Adipokine Profile on Joint and Periodontal Conditions in First-degree Relatives of Patients with Rheumatoid Arthritis

Background: Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by joint inflammation and destruction. Objective: Establish the association between Porphyromonas gingivalis (P. gingivalis) infection, body mass index (BMI), joint involvement, and serum adipokines in first-degree relatives (FDR) of patients with rheumatoid arthritis (RA). Methods: The cross-sectional study evaluated 124 FDR and 124 healthy controls (HC). The clinical examination included joint and radiographic evaluation and calculation of BMI. Serum adipokine levels were measured (leptin, vaspin, adiponectin, resistin, and adipsin), as were the erythrocyte sedimentation rate, C-reactive protein, and anti-citrullinated protein antibodies. Investigations were performed to detect P. gingivalis, and anti-P. gingivalis antibodies. Statistical analyses were performed to confirm associations. Results: Leptin levels in FDR were associated with BMI >25 (OR, 2.64; 95%CI, 1.17-5.97; P=0.019), radiographic damage (Simple Erosion Narrowing Score [SENS])/hands, total SENS, and joint space narrowing in feet (P=0.037, 0.026, 0.020, respectively). FDR had more tender joints (P=0.018); this finding was associated with high levels of leptin and resistin and low levels of adipsin (P=0.040, 0.040, and 0.019, respectively). The presence of P. gingivalis was related to FDR, low levels of adipsin, resistin, adiponectin, and a trend toward higher levels of leptin (P=0.002, 0.001, 0.003, and 0.060, respectively), whereas anti-P. gingivalis antibodies were related to low levels of adipsin (P=0.001). Conclusion: In FDR, serum adipokine levels were associated with overweight and the presence of P. gingivalis. Adipokine levels were also associated with joint involvement. Hence, adipokines may be involved in the pathogenesis of RA in FDR and warrant further investigation.