People who never learned to read and write may be at increased risk for dementia.
Researchers studied 983 adults 65 and older with four or fewer years of schooling. Ninety percent were immigrants from the Dominican Republic, where there were limited opportunities for schooling. Many had learned to read outside of school, but 237 could not read or write.
Over an average of three and a half years, the participants periodically took tests of memory, language and reasoning.
Illiterate men and women were 2.65 times as likely as the literate to have dementia at the start of the study, and twice as likely to have developed it by the end. Illiterate people, however, did not show a faster rate of decline in skills than those who could read and write.
The analysis, in Neurology, controlled for sex, hypertension, diabetes, heart disease and other dementia risk factors. “Early life exposures and early life social opportunities have an impact on later life,” said the senior author, Jennifer J. Manly, a professor of neuropsychology at Columbia. “That’s the underlying theme here. There’s a life course of exposures and engagements and opportunities that lead to a healthy brain later in life.”
“We would like to expand this research to other populations,” she added. “Our hypothesis is that this is relevant and consistent across populations of illiterate adults.”