Discordance between the predictors of clinical and imaging remission in patients with early rheumatoid arthritis in clinical practice: implications for the use of ultrasound within a treatment-to-target strategy

Objective. To assess the prevalence, relationship between and predictors of clinical and imaging remission in early RA, achieved with treat-to-target management in clinical practice. Methods. A prospective observational study was conducted in patients with new-onset RA. The treatment target was remission by DAS28-CRP < 2.6. Twelve-month outcomes included DAS28-CRP remission, DAS44-CRP remission, ACR/EULAR Boolean remission (BR) and absent or absent/minimal power Doppler activity (PDA) on US of 26 joints (total PDA score = 0 or a (c) 1/21, respectively). Logistic regression was conducted to identify baseline predictors of these outcomes. Results. Of 105 patients with complete 12-month data, the rate of DAS28-CRP remission was 43%, DAS44-CRP remission was 39%, BR was 14%, absent PDA was 40% and absent/minimal PDA was 57%. Among patients achieving clinical remission defined by DAS28-CRP, DAS44-CRP or BR, absence of PDA was observed in 42, 44 and 40%, respectively; absent/minimal PDA was detected in 62, 66 and 67%, respectively. On multivariable analysis, shorter symptom duration, male gender, fewer tender joints and lower disability were associated with the clinical remission definitions. Lack of OA predicted absence of PDA, and lower total baseline PDA predicted absent/minimal PDA. Conclusion. DAS28-CRP remission and absence of PDA were observed in almost half of the patients, but less than a quarter achieved both. Achievement of BR was rare. The low agreement between any of the clinical and imaging outcomes and differences in their predictors highlight the complex interaction between symptoms and synovitis, with implications for treat-to-target management. Long-term follow-up should determine the most appropriate target.