Periodontal microbiota in patients with coronary artery disease measured by real-time polymerase chain reaction: A case-control study

Background: Recent data have shown that periodontal disease may increase the risk of occurrence of coronary heart disease in which inflammation initiated by bacteria and their compounds might be a common causal factor. This case-control study aimed at studying the relationship between periodontal disease and coronary artery disease (CAD) based on clinical and periodontal microbiologic parameters. Methods: A total of 90 male subjects, 48 to 80 years of age, were included in this study. Forty-five men had CAD (CAD+), which was confirmed by coronary angiography. Forty-five age-matched controls showed no history or symptoms of CAD (CAD-). All subjects underwent a clinical periodontal examination including assessment of tooth loss, probing depth, clinical attachment level, and bleeding on probing. In the CAD+ group, this examination took place 1 day before coronary angiography. Subgingival microbial samples were taken and evaluated by means of real-time polymerase chain reaction (RT-PCR) for the total amount of bacteria and the following periodontopathogens: Actinobacillus actinomycetemcomitans, Porphyromonas gingiualis, Preuotella intermedia, Paruimonas micra (formerly Micromonas micros), Dialister pneumosintes, and Campy lobacter rectus. Results: Compared to control subjects, CAD+ subjects had significantly deeper pockets (2.28 mm versus 2.96 mm; P < 0.001) and greater attachment loss (2.85 mm versus 3.65 mm; P < 0.001), and this difference remained statistically significant after adjusting for smoking. No significant differences were observed between cases and controls with regard to the number of teeth present. P. intermedia was the only periodontal pathogen that showed significantly higher mean counts in CAD+ subjects compared to CAD- subjects. Higher counts of total bacteria, P. micra, D. pneumosintes, and C. rectus were found in the CAD- group. Conclusion: The results suggest that a relationship between periodontal disease and coronary heart disease exists, although P. intermedia was the only periodontopathogen related to CAD.