VANCOUVER, British Columbia -- Oral biologists from the
University at Buffalo School of Dental Medicine, among the first
researchers to report a relationship between gum disease and risk
of heart attack, now have identified the specific types of bacteria
that are most damaging to the cardiovascular system.
If the findings are confirmed, it may be possible to target the
bacteria with antibiotics or vaccines and lower the risk of heart
attack in persons with periodontal disease, according to Robert J.
Genco, D.D.S., Ph.D., chief investigator on this and earlier
studies on the connection between oral bacteria and heart
The findings are consistent with the hypothesis that specific
periodontal pathogens are implicated in the development of
cardiovascular disease, added Genco, SUNY Distinguished Professor
and chair of the UB Department of Oral Biology.
Results of the research will be presented by Genco here tomorrow
(March 13, 1999) at the combined meeting of the American
Association of Dental Research and the International Association of
Oral bacteria enter the bloodstream via small ulcers that
develop in the gum tissue of persons with periodontal disease. They
are thought to increase the risk of heart attack by: 1)
contributing to plaque formation, which narrows blood vessels and
increases the chance of clots forming, 2) accumulating around
damaged tissue, such as a lesion in the blood vessel or a replaced
heart valve, which also can narrow blood vessels and cause clots,
and 3) inducing platelets to aggregate, which increases the chances
of clots forming.
"We've known for some time that oral bacteria can precipitate
these kinds of reactions," Genco said. "We now know that these
reactions help explain how bacteria that cause gum disease can also
increase the risk for heart disease."
Seeking to identify the specific oral bacteria that are most
responsible for contributing to heart problems, Genco headed a
case-control study of 97 heart-attack patients and 233 controls,
who were tested for the presence of eight types of oral
Results showed that the heart-attack patients were heavily
infected with all bacteria types, but that the risk of heart attack
was related significantly only to three types: B. forsythus, P.
gingivalis and C. recta., organsims thought to cause periodontal
disease in adults. (Not all oral bacteria cause periodontal
Depending on the bacterial concentration, the increased risk of
heart attack in persons with one or another of these bacteria
ranged from 200-300 percent, compared to people with no evidence of
the bacteria, Genco said.
In a separate but related study, UB dental researchers analyzed
records of a random sample of 225 men treated as outpatients at the
Veteran's Affairs Medical Center in Buffalo, N.Y., to assess the
association between their dental and cardiovascular health. Dental
records were compared with diagnoses of coronary-artery disease,
congestive heart failure, angina, atrial fibrillation, myocardial
infarction or mitral-valve prolapse in both groups.
Results showed that patients with moderate or advanced
periodontal disease had a greater prevalence of cardiovascular
disease than patients with no periodontal disease, gingivitis or
early periodontitis. The study adds more evidence for a connection
between oral health and systemic disease.
The periodontal bacteria study was supported by grants from the
U.S. Public Health Service. Additional UB researchers were Tiejian
Wu, Ph.D.; Karen Faulkner, Ph.D., and Maurizio Trevisan, M.D., from
the Department of Social and Preventive Medicine, School of
Medicine and Biomedical Sciences; and Sara Grossi, D.D.S., and
Joseph J. Zambon, D.D.S., Ph.D., from the Department of Oral
Biology, School of Dental Medicine.
The outpatient study was conducted by Guy DiTursi, D.D.S., UB
clinical instructor of oral diagnostic sciences; James Katancik,
D.D.S., former UB graduate student, and Sebastian Ciancio, D.D.S.,
professor and chair of the UB Department of Periodontology.