Objectives: Type 2 diabetes mellitus (T2DM) is a risk factor for periodontal disease. Dysregulated inflammatory responses in T2DM may contribute to increased susceptibility to periodontitis. This study aimed to measure serum, saliva and GCF cytokine concentrations in patients with chronic periodontitis, comparing T2DM patients and non-diabetic controls.
Methods: T2DM patients with chronic periodontitis and non-diabetic controls (age, gender and smoking status matched) were identified following clinical and radiographic examination. Serum, saliva and GCF levels of interleukin-6 (IL-6), tumour necrosis factor-a (TNF-a), IL-1β and interferon-γ (IFN-γ) were measured using a highly sensitive cytokine array (MesoScale Discovery). Glycated haemoglobin (HbA1c) provided a measure of glycaemic control.
Results: Data for 43 T2DM patients and 30 controls are reported. Mean (±SD) age was 49.1±5.8 years, with no significant difference between the groups. 15 patients were smokers (6 in the T2DM group and 7 in the control group). Mean (±SD) cytokine concentrations (below) did not differ significantly between the groups. In both groups IL-1β levels were significantly higher in GCF than serum or saliva (P<0.01).
IL-6 (ng/ml) | TNF-α (ng/ml) | |||||||
GCF | serum | saliva | GCF | serum | saliva | |||
T2DM | 5.89±14.78 | 1.73±4.26 | 3.44±4.06 | T2DM | 5.93±3.58 | 5.79±4.79 | 2.30±2.48 | |
Control | 3.10±3.48 | 1.07±3.02 | 5.48±7.94 | Control | 6.38±5.55 | 3.68±2.16 | 2.96±2.44 | |
IL-1β (ng/ml) | IFN-γ (ng/ml) | |||||||
GCF | serum | saliva | GCF | serum | saliva | |||
T2DM | 387.89±267.16 | 0.16±0.19 | 66.63±65.79 | T2DM | 3.91±4.92 | 3.50±5.22 | 1.10±0.85 | |
Control | 550.69±408.30 | 0.11±0.53 | 58.89±49.14 | Control | 6.11±8.46 | 1.46±3.51 | 1.30±0.89 | |
Mean HbA1c scores were 8.06±1.77% (T2DM) and 5.49±0.30% (controls) and 35% of T2DM patients had poor glycaemic control (HbA1c>8.5%).
Conclusion: No significant differences in cytokine concentrations were detected locally or systemically between T2DM patients and controls. The importance of IL-1β in periodontal pathogenesis is confirmed by the high levels of this cytokine in GCF.