Mechanisms of change in depression and anxiety within a mind-body activity intervention for chronic pain

Chronic pain is challenging and costly to treat. Depression and anxiety co-occur with chronic pain. Identifying psychosocial mechanisms contributing to emotional outcomes among chronic pain patients can inform future iterations of this intervention.

We examined explanatory mechanisms of change in emotional distress following a mind-body and activity intervention among 82 participants (21 - 79 years old, 65.85% female, 80.48% White). With depression and anxiety as outcomes, we hypothesized that potential mediators would include pain catastrophizing, mindfulness, and pain resilience. We used mixed-effects modeling to assess the indirect effects of time on each outcome variable through hypothesized mediators simultaneously.

Improvements in depression from baseline to post-treatment were most explained by pain catastrophizing (b = -2.53, CI = [-3.82, -1.43]), followed by mindfulness (b = -1.21, CI = [-2.15, -0.46]), and pain resilience (b = -0.76, CI = [-1.54, -1.66]). Improvements in anxiety from baseline to post-treatment were most explained by pain catastrophizing(b = -2.16, CI = [-3.45, -1.08]) and mindfulness (b = -1.51, CI = [-2.60, -0.65]), but not by pain resilience, (b = -0.47, CI = [-1.26, 0.17]).

Findings are limited by the lack of a control group, relatively small sample, and two timepoints. However, findings can guide future mind-body intervention efficacy testing trials.

Pain catastrophizing and mindfulness appear to be important intervention targets to enhance emotional functioning for chronic pain patients, and should be considered simultaneously in interventions for chronic pain.