The Incidence of Serious Infection among Rheumatoid Arthritis Patients Exposed to Tumor Necrosis Factor Antagonists

Objective: We wanted to investigate the incidence of serious infections among the rheumatoid arthritis (RA) patients who were treated with tumor necrosis factor α (TNF-α) antagonists.Methods: We enrolled the 175 RA patients who were treated with TNF-α 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-α 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-α 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).