Objectives: Porphyromonas gingivalis has been associated with both periodontitis and cardiovascular disease. Filamentous components on P. gingivalis cell surfaces (fimA) play an important role in the colonization and invasion of host cells. In this study, P.gingivalis fimA genotypic distribution was analysed in dental plaque specimens from high and low cardiovascular (CV) risk patients in an Australian population.
Methods: Patients were retrospectively selected from an existing longitudinal study. A total of 90 patients with P.gingivalis positive plaque samples were selected according to CV-risk (≥6 classical risk factors=high CV-risk, n=48; ≤1 classical risk factor=low CV-risk, n=42) and periodontal status (≥6 sites with ≥4mm periodontal probing depth (PPD)=periodontitis, n=42; ≤1 site with ≥4mm PPD=periodontal health, n=48). The plaque specimens were analysed to discriminate the fimA genotype using conventional polymerase chain reaction with fimA type-specific primer sets.
Results: The distribution of fimA genotypes was similar in periodontally healthy individuals irrespective of their CV-risk group. In contrast, the prevalence of the type II, type IV and type 1b virulent fimA genotypes was greater in periodontitis patients with high CV-risk than in periodontitis patients with low CV-risk. The virulent type II fimA genotype had the highest prevalence in high CV-risk periodontitis patients (40%) and was 8 times greater than in low CV-risk periodontitis patients. The non-virulent type III fimA genotype was most prevalent in low CV-risk periodontitis patients (27%).
Conclusions: The results of this study indicate that virulent fimA genotypes occurred more frequently in patients with an increased risk of developing CVD, suggesting that the presence of specific fimA genotypes in dental plaque is associated with an increased risk of developing CVD.
Acknowledgements: This study was supported by unrestricted grants from National Health and Medical Research Council, HCF Health and Medical Research Foundation, Australian Dental Research Foundation and Queensland Health.