Carier Job, Education May Buffer Against Dementia

The participants' memory and cognitive skills were tested, and their brains were scanned to look for changes and damage. They were then followed for an average of 14 months, during which time 21 of those with mild cognitive impairment developed Alzheimer's disease.

Among people with the same level of memory impairment, those with more education and more mentally demanding jobs had significantly fewer brain changes and damage than those with less education and less mentally demanding occupations.

It included 242 people with Alzheimer's, 72 with mild cognitive impairment, and 144 with no memory problems. People with mild cognitive impairment have memory problems beyond what's normal for their age but not the serious memory problems associated with Alzheimer's disease.

This was true in both those with Alzheimer's and those with mild cognitive impairment who developed Alzheimer's, which suggests the cognitive reserve is already in effect during the mild cognitive impairment that precedes Alzheimer's.

"The theory is that education and demanding jobs create a buffer against the effects of dementia in the brain, or a cognitive reserve," study author Dr. Valentina Garibotto, of the San Raffaele University and Scientific Institute and the National Institute of Neuroscience in Milan, said in an American Academy of Neurology news release.

"Their brains are able to compensate for the damage and allow them to maintain functioning in spite of damage. There are two possible explanations. The brain could be made stronger through education and occupational challenges. Or, genetic factors that enabled people to achieve higher education and occupational achievement might determine the amount of brain reserve. It isn't possible to determine which accounts for our findings," Garibotto said.

The study was published in the Oct. 21 issue of Neurology.

-- Robert Preidt