Hi, Lynne! The following information is from The Sun paper (Baltimore) October 11, 2007.
"People who are purposeful, self disciplined and scrupulous about doing what they think is right -- in other words, are conscientious -- appear less likely to suffer from Alzheimer's disease.
Researchers performed neurological, cognitive and medical tests on about 1,000 healthy Catholic clergy, who apparently are no more or less conscientious than the rest of us. Volunteers rated themselves by responding to such items as, "I am a productive person who always gets the job done." After 12 years, 176 had developed Alzheimer's disease. Those who had the highest ratings of conscientiousness had an 89 percent lower risk of showing symtoms of the disease than those with the lowest scores.
Though the trait may have protected participants from the consequences, it didn't protect them from the disease process itself. Autopsies were done on the 324 people who died during the study period, and conscientiousness was not linked to a lower risk of the defining signs of the disease, brain plaques and tangles.
The study was published in this month's issue of the Archives of General Psychiatry."
The (Baltimore) Sun October 11, 2007
So the conscientiousness trait DOES protect people from the consequences, but it doesn't protect them from the defining signs of the disease and brain plaques of the their brain as seen by autopsy. Their brains might have signs of alzheimers but their thinking ability and their conscientiousness keeps them from showing symptoms.
Pretty interesting, huh? So our attitudes and daily behavior (our conscientiousness) can actually help us avoid alzheimers.