Periodontal health and chitinase 3-like-1 levels in autoimmune rheumatic diseases and osteoarthritis: a pilot study

Autoimmune rheumatic diseases (AIRD), such as rheumatoid arthritis (RA), often co-exist with periodontitis (PD). Both diseases share inflammatory pathways and common risk factors, suggesting a potential interplay. This study evaluates the association between periodontal health and chitinase 3-Like-1 (CHI3L1), a serological marker of cartilage damage, in patients with or without AIRD. In a cross-sectional design, 36 participants (AIRD patients and controls) underwent rheumatological and periodontal assessments. Clinical data included inflammatory markers, CHI3L1 levels, and detailed periodontal health metrics. Statistical analyses were performed to examine differences between groups and correlations between periodontal indices and CHI3L1 concentrations, adjusting for age and sex. While no significant differences in CHI3L1 levels were found between AIRD and control groups, male participants and individuals with higher Plaque Index (PI) scores exhibited significantly elevated CHI3L1 concentrations. Linear regression indicated PI as a significant predictor of CHI3L1 levels, with a 62% increase per PI unit. The AIRD group showed higher inflammatory marker levels overall. CHI3L1 levels correlated with the level of oral hygiene in patients in our study, with higher concentrations observed in individuals with poorer oral health. These findings indicate that CHI3L1 is associated with periodontitis independently of the presence of AIRD in patients presenting with joint pain. Further longitudinal studies are needed to clarify causal relationships and to determine whether improving periodontal health can reduce systemic inflammation in patients with AIRD.