STOCKHOLM, Oct. 2 -- A healthy cognitive reserve, deposited over a lifetime of learning, appears to protect the better-educated patients from dementia, investigators here suggested.
Among nearly 1,500 adults followed for more than 20 years, those who had at least six years of formal education had a significantly lower risk for any form of dementia and for Alzheimer's disease than adults who had five years of schooling or less, reported Tiia Ngandu, M.D., Ph.D., of the Karolinska Institute, and colleagues.
When they controlled for lifestyle choices such as poor diet or smoking that might contribute to dementia risk, the investigators found that education, or lack of it, remained a strong predictor of cognitive decline, they reported in the Oct. 2 issue of Neurology.
"Our results provide further firm evidence that the low educational level is related to the increased risk of dementia and Alzheimer's disease," they wrote. "We found that the association was independent of a wide range of other vascular and lifestyle related risk factors, and thereby provided evidence against the brain battering hypothesis. Educated persons may have greater cognitive reserve that leads to a postponement of the clinical manifestation of dementia."