ASSOCIATION OF MICRO-RNA EXPRESSION PROFILES WITH DISEASE SEVERITY IN RHEUMATOID ARTHRITIS PATIENTS

Background: Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by persistent inflammation, progressive joint destruction, and significant morbidity. Recent evidence suggests that microRNAs (miRNAs), small non-coding RNA molecules involved in gene regulation, may serve as promising biomarkers for disease activity and progression in RA. Objective: To evaluate the association between circulating microRNA expression profiles and clinical severity in patients with rheumatoid arthritis. Methods: A cross-sectional study was conducted over eight months at tertiary care hospitals in Lahore, Pakistan, enrolling 90 adult RA patients diagnosed based on ACR/EULAR 2010 criteria. Clinical disease activity was assessed using the DAS28-ESR score. Plasma levels of miR-146a, miR-155, miR-21, and miR-223 were quantified using real-time PCR. Statistical analyses included Pearson correlation, one-way ANOVA, and post hoc Tukey’s tests to explore associations between miRNA expression and disease severity and inflammatory markers. Results: Higher expression levels of miR-146a (r = 0.48), miR-155 (r = 0.53), miR-21 (r = 0.41), and miR-223 (r = 0.46) significantly correlated with DAS28-ESR scores (p < 0.001 for all except miR-21, p = 0.002). Expression levels increased progressively with disease activity category. Significant positive correlations were also observed between these miRNAs and ESR and CRP values, with miR-155 showing the strongest association. Conclusion: The study establishes a significant association between circulating miRNAs and RA disease severity. These miRNAs, particularly miR-155 and miR-146a, hold potential as non-invasive biomarkers for disease monitoring and personalized treatment strategies in rheumatoid arthritis.