Alzheimer's Disease – Nun Study
It is estimated by 2050 there will be more than 14 million Americans who will suffer from Alzheimer's. While it is commonly associated with old age, there is a growing number of people in their 40s who are being diagnosed with Alzheimer's Disease. For over 20 years a longitudinal study has been underway to find the causes of this dreadful disease.
In 1986, Dr. David Snowdon, University of Minnesota began his work with a group of nuns called the School Sisters of Notre Dame. It is a landmark study, which continues to this day. What makes this study so extraordinary, is that 678 nuns have agreed to volunteer their brains upon their deaths. Since Alzheimer's can only be accurately diagnosed through autopsy, their generosity has helped researchers to have a better understanding of AD.
One of the factors that makes these nuns such ideal candidates, is their homogeneity. Most of them had been together for seventy years or so and had the same diet and life-style and so forth.
Researchers from different disciplines (psychology, neurology, pediatrics, and the School of Public Health) have access to this growing body of information, as well.
Most nuns were in their 80's to 100's, but had entered the convent at the age of 22. Upon entering the convent the nuns were required to write essays introducing themselves. What Dr. Snowdon observed was that the moreense with ideas their writings were, the less likely the nuns were to have Alzheimer's. Again, the more sophisticated their grammar, the less likely they were to have Alzheimer's. On the other hand, the less complex the writings were, the more likely they were to have Alzheimer's.
Emotional states were also predictors for Alzheimer's. Again, the more depressed the tone, the more likely the nuns were to have AZ.
Wait, it gets even more interesting. In some cases, Dr. Snowdon discovered that there were nuns who had all the neuronal tangles and plaques of full-blown AD, yet had demonstrated none of the symptoms! One of the nuns, who was 101 when she died had been teaching the higher mathematics briefly up until she died.
In terms of the nuns' writings, what does it mean? Did the chicken come first, or was it the egg? Does idea density, or lack of them, determine if a person will get Alzheimer's? Or is it more simplistic way of writing an early manifestation of Alzheimer's?
One thing of note, is that nuns who were teachers (and who continued to teach), were less likely to experience AD, than those nuns who had been more service-oriented. Which seems like a case of use it or lose it.
Another interesting finding, dietary this time, was that nuns with high folate levels manifestly badly any Alzheimer's-type damage to their brain in their autopsies. This is explained as folate acts as a check against the amino acid, homocysteine, which has been implicated in cardiovascular disease. Higher levels of folate in the blood sees to offer protection against stroke – and may even protect brain cells from damage by homocysteine in the brain.
The Nun Study is continuing, and there are now a total of five chapters operating within the US