To determine the effects of treatment with sulfasalazine (SSZ) or the combination of methotrexate (MTX) and SSZ on serum matrix metalloproteinase 3 (MMP-3) levels in patients with early rheumatoid arthritis (RA).
Eighty-two patients with early RA (symptoms < 1 year and DMARD-naive at presentation) were selected who had been treated with SSZ (2000 mg/day) or with the combination of MTX (7.5-15 mg/week) and SSZ. Serum MMP-3 levels, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), swollen joint count (SJC), tender joint count (TJC), Ritchie articular index (RAI), and the Disease Activity Score (DAS) were determined at 4 week intervals during a followup of 28 weeks for each treatment group. Response was based on clinical grounds and CRP at 12, 20, and 28 weeks.
SSZ responders (n = 52) had lower baseline values of serum MMP-3, CRP, and ESR, compared to partial/nonresponders (n = 30), but did not differ in joint scores and DAS. In the SSZ responder group all variables decreased. In the SSZ partial/nonresponders, CRP, ESR, and SJC decreased in contrast to serum MMP-3, TJC. RAI, and DAS-3. After addition of MTX all variables decreased in 24 of the 30 patients who had shown a partial or no response taking SSZ. In the SSZ responders there was a delayed decrease in serum MMP-3 compared to CRP.
Serum MMP-3 levels decrease in patients with early RA who respond to SSZ or to the combination of MTX and SSZ. In patients who respond to SSZ the changes in serum MMP-3 levels indicate a delayed response compared to CRP.