To clarify whether magnetic resonance imaging (MRI) bone edema predicts the development of rapid radiographic progression (RRP) in the Nagasaki University Early Arthritis Cohort of patients with early-stage rheumatoid arthritis (RA).
Patients with early-stage RA (n = 76) were enrolled and underwent 1.5-T MRI of both wrists and finger joints. Synovitis, bone edema, and bone erosion were evaluated using the Rheumatoid Arthritis Magnetic Resonance Imaging Scoring (RAMRIS). RRP was defined as an annual increment > 3 at 1 year by the Genant-modified Sharp score of plain radiographs. A multivariate logistic regression analysis was performed to establish the risk factors for RRP.
Median disease duration at enrollment was 3 months. RRP was found in 12 of the 76 patients at 1 year. A univariate analysis revealed that matrix metalloprotease-3, RAMRIS bone edema score, and RAMRIS bone erosion score were associated with RRP. Multivariate logistic regression analyses demonstrated that the RAMRIS bone edema score at enrollment (5-point increase, OR 2.18, 95% CI 1.32-3.59, p = 0.002) was the only independent predictor of the development of RRP at 1 year. A receiver-operating characteristic analysis identified the best cutoff value for RAMRIS bone edema score as 5. RRP was significantly rare among the patients with a RAMRIS bone edema score < 5 at enrollment (2 from 50 patients).
Our findings suggest that MRI bone edema is closely associated with the development of RRP in patients with early-stage RA. Physicians should carefully control the disease activity when MRI bone edema is observed in patients with early RA.