Good genes and strong cognitive skills can help protect the brain from aging and prevent memory loss in older adults, according to a new study published by the American Academy of Neurology. Meanwhile, modifiable lifestyle factors including smoking and high blood pressure can accelerate brain aging.
The researchers set out to investigate how some people remain sharp into their 90s, even if they have the amyloid plaques in the brain that are associated with Alzheimer’s disease. Other people have been found to reach their 90s without ever developing plaques.
The study followed 100 older adults without dementia for 14 years, at which point the participants had an average of 92 years old. The volunteers were given thinking and memory assessments, as well as brain imaging scans to determine whether they had amyloid-beta plaques in their brains.
Study lead author Dr. Beth E. Snitz is a professor in the Department of Neurology at the University of Pittsburgh.
“With more and more people living into their 90s and even 100s, it’s increasingly important that we be able to understand and predict the factors that help people preserve their thinking skills as they age and determine if there are any changes people can make during their younger years that can improve their chances of cognitive resilience,” said Dr. Snitz.
The investigation revealed that participants who had normal scores on the thinking and memory tests at the start of the study were less likely to exhibit signs of brain aging, even if they had amyloid plaques.
“This finding is consistent with the theory that people with better lifelong thinking and memory skills have a ‘cognitive reserve’ that provides a buffer of protection against changes in the brain,” said Dr. Snitz. “They can better compensate for any underlying brain changes.”
The researchers also found that people with the gene variant apolipoprotein E ε2 (APOE ε2) were more resistant to developing amyloid plaques. This gene was previously associated with improved brain aging, including a decreased risk of Alzheimer’s disease.
The study showed that individuals with the APOE ε2 gene version were six times less likely to develop plaques than people without the gene. This gene variant is not extremely common, and only one out of ten study participants were found to have it.
The experts report that participants who never smoked were over 10 times more likely to maintain their thinking skills, even with plaques.
Furthermore, individuals who had higher scores on a blood pressure measure called pulse pressure tended to have a greater number of plaques over time. Pulse pressure increases with age and represents aging of the vascular system.
The study is published in the journal Neurology.
By Chrissy Sexton, Earth.com Staff Writer