A Cohort Study on the Association Between Periodontal Disease and the Development of Metabolic Syndrome

BACKGROUND: An association between periodontal disease and metabolic syndrome based on cross-sectional and case-control studies was recently reported, but their causal relationship has not been fully clarified. The objective of this cohort study is to investigate the association between periodontal disease and changes in metabolic-syndrome components to accumulate evidence of the causal relationship between the two conditions. METHODS: The study subjects consisted of 1,023 adult employees (727 males and 296 females; mean age: 37.3 years) who underwent medical and dental checkups between 2002 and 2006 and in whom all metabolic-syndrome components were within the standard values in 2002. The association between the presence of periodontal pockets and the positive conversion of metabolic-syndrome components was investigated using multiple logistic-regression analysis, odds ratios (ORs), and 95% confidence intervals (CIs). RESULTS: The presence of periodontal pockets was associated with a positive conversion of one or more metabolic components during the 4-year observation period (OR: 1.6; 95% CI: 1.1 to 2.2). The ORs for a positive conversion of one component and two or more components were 1.4 (95% CI: 1.0 to 2.1) and 2.2 (95% CI: 1.1 to 4.1), respectively, and the difference was significant for two or more positive components. Of the metabolic-syndrome components, positive conversions of blood pressure and the blood-lipid index were significantly associated with the presence of periodontal pockets. CONCLUSION: The presence of periodontal pockets was associated with a positive conversion of metabolic-syndrome components, suggesting that preventing periodontal disease may prevent metabolic syndrome.