Objective: To identify predictors of radiographic progression in a 2-year randomized, double-blind clinical study (CIMESTRA) of patients with early rheumatoid arthritis (RA).
Methods: Early RA patients (N=130) were treated with methotrexate, intra-articular betamethasone and cyclosporine/placebo-cyclosporine. Baseline magnetic resonance imaging (MRI) of the wrist (wrist-only-group:N=130) or MRI of wrist and MCP-joints (wrist+MCP-group:N=89) (OMERACT RAMRIS), x-rays of hands, wrists and forefeet (Sharp/vdHeijde Score (TSS)), disease activity score (DAS28), anti-cyclic-citrullinated-peptide-antibodies (anti-CCP), HLA-DRB1-shared-epitope (SE) and smoking status were assessed. Multiple regression analysis was performed with delta-TSS (0-2 years) as dependent variable, and baseline DAS28, TSS, MRI bone oedema score, MRI synovitis score, MRI erosion score, anti-CCP, smoking, SE, age and gender as explanatory variables.
Results: Baseline values: median DAS28: 5.6 (range: 2.4-8.0); anti-CCP positive: 61%; radiographic erosions: 56%. At 2 years: DAS28: 2.0 (0.5-5.7), in DAS-remission: 56%, radiographic progression: 26% (wrist+MCP-group, similar for wrist-only-group). MRI bone oedema score was the only independent predictor of delta-TSS (wrist+MCP-group: coefficient=0.75 (95%CI: 0.56-0.97), p<0.00001; wrist-only-group: coefficient=0.56 (0.41-0.77), p<0.00001). Bone oedema score explained 41% of the variation in the progression of TSS (wrist+MCP-group), 25% in wrist-only-group, (Pearson's r=0.64 and r=0.50, respectively). The results were confirmed by sensitivity analyses.
Conclusion: In a RCT aiming at remission in early RA patients, baseline RAMRIS MRI bone oedema score of MCP and wrist joints (and of wrist only) was the strongest independent predictor of radiographic progression in hands, wrists and forefeet after 2 years. MRI synovitis score, MRI erosion score, DAS28, anti-CCP, SE, smoking, age and gender were not independent risk factors.