Effects of psychosocial factors on monitoring treatment effect in newly diagnosed rheumatoid arthritis patients over time: response data from the tREACH study.

OBJECTIVES: To investigate whether, apart from effects of patient- and disease-related factors, psychosocial factors have additional effects on disease activity; and which factors are most influential during the first year of treatment in early rheumatoid arthritis (RA).

METHOD: The study assessed 15 month follow-up data from patients in tREACH, a randomized clinical trial comparing initial triple disease-modifying anti-rheumatic drug therapy to methotrexate monotherapy, with glucocorticoid bridging in both groups. Patients were evaluated every 3 months and treated to target. Associations between Disease Activity Score (DAS) at 3, 9, and 15 months and psychosocial factors (anxiety, depression, fatigue, and coping with pain) at the previous visit were assessed by multivariable linear regression correcting for demographic, clinical, and treatment-related factors.

RESULTS: At 3, 9, and 15 months of follow-up, 265, 251, and 162 patients, respectively, were available for analysis. Baseline anxiety and coping with pain were associated with DAS at 3 months; coping with pain at 6 months was associated with DAS at 9 months, and fatigue at 12 months with DAS at 15 months. Psychosocial factors were moderately correlated. Effects on DAS were mainly due to tender joint count and global health.

CONCLUSION: Psychosocial factors have additional effects on DAS throughout the first year of treatment in early RA. A change was observed from anxiety and coping with pain at baseline being associated with subsequent DAS towards fatigue being associated with subsequent DAS at 12 months. Owing to the explorative nature of this study, more research is needed to confirm this pattern.