BACKGROUND: Patients with RA (Rheumatoid Arthritis) are more sedentary than the general population. Reduction of Sedentary Behaviour (SB) has been suggested as a mean for improvement of health in patients with chronic diseases and mobility problems. Short-term intervention studies have demonstrated that SB can be reduced by behavioural interventions in healthy populations. However, it remains unexplored whether it is valid for patients with RA also. Therefore, the aim of this trial is to investigate the efficacy of an individually tailored, theory-based motivational counseling intervention on reducing daily sitting time in sedentary patients with RA. Additionally, to explore whether a reduction in daily sitting time is associated with reduced pain and fatigue, self-reported physical function, self-efficacy, improved health-related quality of life (HR-QoL) and cardiovascular biomarker levels, and finally to assess the cost-effectiveness of the intervention.

METHODS/DESIGN: For this parallel group randomized trial, 150 patients with RA and at least 5 hours of sitting time per day, will be recruited from a rheumatology outpatient clinic, and block-randomized to the intervention group or the control group receiving usual care. The intervention includes: 1) individual motivational counseling (in total 3 sessions) on reduction of daily sitting time in combination with 2) individual Short Text Message Service (SMS) reminders over a 16-week intervention period. Primary outcome is change in daily sitting time (minutes) from baseline to 16 weeks measured objectively using an ActivPAL® Activity Monitor. Secondary outcomes include fatigue, pain, physical function, HR-QoL, self-efficacy, costs and cost-effectiveness. Furthermore, anthropometric measures will be included as well as measurement of blood pressure and serum lipids. All outcomes are assessed at baseline and repeated after 16 weeks. Follow-up assessments are made at 6 and 18 months post-intervention.

DISCUSSION: The intervention is simple, non-invasive and may be implemented at low costs. If the study confirms the positive results expected, the intervention might be implemented in clinical practice and potentially transferred to other clinical populations.

TRIAL REGISTRATION: ClinicalTrial.gov registration number: NCT01969604 . Date of registration: 17 October 2013.