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Vol. LXV, No. 1
January 4, 2013

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Quality Oral Health Care May Inhibit Dementia

It’s time to ’fess up. Do you brush your teeth after every meal? Floss regularly? See your dentist at least twice a year? If so, you may not only be warding off dental problems, you might also be reducing your risk of developing Alzheimer’s disease or other dementias, new study results indicate.

The study supporting a link between proper dental care and cognitive status was conducted by researchers in California and reported in a recent issue of the Journal of the American Geriatrics Society. Funding was provided by three NIH components: the National Cancer Institute, the National Institute on Aging and the National Institute of Arthritis and Musculoskeletal and Skin Diseases.

Brain experts have long sought clues to what risk factors may heighten the likelihood of developing Alzheimer’s disease and dementias associated with aging. However, aside from genetic factors and increasing age, few identifiable risk factors have been established to date (though a recent study indicates that loneliness in later life may elevate dementia risk). Alzheimer’s disease, a disorder of the brain that causes progressive cognitive decline, currently affects as many as 5 million Americans. There is no cure. It is the sixth leading cause of death in the U.S.

As for dental disease, the condition has already been associated with heart disease, stroke, diabetes, Crohn’s disease, ulcerative colitis and even a shortened lifespan.

Dr. Annlia Paganini-Hill

Dr. Annlia Paganini-Hill

Led by Dr. Annlia Paganini-Hill of the Clinic for Aging Research and Education of the University of California, Irvine, the scientists used mailed questionnaires to assess the association between tooth count/oral health behaviors and the development of dementia in nearly 5,500 elderly men and women who were followed for 18 years. The researchers adjusted for other factors that could have had an impact on the development of dementia such as smoking, alcohol consumption, head injury, education and family history of dementia. Results were based solely on self-reported dental habits and follow-up diagnoses of participants reported by relatives, hospital records and death certificates. (Subjects were not examined by dentists or the investigators).

“The major findings were that good oral health behaviors, as well as adequate natural masticatory function—that is, having enough teeth to chew food successfully—were associated with lower risk of dementia,” said Paganini-Hill. “Individuals with inadequate masticatory function [fewer than 10 teeth in the upper jaw and 6 in the lower jaw] who did not wear dentures had an elevated risk for dementia compared to those with an adequate number of teeth,” she said.

Paganini-Hill noted that, for men, the increase in dementia was 91 percent; for women, the increase was 22 percent. Equally important, “women who did not brush daily had a 65 percent increased risk for dementia compared to those brushing three times a day. In men, the increase was 22 percent,” she added.

While these findings are statistically significant, as well as provocative, the scientists are quick to note that their investigation does not indicate that poor dentition causes Alzheimer’s disease or severe cognitive decline, per se. However, an association between the two is apparent.

What can be gleaned from these results? “Periodontal pathogens [bacteria] can produce chronic system inflammation, including in the brain, and that could be the contributing factor to the association between dental disease and Alzheimer’s,” Paganini-Hill explained.

Your best protection, based on this research? Brush and floss every day and see your dentist for regular cleanings and oral exams, the researcher advised.

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