Periodontal disease associated with blood glucose levels in urban Koreans aged 50 years and older: the Dong-gu study.

OBJECTIVE: To investigate the association of periodontal disease and the number of teeth present with the risk of prediabetes and diabetes as well as with blood glucose and HbA1c levels in adult Koreans. BACKGROUND: The relationship between periodontal disease and diabetes has not been fully elucidated. MATERIALS AND METHODS: Cross-sectional data from 5535 participants aged >/=50 years were obtained from 2008 to 2010. Periodontal status was measured as pocket depth (PD), clinical attachment loss (CAL) and bleeding on probing (BOP) recorded. The percentage of sites with a PD >/=4 mm, CAL >/=4 mm (CAL4) and BOP (BOP%) were recorded. Participants were divided into three groups according to PD4, CAL4 and BOP% measurements. Number of teeth present was divided into four groups. Participants were classified as normoglycaemic, prediabetic or diabetic based on HbA1c and fasting glucose levels. RESULTS: After full adjustment, the highest tertile of CAL4 (OR: 1.47, 95% CI: 1.18-2.02, p < 0.001), PD4 (OR: 1.58, 95% CI: 1.26-1.97, p < 0.001) and BOP% (OR: 1.37, 95% CI: 1.07-1.75, p = 0.012) had significantly increased odds of diabetes. The number of teeth present was inversely related to diabetes (p < 0.001) and prediabetes (p = 0.032) risk. Periodontal disease severity was positively associated with HbA1c and glucose levels. The number of teeth present was positively associated with HbA1c, but not glucose, levels. CONCLUSION: Periodontal disease and the number of teeth present are associated with an increased risk of diabetes and increased blood glucose and HbA1c levels in Koreans aged >/=50 years.