Background: Periodontitis is a common, often undiagnosed, chronic infection of the supporting tissues of the teeth, epidemiologically associated with cardiovascular diseases. Since C-reactive protein (CRP) and other systemic markers of inflammation have been identified as risk factors for cardiovascular diseases, we investigated whether these factors were elevated in periodontitis.
Methods: Consecutive adult patients with periodontitis (localized n = 53; generalized n = 54), and healthy controls (n = 43), all without any other medical disorder, were recruited and peripheral blood samples were taken.
Results: Patients with generalized periodontitis and localized periodontitis had higher median CRP levels than controls (1.45 and 1.30 versus 0.90 mg/L, respectively, P = 0.030); 52% of generalized periodontitis patients and 36% of the localized periodontitis patients were sero-positive for interleukin-6 (IL-6), compared to 26% of controls (P= 0.008). Plasma IL-6 levels were higher in periodontitis patients than in controls (P = 0.015). Leukocytes were also elevated in generalized periodontitis (7.0 x 10(9)/L) compared to localized periodontitis and controls (6.0 and 5.8 x 10(9)/L, respectively, P= 0.002); this finding was primarily explained by higher numbers of neutrophils in periodontitis (P= 0.001). IL-6 and CRP correlated with each other, and both CRP and IL-6 levels correlated with neutrophils. The current findings for periodontitis were controlled for other known factors associated with cardiovascular diseases, including age, education, body mass index, smoking, hypertension, cholesterol, and sero-positivity for CMV, Chlamydia pneumoniae, and Helicobacter pylori.
Conclusions: Periodontitis results in higher systemic levels of CRP, IL-6, and neutrophils. These elevated inflammatory factors may increase inflammatory activity in atherosclerotic lesions, potentially increasing the risk for cardiac or cerebrovascular events.