A predictive model for remission and low disease activity in patients with established rheumatoid arthritis receiving TNF blockers

The objective of this study was to identify predictors for remission or low disease activity (LDA) in established rheumatoid arthritis (RA) at 12 months of anti-TNF-alpha therapy. We have performed a prospective observational study in 90 consecutive patients with active RA receiving TNF-alpha inhibitors. Baseline and standard assessments were done every 3 months, including individual parameters (clinical and biological) and composite activity scores (28-joint disease activity score, DAS28). The primary outcome measure was DAS28-based EULAR response criteria. The multivariate logistic regression was used to analyze the association between disease activity and several RA baseline characteristics. Of the RA, 78.8 % was classified as good responders based on the EULAR-DAS28 criteria, 44.4 % RA achieving remission (DAS28 a parts per thousand currency signaEuro parts per thousand 2.6) and 34.4 %, LDA (DAS28 a parts per thousand currency signaEuro parts per thousand 3.2). Parameters associated with an increased likelihood of remission and LDA were initial DAS28-erythrocyte sedimentation rate a parts per thousand currency sign7 (odds ratio (OR) 3.3, 95 % confidence interval (CI) 2.03-5.81; OR 1.8, 95 % CI 1.09-6.68), Health Assessment Questionnaire Disability Index a parts per thousand currency signaEuro parts per thousand 2 (OR 7.0, 95 % CI 1.56-31.91; OR 1.3, 95 % CI 1.03-5.79), C-reactive protein level a parts per thousand currency sign20 mg/l (OR 1.5, 95 % CI 0.29-8.22; OR 0.5, 95 % CI0.08-2.97), rheumatoid factor a parts per thousand currency sign20 IU/ml (OR 18.9, 95 % CI 10.79-38.36; OR 32.9, 95 % CI 4.03-269), anti-cyclic citrullinated peptide antibodies a parts per thousand currency sign40 IU/ml (OR 3.5, 95 % CI 0.67-18.19; OR 1.2, 95 % CI 1.02-1.59), concurrent prednisolone (OR 0.2, 95 % CI 0.05-0.36; OR 0.2, 95 % CI 0.06-0.63), methotrexate or leflunomide (OR 1.6, 95 % CI 1.2-13.53; OR 2.9, 95 % CI 1.20-4.36). A predictive matrix for remission and LDA in established active RA patients receiving TNF-alpha inhibitors was proposed. Further studies are necessary to confirm the value of such matrix in particular RA settings, leading to optimization of the use of anti-TNF-alpha therapy.