RESUMEN
Objective: To analyze the influences of leukocytes on improving blood glucose control in patients with type 2 diabetes mellitus (T2DM) and periodontitis after periodontal mechanical therapy. Methods: Thirty-five patients visiting Peking University Third Hospital from March 2011 to August 2012, as well as thirty-four patients visiting Peking University Hospital of Stomatology from March 2011 to August 2012 and December 2016 to December 2018 were selected in this research. These subjects were non-smokers, and with moderate to severe chronic periodontitis and T2DM. The full set of periodontal examinations including probing depth (PD), attachment loss (AL), bleeding index (BI) and plaque index (PLI) were conducted. Besides, counts of white blood cells (WBC), parameters of glucose and lipids metabolites such as fasting blood glucose (FBG), glycosylated hemoglobin (HbA1c), total cholesterol (TC), triglyceride (TG), high density lipoprotein (HDL) and low density lipoprotein (LDL) in serum were examined before treatment. Then, oral hygiene instruction, scaling and root planing (SRP) were carried out. Three months after SRP, the baseline examinations were repeated in all patients. According to the baseline leukocyte counts, the patients were divided into subgroups: low WBC group (WBC<6.19×109/L) and high WBC group (WBC≥6.19×109/L). Paired t-test for comparison of changes after treatment, analysis of co-variance for comparing the intervention effects between subgroups, and multifactor Iogistic regression analysis were performed. Results: Three months after SRP, all periodontal indexes were significantly improved in both groups. Leukocyte counts decreased significantly in high WBC group (7.64±1.51 vs. 6.89±1.53, P=0.008). In high WBC group, HbA1c (7.67±1.35 vs. 7.18±1.09, P=0.001) and LDL (3.28±0.76 vs. 2.67±0.85, P=0.042) decreased significantly, while there were no such differences in low WBC group. Influence of leukocyte level on HbA1c (OR=0.12, P=0.038) and LDL (OR=0.15, P=0.001) improvement was statistically significant. Hierarchical analysis showed such improvement notably perform in female [HbA1c (OR=0.30, P=0.021), LDL (OR=0.34, P=0.001)] and severe periodontitis group [HbA1c (OR=0.15, P=0.025), LDL (OR=0.24, P=0.017)]. Through interaction test, female and leukocyte counts at baseline had relative excess risk affecting the effect of periodontal intervention on HbA1c (P=0.036) and LDL (P=0.005). Conclusions: SRP could significantly improve the blood glucose and lipid control in patients who had T2DM and chronic periodontitis with relative higher leukocytes level. Female patients with severe periodontitis showed more obviously effects.