Key periodontal pathogens in patients with coronary heart disease and incidence of new cardiovascular events

Aim of the study: In several studies periodontal disease has been revealed as an independent risk factor for coronary heart disease (CHD). The present study (ClinicalTrials.gov Identifier: NCT01045070) wanted to answer the question of whether periodontal marker bacteria are associated with the incidence of new cardiovascular events among patients with CHD. Material and Methods: 1002 in-patients with angiographically proven CHD (67.0 ± 10.9 years, 74% men) were included in the study. Four subgingival plaque samples per patient were pooled and analysed by PCR-SSO in a commercial laboratory (Hain Lifescience, Nehren) for the presence of DNA from A. actinomycetemcomitans, P. gingivalis, P. intermedia, T. forsythia, T. denticola, P. intermedia, P. micros, F. nucleatum, C. rectus, E. nodatum, E. corrodens, C. sputigena, C. gingivalis, and C. ochracea. A bacterium was then considered to be present if the number of genome equivalents was at the detection limit. After three years of follow-up, the incidence of the combined endpoint (CEP: myocardial infarction, stroke / TIA, cardiovascular death, death after stroke) was determined. The survival analyses were performed using Kaplan-Meier curves and log-rank tests (univariate) and with Cox regression (multivariate). Results: Follow-up data were received from 953 patients (drop out 4.9%). The incidence of CHD patients with CEP was 16.4%. Patients with CEP were rarely E. corrodens positive compared to patients without endpoint events (57.1% vs. 73, 3%, Log Rank test, p 0.0001). This result remained significant after adjustment for the cofactors age, gender, smoking, hypertension, dyslipidemia, diabetes, a history of CHD, positive CHD family history, severe periodontitis, bleeding index, and missing teeth (adjusted hazard ratio = 0.538, 95% CI 0,386- 0.749, p 0.0001). All other investigated bacteria as well as the number of detected bacterial species per patient were not associated with the cardiovascular outcome. Conclusion: The detection of E. corrodens was associated with a decreased risk for the occurrence of new cardiovascular events among patients with CHD. Keywords: coronary heart disease, periodontal bacteria, cardiovascular outcome