To investigate the longitudinal relationship between disease activity and self-reported physical activity (PA) in patients with early rheumatoid arthritis during the first year of treatment with combination therapy.
PA was measured with the Short Questionnaire to Assess Health-Enhancing Physical Activity at baseline, 13 weeks, 26 weeks, and 52 weeks after start of treatment in the context of the Combinatietherapie Bij Reumatoïde Artritis-Light trial. The reported PA classified patients as meeting or not meeting the World Health Organization (WHO) PA guideline (cutoff: 150 minutes of moderate-to-intense activity per week). Other measurements included the Disease Activity Score (DAS). Since both treatment arms showed equal treatment effect, these were analyzed as 1 group with simple before-after analyses and generalized estimating equations (GEE).
In these analyses, 140 patients (86% of the trial population, 66% women, mean age 52 years) with complete data were included. At entry, 69% of the patients met the WHO PA guideline, increasing to 90% at week 13, and remaining stable at 89% after 1 year (P < 0.001). Mean DAS improved from 4.0 to 1.8 during the first year of treatment (P < 0.001). In GEE analyses, DAS decreases were significantly associated with PA increases (P = 0.008). Patients with clinically relevant responses (expressed as DAS remission, European League Against Rheumatism good response or American College of Rheumatology criteria for 70% improvement response) showed higher PA levels compared to nonresponders, regardless of the definition of response, for both the WHO and Dutch PA guideline.
Early rheumatoid arthritis patients using combination therapy improved both disease activity and PA, a beneficial effect persisting for at least 1 year.