Education won't help much when it comes to dementia, study says
Posted February 6, 2019 4:06 p.m. EST
CNN — Don't rest on your laurels, as your scholastic achievements will not save you from dementia, new research suggests.
A high level of education does not delay the start of dementia and does not slow the speed of decline, according to a study published Wednesday in the journal Neurology. Rather, it might be best to remain inquisitive and intellectually active throughout your years, the lead researcher says.
True, it's been proved by previous research that less-educated people develop dementia at a higher rate than people who put more time into the books, explained Robert Wilson, lead author of the study and director of cognitive neurosciences at Rush Medical College in Chicago.
"Education has some benefit, but it's somewhat limited," Wilson said. "The real game is how much you're declining," and education fails to positively impact that.
Still, the activities that might help you in old age are the same ones learned at school, he said: "continuing to read or vigorously challenge yourself with other pursuits and intellectually challenging occupations."
Cognitive reserve: your brain's ability to improvise
Dementia is a behavioral state that gradually erodes thinking, memory, language, problem-solving and self-management skills.
"The main drivers of dementia are these neurodegenerative and cerebrovascular pathologies that accumulate in the brain and are age-related," Wilson explained. Brain pathologies include the protein plaques and tangles seen in Alzheimer's disease, as well as the infarcts (small areas of dead tissue) seen in cerebrovascular diseases.
Although studies have shown that about 50% of cognitive decline in old age is associated with brain pathologies, there's another 50% that isn't linked to them and so must be due to something else, Wilson said.
That "something else" is generally thought to be cognitive reserve, he said. That's a measure of the brain's resilience and ability to improvise and overcome obstacles, and it's known to protect cognitive function in old age. "The big challenge is: What contributes to cognitive reserve, and how does it work?"
The new study, then, is an attempt to explore how much education contributes to cognitive reserve. Wilson and his colleagues analyzed data gathered from older people in the Chicago metropolitan area who agreed to annual detailed tests and to donate their brains for autopsy after death.
On average, the 2,899 study participants had slightly more than 16 years of education. Wilson and his colleagues divided participants into three groups: those educated for 12 years or fewer, those educated 13 to 16 years and those educated 17 years or more. While 696 participants developed dementia during the study, 405 of the subgroup also died during the study period and were autopsied.
Looking at test scores and autopsy results, Wilson and his colleagues found a link between having a higher level of education and having higher thinking and memory skills at the start of the study.
All good, said Wilson, who noted that it's "important how healthy your brain is when you begin old age because it's likely that a lot of bad things are going to happen to your brain in old age, [since] these pathologies are very, very, very common."
Beyond that, though, more years spent in the classroom did not prove helpful. No correspondence was seen between education level and how old people were when dementia symptoms began or the speed of their cognitive decline. This was also seen in the autopsy results: High levels of Alzheimer's disease markers in the brain, and not education, determined the pace of decline.
A possible reason why education isn't having a big effect on cognitive reserve could be that "it's so remote," Wilson said. Current activities, not past, may be more likely to influence cognitive reserve.
Exactly which activities will fill the mental gas tank as we grow old?
"How cognitively active you are, what you read and things like that," Wilson said. "We've also found some personality traits: Conscientiousness is related to your cognitive functioning in old age. There's also an aspect of well-being called 'purpose in life,' which is sort of the ability to find meaning in everyday activities. People high in that trait are also able to maintain better cognitive functioning in old age despite accumulating pathology at the same rate as everyone else."
On the flip side, depression corresponds with negative cognitive changes in old age, he said.
New finding is 'surprising'
Dr. Dilip Jeste, a professor of psychiatry and neurosciences at the University of California, San Diego, said the study's "new and surprising finding" is that "education seemed to contribute little to cognitive reserve, in contrast to the long-held belief that it is a major contributor."
Jeste, who was not involved in the new research, wrote in an email that the study's strengths included a large number of participants and comprehensive testing. However, participants were "mostly non-Latino Whites, so the results may not apply to ethnic minorities, especially those with lower levels of education," he wrote.
Research now suggests that late-life cognitive activity and mid-life physical activity may predict the rate of cognitive change, Jeste said. So, all things being equal, older people who stay mentally active may experience less decline than those who do not.
Emory University's Dr. Aliza P. Wingo, a psychiatrist and an assistant professor of psychiatry and behavioral sciences, and Dr. Thomas S. Wingo, a neurologist and an assistant professor of neurology and human genetics, described the study as "thorough" while noting that the findings "may not be easy to generalize beyond the people they studied given the relatively old age of participants and many years of educational attainment most of these participants had."
Neither participated in the new research, though their own work examines how psychological factors influence dementia risk.
"We do this by looking at genetic material and proteins from the brains of research volunteers and relating changes in the brain to their cognition in life or brain pathologies at death," they wrote in an email. "What is interesting is that purpose in life and depression influence dementia risk independent of education, age, or other known risk factors." Their hope is to identify new factors that protect against mental decline.
The best advice for anyone worried about developing dementia, Jeste said, "is to follow [a] healthy lifestyle, with physical exercise (especially aerobic), cognitively stimulating activities, social engagement, healthy diet rich in antioxidants (green leafy vegetables, vitamin E, legumes, nuts), sleep hygiene, meditation for relaxation, and positive attitude.
"The mantra is: It is never too late nor too early in life to start practicing [a] healthy lifestyle."