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Common and distinct neural representations of aversive somatic and visceral stimulation in healthy individuals.

Different pain types may be encoded in different brain circuits. Here, we examine similarities and differences in brain processing of visceral and somatic pain. We analyze data from seven fMRI studies (N = 165) and five types of pain and discomfort (esophageal, gastric, and rectal distension, cutaneous thermal stimulation, and vulvar pressure) to establish and validate generalizable pain representations. We first evaluate an established multivariate brain measure, the Neurologic Pain Signature (NPS), as a common nociceptive pain system across pain types. Then, we develop a multivariate classifier to distinguish visceral from somatic pain. The NPS responds robustly in 98% of participants across pain types, correlates with perceived intensity of visceral pain and discomfort, and shows specificity to pain when compared with cognitive and affective conditions from twelve additional studies (N = 180). Pre-defined signatures for non-pain negative affect do not respond to visceral pain. The visceral versus the somatic classifier reliably distinguishes somatic (thermal) from visceral (rectal) stimulation in both cross-validation and independent cohorts. Other pain types reflect mixtures of somatic and visceral patterns. These results validate the NPS as measuring a common core nociceptive pain system across pain types, and provide a new classifier for visceral versus somatic pain.

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Time Between an Emergency Department Visit and Initiation of Physical Therapist Intervention: Health Care Utilization and Costs.

The aim of this study was to examine the association between the length of time between an emergency department (ED) visit and the subsequent initiation of physical therapist intervention for low back pain (LBP) on 1-year LBP-related health care utilization (ie, surgery, advanced imaging, injections, long-term opioid use, ED visits) and costs.

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Associations of Psychologic Factors with Multiple Chronic Overlapping Pain Conditions.

To characterize psychologic functioning across five chronic overlapping pain conditions (COPCs)-temporomandibular disorders, fibromyalgia, low back pain, headache, and irritable bowel syndrome-and their overlaps.

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A Secondary Analysis from a Randomized Trial on the Effect of Plasma Tetrahydrocannabinol Levels on Pain Reduction in Painful Diabetic Peripheral Neuropathy.

This report examines the association between tetrahydrocannabinol (THC) plasma levels and pain response in a secondary analysis of data from a recent diabetic neuropathy study that demonstrated a dose-dependent reduction in spontaneous and elicited pain at specific time points. A randomized, double-blinded, placebo-controlled crossover study was conducted in sixteen patients with painful diabetic peripheral neuropathy. Subjects participated in four sessions, separated by 2 weeks, during each of which they were exposed to one of four conditions: placebo, or 1%, 4%, or 7% THC dose of cannabis. Baseline assessments of spontaneous and evoked pain were performed. Subjects were then administered aerosolized cannabis or placebo and pain intensity and cognitive testing at specific time points for 4 hours. A blood sample was drawn from the left antecubital vein for plasma assay of total THC at 0, 15, 30, 45, 60, 150, and 240 minutes. Associations were made between pain intensity, cognitive impairment and THC plasma levels in this secondary analysis. Results suggested a U-shaped relation whereby pain ratings are greatest at extreme (low and high) levels of THC. The therapeutic window appeared to fall between 16 ng/mL and 31 ng/mL THC plasma level. There was a significant linear effect of THC on only one out of the three cognitive tests. These findings stress the importance of measuring cannabinoid plasma levels when performing future research. Perspective: This analysis correlating plasma THC levels and pain reduction in diabetic neuropathy suggest a therapeutic window. Low and high THC levels had a negative association (no reduction) and THC levels within the window had a positive association (reduction). There was a minor negative linear effect of THC on cognitive function.

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Psychosocial Mechanisms of Cognitive-Behavioral-Based Physical Therapy Outcomes After Spine Surgery: Preliminary Findings From Mediation Analyses.

Changing Behavior through Physical Therapy (CBPT), a cognitive-behavioral-based program, has been shown to improve outcomes after lumbar spine surgery in patients with a high psychosocial risk profile; however, little is known about potential mechanisms associated with CBPT treatment effects. The purpose of this study was to explore potential mediators underlying CBPT efficacy after spine surgery.

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Prevalence and predictors of chronic pain intensity and disability among adults with sickle cell disease.

Among 170 adults with sickle cell disease, we evaluated chronic pain impact and disability prevalence, assessed age and gender differences, and identified psychosocial predictors of chronic pain intensity and disability. Most participants had a high level of disability. Chronic pain intensity and disability were significantly associated with pain catastrophizing and chronic pain self-efficacy, and worsened with age. Further research is needed to confirm study findings and develop interventions, including palliative care approaches that address catastrophizing and disability, particularly for young women and middle-aged adults with sickle cell disease. Moreover, consistent clinical assessment of chronic pain and psychosocial health should be implemented.

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Opioid cessation and chronic pain: perspectives of former opioid users.

Current guidelines for addressing opioid cessation in the context of chronic pain management recommend that opioids be discontinued if the risks outweigh the benefits. However, few studies have focused on understanding opioid cessation from the perspective of individuals with chronic pain. This mixed-method study included 49 former opioid users with chronic pain and used quantitative survey data and qualitative focus group data to identify themes pertaining to former opioid user's experience before, during, and after opioid cessation. Participants described several reasons for wanting to stop opioids including lack of efficacy, impact on quality of life, and concerns about addiction. Barriers to cessation included concerns about inadequate pain management and concerns about the impact of stopping opioids on mood. After opioid cessation, the sample was mixed regarding the benefit of cessation. Half of the former opioid users reported their pain to be better or the same after stopping opioids; however, 47% of the sample reported feeling worse pain since stopping their opioids. As the pendulum swings from pain control to drug control, we must ensure that the response to the opioid epidemic does not cause harm to individuals with chronic pain. Novel opioid cessation interventions are needed in combination with methods of addressing individual challenges and barriers to adequate pain relief including access to and provision of nonopioid alternatives for pain management.

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Childhood Trauma Predicts Cancer Treatment-Related Pain in Breast Cancer Survivors.

Childhood trauma has been linked to neuropathic pain in noncancer populations, but its relationship with cancer treatment-related neuropathic pain is unknown.

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Moderators of mindfulness meditation, cognitive therapy, and mindfulness-based cognitive therapy for chronic low back pain: A test of the Limit, Activate and Enhance model.

This study examined psychosocial pain treatment moderation in a secondary analysis of a trial that compared cognitive therapy (CT), mindfulness-meditation (MM), and mindfulness-based cognitive therapy (MBCT) for chronic low back pain (CLBP). The Limit, Activate and Enhance (LA&E) model of moderation provided a framework for testing a priori hypotheses. Adult participants (N=69) with CLBP completed a pre-treatment assessment of hypothesized moderators: pain catastrophizing, brain state as assessed by electroencephalogram, mindful observing, and non-reactivity. Outcomes were pain interference, characteristic pain intensity, physical function, and depression, assessed at pre- and post-treatment. Moderation analyses found significant interaction effects, specifically: (1) higher and lower baseline pain catastrophizing was associated with greater improvement in pain intensity in MM and MBCT, respectively; (2) higher baseline theta power was associated with greater improvement in depression in MBCT and interfered with response to CT; (3) lower baseline non-reactivity was associated with greater improvement in physical function in MM while higher non-reactivity was associated with greater improvement in MBCT. The findings support the possibility that different patients are more or less likely to benefit from various treatments. Theory-driven moderation research has the capacity to inform the development of patient-treatment matching algorithms to optimize outcome. Perspective: This study presents preliminary findings from theory-driven tests of the moderators of mindfulness meditation, cognitive therapy and mindfulness-based cognitive therapy for chronic low back pain. The results of such analyses may inform the understanding of for whom various evidence-based psychosocial pain treatments may engender the most meaningful benefits.

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Physical therapy informed by Acceptance and Commitment Therapy (PACT) versus usual care physical therapy for adults with chronic low back pain: a randomised controlled trial.

Chronic low back pain (CLBP) is a major cause of global disability and improving management is essential. Acceptance and Commitment Therapy (ACT) is a promising treatment for chronic pain but has not been modified for physical therapy. This randomized controlled trial (RCT) compared physical therapy informed by Acceptance and Commitment Therapy (PACT) against standard care physical therapy for patients with CLBP. Patients with CLBP (duration ≥12 weeks, mean 3 years) were recruited from physical therapy clinics in four UK public hospitals. The Roland-Morris Disability Questionnaire (RMDQ) at 3 months' post randomization was the primary outcome. 248 participants (59% female, mean age=48) were recruited and 219 (88•3%) completed measures at 3 and/or 12 months' follow-up. At 3 months, PACT participants reported better outcomes for disability (RMDQ mean difference =1•07, p=0•037, 95%CI -2•08 to -0•07, d=0•2), Patient Specific Functioning (p=0.008), SF12 physical health (p=0.032), and treatment credibility (p<0.001). At 12 months' follow-up there were no significant differences between groups. PACT was acceptable to patients and clinicians and feasible to deliver. Physical therapists incorporated psychological principles successfully and treatment was delivered with high (≥80%) fidelity. Our results may inform the management of CLBP, with potential benefits for patients, health care providers and society. PERSPECTIVE: Psychologically informed physical therapy has great potential but there are challenges in implementation. The training and support included in the PACT trial enabled the intervention to be delivered as planned. This successfully reduced disability in the short but not long term. Findings could inform physical therapists' treatment of CLBP.

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