Serum matrix metalloproteinase-3 as predictor of joint destruction in rheumatoid arthritis, treated with non-biological disease modifying anti-rheumatic drugs

Background: Rheumatoid factor (RF), anti-citrullinated peptide antibody (ACPA), C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) have been studied extensively as prognostic markers of rheumatoid arthritis (RA). However, despite the fact that matrix metalloproteinase-3 (MMP-3) is linked to RA activity, few studies have evaluated MMP-3 as prognostic marker. Objective: To evaluate the performance of MMP-3 as predictor of joint destruction in RA treated with non-biological disease modifying anti-rheumatic drugs. Methods: In a retrospective study of 58 early to moderate stage RA patients who consulted the Department of Clinical Pathology and Immunology, Kobe University Hospital between May 2002 and April 2009, we evaluated the performance of MMP-3 and other biomarkers as predictors of joint destruction, by comparing them between radiographically progressive and non-progressive group. Results: Serum levels of RF at entry and ACPA, but not MMP-3 at entry, were significantly higher for the progressive group. Ratios of patients with MMP-3 levels higher than healthy control were not significantly different for the two groups. However, cutoff values determined through receiver operating characteristic analysis showed that the ratio of patients with elevated RF was significantly higher in the progressive group (p=0.001), while MMP-3 (p=0.092), ACPA (p=0.052), CRP (p=0.056), and ESR (p=0.069) tended to be more elevated in the progressive group. Multiple logistic regression analysis using the cutoff value identified MMP-3 positive and RF positive, but not ACPA, CRP or ESR, as significant factors for radiographic progression (OR 16.79 [95% CI: 1.34-414.19]). Conclusion: MMP-3 can be a useful marker for prediction of joint destruction.