January 15, 2020
People who never learned to read or write have nearly three times greater risk of developing dementia than people who can read and write, according to new research. The findings add to a growing body of evidence that reading, writing and other intellectual stimulation may help to bolster the brain and perhaps even help to protect it against Alzheimer’s disease and other forms of dementia in old age.
“Being able to read and write allows people to engage in more activities that use the brain, like reading newspapers and helping children and grandchildren with homework,” said study author Jennifer J. Manly of Columbia University Vagelos College of Physicians and Surgeons in New York. “Our new study provides more evidence that reading and writing may be important factors in helping maintain a healthy brain.”
“Our study also found that literacy was linked to higher scores on memory and thinking tests overall, not just reading and language scores,” Dr. Manly continued. “These results suggest that reading may help strengthen the brain in many ways that may help prevent or delay the onset of dementia.” The findings were published in Neurology, the medical journal of the American Academy of Neurology.
Earlier studies have identified having only a few years of schooling as a risk factor for Alzheimer’s disease. And activities like reading books, doing crossword puzzles speaking a second language or playing a musical instrument have been tied to a lower risk of dementia.
The current study looked at 983 men and women, average age 77, who lived in northern Manhattan. Many were born and raised in rural areas in the Dominican Republic where access to education was limited. Among this group, which had only a few years of schooling, 237 had never learned to read and write.
Participants had medical exams and underwent regular tests of memory and thinking skills, where they were asked, for example, to list as many items as possible under categories like “fruit” or “clothing,” or to recall a list of unrelated words.
After controlling for factors like age, socioeconomic status and cardiovascular disease, the researchers found that people who were illiterate had nearly a three times greater chance of having dementia at the start of the study. By the end of the study, four years later, those who couldn’t read or write were twice as likely to develop dementia than those who were able to read and write.
“Even if they only have a few years of education, people who learn to read and write may have lifelong advantages over people who never learn these skills,” Dr. Manley said.
The researchers say that reading provides an important means of acquiring and structuring new knowledge that benefits not just language ability, but reinforces skills in working memory, visual memory, spatial processing and motor skills. It is possible that cognitively stimulating activities like reading and writing at a young age may help the brain to build up a more robust network of connections, and that reading and writing later in life may help to maintain or bolster existing connections between brain cells and help to compensate for those lost in illnesses like Alzheimer’s disease.
By ALZinfo.org, The Alzheimer’s Information Site. Reviewed by Marc Flajolet, Ph.D., Fisher Center for Alzheimer’s Research Foundation at The Rockefeller University.
Source: Miguel Arce Renteria, PhD, Jet M.J. Vonk, PhD, Gloria Felix, BA, et al: “Illiteracy, dementia risk, and cognitive trajectories among older adults with low education.” Neurology November 13, 2019