Internet-delivered interventions hold the possibility to make pain rehabilitation more accessible and adaptable by providing qualified individualized psychological care to chronic pain patients in their homes. Acceptance and commitment therapy (ACT) has shown promising results on psychological functioning and pain acceptance. Internet-delivered ACT (IACT) added to multimodal pain rehabilitation program (MMRP) in primary care has, so far, not shown better results than MMRP alone. The aim of this cluster randomized controlled study was to investigate the effects of adding IACT during and after MMRP in specialist care on psychological outcomes. In total, 122 patients who enrolled in a specialist pain clinic were cluster randomized groupwise to either MMRP (n = 12 groups) or to MMRP with added IACT (n = 12 groups). The IACT addition included 6 weeks of treatment during MMRP and 11 weeks of aftercare following MMRP. Online and paper-and-pencil self-report measures of pain acceptance, psychological inflexibility, self-efficacy, and psychosocial consequences of pain, were collected at four occasions: prior to and post MMRP, post aftercare intervention and at 1 year follow-up. Dropout was extensive with 25% dropping out at post treatment, an additional 35% at post aftercare, and 29% at 1 year follow-up. Medium treatment between-group effects were found on pain acceptance in favor of the group who received IACT added to MMRP, at post treatment and at post aftercare. Large effects were seen on psychological inflexibility and self-efficacy at post aftercare. A medium effect size was seen on affective distress at post aftercare. Moreover, a medium effect on self-efficacy was found at 1 year follow-up. The results indicate that IACT added during MMRP may enhance the treatment effects on pain-related psychological outcomes. Results also suggest that IACT as aftercare may strengthen the long-term effect of MMRP. However, adding a second pain treatment, IACT, to an already extensive pain treatment, MMRP, could be perceived as too comprehensive and might hence influence completion negatively. Further research on adverse events and negative effects could be helpful to improve adherence. Next step of implementation trials could focus on adding IACT before MMRP to improve psychological functioning and after MMRP to prolong its effect.

Objectives: We recently developed a transdiagnostic exposure treatment (the hybrid treatment) for chronic pain patients with concurrent emotional difficulties. This paper investigates the hypothesized treatment processes, specifically: (1) if changes on pain-related dysregulation (catastrophizing, fear-avoidance, and nonacceptance of pain) and general emotion dysregulation (difficulties to regulate a broad spectrum of emotional responses) mediate effects on outcomes; and (2) if mediation is more pronounced for patients who score higher on these processes pretreatment. Materials and Methods: Structural equation modeling for longitudinal data using the full intention-to-treat sample was used to test whether proposed variables mediated the effect of the hybrid treatment (n=58) compared with a guided internet-delivered pain management treatment based on cognitive-behavioral principles (n=57) on pain interference and depressive symptoms at the 9-month follow-up. To make full use of the multiple process measures collected in the trial, we modeled mediators as 2 continuous latent variables: pain-related dysregulation and general emotion dysregulation. Results: Reduced pain-related dysregulation mediated the effects of treatment on both outcomes, whereas reduced general emotion dysregulation mediated the effects on depressive symptoms only. In the hybrid treatment, the mediated effect was more pronounced for participants who scored higher on pain-related dysregulation pretreatment relative to those who scored lower. Discussion: Our findings provide initial support for the transdiagnostic theoretical underpinnings of the hybrid treatment model. Using a hybrid treatment approach that centers on teaching patients emotion-regulation skills before commencing broad exposure successfully influenced both pain-related dysregulation and general emotion dysregulation, which in turn was associated with better treatment outcomes. It appears central to address these processes in pain patients with comorbid emotional problems, especially among patients scoring high on measures of catastrophizing, fear-avoidance, and nonacceptance of pain.

Purpose: The remodeling of functional neuronal connectivity in chronic widespread pain (CWP) patients remains largely unexplored. This study aimed to investigate functional connectivity in CWP patients in brain networks related to chronic pain for changes related to pain sensitivity, psychological strain, and experienced pain.

Patients and methods: Functional connectivity strength of the default mode network (DMN) and the salience network (SN) was assessed with functional magnetic resonance imaging. Between-group differences were investigated with an independent component analysis for altered connectivity within the whole DMN and SN. Then, changes in connectivity between nodes of the DMN and SN were investigated with the use of a seed-target analysis in relation to the covariates clinical pain intensity, pressure pain sensitivity, psychological strain, and as an effect of experienced experimental cuff-pressure pain.

Results: CWP patients showed decreased connectivity in the inferior posterior cingulate cortex (PCC) in the DMN and increased connectivity in the left anterior insula/superior temporal gyrus in the SN when compared to controls. Moreover, higher pain sensitivity in CWP when compared to controls was related to increased connectivity within the SN (between left and right insula) and between SN and DMN (between right insula and left lateral parietal cortex).

Conclusion: This study shows that connectivity within the DMN was decreased and connectivity within the SN was increased for CWP. Furthermore, we present a novel finding of interaction of pain sensitivity with SN and DMN-SN functional connectivity in CWP.

The comorbidity between chronic pain and emotional problems has proven difficult to address with current treatment options. This study addresses the efficacy of a transdiagnostic emotion-focused exposure treatment ("hybrid") for chronic pain patients with comorbid emotional problems. Adults (n = 115) with chronic musculoskeletal pain and functional and emotional problems were included in a 2-centre, parallel randomized controlled, open-label trial comparing this treatment to an active control condition receiving a guided Internet-delivered pain management treatment based on CBT principles (iCBT). The hybrid treatment (n = 58, 10-16 sessions) integrates exposure in vivo for chronic pain based on the fear-avoidance model with an emotion-regulation approach informed by procedures in Dialectical Behavior Therapy. The iCBT (n = 57; 8 treatment modules) addresses topics such as pain education, coping strategies, relaxation, problem solving, stress, and sleep management using standard CBT techniques. Patient-reported outcomes were assessed before and after treatment as well as at a 9-month primary end point. Across conditions, 78% participants completed post-treatment and 81% follow-up assessment. Intent-to-treat analyses showed that the hybrid had a significantly better post-treatment outcome on pain catastrophizing (d = 0.39) and pain interference (d = 0.63) and significantly better follow-up outcomes on depression (d = 0.43) and pain interference (d = 0.51). There were no differences on anxiety and pain intensity. Observed proportions of clinically significant improvement favoured the hybrid on all but one comparison, but no statistically significant differences were observed. We conclude that the hybrid emotion-focused treatment may be considered an acceptable, credible, and efficacious treatment option for chronic pain patients with comorbid emotional problems.