Background We previously reported that the presence of anti-Ro/SS-A antibody (anti-Ro) was an independent factor for poor clinical response to TNF-alpha inhibitors in patients with rheumatoid arthritis (RA).
Objectives To investigate factors associated with normalized physical function, and clinical remission determined by simplified disease activity index (SDAI) at 54 weeks of infliximab (IFX) treatment in patients with RA.
Methods We studied 114 patients with RA treated with IFX, and prospectively examined SDAI, Disease Activity Score in 28 joints (DAS28)/CRP, and modified Health Assessment Questionnaire Disability Index (mHAQ-DI). The clinical remission was defined with simplified disease activity index (SDAI) ≤3.3, and normal physical function was defined by mHAQ-DI<0.5. The baseline characteristics of categorical variables, including (anti-Ro), were compared at 54 weeks.
Results Among 114 patients, 20 patients were withdrawn from this study because they had discontinued by 54 weeks (one was infection, one was reaction of allergy, and others were stopped IFX because of no efficacy). Age, gender, duration, SDAI and DAS28 at baseline were 50.14±13.15, 79 female/15male, 9.40±7.98, 4.19±1.14, and 25.43±12.78, respectively. In 94 patients, 17 (18.1%) and 33 (35.1%) were achieved remission defined with SDAI and DAS28/CRP, respectively. Normalized physical function, mHAQ<0.5, was recognized in 65 patients (69.1%, HAQ remission group). Logistic regression analysis revealed that characteristics mHAQ ≥0.5, the presence of secondary Sjogren’s syndrome, and positive anti-Ro at baseline were significantly associated with normalized physical function (OR 5.83; 95%CI 1.96-17.26, OR 3.62; 95%CI 1.12-11.67, and OR 4.28; 95%CI 1.35-13.53, respectively). As regards other baseline characteristics: age, gender, duration, dose of methotrexate, dose of prednisolone, SDAI, DAS28, titer of anti-cyclic citrullinated peptide antibody and values of rheumatoid factor, there was no significant difference between the groups. On the other hand, low mHAQ, and low ESR, were independently associated with achievement of SDAI remission at 54 weeks (p=0.0098, and p=0.027, respectively).
Conclusions The prevalence of secondary SS and the presence of anti-Ro/SS-A antibodies before IFX treatment might associate with the outcome of poor physical function. To attain SDAI remission and normal physical function, tight control is necessary to prevent irreversible physical dysfunction.
Disclosure of Interest None Declared