Associations between achieving treatment targets and functional and economic outcomes in patients with rheumatoid arthritis: retrospective cohort analyses of BRASS registry data

Objectives This study evaluated the associations between achieving treatment goals and patient-reported outcomes (PROs) and healthcare resource utilisation (HCRU) among patients with rheumatoid arthritis (RA) on advanced treatment. Design Retrospective cohort analyses of deidentified data from an established registry. Setting US-based single-centre registry between 2003 and 2024. Participants Data from patients with RA in the Brigham and Women’s Hospital Rheumatoid Arthritis Sequential Study registry were analysed using multivariable regression analyses. Patients were classified into four groups based on Clinical Disease Activity Index (CDAI) scores at baseline and 1 year (consistently at/not at target, gain or lose target). Patients who were consistently at target were further classified into remission, very low disease activity (LDA) and LDA subgroups. Primary and secondary outcome measures PROs (Multidimensional Health Assessment Questionnaire (MDHAQ) overall, pain, fatigue scores) and HCRU (surgery rates, durable medical equipment (DME) use) were assessed over 2 years. The primary endpoint compared MDHAQ PROs and surgery and DME HCRU among the four primary groups. The secondary endpoint assessed the association between maintaining LDA and achieving remission at follow-up with PROs and HCRU. Results Among 637 patients with CDAI data, 257 (40%) had LDA at baseline; 57 (22%) lost target at 1 year. Of 380 (60%) patients with CDAI >10 at baseline, 115 (30%) attained LDA. Patients not attaining LDA had higher surgery risk, DME use and MDHAQ scores. Of 200 (31%) patients with LDA at baseline and 1 year, 89 (45%) achieved remission, 79 (40%) very LDA and 32 (16%) LDA. Remission was associated with reduced DME use (adjusted OR (AOR) 5.4 (95% CI 1.9 to 15.4) at year 1 and AOR 4.4 (95% CI 1.7 to 11.1) at year 2) and improved MDHAQ scores compared with LDA (overall unadjusted mean 0.07 vs 0.5 at year 1 and 0.09 vs 0.4 at year 2; p<0.001), with no differences in surgery rates (AOR 1.9 (95% CI 0.7 to 5.6) at year 1 and AOR 1.9 (95% CI 0.8 to 4.4) at year 2). Conclusions Achieving and maintaining LDA is challenging for patients with RA but leads to better functional outcomes and reduced DME use. Patients who achieve remission have further improvements.