[Preliminary study on the relationship between different blood glucose levels and periodontitis in patients with diabetes mellitus type 2].

To determine the correlation between the diabetes mellitus control and periodontitis. This study was a cross-sectional survey using stratified system sampling model design. The target population was the patients with diabetes investigated from May to July 2018 in Huangpu District of Shanghai. In the present study, severe periodontitis was defined as at least at two sites in different quadrants with probing depth (PD)≥6 mm and clinical attachment loss (CAL)≥ 5 mm. Edentulous induced by periodontitis were also classified as severe periodontitis and the others were classified as non-severe periodontitis subjects. Diabetes control levels were divided into the following three groups: poorly controlled group [glycated hemoglobin (HbA1c)>7.5% and fasting blood glucose (FPG)>7.0 mmol/L], well controlled group (6.5%≤HbA1c≤7.5％ or 6.1 mmol/L≤FPG≤7.0 mmol/L) and ideally controlled group (HbA1c<6.5% and FPG<6.1 mmol/L). SPSS 25.0 was used for statistical analysis. Chi square test was used for demographic data and frequency distribution, α=0.05, two-sided test. Ordinal regression model was used for PD and diabetes control status to balance confounding factors (including age, gender, education and smoking status). After matching the propensity scores between severe periodontitis group and non-severe periodontitis group, logistic regression analysis was used to analyze the level of diabetes control and periodontitis. A total of 5 220 adults over the age of 18 with a medical history of diabetes participated in the survey, of which 3 064 subjects with diabetes mellitus type 2 (T2DM) who were given both oral and laboratory examinations and were included in this study. Statistics showed that the prevalence of moderate and severe periodontitis was 10.57% (324/3 064). In the severe periodontitis group, 79.01% (256/324) of the subjects were over 65 years old, 55.56% (180/324) were male, 58.33% (189/324) had lower education level than high school level, and 21.91% (71/324) were smokers, which were significantly higher than those in the non-severe periodontitis group (0.01). In different T2DM status groups, the percentage of severe periodontitis increased with the aggravation of T2DM status. In severe periodontitis group, the proportion of patients with poor glycemic control was higher. T2DM patients with poor glycemic control accounted for 68.52% (222/324) in severe periodontitis group, which was significantly higher than the proportion of non-severe periodontitis group of 60.99% (1 671/2 740) (0.05). The regression coefficient of PD was 0.191, and PD had a significant negative effect on the level of blood glucose (0.01). There was a significant positive correlation between diabetes glycemic control and severe periodontitis (2.800, 0.05). In Huangpu District of Shanghai, among T2DM patients, the age of severe periodontitis group was higher than that of non-severe periodontitis group, most of them were male, with lower education level and higher proportion of smoking. The severity of diabetes was related to periodontitis and the proportion of severe periodontitis was higher in patients with poor glycemic control.