Short- and long-term efficacy of intra-articular injections with betamethasone as part of a treat-to-target strategy in early rheumatoid arthritis:impact of joint area, repeated injections, MRI findings, anti-CCP, IgM-RF and CRP

OBJECTIVE: To investigate the short-term and long-term efficacy of intra-articular betamethasone injections, and the impact of joint area, repeated injections, MRI pathology, anticyclic citrullinated peptide (CCP) and immunoglobulin M rheumatoid factor (IgM-RF) status in patients with early rheumatoid arthritis (RA).METHODS: During 2 years of follow-up in the CIMESTRA trial, 160 patients received intra-articular betamethasone in up to four swollen joints/visit in combination with disease-modifying antirheumatic drugs. Short-term efficacy was assessed by EULAR good response. Long-term efficacy by Kaplan-Meier plots of the joint injection survival (ie, the time between injection and renewed flare). Potential predictors of joint injection survival were tested.RESULTS: 1373 Unique joints (ankles, elbows, knees, metacarpophalangeal (MCP), metatarsophalangeal, proximal interphalangeal (PIP), shoulders, wrists) were injected during 2 years. 531 Joints received a second injection, and 262 a third. At baseline, the median numbers of injections (dose of betamethasone) was 4 (28 mg), declining to 0 (0 mg) at subsequent visits. At weeks 2, 4 and 6, 50.0%, 58.1% and 61.7% had achieved a EULAR good response. After 1 and 2 years, respectively, 62.3% (95% CI 58.1% to 66.9%) and 55.5% (51.1% to 60.3%) of the joints injected at baseline had not relapsed. All joint areas had good 2-year joint injection survival, longest for the PIP joints: 73.7% (79.4% to 95.3%). 2-Year joint injection survival was higher for first injections: 56.6% (53.7% to 59.8%) than for the second: 43.4% (38.4% to 49.0%) and the third: 31.3% (25.0% to 39.3%). Adverse events were mild and transient. A high MRI synovitis score of MCP joints and anti-CCP-negativity were associated with poorer joint injection survival, whereas IgM-RF and C-reactive protein were not.CONCLUSION: In early RA, intra-articular injections of betamethasone in small and large peripheral joints resulted in rapid, effective and longlasting inf