Radiographic Progression in Patients with Rheumatoid Arthritis in Clinical Remission or Low Disease Activity: Results from a Swiss National Registry (SCQM)

Background/Objectives: The therapeutic aim for rheumatoid arthritis (RA) is to control disease activity and prevent radiographic progression. Various clinical scores are used to assess disease activity in RA patients. The DAS 28 score can define states of low disease activity (LDA) and remission. Despite achieving LDA or remission, radiographic progression may, nevertheless, occur. However, the rates and frequency of this occurrence have not been analyzed in detail. (1) To characterize radiographic progression in patients with persistent DAS 28-defined LDA or remission. (2) Analyze the potential benefits of modifying therapeutic strategies in response to observed radiographic progression in patients with persistent LDA or remission. Methods: An analysis was conducted on RA patients enrolled in the SCQM (Swiss Clinical Quality Management) cohort. Persistent LDA or remission was defined as DAS 28 ≤ 3.2 or <2.6, respectively, recorded at two consecutive follow-up time points. Inclusion criteria involved patients with a minimum of two sets of radiographs taken during these LDA and/or remission periods. Radiographic progression was measured using the Ratingen score, a numerical scale ranging from 0 to 190, which quantifies joint erosions. Repair was defined as a decrease in the Ratingen score > 5 points/year, while progression was characterized by an increase of >1, >2, or >5 points change in the Ratingen score within a one-year timeframe. Results: Among 10'141 RA patients, there were 1'447 episodes of remission and 2'614 episodes of LDA, with two sets of X-rays available for assessment during these episodes. The rates of radiographic progression (>5 points change in the Ratingen score per year) were 11.2% for LDA and 8.8% for remission. Therapeutic adaptations were made in 7.0% of patients in remission and 12.9% of patients in LDA following radiographic progression. After radiographic progression despite LDA, loss of LDA was observed in 19% of patients with treatment intensification versus in 8.5% under continued treatment during follow-up within 36 months. Conclusions: We report a considerable rate of radiographic progression occurring in RA patients with LDA or clinical remission. Notwithstanding minor radiographic progression, maintaining therapeutic continuity seemed more favorable than altering the therapeutic regimen.