Periodontitis and incident type 2 diabetes: a prospective cohort study.

OBJECTIVES: The aim of this study was to investigate periodontitis as a risk factor for incident type 2 diabetes mellitus (T2DM) in a group of men aged 58-72 years. METHODS: One thousand three hundred and thirty-one dentate, diabetes-free men in Northern Ireland underwent a detailed periodontal examination during 2001-2003. Follow-up was by bi-annual questionnaire and for those reporting diabetes their general medical practitioner was contacted to validate diabetes type, treatment and diagnosis date. Cox's proportional hazard models were used to estimate the effect of periodontitis on incident diabetes. Multivariable analysis included adjustment for various known confounders. RESULTS: The mean age of the men was 63.7 (SD 3.0) years. There were 80 cases (6.0%) of incident T2DM. Follow-up was for a median period of 7.8 years (IQR 6.7-8.3). After adjusting for confounding variables, the hazard ratio (HR) for incident T2DM in men with moderate/severe periodontitis versus those with no/mild periodontitis was 1.69 (95% CI 1.06-2.69), p = 0.03. CONCLUSION: There was evidence in this homogenous group of dentate men, that those with moderate to severe periodontitis had a significantly increased risk of incident T2DM.