Association between blood lead and mercury levels and periodontitis in the Korean general population: analysis of the 2008-2009 Korean National Health and Nutrition Examination Survey data

We present data from the Korean National Health and Nutrition Examination Survey 2008-2009 regarding the association between blood lead and mercury levels and periodontitis in a representative sample of the adult South Korean population. The analysis was restricted to participants a parts per thousand yen20 years of age who completed the health examination survey, including blood lead, cadmium, and mercury measurements (n = 3,966). Odds ratios (ORs) for periodontitis were calculated for log-transformed blood metal levels and quartiles thereof after covariate adjustment. In a logistic regression analysis using log-transformed blood lead and mercury levels as independent variables after covariate adjustment, including blood lead, mercury, and cadmium, the ORs and 95 % CI values in men for having periodontitis with doubling of blood lead and mercury were 1.699 (1.154-2.503) and 1.394 (1.057-1.838), respectively. Furthermore, in a logistic regression analysis using tertiles of blood lead and mercury as independent variables after covariate adjustment, the ORs and 95 % CIs of men for having periodontitis in the highest tertile were 1.756 (1.184-2.604) and 1.575 (1.507-2.347), respectively. ORs in the logistic regression analysis for men using log-transformed blood cadmium or the tertile of blood cadmium as independent variables after covariate adjustments were not statistically significant in either model. Unlike men, ORs in the logistic regression analyses for women using the same independent variables after covariate adjustment were not statistically significant in any blood metal analysis. The association between blood lead and mercury levels and periodontitis was significant regardless of the type of variable (continuous or categorical) in the Korean male population.