Detection of Periodontopathic Bacterial DNA in Samples of Cardiovascular Plaque

Objectives: Infectious microorganisms have been suggested to play a role in the etiology and epidemiology of atherosclerosis and related cardiovascular disease. Some epidemiological studies have shown an association between periodontitis and cardiovascular disease, but others do not show. To clarify this relationship, we detected periodontopathic bacterial DNA in plaque samples of the coronary artery disease lesions and in periodontal diseased sites. Methods: Fifty-nine patients who were scheduled to undergo surgery for cardiovascular disease were enrolled after written informed consent was obtained. Forty-five of these patients were found to possess deep periodontal pockets with chronic periodontitis. Samples of atherosclerotic plaque were obtained from the coronary artery walls of the patients. Samples from the periodontal region were also obtained at least one week before the surgery. DNA was isolated from the tissue by conventional methods. The presence of periodontopathic bacterial DNA was detected by PCR. Standard precautions were undertaken to preclude spurious results due to contamination. Results: The detection rates of Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Bacteroides forsythus, Treponema dentocola and Campylobacter rectus from cardiovascular samples were 22.0%, 22.0%, 5.1%, 23.7%, and 15.3%, respectively. The presence of P. gingivalis and C. rectus in periodontal sites and cardiovascular diseased regions was positively correlated (p<0.05, chi-square test). Conclusion: Oral colonization by periodontopathic bacteria can lead to asymptomatic bacteremia and/or contamination of the bacterial endotoxin that in turn could affect cardiac pathology. Thus, asymptomatic bacteremia due to periodontopathic bacteria may be an etiologic factor in cardiovascular plaque accumulation.