Youth with Chronic Pain and Postural Orthostatic Tachycardia Syndrome (POTS): Treatment Mediators of Improvement in Functional Disability.

Intensive pain rehabilitation programs are effective in increasing functioning for youth with chronic pain (CP). However, the utility of such programs for youth with CP and co-morbid postural orthostatic tachycardia syndrome (POTS) is rarely examined. In addition, studies examining mediators of treatment for CP are sparse. This paper compares treatment outcomes for youth with CP (n = 117) and youth with CP + POTS (n = 118). Additionally, depression and pain catastrophizing were tested as potential mediators of treatment effects. Significant treatment improvements were found for functional disability, depression, pain catastrophizing, and perceived pain intensity but with no differences between groups. Improvements in depressed mood, pain catastrophizing (helplessness subscale), and pain severity partially mediated functioning improvement. Pain severity was not a significant mediator in the CP + POTS group. We concluded that depression and pain catastrophizing, especially the helplessness domain, can impact functioning improvement in adolescents with CP and POTS and are particularly important to target in treatment.