Link between cardiovascular disease and periodontal bacteria

Researchers report this week that older adults who have higher proportions of four periodontal-disease-causing bacteria inhabiting their mouths also tend to have thicker carotid arteries, a strong predictor of stroke and heart attack.

An investigative team of researchers from the University of Minnesota (Minneapolis) and Columbia University (New York City) presented their findings today at the 83rd General Session of the International Association for Dental Research, convening at the Baltimore Convention Center. As first reported in the journal Circulation, this is the first report of a direct association between cardiovascular disease and bacteria involved in periodontal disease, inflammation of the gums that affects an estimated 200 million Americans to various degrees.

The researchers collected an average of seven dental plaque samples from 657 subjects (60% female; 56% Hispanic, 23% African-American, 18% Caucasian, 3% Other; average age 69 years). They will re-examine the same group in less than three years, to evaluate the progression of atherosclerosis (heart disease). They measured both diseased and healthy sites for the presence of 11 oral bacteria--four widely regarded to be involved in causing periodontal disease, and the other seven serving as controls. Then, for evaluation of their cardiovascular health, the participants received a carotid intima-media thickness (IMT) measurement and provided a blood sample to determine their C-reactive protein levels. C-reactive protein has been reported to be elevated in people with periodontal disease, and recent studies found that testing for this protein may be predictive of developing heart disease.

The scientists found that the higher the levels of the periodontal-disease-causing bacteria, the more likely people were to have thicker carotid arteries.