People with more bacteria
in their mouths also have more evidence of heart disease,
researchers said on Monday in a study strengthening
the evidence for a link between gum disease and heart
The study of 657 people
who had no history of stroke or heart attack showed
that people with more bacteria that cause periodontal
disease also had thicker carotid arteries -- a strong
indicator of clogged blood vessels.
Writing in the American
Heart Association's journal Circulation, the team at
Columbia University in New York said the association
held even when other heart risk factors were taken into
"This is the most direct
evidence yet that gum disease may lead to stroke or
cardiovascular disease," said Dr. Moise Desvarieux at
Columbia University Medical Center, who led the study.
"And because gum infections
are preventable and treatable, taking care of your oral
health could very well have a significant impact on
your cardiovascular health."
Researchers believe the
bacteria that cause the gum disease may spread into
the bloodstream and stimulate the immune system, causing
inflammation that results in the clogging of arteries.
Hardening of the arteries involves the inflammation
process, and other studies have strongly linked heart
disease with inflammation.
The researchers used
ultrasound to measure the thickness of the carotid artery,
which leads from the heart to the brain. They also made
sure that they were measuring only levels of bacteria
associated with both gum disease and heart disease.
These are Actinobacillus
actinomycetemcomitans, Porphyromonas gingivalis, Tannerella
forsythia, and Treponema denticola.
"Although more than 600
bacteria have been shown to colonize the mouth, each
person tends to carry different proportions of these
microbes," said Dr. Panos Papapanou, a periodontist
who worked on the study.
Now they need to show
which came first -- the bacteria or the heart disease.
"We will re-examine the
participants in less than three years, and, at that
point, we can better evaluate the progression of the
atherosclerosis and, hopefully, begin to establish a
time frame underlying the diseases," said Dr. Ralph
Sacco, who also worked on the study.