Objectives: To investigate whether the levels of serum C-reactive protein (CRP), salivary interleukin (IL)-6 and IL-lβ in metabolic syndrome (MS) patients can be potential monitors for inflammation in MS patients with severe periodontitis.
Methods: A total of 114 MS patients and 49 systemically healthy subjects were enrolled. CRP in serum and IL-1β and IL-6 in non-stimulated whole saliva were collected from these patients and subjects and analysed by enzyme-linked immunosorbent assay (ELISA). Dental examinations were performed and the participants completed a questionnaire.
Results: The serum CRP level of MS patients was higher than that of systemically healthy subjects, and increased as the number of components increased (P < 0.05). No difference was observed in the salivary level of IL-6 and IL-1β between MS patients and controls or between MS patients with different components. The level of salivary IL-6 in MS patients with moderate/severe periodontitis was significantly higher than in MS patients with good periodontal health/mild periodontitis (P < 0.05). After adjustment for age, sex and smoking habits, multivariate analysis showed that the corresponding odds ratio (OR) for MS combined with moderate/severe periodontitis was 1.21 (95% confidence interval [CI] 1.04-1.39, P = 0.012) for subjects with high serum CRP and salivary IL-6 and IL-1β were not risk indicators for MS combined with moderate/severe periodontitis.
Conclusions: MS patients might be burdened by high levels of serum CRP. Serum CRP could be a potentially valuable biomarker to detect inflammation in MS patients with severe periodontal disease.
Keywords: inflammation; metabolic syndrome; periodontitis; cytokines.