Effect of Fatigue, Older Age, Higher Body Mass Index, and Female Sex on Disability in Early Rheumatoid Arthritis in the Treatment‐to‐Target Era

To compare disease activity and disability over 2 years in early rheumatoid arthritis (RA) before and after implementation of treat‐to‐target therapy and identify predictors of adverse outcome. The Yorkshire Early Arthritis Register (YEAR) recruited 725 patients with early RAbetween 2002 and 2009, treated with a step‐up approach. The Inflammatory Arthritis Continuum study (IACON) recruited cases between 2010 and 2014 and treated to target. A total of 384 IACONcases met 2010 American College of Rheumatology/European League Against Rheumatism criteria. Latent growth curves of change in Disease Activity Score in 28 joints (DAS28) and the Health Assessment Questionnaire (HAQ) were compared between YEARand IACON. Latent class growth analysis identified trajectories of change. Baseline predictors of trajectories were identified using logistic regression. The mean DAS28 over 2 years was lower in IACONthan in YEAR. Latent trajectories of HAQchange in YEARwere high stable (21% of cohort), moderate reducing (35%), and low reducing (44%). Only moderate reducing (66%) and low reducing (34%) were seen in IACON. In both cohorts, female sex and fatigue predicted adverse HAQtrajectories (high stable and moderate reducing). Odds ratios (ORs) for moderate reducing compared to low reducing for women were 2.58 (95% confidence interval [95% CI] 1.69, 4.49) in YEARand 5.81 (95% CI2.44, 14.29) in IACON. ORs per centimeter fatigue visual analog score were 1.13 (95% CI1.07, 1.20) in YEARand 1.16 (95% CI1.12, 1.20) in IACON. Treat‐to‐target therapy gave more favorable trajectories of change in DAS28 and HAQ, but adverse HAQtrajectory was more likely in women with greater fatigue, suggesting such patients would benefit from interventions to improve function as well as reduce inflammation.