[Relationship between matrix metalloproteinase-3 levels and articular destructive changes in early and extended...

To estimate a relationship between matrix metalloproteinase-3 (MMP-3) levels and articular radiographic changes in early and extended rheumatoid arthritis (RA); to analyze the role of this biomarker in predicting the progression of joint destruction in RA.

Forty-five patients with early RA and 42 with extended RA were examined. Radiography of the hands and distal feet was performed before and one year after therapy. Serum MMP-3 levels were measured by an enzyme immunoassay prior to and 12 and 24 weeks after treatment.

After 52 weeks, in the early RA group, 16 patients continued monotherapy with methotrexate (MT); because of its inefficiency, 29 additionally received a biological agent in different follow-up periods. The extended RA group took tocilizumab for 24 weeks, then the drug was discontinued and the patients continued the former therapy with disease-modifying antirheumatic drugs, nonsteroidal anti-inflammatory drugs, and glucocorticosteroids. One year later, radiographic progression was recorded in 20.5 and 22.5% of the patients with early and extended RA, respectively. ROC analysis indicated that in the early RA group the MMP-3 level of more than 34.3 ng/ml at 12 weeks of MT therapy was associated with the radiographic progression of articular destructive changes after 52 weeks of therapy (the area under the curve (AUC) was 0.7; 95% confidence interval (CI) 0.46 to 0.93). In the patients with extended RA, the baseline MMP-3 levels of ≤51.3 ng/ml was related to no radiographic progression following 52 weeks (AUC, 0.587; 95% CI 0.33 to 0.84).

MMP-3 may be regarded as an early marker for joint destruction in RA. The determination of MMP-3 level with other immunological markers may be useful to identify a group of patients who have a potentially severer disease course and need more intensive therapy.