Objective: In periodontitis, overgrowth of gram-negative bacteria may cause endotoxemia and systemic inflammation leading to cardiovascular diseases (CVD). We investigated in a prospective study the associations of serum endotoxin, antibodies to periodontal pathogens, and inflammation markers with the risk of incident CVD.
Methods and results: The FINRISK 1992 cohort of 6051 individuals was followed up for 10 years. We examined 185 incident CVD events and a control cohort of 320 individuals using a prospective case-cohort design. High antibody response to periodontal pathogens independently predicted incident CVD events with hazard ratios (HR, quartile 4 versus quartiles 1 to 3, 95% CI) of 1.87 (1.13 to 3.08). The subjects with a high antibody response and high CRP or interleukin (IL)-6 had multivariate-adjusted HRs of 3.01 (1.27 to 7.09) and 3.11 (1.42 to 6.83) compared with low-responders, respectively. The corresponding HRs for high endotoxin concentration were 1.82 (1.22 to 2.73, alone), 3.92 (1.99 to 7.74, with CRP), 3.54 (1.78 to 7.03, with IL-6), and 2.26 (1.13 to 4.52, with tumor necrosis factor (TNF)-alpha) after adjusting for age and gender. These associations were abolished after adjusting for serum lipids. High endotoxin/HDL ratio, however, had a multivariate-adjusted HR of 1.92 (1.19 to 3.08) for CVD events.
Conclusions: Our results suggest that the exposure to periodontal pathogens or endotoxin induces systemic inflammation leading to increased risk for CVD.