Abstract
BACKGROUND: Excessive interleukin-6 (IL-6) production in rheumatoid arthritis (RA) leads to joint destruction, inflammation, and systemic symptoms. IL-6 inhibitors alleviate symptoms. C-reactive protein (CRP), an inflammation biomarker, correlates with RA activity. In this study, we assess IL-6 and CRP levels in RA patients to understand their association with disease activity. MATERIALS AND METHODS: This cross-sectional study was conducted at a tertiary care hospital in central India for 15 months, from July 2022 to September 2023. The study involved 75 participants diagnosed with RA and receiving outpatient treatment. Exclusion criteria included anti-IL-6 drug treatment, bedridden individuals, proxy patients, and those without consent. Disease activity was assessed using the 28-joint disease activity score (DAS28), while IL-6 and CRP levels were measured following the standard procedures. RESULTS: The average CRP levels were found to be 51.67 ± 47.49 mg/L, while IL-6 levels averaged 65.16 ± 43.67 pg/ml. The results revealed a substantial positive correlation between IL-6 levels and DAS28 (r = 0.603, p value < 0.001), indicating a significant association. Additionally, a moderate correlation between CRP levels and DAS28 (r = 0.493, p value < 0.001) highlighted a significant relationship between these variables. CONCLUSIONS: The analysis showed that higher IL-6 levels were associated with increased disease activity and suggested IL-6 as a valuable indicator for assessing RA severity. Also, CRP levels had a moderate correlation with disease activity. Overall, IL-6 is a better marker for disease activity when compared to CRP levels in patients with RA.