchers from the Mayo Clinic, led by Dr. Clifford R. Jack Jr., studied over 5,000 adults who were 50 years or older and had no signs of memory loss when the study began.
The team wanted to know if they could predict who might develop memory problems later by looking at amyloid levels in the brain. They used a special brain scan called a PET scan to measure these amyloid levels.
Amyloid is a protein that can build up in the brain and is often linked to Alzheimer’s disease. The amount of amyloid found in a PET scan is measured using a unit called “centiloids.”
The researchers found that the higher the centiloid value, the greater the person’s risk of developing mild cognitive impairment (MCI) or dementia over the next 10 years or even across their lifetime.
The study followed 5,158 people who had no cognitive problems and another 700 who already had mild memory issues. Results showed a clear pattern: as centiloid levels increased, so did the risk for developing memory problems. This trend was especially strong in people who carry a gene called APOE ε4, which is already known to raise the risk for Alzheimer’s.
For example, among men with the APOE ε4 gene who were 75 years old and had no current memory issues, the lifetime risk of developing MCI rose from 56.2% at a centiloid value of 5 to 76.5% at a centiloid value of 100. The risk was even higher for women with the same gene, rising from 68.9% to 83.8% across the same centiloid range.
These results suggest that measuring amyloid levels with PET scans could help doctors estimate how likely someone is to develop memory problems in the future—even before they show symptoms.
Co-author Dr. Ronald C. Peterson explained that this type of risk estimate could guide people in deciding when to start treatments or make lifestyle changes, such as improving their diet, exercising more, or managing health conditions like diabetes and high blood pressure.
It’s important to note that some of the study’s authors have connections to drug companies that make treatments for Alzheimer’s disease. However, the study provides useful information about how brain scans might one day be used to predict and possibly delay the start of memory loss.
In summary, people who seem mentally healthy now might still have a high risk of developing memory issues if their brain has a lot of amyloid buildup. Knowing this early could help individuals take steps to protect their brain health in the future.
If you care about dementia, please read studies that eating apples and tea could keep dementia at bay, and Olive oil: a daily dose for better brain health.
For more health information, please see recent studies what you eat together may affect your dementia risk, and time-restricted eating: a simple way to fight aging and cancer.
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