Background ACR/EULAR definitions of remission is recommended to assess clinical outcome to achieve treat to target for RA treatment (1). However, the role of new remission criteria is not still clear as for bio-free remission.
Objectives In order to investigate how Boolean definition criteria for remission in infliximab treatment for rheumatoid arthritis (RA) relate clinical factors, we analyzed bio-free and drug-free remission rate by treatment of infliximab in 212 RA patients.
Methods 212 patients treated with infliximab, 181 female, 31 male, mean age of 59.4 years old, mean disease duration of 13 years, mean MTX dosage of 6.1 mg/weeks and mean PSL dosage of 2.7 mg/day. Up to 3 years after discontinuation of infliximab, remission rate by DAS28 (CRP), SDAI and Boolean definition criteria was investigated. In clinical data, C-reactive protein (CRP), matrix metalloproteinase (MMP)-3, rheumatoid factor and CCP antibody levels were followed up regularly.
Results 32 out of 212 patients (15%) showed bio-free remission including 4 male and 28 female, mean ages of 57.2 years, mean disease duration of 89 months. Less than 5 years of disease duration, bio-free rate was 23% and within 2 years of disease duration, it showed 25%. At 52 weeks, SDAI and Boolean remission criteria were 19% and 15%. All cases of Boolean remission criteria (15%) showed bio-free remission (15%) and correlated with each other significantly (p<0.001) after an average of 2.2 years of treatment of infliximab. On the other hand, drug-free remission was 11 patients (5.2%) with mean age of 55.7 years, mean disease duration of 57 months. An average of three yeas after drug-remission, 2 out of 11 flared and restarted MTX treatment. The related factors of flare-up cases were rheumatoid factor and disease duration. CCP antibody was not changed to normal level in positive cases after drug-free remission.
Conclusions Boolean remission criteria by treatment of infliximab correlated with bio-free remission significantly. Therefore Boolean remission may be useful criteria to predict the bio-free remission in infliximab treatment for RA.
Felson DT, Smolen JS, Wells G, et al. American College of Rheumatology/European League Against Rheumatism provisional definition of remission in rheumatoid arthritis for clinical trials. Arthritis Rheum. 63:573-86,2011.
Disclosure of Interest None Declared