Double Good

Double Good

If you wanted to conduct a study to examine a possible link between periodontal disease and increased risk of Alzheimer’s disease, how could you design your research to match good dental hygiene to cognitive function?

One team of researchers came up with a novel solution: Twins!

Twins not in tandem

Last month, researchers gathered in Washington, D.C., for the first Alzheimer’s Association International Conference on Prevention of Dementia. One of the most intriguing presentations came from a University of Southern California (USC) team, in conjunction with researchers from Sweden’s Karolinska Institute.

Scientists know that Alzheimer’s may be passed along though genetics. Studies have shown that when one twin has AD, the chance that the other twin will develop the disease is quite high: around 60 percent. In the USC study, researchers examined data for 10,000 sets of twins enrolled in the Swedish Twin Registry. About 40 years ago, participants in the registry completed questionnaires that included detailed dental data. The questionnaire information was examined along with follow up medical records.

The USC team found 109 instances where one twin was diagnosed with dementia and the other wasn’t. Those with Alzheimer’s were four times more likely to have developed periodontal disease in middle age compared to their twins.

Margaret Gatz – the lead author of the study and a psychology professor at USC – told Medical News Today that the study doesn’t translate into the simplistic advice that flossing may prevent Alzheimer’s. Rather, the results indicate that an “inflammatory burden” on the body may play a significant role in triggering the genetic inclination to develop Alzheimer’s.

Other dementia risk factors were examined in this study, including level of education, stroke, participation in mentally stimulating activities and exercise in midlife. Twins with less education and twins who had experienced a stroke were at higher risk of developing Alzheimer’s. Inflammation has previously been shown to raise stroke risk.

The sunlight connection

Brushing and flossing teeth daily will help prevent gum disease. And while this regimen may not actually prevent Alzheimer’s, it does address inflammation. But there’s something else you can do to help keep inflammation at bay.

In the e-Alert “Take The D Train” (9/15/04), I told you about a Tufts University study in which blood tests and dental data on more than 11,000 subjects were examined. Researchers were looking for blood serum concentrations of vitamin D and the incidence of periodontal attachment loss. Results showed a significant association between low levels of vitamin D and an elevated risk of tooth loss due to periodontal disease.

These results are confirmed by two studies cited by John Jacob Cannell, M.D., in an article that appears on Dr. Joseph Mercola’s web site. Dr. Cannell featured a study from Belgium in which low doses of vitamin D supplements lowered the levels of two inflammatory markers (including C-reactive protein) in critically ill patients. In the second study, British researchers demonstrated an association between inflammation and vitamin D deficiency in more than 170 healthy adults.

In the e-Alert “No Shrinking Violet” (6/14/05), I told you how a moderate amount of sun exposure each day prompts your body to produce vitamin D. This is the best source of the vitamin, but it’s also available from food sources such as salmon and sardines, or cod liver oil, which provides more than 1,300 IU of vitamin D per tablespoon.

If you’ve been diagnosed with periodontal disease, or if you’re currently undergoing treatment for it, share this information about vitamin D with all of your healthcare providers: physician, dentist and periodontist.

Sources:
“Potentially Modifiable Risk Factors for Dementia: Evidence from Identical Twins” Alzheimer’s Association International Conference on Prevention of Dementia, Washington, D.C., 6/19/05, abstractsonline.com
“Gum Disease and Inflammation Linked to Dementia, Alzheimer’s Disease” Jennifer Warner, WebMD Magazine, 6/20/05, my.webmd.com
“Early Exposure to Inflammatory Disease Multiplies Alzheimer’s Risk, Say Researchers” Medical News Today, 6/20/05, medicalnewstoday.com
“Vitamin D Lowers Inflammation” John Jacob Cannell, M.D., 2/28/04, mercola.com