Interleukin-6 Levels in Iraqi Patients with Rheumatoid Arthritis: A Case-Control Study

Abstract

Background: rheumatoid arthritis (RA) is a chronic, systemic autoimmune inflammatory disease, (IL-6) makes a contribution to both local and systemic inflammation. Aims:  to examine serum IL-6 concentrations between Iraqi patients with RA and control samples. To study associations with specific clinical variables. Material And Method: the study involved 76 participants, 36 diagnosed as RA patients and 40 as a control. CRP, IL-6, demographic and clinical variables were recorded. Statistical analysis was accomplished using independent-sample t-test, chi-square test and Spearman correlation. Result: Mean IL-6 was 14.13 ± 12.50 pg/mL in the RA group and 17.30 ± 14.28 pg/mL in controls; the difference was not statistically significant (P=0.306). Mean CRP was 7.10 ± 7.37 mg/L in RA patients and 8.94 ± 8.54 mg/L in controls (P=0.317). Within RA patients, IL-6 was very strongly correlated with CRP (Spearman ρ=0.998, P<0.001), whereas its correlation with disease duration was not significant (ρ=0.117, P=0.497). Conclusions: In this dataset, serum IL-6 was not significantly different between the provisionally defined RA and control groups, although IL-6 closely tracked CRP among RA records. The findings should be interpreted in light of the provisional group coding and the absence of DAS28 data.