No serological association between Porphyromonas gingivalis or Prevotella intermedia and early spondyloarthritis: analysis from the DESIR cohort
摘要
Porphyromonas gingivalis and Prevotella intermedia are key oral pathogens implicated in periodontal disease and have been associated with rheumatoid arthritis and specific categories of juvenile idiopathic arthritis. Whether oral dysbiosis involving Porphyromonas gingivalis or Prevotella intermedia contributes to axial spondyloarthritis pathogenesis remains unclear. We evaluated Porphyromonas gingivalis- and Prevotella intermedia-specific IgG titres across early axial spondyloarthritis phenotypes within the DESIR cohort and assessed the potential influence of smoking status. Serum samples from 554 participants in the DESIR cohort were analyzed. Anti-Porphyromonas gingivalis and anti-Prevotella intermedia IgG titres were measured using a validated in-house enzyme-linked immunosorbent assay. Patients were classified into axial spondyloarthritis, axial spondyloarthritis with psoriasis, axial spondyloarthritis with inflammatory bowel disease, undifferentiated axial spondyloarthritis, or chronic low back pain controls. Antibody titres were compared using non-parametric tests. In addition, multivariable logistic and linear regression analyses were performed adjusting for age, sex, BMI and smoking status. Anti-Porphyromonas gingivalis and anti-Prevotella intermedia IgG titres did not differ significantly across axial spondyloarthritis phenotypes or between axial spondyloarthritis subgroups and chronic low back pain controls (Porphyromonas gingivalis: p = 0.622; Prevotella intermedia: p = 0.491). These findings remained unchanged after multivariable adjustment for age, sex, BMI, and smoking status (all p > 0.1). Smoking status did not influence serological patterns in any group. Distributional analyses confirmed strong overlap in antibody titres across all phenotypes, with no subgroup showing a distinct P. gingivalis or P. intermedia serological signature. In this large early axial spondyloarthritis cohort, antibody responses to Porphyromonas gingivalis and Prevotella intermedia did not differ across phenotypes and showed no detectable serological association with axSpA. These findings did not support a major role of Porphyromonas gingivalis - or Prevotella intermedia–related systemic humoral responses in early axial spondyloarthritis, although they did not exclude a broader role of mucosal dysbiosis in disease pathogenesis.