Impact of Gender on the Relationship Between Obesity and Inflammatory Markers in Rheumatoid Arthritis

Abstract

Background: Obesity is associated with elevated inflammatory markers such as C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), which can complicate disease activity assessment in rheumatoid arthritis (RA). Gender specific differences in fat distribution and immune response may further modulate this relationship. Objectives: To evaluate the impact of gender on the association between obesity and systemic inflammatory markers (CRP, ESR) in patients with RA in remission or low disease activity, compared to obese non-RA controls. Methods: A cross-sectional study was conducted on 126 RA patients (70 obese and 56 non-obese) and 50 obese healthy controls. RA diagnosis was based on 2010 ACR/EULAR criteria. Patients were grouped by gender and obesity status. CRP and ESR levels were compared using Mann–Whitney U tests, with subgroup analysis by gender. Results: Obese RA males exhibited significantly higher CRP and ESR levels compared to non obese RA males (p = 0.004, 0.038, respectively). In RA females, CRP was moderately elevated in obese compared to non-obese (p = 0.041), while ESR differences were non-significant. Obese male controls also showed elevated inflammatory markers, suggesting adiposity-related inflammation even in the absence of RA. Overall, visceral fat in males appeared to exert a stronger influence on systemic inflammation. Conclusion: Gender significantly influences the inflammatory response to obesity in RA. Male patients, particularly those with obesity, show disproportionately elevated CRP and ESR levels that may not reflect actual disease activity. This underscores the need for gender-specific interpretation of inflammatory markers to avoid misclassification and overtreatment in RA.