Objective: We wanted to investigate the incidence of serious infections among the rheumatoid arthritis (RA) patients who were treated with tumor necrosis factor Ձ (TNF-Ձ) antagonists
Methods: We enrolled the 175 RA patients who were treated with TNF-Ձ antagonists for at least 3 months during February 2003 to July 2008, and these patients were in the SMART-b cohort of Kangnam St. Mary's hospital. Patients were prescribed infliximab, etanercept or adalimumab. The data was retrospectively collected.
Results: The incidence of serious infections among the RA patients treated with TNF-Ձ was significantly increased according to the survival analysis, as compared with that of those patient treated with conventional DMARDs (p＜0.01). The most common serious infection was pneumonia. There was no significant difference in the incidence of serious infections among the three TNF-Ձ antagonists used in this study (p=0.96). But the serious infections occurred more often in the patients who received more than 10 mg methotrexate (MTX) per week (p=0.02).
Conclusion: RA patients treated with TNF-Ձ antagonists had a higher incidence of serious infection. Therefore, close monitoring for serious infection is needed for RA patients who are receiving TNF-Ձ antagonists.

Keywords: Rheumatoid arthritis, Serious infection, TNF-Ձ, antagonists