Pain and fatigue in rheumatoid arthritis tied to sitting and standing time
For patients with rheumatoid arthritis (RA), pain and fatigue may both cause and be caused by more sitting time and less standing time, according to a study published in the October issue of Rheumatology.
Ciara M. O’Brien, Ph.D., from the University of Birmingham in the United Kingdom, and colleagues examined longitudinal and bidirectional associations of pain and fatigue with sedentary, standing, and stepping time in patients with RA. Participants undertook identical assessments at baseline and six months (T1 and T2; 104 and 54 participants, respectively). Physical measures were completed and routine clinical assessments were undertaken to characterize RA disease activity.
From T1 to T2, the researchers observed a positive association for change in pain, but not fatigue, with change in sedentary time in a longitudinal bootstrapped regression analysis. A negative association was seen for change in pain and fatigue in relation to standing time. In a longitudinal nonbootstrapped regression analysis, there was a significant positive association noted between change in fatigue and change in sedentary time. A path analysis supported the hypothesized bidirectionality of associations for change in pain and fatigue with change in sedentary time (pain, β = 0.38; fatigue, β = 0.44) and standing time (pain, β = –0.39; fatigue, β = –0.50).
“Future research should employ experimental study designs to test whether replacing sedentary time with standing improves pain and fatigue in RA,” the authors write. “Additionally, investigation into other factors that influence sedentary, standing and stepping time in RA, over and above pain and fatigue, is warranted—particularly, the modifiable determinants of these behaviors which could be targeted in sedentary behavior change interventions.”