Serum Levels of Matrix Metalloproteinase (MMP) 9, a Risk Factor for Acute Coronary Syndrome, Are Reduced Independently of Serum MMP-3 by Anti-TNF-α Antibody (Infliximab) Therapy in Patients With Rheumatoid Arthritis

Matrix metalloproteinase 9 (MMP-9) is a risk factor for cardiovascular events. The serum MMP-9 levels were measured before and 2 weeks after treatment with infliximab (3 mg/kg) in 12 rheumatoid arthritis (RA) patients. The serum average MMP-9 level was 238.5 ng/ml before treatment with infliximab in RA patients (normal range: less than 43.8 ng/ml). Infliximab reduced the serum average MMP-9 level significantly (161.66 ng/ml, P = 0.0425). The serum MMP-9 level was high in the RA patients with active disease, and it was reduced by infliximab independently of the reduction in disease activity. Thus, infliximab may reduce the risk of cardiovascular events directly. Keywords:: rheumatoid arthritis, matrix metalloproteinase 9, acute coronary syndrome