Treatment mechanism and outcome decoupling effects in cognitive therapy, mindfulness-based stress reduction, and behavior therapy for chronic pain.
James Gerhart, John W Burns, Beverly Thorn, Mark Jensen, James Carmody, Francis Keefe
Pain February 1, 2025 DOI: 10.1097/j.pain.0000000000003374
Summary
Cognitive therapy, mindfulness-based stress reduction, and behavior therapy significantly improve chronic low back pain, with 521 participants experiencing notable changes. Initial assessments showed strong associations between treatment mechanisms and outcomes during the first third of treatment, but these links weakened over time, becoming nonsignificant by the last third. This trend was not observed in those receiving treatment as usual. By midtreatment, participants learned that negative thoughts and pain spikes need not adversely affect their overall experience, highlighting the evolving nature of therapeutic effects.
Abstract
Findings suggest that cognitive therapy (CT), mindfulness-based stress reduction (MBSR), and behavior therapy (BT) for chronic pain produce improvements through changes in putative mechanisms. Evidence supporting this notion is largely based on findings showing significant associations between treatment mechanism variables and outcomes. An alternative view is that treatments may work by reducing or decoupling the impact of changes in mechanism variables on changes in outcomes. We examined the degree to which relationships between previous changes in potential treatment mechanisms and subsequent changes in outcomes changed as treatment progressed and vice versa. Cognitive therapy, MBSR, BT, and treatment as usual (TAU) were compared in people with chronic low back pain (N = 521). Eight individual sessions were administered with weekly assessments of putative treatment mechanisms and outcomes. Lagged analyses revealed mechanism × session number interactions and outcome × session number interactions, such that associations between mechanism and outcome variables were strong and significant in the first third of treatment, but weakened over time and became nonsignificant by the last third of treatment. These effects were similar across treatment conditions but did not emerge among people undergoing TAU. Results suggest that during the course of CT, MBSR, and BT, the links between changes in treatment mechanism variables became decoupled from subsequent changes in outcomes and vice versa. Thus, starting by midtreatment and continuing into late treatment, participants may have learned through participation in the treatments that episodes of maladaptive pain-related thoughts and/or spikes in pain need not have detrimental consequences on their subsequent experience.