Periodontal inflammation is associated with increased circulating levels of endothelial progenitor cells: a retrospective cohort study in a high vascular risk population.

BACKGROUND: One of the main biological mechanisms behind the link between periodontitis and atherosclerotic vascular diseases is vascular endothelial dysfunction. Particularly, circulating endothelial progenitor cells (EPCs) have been considered a biomarker of altered vascular endothelial function. OBJECTIVES: The aim of this study was to investigate relationship between periodontal inflammation and increased number of circulating EPCs. DESIGN: This is retrospective cohort study. METHODS: In this study, 85 elderly patients with a previous history of hypertension were followed up to 12 months. A baseline full-mouth periodontal assessment was carried out, and the amount of periodontal tissue inflamed per subject was calculated as a proxy of periodontal inflammation [periodontal inflamed surface area (PISA)]. The number of circulating EPCs (CD34(+)/CD133(+)/KDR(+)) was determined by flow cytometry from peripheral blood samples collected at baseline and 12 months. RESULTS: Mean concentrations of CD34(+)/CD133(+)/KDR(+) progenitor cells were higher in periodontitis patients than in those without periodontitis at baseline [55.4, 95% confidence interval (CI) = 20.8 to 90.0 versus 27.2, 95% CI = 13.6 to 40.8, p = 0.008] and 12 months (114.6, 95% CI = 53.5 to 175.7 versus 19.1, 95% CI = 10.8 to 27.4, p = 0.003). A significant increase over the follow-up was noticed in the group of subjects with periodontitis (p = 0.049) but not in the nonperiodontitis group (p = 0.819). PISA was independently associated with CD34(+)/CD133(+)/KDR(+) EPCs at baseline (B coefficient = 0.031, 95% CI = 0.005 to 0.058; p = 0.021). The relationship between PISA and CD34(+)/CD133(+)/KDR(+) EPCs at 12 months was confounded by increased baseline body mass index (B coefficient = 0.064, 95% CI = -0.005 to 0.132; p = 0.066). CONCLUSION: Periodontal inflammation is associated with high number of CD34(+)/CD133(+)/KDR(+) EPCs, thus supporting a potential link between periodontitis and endothelial dysfunction.