Accepted

Little is known about the link between pathophysiologic factors and symptoms of irritable bowel syndrome (IBS), or whether these factors have cumulative effects on patient-reported outcomes (PROs). We investigated whether pathophysiologic alterations associated with IBS have cumulative or independent effects on PROs.

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.

Native Americans (NAs) have a higher prevalence of chronic pain than any other U.S. racial/ethnic group; however, little is known about the mechanisms for this pain disparity. This study used quantitative sensory testing (QST) to assess pain experience in healthy, pain-free adults (N=137 NAs [87 female], N=145 non-Hispanic whites [NHW; 68 female]) following painful electric, heat, cold, ischemic, and pressure stimuli. Following each stimulus, ratings of pain intensity, sensory pain, affective pain, pain-related anxiety, and situation-specific pain catastrophizing were assessed. Results suggested that NAs reported greater sensory pain in response to suprathreshold electric and heat stimuli, greater pain-related anxiety to heat and ischemic stimuli, and more catastrophic thoughts in response to electric and heat stimuli. Sex differences were also noted; however, with the exception of catastrophic thoughts to cold, these were not moderated by race/ethnicity. Together, findings suggest NAs experience heightened sensory, anxiety, and catastrophizing reactions to painful stimuli. This could place NAs at risk for future chronic pain and could ultimately lead to a vicious cycle that maintains pain (e.g., pain→anxiety/catastrophizing→pain). PERSPECTIVE: Native Americans experienced heightened sensory, anxiety, and catastrophizing reactions in response to multiple pain stimuli. Given the potential for anxiety and catastrophic thoughts to amplify pain, this may place them at risk for pain disorders and could lead to a vicious cycle that maintains pain.