Do Disease-Modifying Anti-rheumatic Drugs and Exercise Therapy Have a Combined Effect on Disease Activity in Patients with RA? A Scoping Review

Purpose of Review In addition to disease-modifying anti-rheumatic drug (DMARD) treatment, exercise is increasingly promoted in patients with rheumatoid arthritis (RA). Although both are known to reduce disease activity, few studies have investigated the combined effects of these interventions on disease activity. The aim of this scoping review was to provide an overview of the reported evidence on whether a combined effect-i.e., a greater reduction in disease activity outcome measures-can be detected in studies where an exercise intervention was performed in addition to the DMARD treatment in patients with RA. This scoping review followed the PRISMA guidelines. A literature search was performed for exercise intervention studies in patients with RA treated with DMARDs. Studies without a non-exercise control group were excluded. Included studies reported on (components of) DAS28 and DMARD use and were assessed for methodological quality using version 1 of the Cochrane risk-of-bias tool for randomized trials. For each study, comparisons between groups (i.e., exercise + medication vs. medication only) were reported on disease activity outcome measures. Study data related to the exercise intervention, medication use, and other relevant factors were extracted to assess what may have influenced disease activity outcomes in the included studies. Recent Findings A total of 11 studies were included of which 10 between-group studies on DAS28 components were made. The remaining one study focused on within-group comparisons only. Median duration of the exercise intervention studies was 5 months, and the median number of participants was 55. Six out of the 10 between-group studies reported no significant differences between groups in DAS28 components between exercise + medication vs. medication only. Four studies showed significant reductions in disease activity outcomes for the exercise + medication group compared with the medication-only group. Most studies were not adequately designed methodologically in order to investigate for comparisons of DAS28 components and had a high risk of multi-domain bias. Whether the simultaneous application of exercise therapy and DMARD medication in patients with RA has a combined effect on disease outcome remains unknown, due to weak methodological quality of existing studies. Future studies should focus on the combined effects by having disease activity as the primary outcome.