Study: Intellectual Acuity in Early Life Linked to Lower Rate of Alzheimer's

Intellectual acuity early in life appears to be linked to a lower incidence of Alzheimer's disease, according to researchers who have been studying a group of 687 nuns from the School Sisters of Notre Dame.

The nuns agreed 15 years ago to allow researchers to study them while alive and after their death in an effort to better understand longevity.

"We learned that by looking at early mental function, we could predict with 85 to 90 percent accuracy which ones would show brain damage typical with Alzheimer's 60 years later," said Dr. David Snowden, professor of neurology at the University of Kentucky and lead author of the study published in the Journal of Personality and Social Psychology.

Complicated writing, or prose with more ideas crammed into a sentence appeared to be linked with the development of Alzheimer's disease as well as head trauma or stroke, he said..

Researchers also found a lower incidence of Alzheimer's in nuns with higher levels of folic acid in their blood.

The findings also showed that a positive emotional outlook may help increase longevity.

From their writings, researchers were able to ascertain the level of positive or negative emotion in the nuns' personalities and determine how optimistic they were about their future. The researchers found an association between a positive attitude in early writings with living as much as 10 years longer.

"It's been known for years that pathological expressions of emotion like depression or hostility can lead to illness," said Snowden. "Our theory is that negative emotional states such as anxiety, hatred and anger can have a cumulative effect on the body over time. Over decades and decades, people that turn these negative emotions on and off several times daily are hurting themselves and are more likely to fall victim to heart disease and stroke."

The nuns were considered a good study group because they didn't smoke or drink and had similar lifestyles. The researchers were given access to the nuns' early writings of their autobiographies, gave the nuns periodic memory tests, blood tests, and performed autopsies on their brains after death.

Other sources: Journal of Personal and Social Psychology, AP