Serum matrix metalloproteinase-3 levels monitor the therapeutic efficacy in Syrian patients with rheumatoid arthritis

BACKGROUND: The plans for the successful treatment of rheumatoid arthritis (RA) seek to attain low disease activity or reach clinical remission. OBJECTIVE: Our study aimed to compare the serum MMP-3 levels with predictors of response to therapy of rheumatoid arthritis in Syrian patients and explore its worth as a new valuable biomarker for RA therapy outcomes in daily practice. METHODS: Serum samples were gathered from 43 RA patients at diagnosis and 12 weeks of therapy. Related clinical and laboratory tests were estimated, levels of serum MMP-3 were measured by ELISA method and the disease activity was assessed using disease activity scores in 28 joints with an erythrocyte sedimentation rate (DAS28-ESR) before and after therapy. RESULTS: The mean of Serum MMP-3 levels significantly decreased (322.3 ± 43.83 ng/ml) after therapy (12 weeks) in RA patients compared to its mean at baseline (486.49 ± 34.5 ng/ml). There wasn't a statistically significant difference in the mean of MMP-3 levels before and after therapy (P = 0.137) in non-responder patients. Patients who showed a good response (N = 38) presented higher MMP-3 levels at first which subsequently decreased significantly at the 12-week follow-up (P < 0.05). Also, there was a statistically significant difference in MMP-3 levels between the two groups of patients after therapy (P = 0.002). To differentiate between RA patients who responded to therapy and who did not, our results found that the cut-off value of serum MMP-3 was 317.8 ng/ml (sensitivity was 80%, specificity was 73%, AUC was 0.818, 95% CI: 1.114–112.5; P = 0.045) and the best cut-off value of DAS28-ESR was 5.325 (sensitivity 100%, specificity 100%, AUC = 100%,95% CI: 15.2 to 47203.8). CONCLUSION: serum MMP-3 can be added as a novel and valuable biomarker in estimating the therapeutic response in RA patients, but it isn't better than DAS28-ESR.