Total MRI inflammatory score correlates with disease activity measures after aggressive treatment of rheumatoid arthritis

Purpose: MRI is a sensitive imaging modality to investigate “inflammation” in rheumatoid arthritis (RA) joints. Tenosynovitis, synovitis, and bone edema independently correlate with disease activity measures in RA and suggest radiographic progression. The purpose of this study was to evaluate the relationship of clinical disease activity measures with two composite total MRI inflammatory score measures and their components, after 2 or more years of aggressive treatment of RA. Methods: MRI with gadolinium contrast (1.5 Tesla) of the dominant wrist was obtained in 118 early (RA duration 4.1 ± 10.8 months) seropositive or erosive RA patients after completing the TEAR 2-year controlled clinical trial comparing various combinations of MTX, etanercept, HCQ, and SSZ. Clinical disease activity measures were recorded every 12 weeks during the trial and at the time of MRI. MRIs were scored for tenosynovitis (T: range 0-30), synovitis (S: 0-9), and bone marrow edema (BME: 0-42) using published RA MRI(RAMRIS) and tenosynovitis scoring methods. One method of calculating the total MRI inflammatory score was by: T+ S + BME. Another method produced a weighted measure, by taking the actual values of T, S, and BME and dividing by the range for each component. These values were then added together to give the weighted total MRI inflammatory score. Results: After 2 years of aggressive RA treatment, the patients' average age was approximately 51 years. The mean DAS28 and clinical disease activity index (CDAI) fit into the mild disease activity categories, 2.9 and 9.2 respectively. More clinical core set measures correlated significantly with the weighted and unweighted total MRI inflammatory score than with the individual components of the scores (T, S, and BME), and the Rho values were also higher. T correlated significantly with only the physician global and swollen joint count. S correlated with CDAI, physician global, patient global, ESR, pain, stiffness, and arthritis severity. BME correlated with age, CDAI, physician global, stiffness, and swollen joint count. No single correlation coefficient was greater than >0.4. Weighting the MRI inflammatory score components did not improve the correlations. Conclusions: The total composite MRI inflammatory score was shown to correlate better than the individual components of the MRI scores, with residual disease activity as assessed by standard core set measures and patient self-reported pain and stiffness. (Table Presented).