When pain gets stuck: the evolution of pain chronification and treatment resistance

The impact of emotional distress on response to radiofrequency ablation

Introduction

Radiofrequency ablation (RFA) is commonly performed for facet-mediated cervical, thoracic, and lumbar spine pain. Inadequate relief from RFA may be because of biopsychosocial factors not addressed with RFA.

Objectives

To investigate the effects of baseline emotional distress on RFA treatment response.

Methods

Patients who completed self-reported surveys, Patient-Reported Outcomes Measurement System (PROMIS), from January 2021 through July 2023 were included. Additional baseline information was obtained by retrospective review. The primary outcome was PROMIS Pain Intensity T-scores at 6 weeks, 3 months, and 6 months after RFA. The main predictor of interest was emotional distress, computed as average baseline PROMIS T-scores for depression and anxiety. Interaction terms tested how the influence of baseline emotional distress and pain intensity changed over the follow-up period.

Results

Data were available for 154, 101, 91, and 83 participants at baseline, 6 weeks, 3 months, and 6 months post-RFA, respectively. Baseline emotional distress (P = 0.04) and baseline pain intensity (P = 0.01) were both associated with worse pain intensity at follow-up, controlling for each other. Interaction terms were not significant, though visual inspection of trends suggested that the influence of baseline emotional distress may increase as the follow-up period lengthens.

Conclusion

Patients reporting higher levels of baseline emotional distress experience less pain reduction after RFA, controlling for baseline pain intensity. Patients with greater emotional distress may benefit from treatments addressing emotional distress, in addition to or instead of RFA.

Subcutaneous Lidocaine Infusion for Chronic Widespread Pain: A Chart Review and Survey Examining the Safety and Tolerability of Treatment

Chronic widespread pain (CWP) is characterized by persistent pain across multiple body regions, often accompanied by fatigue, cognitive difficulties, and psychological distress. Background/Objectives: Affecting approximately 10% of the general population, CWP disproportionately impacts women, individuals from lower socioeconomic backgrounds, immigrants, and those with a family history of chronic pain. Standard treatments, including cognitive-behavioral therapy, exercise, and pharmacotherapy, often provide insufficient relief. This study explores a novel approach to treating treatment-resistant CWP: high-dose subcutaneous lidocaine infusions administered over extended periods. Methods: The research included a retrospective chart review and patient survey to evaluate safety and tolerability. The protocol started with a dose of 10-12 mg/kg of adjusted body weight, increasing by 10-15% per month, with a maximum dose of 2000 mg. Results: The chart review of 27 patients revealed mild to moderate adverse events (AEs) in seven patients, with no severe AEs. A survey of 15 patients indicated a higher incidence of AEs; however, all patients reported that the benefits outweighed the negatives. On average, patients experienced 61% pain relief, lasting 19 days per infusion. Conclusions: This study demonstrates that subcutaneous lidocaine infusions are a well-tolerated treatment for CWP, offering substantial pain relief and improving patients' quality of life.

Understanding the individual's transition from acute to chronic disabling pain: Opportunities for improved care

When acute pain persists, it is said to become chronic after 3 months. Considerable interest has focused on why acute pain appears to transition to chronic pain in some cases, but not all, especially when it becomes disabling. We examine our current understanding of the processes involved in the progression from an acute injury to disabling chronic pain. Rather than viewing this progression as a time dependent transition with specific static risk factors, we consider whether it might be more helpful to understand this evolution in terms of unique individual pathways. While brief self-report screening questionnaires assessing risk factors may enable us to stratify patients into risk levels, they do not provide information on the unique context and factors contributing to the disabling pain for each person. It is proposed that a 2-step process combining screening and individual assessment of those at high risk will enhance the prospect of both early identification and individually relevant interventions before more lasting changes emerge. Rather than being concerned with arbitrary time limits, it is argued that by aiming to understand the unique developmental pathway for those individuals identified as high risk, early, preventive interventions will be both viable and effective. Even so, there are barriers to the implementation of early assessment and matched treatments, and these remain a challenge for future research.

The effect of expectancy on conditioned pain modulation: evidence from functional near-infrared spectroscopy

Background and objective

The psychological mechanisms that make Conditioned Pain Modulation (CPM) an effective non-pharmacological intervention are still not fully understood. Expectancy is believed to be a critical psychological factor affecting CPM effects, but its specific role has yet to be fully clarified. This study aims to explore the relationship between expectancy and CPM while providing physiological evidence using functional near-infrared spectroscopy (fNIRS).

Method

A standardized CPM induction paradigm was implemented, with verbal guidance used to induce expectancy. The Numeric Rating Scale (NRS) assessed the intensity of the test stimulus (TS), while an 11-point scale evaluated participants' attentional focus on the TS and the effect of expectancy. fNIRS was employed to monitor changes in prefrontal cortex (PFC) activity.

Results

Expectancy significantly amplified the CPM effect (p = 0.036) while markedly reducing attention to the experimental stimulus (p = 0.004). fNIRS findings indicated significant reductions in activity within the left frontal eye field, left dorsolateral prefrontal cortex, and left frontal pole regions. In the post-test, the control group demonstrated significantly higher cortical activity in the right frontal pole region compared to the expectancy group (p < 0.05). Within the expectancy group, bilateral frontal pole cortical activity was significantly lower in the post-test compared to the pre-test (p < 0.05).

Conclusion

Expectancy represents a key psychological mechanism underlying the CPM effect, potentially modulating its magnitude through attention regulation and accompanied by a reduction in oxygenated hemoglobin activity in the frontal pole region and introduced the Expectancy-Attention-CPM Modulation Model (ECAM).

Prolonged post-operative hydrocodone usage due to psychotropic drug interaction

OBJECTIVES

To explore pain outcomes in patients prescribed hydrocodone and psychotropic medications with or without CYP2D6 inhibition activity.

METHODS

Patients hospitalized for lower/limited upper extremity injuries who were prescribed hydrocodone alongside a psychotropic medication were considered for this study (n=224). A subset of these patients (n=178) was prescribed a psychotropic medication known to inhibit CYP2D6, while the remainder (n=46) were prescribed psychotropic medications without CYP2D6 inhibition activity. Patient demographics and pain outcomes were collected by electronic health record review and interviews.

RESULTS

Patients taking a psychotropic inhibitor of CYP2D6 exhibited longer duration of opioid use post-discharge (median 33 days [IQR 10-99]) compared with patients taking a psychotropic non-inhibitor (4 days [2-20], p<0.001). No significant differences were observed with in-hospital pain outcomes, including total dose of hydrocodone administered, duration of hydrocodone use, pain index scores, and the occurrence of common mild/moderate/severe hydrocodone side effects.

CONCLUSIONS

Patients prescribed at least one psychotropic inhibitor of CYP2D6 were more likely to continue using hydrocodone for up to 3 months following surgery. Knowledge of these critical drug-drug interactions could enhance clinical practice and improve patient outcomes. This study highlights negative post-operative pain outcomes in patients prescribed hydrocodone alongside a psychotropic inhibitor of CYP2D6. The results of this study indicate that patients taking psychotropic medications that inhibit CYP2D6 are at increased risk for prolonged hydrocodone use following orthopedic surgery.

Cortical reorganization in neuropathic pain due to peripheral nerve degeneration: altered cortical surface morphometry and hierarchical topography

ABSTRACT

Degeneration of peripheral nerves causes neuropathic pain. Previous studies have documented structural and functional brain alterations in peripheral neuropathy, which may be attributed to maladaptive plasticity following chronic neuropathic pain. Nevertheless, the effects of peripheral neuropathic pain on the macroscale organization of the cerebral cortex have not been explored. This study investigated altered surface morphology and topographic hierarchy of the cerebral cortex in patients with neuropathic pain due to peripheral neuropathy. T1-weighted magnetic resonance imaging data were acquired from 52 patients with peripheral neuropathic pain and 50 age- and sex-matched healthy controls. Cortical morphometric features including thickness and gyrification index were obtained using surface-based morphometry. A topographic gradient encoding interregional similarity in cortical thickness was extracted using a machine-learning technique named diffusion map embedding. Compared with controls, patients with neuropathic pain exhibited cortical thinning in the frontal and sensorimotor cortices, with the severity increasing with greater neuropathic pain. The patients also showed decreased gyrification in the insula, with a greater reduction in gyrification linked to more severe skin nerve degeneration. Moreover, the patients exhibited altered topographic organization of the cerebral cortex, where the direction of the topographic gradient deviated from the occipital-to-frontal axis observed in the controls in this study and reported in the literature. Our findings provided a novel perspective for macroscale cortical structural reorganization after neuropathic pain, showing thinning and gyral flattening in pain-related areas and deviation from the normal topographic axis of the cerebral cortex.

Advancements and prospects of transcranial focused ultrasound in pain neuromodulation

ABSTRACT

Transcranial focused ultrasound (tFUS) is an emerging noninvasive neuromodulation technology that has shown great potential in pain modulation. This review systematically elucidates the multilevel biological mechanisms of tFUS neuromodulation, from network-wide effects to cellular and molecular processes, as well as broader systemic influences. Preliminary animal pain model studies have revealed tFUS's ability to improve pain behavioral indicators and modulate neural circuit activity under pathological conditions. A small number of clinical studies also suggest that tFUS may have certain benefits in improving symptom experience and emotional state in chronic pain patients. However, current research generally has limitations such as small sample sizes and short follow-up periods. More high-quality studies are needed to verify the long-term effects and safety of tFUS pain treatment. Overcoming these limitations and advancing large-scale clinical translational research will help fully exploit the application potential of tFUS in precision pain medicine and provide new treatment options for pain relief.

A high fat, high sugar diet exacerbates persistent post-surgical pain and modifies the brain-microbiota-gut axis in adolescent rats

Persistent post-surgical pain (PPSP) occurs in a proportion of patients following surgical interventions. Research suggests that specific microbiome components are important for brain development and function, with recent studies demonstrating that chronic pain results in changes to the microbiome. Consumption of a high fat, high sugar (HFHS) diet can drastically alter composition of the microbiome and is a modifiable risk factor for many neuroinflammatory conditions. Therefore, we investigated how daily consumption of a HFHS diet modified the development of PPSP, brain structure and function, and the microbiome. In addition, we identified significant correlations between the microbiome and brain in animals with PPSP. Male and female rats were maintained on a control or HFHS diet. Animals were further allocated to a sham or surgery on postnatal day (p) p35. The von Frey task measured mechanical nociceptive sensitivity at a chronic timepoint (p65-67). Between p68-72 rats underwent in-vivo MRI to examine brain volume and diffusivity. At p73 fecal samples were used for downstream 16 s rRNA sequencing. Spearman correlation analyses were performed between individual microbial abundance and MRI diffusivity to determine if specific bacterial species were associated with PPSP-induced brain changes. We found that consumption of a HFHS diet exacerbated PPSP in adolescents. The HFHS diet reduced overall brain volume and increased white and grey matter density. The HFHS diet interacted with the surgical intervention to modify diffusivity in numerous brain regions which were associated with specific changes to the microbiome. These findings demonstrate that premorbid characteristics can influence the development of PPSP and advance our understanding of the contribution that the microbiome has on function of the brain-microbiota-gut axis.

Patient preferences for conservative treatment of shoulder pain: a discrete choice experiment

BACKGROUND

Shoulder pain is common amongst adults, but little is known about patients' preferences.

OBJECTIVE

The aim of this study was to determine patients' preferences for treatment options offered for shoulder pain in primary care.

METHODS

A discrete choice experiment was used to investigate these preferences. Adults with shoulder pain were asked to make 12 choices between two treatment options, or to opt-out. The attributes of the 12 treatment options were presented as varying in: treatment effectiveness (50%, 70%, or 90%), risk of relapse (10%, 20%, or 30%), time to pain reduction (2 or 6 weeks), prevention of relapse (yes/no), requiring injection (yes/no), and including physiotherapy (none, 6, or 12 sessions). A conditional logit model with latent class analysis was used for the analysis and a class assignment model.

RESULTS

Three hundred and twelve participants completed the questionnaire with mean age of 52 ± 15.2 years. Latent class analysis revealed three groups. Group 1 preferred to opt-out, unless the attributes were highly favorable (90% effectiveness). Group 2 preferred treatment, but not an injection. Group 3 preferred to opt-out and did not opt for treatment. The likelihood of a participant belonging to one of these groups was 68.8%, 9.3%, and 21.9%, respectively. The class assignment was related to having previously received injection or physiotherapy, as they did not prefer that same treatment again.

CONCLUSION

This study showed that most patients with shoulder pain prefer to opt-out, unless treatment attributes are highly favorable. Characteristics of influence on this decision was whether the patient had received an injection or physiotherapy before.

Integrating Physical Therapy and Virtual Reality to Manage Pain-Related Fear of Movement in Patients With Chronic Pain: A Randomized Controlled Trial

OBJECTIVES

This study aims to investigate the effect of virtual reality (VR) technology and physical therapy on pain-related fear of movement in patients with chronic pain.

METHODS

This randomized controlled trial included 73 patients with chronic pain. All participants underwent measurements using the Tampa Scale for Kinesiophobia (TSK), the Japanese version of the World Health Organization Health and Work Performance Questionnaire (WHO-HPQ), the Pain Self-Efficacy Questionnaire (PSEQ), the Numerical Rating Scale (NRS), the Hospital Anxiety and Depression Scale (HADS), the Pain Catastrophizing Scale (PCS), the International Physical Activity Questionnaire (IPAQ), the EuroQOL 5 Dimensions 5-Level (EQ-5D-5L), quadriceps muscle strength, the Timed Up and Go test (TUG), and the 30-s Chair Stand test (CS-30). The intervention group underwent three months of rehabilitation, incorporating VR and exercises administered by a physical therapist. The control group performed similar exercises guided by a physical therapist, with the only distinction being the absence of VR.

RESULTS

Sixty-six participants (32 males, mean age: 54.7±11.7 years) were included in the analysis. TSK scores improved at one-month post-intervention in the intervention group (ΔTSK: -12.4±2.1) compared to the control group (ΔTSK: -7.8±1.4) (p<0.05). The intervention group predominantly demonstrated improved TSK scores at one-month post-intervention. Multivariate logistic regression analysis at one-month post-intervention revealed significant associations between TSK scores and the intervention, PCS, PSEQ, and IPAQ scores (p<0.05).

DISCUSSION

This study revealed two significant findings: (i) combining physical therapy with VR effectively reduced pain-related fear of movement in patients at an early stage, and (ii) a change in the kinesiophobia scores in patients with chronic pain was associated with a change in pain catastrophizing, self-efficacy, and VR intervention. TSK scores in the intervention group significantly improved at one-month post-intervention compared to those in the control group. Combining VR with physical therapy effectively mitigated the excessive pain-related fear of movement. In this study, VR provided an exercise experience without physical pain for patients with chronic pain. This was intended to create a calming, distracting environment and thereby reduce the perceived threat of kinesiophobia. Furthermore, it is possible that there was a reduction in central sensitization. Multiple regression analysis revealed that ΔPCS, ΔPSEQ, and intervention were common elements of ΔTSK at one and three months post-intervention. These findings suggest that combined physical therapy with VR and improved PCS and PSEQ scores contributed to improved TSK scores. Therefore, VR could be beneficial in managing pain-related fear of movement by creating the illusion that exercise does not cause pain. This study had several limitations. First, pain assessment was subjective using questionnaires. Second, participants were limited to patients who underwent physical therapy, which may introduce selection bias. Third, findings were derived from a single pain clinic.

CONCLUSION

This study's findings indicated significant differences between the control and intervention groups, which combined physical therapy with VR, particularly in reducing pain-related fear of movement at an early stage.

Pain and Perception: Exploring Psychedelics as Novel Therapeutic Agents in Chronic Pain Management

PURPOSE OF REVIEW

Chronic pain affects approximately 1.5 billion people worldwide, representing the leading cause of disability and a significant financial burden on healthcare systems. Conventional treatments, such as opioids and non-steroidal anti-inflammatory drugs, are frequently linked to adverse effects, including dependency and gastrointestinal issues, and often offer limited long-term relief. This review explores the potential of psychedelics, including psilocybin, LSD, and ketamine, as alternative therapeutic agents in chronic pain management.

RECENT FINDINGS

These substances modulate pain perception through actions on serotonergic and glutamatergic systems and may promote neuroplasticity, offering novel pathways for pain relief. Specifically, the review details the pharmacologic actions of psychedelics, their effects on chronic pain syndromes such as cancer pain, migraines, and neuropathic pain, and their clinical implications. The safety profiles, patient responses, and analgesic properties of these compounds are examined, highlighting the need for further research to validate their efficacy and optimize their therapeutic use in pain management.

Patients With Chronic Pain: The Aspect Of Negative Body Image

OBJECTIVE

Negative body image is an increasingly important factor in chronic pain disorders; particularly because the two conditions mutually influence each other. Our study examines body-image-related attitudes and comorbid psychic symptoms in patients with chronic pain disorders.

METHODS AND MEASURES

188 patients with chronic pain answered the Dresden body image questionnaire (DKB-35), the Hospital Anxiety and Depression Scale (HADS) and the Beck's Depression Inventory (BDI).

RESULTS

The mean values of the DKB-35 subscales range between 2.24 und 3.29. The subscale "vitality" has the lowest mean value. BDI and HADS correlated significantly with the DKB-35 subscales. The subscale "body-acceptance" intercorrelated high with the two subscales "vitality" and "self-aggrandizement".

CONCLUSION

Our findings verify that chronic pain is strongly associated with negative body image. The issues of vitality and psychological symptoms seem particularly central in this complex interaction. The biopsycho-social model and the avoidance-endurance approach to chronic pain offer important ideas for explanation and treatment.

Chronic Pain Psychology in Neurology Practice

OBJECTIVE

This article reviews the latest literature regarding chronic pain epidemiology and describes pain-specific psychological factors associated with the development and maintenance of chronic pain, mental health conditions that co-occur with chronic pain, and advances in the psychobehavioral treatment of chronic pain, including established treatments (ie, cognitive behavioral therapy [CBT], acceptance and commitment therapy, and mindfulness-based stress reduction) and emerging treatments (ie, pain reprocessing therapy).

LATEST DEVELOPMENTS

In addition to CBT and acceptance and commitment therapy for pain, numerous other psychological treatment modalities have been integrated into chronic pain management, including mindfulness-based stress reduction, mindfulness meditation, chronic pain self-management, relaxation response, pain neuroscience education, biofeedback, hypnosis, and, more recently, integrative psychological treatment for centralized pain. This article gives an overview of these methods and contextualizes their use within the standard psychological treatment of chronic pain.

ESSENTIAL POINTS

Guided by the biopsychosocial treatment model, pain psychologists use numerous evidence-based psychological methods to treat patients with chronic pain conditions. Familiarity with the psychological tools available for pain management will aid neurologists and their patients in navigating the psychological aspects of living with chronic pain.

Rehabilitation to Improve Outcomes after Cervical Spine Surgery: Narrative Review

PURPOSE

The increasing elderly patient population is contributing to the rising worldwide load of cervical spinal disorders, which is expected to result in a global increase in the number of surgical procedures in the foreseeable future. Cervical rehabilitation plays a crucial role in optimal recovery after cervical spine surgeries. Nevertheless, there is no agreement in the existing research regarding the most suitable postsurgical rehabilitation program. Consequently, this review assesses the ideal rehabilitation approach for adult patients following cervical spine operations.

MATERIALS AND METHODS

This review covers activities of daily living and encompasses diverse treatment methods, including physiotherapy, specialized tools, and guidance for everyday activities. The review is organized under three headings: (1) historical perspectives, (2) patient-reported functional outcomes, and (3) general and disease-specific rehabilitation.

RESULTS

Rehabilitation programs are determined on the basis of patient-reported outcomes, performance tests, and disease prognosis. CSM requires strengthening of the neck and shoulder muscles that have been surgically invaded. In contrast, the CCI requires mobility according to the severity of the spinal cord injury and functional prognosis. The goal of rehabilitation for CCTs, as for CCIs, is to achieve ambulation, but the prognosis and impact of cancer treatment must be considered.

CONCLUSIONS

Rehabilitation of the cervical spine after surgery is essential for improving physical function and the ability to perform daily activities and enhancing overall quality of life. The rehabilitation process should encompass general as well as disease-specific exercises. While current rehabilitation protocols heavily focus on strengthening muscles, they often neglect the crucial aspect of spinal balance. Therefore, giving equal attention to muscle reinforcement and the enhancement of spinal balance following surgery on the cervical spine is vital.

Virtual Reality for Subacute Pain After Orthopedic Traumatic Musculoskeletal Injuries: A Mixed Methods Pilot Study

OBJECTIVES

Acute orthopedic traumatic musculoskeletal injuries are prevalent, costly, and often lead to persistent pain and functional limitations. Psychological risk factors (eg, pain catastrophizing and anxiety) exacerbate these outcomes but are often overlooked in acute orthopedic care. Addressing gaps in current treatment approaches, this mixed-methods pilot study explored the use of a therapeutic virtual reality (VR; RelieVRx ), integrating principles of mindfulness and cognitive-behavioral therapy, for pain self-management at home following orthopedic injury.

METHODS

We enrolled 10 adults with acute orthopedic injuries and elevated pain catastrophizing or pain anxiety from Level 1 Trauma Clinics within the Mass General Brigham health care system. Participants completed daily RelieVRx sessions at home for 8 weeks, which included pain education, relaxation, mindfulness, games, and dynamic breathing biofeedback. Primary outcomes were a priori feasibility, appropriateness, acceptability, satisfaction, and safety. Secondary outcomes were pre-post measures of pain, physical function, sleep, depression, and hypothesized mechanisms (pain self-efficacy, mindfulness, and coping).

RESULTS

The VR and study procedures met or exceeded all benchmarks. We observed preliminary improvements in pain, physical functioning, sleep, depression, and mechanisms. Qualitative exit interviews confirmed high satisfaction with RelieVRx and yielded recommendations for promoting VR-based trials with orthopedic patients.

DISCUSSION

The results support a larger randomized clinical trial of RelieVRx versus a sham placebo control to replicate the findings and explore mechanisms. There is potential for self-guided VR to promote evidence-based pain management strategies and address the critical mental health care gap for patients following acute orthopedic injuries.

Resting-state frontal electroencephalography (EEG) biomarkers for detecting the severity of chronic neuropathic pain

Increasing evidence is present to enable pain measurement by using frontal channel EEG-based signals with spectral analysis and phase-amplitude coupling. To identify frontal channel EEG-based biomarkers for quantifying pain severity, we investigated band-power features to more complex features and employed various machine learning algorithms to assess the viability of these features. We utilized a public EEG dataset obtained from 36 patients with chronic pain during an eyes-open resting state and performed correlation analysis between clinically labelled pain scores and EEG features from Fp1 and Fp2 channels (EEG band-powers, phase-amplitude couplings (PAC), and its asymmetry features). We also conducted regression analysis with various machine learning models to predict patients' pain intensity. All the possible feature sets combined with five machine learning models (Linear Regression, random forest and support vector regression with linear, non-linear and polynomial kernels) were intensively checked, and regression performances were measured by adjusted R-squared value. We found significant correlations between beta power asymmetry (r = -0.375), gamma power asymmetry (r = -0.433) and low beta to low gamma coupling (r = -0.397) with pain scores while band power features did not show meaningful results. In the regression analysis, Support Vector Regression with a polynomial kernel showed the best performance (R squared value = 0.655), enabling the regression of pain intensity within a clinically usable error range. We identified the four most selected features (gamma power asymmetry, PAC asymmetry of theta to low gamma, low beta to low/high gamma). This study addressed the importance of complex features such as asymmetry and phase-amplitude coupling in pain research and demonstrated the feasibility of objectively observing pain intensity using the frontal channel-based EEG, that are clinically crucial for early intervention.

Childhood Reading Ability and Pain in Childhood Through to Midlife

Dyslexia and pain have recently been shown to correlate on a genetic level, but there has been little exploration of this association on the phenotypic level despite reports of increased pain in Attention Deficit Hyperactivity Disorder, which commonly co-occurs with dyslexia. In this study we test for an association between reading ability, which is the primary feature of dyslexia, and pain both in childhood and adulthood. Logistic regression modeling was used to test associations between reading ability in childhood and pain from childhood to midlife in a large UK birth cohort; the 1958 National Child Development Study. Associations were found between poor childhood reading ability and increased headache and abdominal pain in childhood, and between poor childhood reading ability and headache, eye pain, back pain, and rheumatism in adulthood. Mediation analyses indicated that socioeconomic status (defined by employment) fully mediated the association between poor reading ability in childhood and back pain at age 42. By contrast, the association between reading ability and eye pain acted independently of socioeconomic status. Different mechanisms were thus indicated for the association of reading with different pain types, including manual labor and a potential shared biological pathway. PERSPECTIVE: This study found a relationship between poor reading ability in childhood and pain in childhood and adulthood. Those with reading difficulties should be monitored for pain symptoms. Future research may uncover shared biological mechanisms, increasing our understanding of pain and potential treatments.

Pain-Insomnia-Depression Syndrome: Triangular Relationships, Pathobiological Correlations, Current Treatment Modalities, and Future Direction

Pain-insomnia-depression syndrome (PIDS) is a complex triad of chronic pain, insomnia, and depression that has profound effects on an individual's quality of life and mental health. The pathobiological context of PIDS involves complex neurobiological and physiological mechanisms, including alterations in neurotransmitter systems and impaired pain processing pathways. The first-line therapeutic approaches for the treatment of chronic pain, depression, and insomnia are a combination of pharmacological and non-pharmacological therapies. In cases where patients do not respond adequately to these treatments, additional interventions such as deep brain stimulation (DBS) may be required. Despite advances in understanding and treatment, there are still gaps in knowledge that need to be addressed. To improve our understanding, future research should focus on conducting longitudinal studies to uncover temporal associations, identify biomarkers and genetic markers associated with PIDS, examine the influence of psychosocial factors on treatment responses, and develop innovative interventions that address the complex nature of PIDS. The aim of this study is to provide a comprehensive overview of these components and to discuss their underlying pathobiological relationships.

Biobehavioral Predictors of Pain Intensity, Pain Interference, and Chronic Pain Episodes: A Prospective Cohort Study of African-American Adults

Racial disparities in pain experiences are well-established, with African-American (AA) adults reporting higher rates of daily pain, increased pain severity, and greater pain-related interference compared to non-Hispanic Whites. However, the biobehavioral factors that predict the transition to chronic pain among AA adults are not well understood. This prospective cohort study provided a unique opportunity to evaluate predictors of chronic pain onset among 130 AA adults (81 women), ages 18 to 44, who did not report chronic pain at their baseline assessment and subsequently completed follow-up assessments at 6- and 12-months. Outcome measures included pain intensity, pain-related interference, and chronic pain status. Comprehensive assessments of sociodemographic and biobehavioral factors were used to evaluate demographics, socioeconomic status, stress exposure, psychosocial factors, prolonged hypothalamic-pituitary-adrenal secretion, and quantitative sensory testing responses. At baseline, 30 adults (23.1%) reported a history of prior chronic pain. Over the 12-month follow-up period, 13 adults (10.0%) developed a new chronic pain episode, and 18 adults (13.8%) developed a recurrent chronic pain episode. Whereas socioeconomic status measures (ie, annual income, education) predicted changes in pain intensity over the follow-up period, quantitative sensory testing measures (ie, pain threshold, temporal summation of pain) predicted changes in pain interference. A history of chronic pain and higher depressive symptoms at baseline independently predicted the onset of a new chronic pain episode. The present findings highlight distinct subsets of biobehavioral factors that are differentially associated with trajectories of pain intensity, pain-related interference, and onset of chronic pain episodes in AA adults. PERSPECTIVE: This prospective study sought to advance understanding of biobehavioral factors that predicted pain outcomes over a 12-month follow-up period among AA adults without chronic pain at their initial assessment. Findings revealed distinct subsets of factors that were differentially associated with pain intensity, pain-related interference, and onset of chronic pain episodes.

Interoceptive bodily awareness in patients seeking pain relief with osteopathic manipulative treatment: an observational cohort pilot study

CONTEXT

Interoceptive bodily awareness (IBA) is one's attentional focus on and relationship with comfortable and uncomfortable (e.g., pain) internal body sensations. Integrating IBA into research on osteopathic manipulative treatment (OMT) is growing, both as an outcome and predictor of treatment outcomes; however, it has yet to be studied in a clinical setting.

OBJECTIVES

We aimed to conduct a pilot study to measure IBA, with the Multidimensional Assessment of Interoceptive Awareness (MAIA), in patients seeking OMT for pain, and to test if OMT exposure may be associated with higher IBA as measured by the MAIA. The primary outcome was the change in MAIA scores, and the secondary outcomes were reduction in pain intensity, reduction in pain interference, and increase in participants' perception of change post-OMT.

METHODS

A convenience sample was recruited from individuals presenting for OMT appointments at a College of Osteopathic Medicine OMT teaching clinic. Participants were recruited into our single-arm observational cohort study (n=36), and categorized into one of two groups, OMT-naïve (n=19) or OMT-experienced (n=17), based on prior exposure to OMT. We measured MAIA scores and clinical pain-related outcomes prior to, immediately after, and at 1 and 3 weeks after a usual-care OMT session in the clinic. Covariates including experience with mind-body activities, non-OMT body work, and physical and emotional trauma were also collected to explore potential relationships. We utilized t tests to compare MAIA scores and pain outcomes between groups and across time points. Stepwise regression models were utilized to explore potential relationships with covariates.

RESULTS

The OMT-experienced group scored higher on the MAIA scales "Not-worrying" (p=0.002) and "Trusting" (p=0.028) at baseline. There were no significant changes in the MAIA scores before and after the single OMT session. Analysis of secondary outcomes revealed that all pain outcomes significantly decreased post-OMT (p<0.05), with the largest relative improvements in the acute pain and OMT-naïve subgroups, with diminishing effects over time.

CONCLUSIONS

Assessing IBA with MAIA in a clinical OMT setting is feasible. There were significant positive correlations between OMT exposure and two of the eight MAIA scales. Future studies are justified to further explore this relationship.

Effectiveness of a pain neuroscience education programme on the physical activity of patients with chronic low back pain compared with a standard back school programme: protocol for a randomised controlled study (END-LC)

INTRODUCTION

Education is recognised as an effective and necessary approach in chronic low back pain. Nevertheless, data regarding the effectiveness of education in promoting physical activity in the medium term or long term are still limited, as are the factors that could lead to successful outcomes. Our study aims to assess the effectiveness of a pain neuroscience education programme compared with traditional back school on physical activity 3 months and 1 year after educational sessions coupled with a multidisciplinary rehabilitation programme. Additionally, we seek to evaluate the effects of these educational interventions on various factors, including pain intensity and psychobehavioural factors. Finally, our goal is to identify the determinants of success in educational sessions combined with the rehabilitation programme.

METHODS AND ANALYSIS

The study will involve 82 adults with chronic low back pain. It will be a monocentric, open, controlled, randomised, superiority trial with two parallel arms: an experimental group, 'pain neuroscience education', and a control group, 'back school'. The primary outcome is the average number of steps taken at home over a week, measured by an actigraph. Secondary outcomes include behavioural assessments. Descriptive and inferential analysis will be conducted. Multivariate modelling will be performed using actimetric data and data from the primary and secondary outcomes.

ETHICS AND DISSEMINATION

The Committee for Personal Protection of Ile de France VII (CPP) gave a favourable opinion on 22 June 2023 (National number: 2023-A00346-39). The study was previously registered with the National Agency for the Safety of Medicines and Health Products (IDRCB: 2023-A00346-39). Participants signed an informed consent during the inclusion visit. This protocol is the version submitted to the CPP entitled 'Protocol Version N°1 of 03/29/2023'. The results of the study will be presented nationally and internationally through conferences and publications.

TRIAL REGISTRATION NUMBER

NCT05840302.

Childhood trauma and the use of opioids and other prescription analgesics in adolescence and young adulthood: The HUNT Study

ABSTRACT

Opioid and nonopioid analgesics are commonly prescribed to young people to alleviate pain. Even short-term prescriptions increase the risk of persistent use and future misuse of potent analgesics, such as opioids. Childhood trauma exposure has been found to be related to pain conditions and to using more prescription analgesics. This large, prospective cohort study aimed to investigate the association of a broad range of childhood trauma exposures with prescription rates for opioid and nonopioid analgesics in adolescence and young adulthood. Self-reported data on childhood trauma exposures from adolescents (aged 13-19 years) who participated in the Young-HUNT3 Study (2006-2008, n = 8199) were linked to data from the Norwegian Prescription Database (NorPD, 2004-2021). We found that exposure to childhood trauma was consistently associated with higher prescription rates for opioids throughout adolescence and young adulthood. The highest incidence rate ratio (IRR) in adolescence was observed for sexual abuse (IRR 1.63, confidence interval [CI] 1.19-2.23). In young adulthood, the highest IRR was observed for physical violence (2.66, CI 2.27-3.12). The same overall pattern was observed for nonopioid analgesics. The more frequent prescriptions of opioid and nonopioid analgesics to participants exposed to childhood trauma suggests a higher symptom load of pain causing them to seek professional help with pain relief. Receiving potent analgesics is not without risk, and the likelihood of misuse may be elevated among trauma-exposed individuals. A trauma-informed approach to pain could be vital for guiding clinicians to the most effective and least harmful treatment for each patient.

Experiences of patients with advanced cancer coping with chronic pain: a qualitative analysis

OBJECTIVES

To gain insight into the perceptions, and beliefs of patients with advanced cancer coping with chronic pain and to identify their attitudes and demands on pain management.

METHODS

From July to September 2022, 17 patients with advanced cancer living with chronic pain were recruited from a tertiary cancer hospital in Hunan Province, China. Qualitative and semi-structured interviews were conducted individually, with 30-45 minutes for each. The Colaizzi 7-step analysis method in phenomenological research was used for data analysis.

RESULTS

The experience of pain acceptance by advanced cancer patients with chronic pain was summarized into four themes: pain catastrophizing (unable to ignore the pain, try various methods to relieve the pain, exaggerating pain perception, and lack of knowledge about proper pain management), rumination (compulsive rumination and worrying rumination), avoidance coping (situational avoidance and repressive avoidance) and constructive action (setting clear value goal and taking reciprocal action).

CONCLUSION

Most patients with advanced cancer had low pain acceptance and negative attitudes. Feeling helpless in the face of pain and suffering alone were their norm. Long-term negative emotions could lead to gradual depression and loss of hope for treatment, resulting in pain catastrophizing and persistent rumination. Nevertheless, a few patients accepted pain with positive attitudes. Medical professionals should pay more attention to the psychological status of advanced cancer patients with chronic pain, and employ alternative therapies, for example, cognitive behavioral therapy. More efforts are needed to reduce patients' pain catastrophizing, and promote their pain acceptance by a better understanding of pain through health education.

Personality systems interactions theory: an integrative framework complementing the study of the motivational and volitional dynamics underlying adjustment to chronic pain

In the endeavor to advance our understanding of interindividual differences in dealing with chronic pain, numerous motivational theories have been invoked in the past decade. As they focus on relevant, yet different aspects of the dynamic, multilevel processes involved in human voluntary action control, research findings seem fragmented and inconsistent. Here we present Personality Systems Interactions theory as an integrative meta-framework elucidating how different motivational and volitional processes work in concert under varying contextual conditions. PSI theory explains experience and behavior by the relative activation of four cognitive systems that take over different psychological functions during goal pursuit. In this way, it may complement existing content-related explanations of clinical phenomena by introducing a functional, third-person perspective on flexible goal management, pain acceptance and goal maintenance despite pain. In line with emerging evidence on the central role of emotion regulation in chronic pain, PSI theory delineates how the self-regulation of positive and negative affect impacts whether behavior is determined by rigid stimulus-response associations (i.e., habits) or by more abstract motives and values which afford more behavioral flexibility. Along with testable hypotheses, multimodal interventions expected to address intuitive emotion regulation as a central process mediating successful adaptation to chronic pain are discussed.

Cognitive Behavioral Therapy for Chronic Pelvic Pain: What Is It and Does It Work?

PURPOSE

Urologic chronic pelvic pain syndrome (UCPPS), which encompasses interstitial cystitis/bladder pain syndrome in women and men and chronic prostatitis/chronic pelvic pain syndrome in men, is a common, often disabling urological disorder that is neither well understood nor satisfactorily treated with medical treatments. The past 25 years have seen the development and validation of a number of behavioral pain treatments, of which cognitive behavioral therapy (CBT) is arguably the most effective. CBT combines strategies of behavior therapy, which teaches patients more effective ways of behaving, and cognitive therapy, which focuses on correcting faulty thinking patterns. As a skills-based treatment, CBT emphasizes "unlearning" maladaptive behaviors and thoughts, and replacing them with more adaptive ones that support symptom self-management.

MATERIALS AND METHODS

This review describes the rationale, technical procedures, and empirical basis of CBT.

RESULTS

While evidence supports CBT for treatment-refractory chronic pain disorders, there is limited understanding of why or how CBT might work, for whom it is most beneficial, or the specific UCPPS symptoms (eg, pain, urinary symptoms) it effectively targets. This is the focus of EPPIC (Easing Pelvic Pain Interventions Clinical Research Program), a landmark NIH trial examining the efficacy of low-intensity, home-based CBT for UCPPS relative to a nonspecific comparator featuring self-care recommendations of AUA guidelines.

CONCLUSIONS

Systematic efforts to increase both the efficiency of CBT and the way it is delivered (eg, home-based treatments) are critical to scaling up CBT, optimizing its therapeutic potential, and reducing the public health burden of UCPPS.

Does subjective social status affect pain thresholds? - an experimental examination

Past research regarding the relationship between different constructs of social status and different aspects of pain has yielded divergent results. So far, there are few experimental studies to investigate the causal relationship between social status and pain. Therefore, the present study aimed to examine the effect of perceived social status on pain thresholds by experimentally manipulating participants' subjective social status (SSS). 51 female undergraduates were randomly assigned to a low- or high-status condition. Participants' perceived social standing was temporarily elevated (high SSS condition) or reduced (low SSS condition). Before and after experimental manipulation participants' pressure pain thresholds were assessed. The manipulation check confirmed that participants in the low-status condition reported significantly lower SSS than participants in the high-status condition. A linear mixed model revealed a significant group x time interaction for pain thresholds: Whereas participants' pain thresholds in the low SSS condition increased post manipulation, pain thresholds of participants in the high SSS condition decreased post manipulation (β = 0.22; 95% CI, 0.002 to 0.432; p < .05). Findings suggest that SSS may have a causal effect on pain thresholds. This effect could either be due to a change in pain perception or a change in pain expression. Future research is needed to determine the mediating factors.

Exploring HD-tDCS Effect on μ-opioid Receptor and Pain Sensitivity in Temporomandibular Disorder: A Pilot Randomized Clinical Trial Study

This study explored the association between experimentally-induced pain sensitivity and µ-opioid receptor (μOR) availability in patients with temporomandibular disorder (TMD) and further investigated any changes in the pain and μOR availability following high-definition transcranial direct current stimulation (HD-tDCS) over the primary motor cortex (M1) with pilot randomized clinical trials. Seven patients with TMD completed either active (n = 3) or sham treatment (n = 4) for 10 daily sessions and underwent positron emission tomography (PET) scans with [11C]carfentanil, a selective μOR agonist, a week before and after treatment. PET imaging consisted of an early resting and late phase with the sustained masseteric pain challenge by computer-controlled injection of 5% hypertonic saline. We also included 12 patients with TMD, obtained from our previous study, for baseline PET analysis. We observed that patients with more sensitivity to pain, indicated by lower infusion rate, had less μOR availability in the right amygdala during the late phase. Moreover, active M1 HD-tDCS, compared to sham, increased μOR availability post-treatment in the thalamus during the early resting phase and the amygdala, hippocampus, and parahippocampal gyrus during the late pain challenge phase. Importantly, increased μOR availability post-treatment in limbic structures including the amygdala and hippocampus was associated with decreased pain sensitivity. The findings underscore the role of the μOR system in pain regulation and the therapeutic potential of HD-tDCS for TMD. Nonetheless, large-scale studies are necessary to establish the clinical significance of these results. TRIAL REGISTRATION: ClinicalTrial.gov (NCT03724032) PERSPECTIVE: This study links pain sensitivity and µ-opioid receptors in patients with TMD. HD-tDCS over M1 improved µOR availability, which was associated with reduced pain sensitivity. Implications for TMD pain management are promising, but larger clinical trials are essential for validation.

Pain relief and associated factors: a cross-sectional observational web-based study in a Quebec cohort of persons living with chronic pain

Objectives

Randomized clinical trials are used to evaluate the efficacy of various pain treatments individually, while a limited number of observational studies have portrayed the overall relief experienced by persons living with chronic pain. This study aimed to describe pain relief in real-world clinical settings and to identify associated factors.

Methods

This exploratory web-based cross-sectional study used data from 1,419 persons recruited in the community. Overall pain relief brought by treatments used by participants was assessed using a 0%-100% scale (10-unit increments).

Results

A total of 18.2% of participants reported minimal pain relief (0%-20%), 60.0% moderate to substantial pain relief (30%-60%), and 21.8% extensive pain relief (70%-100%). Multivariable multinomial regression analysis revealed factors significantly associated with greater pain relief, including reporting a stressful event as circumstances surrounding the onset of pain, living with pain for ≥10 years, milder pain intensity, less catastrophic thinking, use of prescribed pain medications, use of nonpharmacological pain treatments, access to a trusted healthcare professional, higher general health scores, and polypharmacy. Factors associated with lower pain relief included surgery as circumstances surrounding pain onset, use of over-the-counter pain medications, and severe psychological distress.

Discussion

In this community sample of persons living with chronic pain, 8 out of 10 persons reported experiencing at least moderate relief with their treatment. The analysis has enabled us to explore potential modifiable factors as opportunities for improving the well-being of persons living with chronic pain.

Rasch analysis of the Depression, Anxiety, and Stress Scale in patients with chronic pain

OBJECTIVE

Questionnaires are commonly used to assess and screen pain-related, psychological symptoms in patients with chronic pain. In Germany, the "German pain questionnaire" provided by the German Pain Society used for this purpose includes the Depression, Anxiety, and Stress Scale (DASS). This study aims to analyze the DASS by fitting its data to the Rasch model to test the psychometric quality.

STUDY DESIGN AND SETTING

In this cross-sectional study, 932 patients with chronic pain answered the DASS. The 21-item short version was tested via Rasch analysis using the parameters threshold order, fit to the model, Differential Item Functioning, unidimensionality and reliability.

RESULTS

The Rasch analysis results showed a low reliability, misfitting items, Differential Item Functioning or multidimensionality. It was necessary to remove items from the subscales to improve fit to the Rasch model. A revised depression subscale of the DASS-21 was the only scale that achieved all the required psychometric parameters. The summation of all items to a total scale was not supported.

CONCLUSION

More research is required on somatic free measurement of psychological symptoms in patients with chronic pain. The results demonstrate that the development of a new instrument or a revision of existing instruments for screening of psychological symptoms in chronic pain are needed.

Virtual reality is effective in the management of chronic low back ache in adults: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Chronic low back ache (CLBA) is a common condition that is conventionally managed with physical therapy and analgesics. Recently, virtual reality-based interventions have been tried out in the management of CLBA. Their effectiveness, however has not been established. This meta-analysis aims to find out if the application of VR will lead to better pain relief, as compared to conventional techniques in adults with CLBA.

METHODS

The literature search was carried out in three online databases for potential randomized controlled trials that compared VR-based interventions with conventional treatment in CLBA. Data on outcome parameters were recorded. Meta-analysis was carried out with the help of appropriate software.

RESULTS

Seven studies having data on 507 subjects were included in the meta-analysis. Their mean ages were 48.4 years. There were 252 subjects in the VR group and 255 in the control group. VR-based interventions were found to have a statistically significant improvement in the pain intensity compared with conventional techniques (p - 0.005).

CONCLUSION

VR-based interventions are effective in the management of CLBA in the short term. Further research with longer follow-up is required to evaluate if these improvements are persistent in the long term.

Pain-sensorimotor interactions: New perspectives and a new model

How pain and sensorimotor behavior interact has been the subject of research and debate for many decades. This article reviews theories bearing on pain-sensorimotor interactions and considers their strengths and limitations in the light of findings from experimental and clinical studies of pain-sensorimotor interactions in the spinal and craniofacial sensorimotor systems. A strength of recent theories is that they have incorporated concepts and features missing from earlier theories to account for the role of the sensory-discriminative, motivational-affective, and cognitive-evaluative dimensions of pain in pain-sensorimotor interactions. Findings acquired since the formulation of these recent theories indicate that additional features need to be considered to provide a more comprehensive conceptualization of pain-sensorimotor interactions. These features include biopsychosocial influences that range from biological factors such as genetics and epigenetics to psychological factors and social factors encompassing environmental and cultural influences. Also needing consideration is a mechanistic framework that includes other biological factors reflecting nociceptive processes and glioplastic and neuroplastic changes in sensorimotor and related brain and spinal cord circuits in acute or chronic pain conditions. The literature reviewed and the limitations of previous theories bearing on pain-sensorimotor interactions have led us to provide new perspectives on these interactions, and this has prompted our development of a new concept, the Theory of Pain-Sensorimotor Interactions (TOPSMI) that we suggest gives a more comprehensive framework to consider the interactions and their complexity. This theory states that pain is associated with plastic changes in the central nervous system (CNS) that lead to an activation pattern of motor units that contributes to the individual's adaptive sensorimotor behavior. This activation pattern takes account of the biological, psychological, and social influences on the musculoskeletal tissues involved in sensorimotor behavior and on the plastic changes and the experience of pain in that individual. The pattern is normally optimized in terms of biomechanical advantage and metabolic cost related to the features of the individual's musculoskeletal tissues and aims to minimize pain and any associated sensorimotor changes, and thereby maintain homeostasis. However, adverse biopsychosocial factors and their interactions may result in plastic CNS changes leading to less optimal, even maladaptive, sensorimotor changes producing motor unit activation patterns associated with the development of further pain. This more comprehensive theory points towards customized treatment strategies, in line with the management approaches to pain proposed in the biopsychosocial model of pain.

Patient Motivation to Reduce or Discontinue Opioids for Chronic Pain: Self-efficacy, Barriers, and Readiness to Change

OBJECTIVES

This study aimed to assess levels and predictors of self-efficacy and motivation to change opioid use among a community sample of patients using opioids for chronic pain, as well as patient-reported barriers to pursuing opioid discontinuation.

METHODS

Participants with a variety of chronic pain conditions, recruited from ResearchMatch.org , completed a battery of electronic, self-report questionnaires assessing demographic and medical characteristics, pain treatment history, and levels of readiness, self-efficacy, and other attitudes toward reducing or discontinuing opioid use. Multiple regression analyses and analyses of variance were conducted to examine predictors of readiness and self-efficacy to change opioid use. A modified version of rapid qualitative analysis was utilized to analyze themes in participant responses to an open-ended item about "what it would take" to consider opioid discontinuation.

RESULTS

The final sample included N=119 participants, the majority of whom were female (78.2%), Caucasian (77.3%), and well-educated. Readiness and self-efficacy to decrease or stop opioid use were fairly low on a 0 to 10 Visual Analog Scale (2.6 to 3.8) and significantly higher to decrease than stop ( P <0.01). Higher readiness to change was predicted by lower pain severity and higher concern about opioids, whereas higher self-efficacy was predicted by shorter pain duration. Results from the qualitative analyses revealed that the availability of an alternative treatment option was the most commonly cited requirement to consider opioid discontinuation.

DISCUSSION

Patients with lower pain severity, shorter duration of pain, and higher concerns about opioids may be a prime target from a motivation standpoint for interventions addressing opioid tapering and discontinuation.

Race-Based Differences in the Response to a Mindfulness Based Integrative Medical Group Visit Intervention for Chronic Pain

Background

Chronic pain is one of the most common drivers of healthcare utilization and a marked domain for health disparities, as African American/Black populations experience high rates of chronic pain. Integrative Medical Group Visits (IMGV) combine mindfulness techniques, evidence-based integrative medicine, and medical group visits. In a parent randomized controlled trial, this approach was tested as an adjunct treatment in a diverse, medically underserved population with chronic pain and depression.

Objective

To determine race-based heterogeneity in the effects of a mindfulness based treatment for chronic pain.

Methods

This secondary analysis of the parent trial assessed heterogeneity of treatment effects along racialized identity in terms of primary patient-reported pain outcomes in a racially diverse sample suffering from chronic pain and depression. The analytic approach examined comorbidities and sociodemographics between racialized groups. RMANOVAs examined trajectories in pain outcomes (average pain, pain severity, and pain interference) over three timepoints (baseline, 9, and 21 weeks) between participants identifying as African American/Black (n = 90) vs White (n = 29) across both intervention and control conditions.

Results

At baseline, African American/Black participants had higher pain severity and had significantly different age, work status, and comorbidity profiles. RMANOVA models also identified significant race-based differences in the response to the parent IMGV intervention. There was reduced pain severity in African American/Black subjects in the IMGV condition from baseline to 9 weeks. This change was not observed in White participants over this time period. However, there was a reduction in pain severity in White participants over the subsequent interval from 9 to 21 week where IMGV had no significant effect in African American/Black subjects during this latter time period.

Conclusion

Interactions between pain and racialization require further investigation to understand how race-based heterogeneity in the response to integrative medicine treatments for chronic pain contribute to the broader landscape of health inequity.

Sustainability of cognitive behavioural interventions for chronic back pain: A long-term follow-up

BACKGROUND

There is a significant research gap with respect to the long-term sustainability of psychological treatment effects in chronic pain patients. This study aimed to investigate long-term treatment effects of two psychological treatments: cognitive behavioural therapy (CBT) as a broad-spectrum approach and exposure as a specific intervention for fear-avoidant pain patients.

METHODS

Patients with chronic low back pain were randomized to CBT or exposure in vivo. Long-term follow-up (LTFU) data were available for 64 patients up to 8 years after treatment, with a response rate of 73%. The primary outcomes were pain-related disability and pain intensity and secondary outcomes were emotional distress, psychological flexibility, catastrophizing and pain-related fear. The data analysis was performed with longitudinal multilevel modelling.

RESULTS

Multilevel analyses showed improvements in all primary outcomes as well as all secondary outcomes from pre-treatment to LTFU for both treatments. The mean proportion of cases meeting reliable and clinical improved criteria in all primary outcome was 36% (range: 22%-46%) in the exposure group and 50% (range: 33%-60%) in the CBT group. Dropout analyses revealed significantly higher deterioration rates over time. Pre-treatment to LTFU effect sizes of the primary outcomes ranged from 0.54 to 1.59.

CONCLUSIONS

Our results indicate that the effects of psychological treatments might be stable over several years. Treatment gains for exposure as a stand-alone treatment seem to be of shorter duration than a general CBT intervention. Thus, psychological treatments might offer a promising and sustainable long-term perspective for patients with chronic back pain.

SIGNIFICANCE

The long-term stability of treatment effects is a highly neglected issue despite its inherent importance in the context of chronic pain. This study is the first to investigate treatment effects of cognitive behavioural therapy and in vivo exposure in chronic back pain sufferers up to 8 years after treatment. The findings contribute to an understanding of the sustainability of psychological cognitive behavioural therapy-based intervention effects.

A Randomized Controlled Neuroimaging Trial of Cognitive Behavioral Therapy for Fibromyalgia Pain

OBJECTIVE

Fibromyalgia (FM) is characterized by pervasive pain-related symptomatology and high levels of negative affect. Mind-body treatments such as cognitive behavioral therapy (CBT) appear to foster improvement in FM via reductions in pain-related catastrophizing, a set of negative, pain-amplifying cognitive and emotional processes. However, the neural underpinnings of CBT's catastrophizing-reducing effects remain uncertain. This randomized controlled mechanistic trial was designed to assess CBT's effects on pain catastrophizing and its underlying brain circuitry.

METHODS

Of 114 enrolled participants, 98 underwent a baseline neuroimaging assessment and were randomized to 8 weeks of individual CBT or a matched FM education control (EDU) condition.

RESULTS

Compared with EDU, CBT produced larger decreases in pain catastrophizing post treatment (P < 0.05) and larger reductions in pain interference and symptom impact. Decreases in pain catastrophizing played a significant role in mediating those functional improvements in the CBT group. At baseline, brain functional connectivity between the ventral posterior cingulate cortex (vPCC), a key node of the default mode network (DMN), and somatomotor and salience network regions was increased during catastrophizing thoughts. Following CBT, vPCC connectivity to somatomotor and salience network areas was reduced.

CONCLUSION

Our results suggest clinically important and CBT-specific associations between somatosensory/motor- and salience-processing brain regions and the DMN in chronic pain. These patterns of connectivity may contribute to individual differences (and treatment-related changes) in somatic self-awareness. CBT appears to provide clinical benefits at least partially by reducing pain-related catastrophizing and producing adaptive alterations in DMN functional connectivity.

Hidden family rules: perspective on a dysfunctional paternalistic system and the persistence of pain

This article explores how paternalistic control and power reside within the family system and how this may influence pain and its persistence. Drawing upon clinical case studies and existing literature, this exploration emphasises the role of paternal dysfunction in creating emotional memory images and delves into how this may influence the chronification and treatment resistance of pain (i.e., making pain "sticky"). We argue that a dysfunctional paternalistic family system, often characterised by authoritarian dynamics, emotional neglect, and abuse, results in adverse experiences and emotional memory images that create a fertile ground for the entrenchment and propagation of psychosomatic symptoms, including pain. Further, the paper emphasizes the potential intergenerational effects of such a scenario, where inherited "Family Rules" drive maladaptive coping mechanisms, which contribute to the persistence of psychological and physiological distress across generations. Understanding these complexities offers new perspectives on treating psychological disorders and their physiological ramifications. It also highlights the urgency of addressing dysfunctional familial dynamics in psychotherapeutic interventions for both immediate and long-term psychophysiological health outcomes.

Graph theory analysis reveals an assortative pain network vulnerable to attacks

The neural substrate of pain experience has been described as a dense network of connected brain regions. However, the connectivity pattern of these brain regions remains elusive, precluding a deeper understanding of how pain emerges from the structural connectivity. Here, we employ graph theory to systematically characterize the architecture of a comprehensive pain network, including both cortical and subcortical brain areas. This structural brain network consists of 49 nodes denoting pain-related brain areas, linked by edges representing their relative incoming and outgoing axonal projection strengths. Within this network, 63% of brain areas share reciprocal connections, reflecting a dense network. The clustering coefficient, a measurement of the probability that adjacent nodes are connected, indicates that brain areas in the pain network tend to cluster together. Community detection, the process of discovering cohesive groups in complex networks, successfully reveals two known subnetworks that specifically mediate the sensory and affective components of pain, respectively. Assortativity analysis, which evaluates the tendency of nodes to connect with other nodes that have similar features, indicates that the pain network is assortative. Finally, robustness, the resistance of a complex network to failures and perturbations, indicates that the pain network displays a high degree of error tolerance (local failure rarely affects the global information carried by the network) but is vulnerable to attacks (selective removal of hub nodes critically changes network connectivity). Taken together, graph theory analysis unveils an assortative structural pain network in the brain that processes nociceptive information. Furthermore, the vulnerability of this network to attack presents the possibility of alleviating pain by targeting the most connected brain areas in the network.

Impact of socioeconomic status on new chronic opioid use after gastric bypass surgery

BACKGROUND

Socioeconomic status may influence weight loss, postoperative complications, and health-related quality of life after bariatric surgery. Chronic use of opioid analgesics is a known risk after bariatric surgery, but whether socioeconomic factors are associated with new chronic use of opioid analgesics has not been investigated in depth.

OBJECTIVES

The aim of this study was to identify socioeconomic factors associated with the development of new chronic use of opioid analgesics after gastric bypass surgery.

SETTING

All hospitals performing bariatric surgery in Sweden.

METHODS

This was a retrospective cohort study with prospectively collected data including all primary gastric bypass procedures in Sweden between 2007 and 2015. Data were collected from the Scandinavian Obesity Surgery Registry, the Swedish Prescribed Drug Register, and Statistics Sweden. The primary outcome was new chronic opioid use.

RESULTS

Of the 44,671 participants, 1438 patients became new chronic opioid users. Longer education (secondary education; odds ratio [OR] = .71; 95% CI, .62-.81) or higher education (OR = .45; 95% CI, .38-.53), higher disposable income (20th-50th percentile: OR = .75; 95% CI, .66-.85; 50th-80th percentile: OR = .50; 95% CI, .43-.58; and the highest 80th percentile: OR = .40; 95% CI, .32-.51) were significantly associated with lower risk for new chronic opioid use. Being a second-generation immigrant (OR = 1.54; 95% CI, 1.24-1.90), being on a disability pension or early retirement (OR = 3.04; 95% CI, 2.67-3.45), receiving social benefits (OR = 1.88; 95% CI, 1.59-2.22), being unemployed for <100 days (OR = 1.25; 95% CI, 1.08-1.45), being unemployed for >100 days (OR = 1.41; 95% CI, 1.16-1.71), and being divorced or a widow or widower (OR = 1.35; 95% CI, 1.17-1.55) were significantly associated with a higher risk for chronic opioid use.

CONCLUSION

Given that long-term opioid use has detrimental effects after bariatric surgery, it is important that information and follow-up are optimized for patients with shorter education, lower income, and disability pension or early retirement because they are at an increased risk of new chronic opioid analgesics use.

The impact of the social context on the development of secondary hyperalgesia: an experimental study

ABSTRACT

Social support has been shown to reduce pain ratings and physiological responses to acute pain stimuli. Furthermore, this relationship is moderated by adult attachment styles. However, these effects have not been characterized in experimentally induced symptoms of chronic pain, such as secondary hyperalgesia (SH) which is characterized by an increased sensitivity of the skin surrounding an injury. We aimed to examine whether social support by handholding from a romantic partner can attenuate the development of experimentally induced SH. Thirty-seven women, along with their partners, participated in 2 experimental sessions 1 week apart. In both sessions, SH was induced using an electrical stimulation protocol. In the support condition, the partner was seated across from the participant holding the participant's hand during the electrical stimulation, whereas in the alone condition, the participant went through the stimulation alone. Heart rate variability was measured for both the participant as well as the partner before, during, and after the stimulation. We found that the width of the area of hyperalgesia was significantly smaller in the support condition. Attachment styles did not moderate this effect of social support on the area width. Increasing attachment avoidance was associated with both a smaller width of hyperalgesia and a smaller increase in the sensitivity on the stimulated arm. For the first time, we show that social support can attenuate the development of secondary hyperalgesia and that attachment avoidance may be associated with an attenuated development of secondary hyperalgesia.

Real-world outcomes in spinal cord stimulation: predictors of reported effect and explantation using a comprehensive registry-based approach

Introduction

Despite advancements in implanted hardware and development of novel stimulation paradigms in Spinal Cord Stimulation (SCS), real world evidence suggests a large variation in patient reported outcomes and a proportion of patients are later explanted due to loss of analgesia. Possible predictors for outcome have been explored in smaller short-term evaluations, but few clinically applicable robust measures for long term outcome have emerged.

Methods

We performed a comprehensive retrospective study based on an assembled patient-level aggregated database from multiple local and national registries in Sweden. Variables associated with risk of explantation (due to insufficient analgesia) and analgesic effect was analyzed using a Cox regression analysis and an ordered logit regression model, respectively.

Results

We found the accumulated risk of explantation due to loss of analgesia to be 10% and 21% at two and ten years follow up, respectively. The use of 10 kHz spinal cord stimulation (compared with Tonic waveform; p = 0.003), and being 60 years or older (reference 18-40 years; p = 0.003) were associated with an increased risk of explantation.At a mean follow up at 1 year, 48% of patients reported a pain intensity reduction from baseline of at least 30%. Secondary (p = 0.030) and post-secondary (p = 0.001) education (compared with primary education) was associated with an increased probability of successful patient reported outcomes.

Conclusion

This study suggests that a higher educational level and being employed are associated with successful treatment outcome in patients with chronic pain treated with SCS in Sweden.

Beyond biopsychosocial: The keystone mechanism theory of pain

Pain is a deeply personal experience, with interindividual differences in its chronification and treatment presenting a formidable healthcare challenge. The biopsychosocial model (BPSm) has been hugely influential within nascent attempts at precision pain medicine, steering the field away from a reductionist biomechanical viewpoint and emphasising complex interactions of biological, psychological, and social factors which shape the individuality of pain. However, despite offering a strong theoretical foundation and holistic perspective, we contend that the BPSm remains limited in its capacity to deliver truly mechanistically informed treatment of pain. We therefore propose the keystone model of pain which offers a pragmatic balance between the dimensionality expansive BPSm and overly reductive approaches, providing both theoretical and practical advantages for the transition from treating populations to individual people.

Stressors and Pain across the Late-Life Span: Findings from Two Parent Longitudinal Studies of Aging and Health

OBJECTIVE

The objective is to determine associations between stressors and pain across the late-life span.

METHOD

Multilevel linear modeling was applied separately to harmonized repeated measures data from the Longitudinal Late-Life Health study (LLLH; n = 342; 13-year interval) and the Health and Retirement Study (HRS; n = 2959; 8-year interval).

RESULTS

In both the LLLH and HRS samples, independent of age, gender, and race, participants with higher average stressor levels experienced more numerous painful conditions and higher pain severity over the study intervals. In the HRS sample, they also experienced higher levels of pain interference. In general, participants' stressor levels did not influence rates of increase in their pain. Gender and race had few moderating effects on associations between stressors and pain.

DISCUSSION

Stressors and pain are associated across the late-life span. Future research should focus on the mediating mechanisms that account for this association and the moderating factors that affect its strength.

Use of Psychedelics for Pain: A Scoping Review

Chronic pain is a public health concern that affects approximately 1.5 billion people globally. Conventional therapeutic agents including opioid and non-opioid analgesics have been associated with adverse side effects, issues with addiction, and ineffective analgesia. Novel agents repurposed to treat pain via different mechanisms are needed to fill the therapeutic gap in chronic pain management. Psychedelics such as lysergic acid diethylamide and psilocybin (the active ingredient in psychedelic mushrooms) are thought to alter pain perception through direct serotonin receptor agonism, anti-inflammatory effects, and synaptic remodeling. This scoping review was conducted to identify human studies in which psychedelic agents were used for the treatment of pain. Twenty-one articles that assessed the effects of psychedelics in treating various pain states were included. The present scarcity of clinical trials and small sample sizes limit their application for clinical use. Overall, psychedelics appear to show promise for analgesia in patients with certain headache disorders and cancer pain diagnoses. Future studies must aim to examine the combined effects of psychotherapy and psychedelics on chronic pain.

Past Adversity Influencing Now (PAIN): perspectives on the impact of temporal language on the persistence of pain

Persistent pain is a significant healthcare issue, often unresponsive to traditional treatments. We argue for incorporating non-biomedical perspectives in understanding pain, promoting more comprehensive solutions. This article explores how language, specifically time-related terms, may affect the persistence (stickiness) of pain. We delve into how language influences one's experience of the world, especially in understanding pain through spatial metaphors. Notably, time perceptions differ across languages and cultures and there is no absolute construct of temporal pain experience. In English, time is viewed linearly as past, present, and future. We introduce a framework called Past Adversity Influencing Now (PAIN) which includes various temporal phases of pain; Past Perfect, Past Imperfect, Present, Future Imperfect, and Future Perfect. We suggest that past negative memories (emotional memory images) can "trap" individuals in a "sticky" pain state. We speculate that the process of diagnosing pain as "chronic" may solidify this "stickiness", drawing from the ancient Greek idea of "logos", where pain communicates a message across time and space needing recognition. Our PAIN framework encourages examining pain through a temporal lens, guiding individuals towards a more positive future.

Predictors of persisting pain in children with Juvenile Idiopathic Arthritis: a case control study nested in the ReACCh-Out cohort

BACKGROUND

To identify baseline predictors of persisting pain in children with Juvenile Idiopathic Arthritis (JIA), relative to patients with JIA who had similar baseline levels of pain but in whom the pain did not persist.

METHODS

We used data from the Research in Arthritis in Canadian Children emphasizing Outcomes (ReACCh-Out) inception cohort to compare cases of 'moderate persisting pain' with controls of 'moderate decreasing pain'. Moderate pain was defined as a Visual Analogue Scale (VAS) for pain measurement score of > 3.5 cm. Follow-up was minimum 3 years. Univariate and Multivariate logistic regression models ascertained baseline predictors of persisting pain.

RESULTS

A total of 31 cases and 118 controls were included. Mean pain scores at baseline were 6.4 (SD 1.6) for cases and 5.9 (1.5) for controls. A greater proportion of cases than controls were females (77.4% vs 65.0%) with rheumatoid factor positive polyarthritis (12.9% vs 4.2%) or undifferentiated JIA (22.6% vs 8.5%). Oligoarthritis was less frequent in cases than controls (9.7% vs 33%). At baseline, cases had more active joints (mean of 11.4 vs 7.7) and more sites of enthesitis (4.6 vs 0.7) than controls. In the final multivariate regression model, enthesitis count at baseline (OR 1.40, CI 95% 1.19-1.76), female sex (4.14, 1.33-16.83), and the overall Quality of My Life (QoML) baseline score (0.82, 0.69-0.98) predicted development of persisting pain.

CONCLUSIONS

Among newly diagnosed children with JIA with moderate pain, female sex, lower overall quality of life, and higher enthesitis counts at baseline predicted development of persisting pain. If our findings are confirmed, patients with these characteristics may be candidates for interventions to prevent development of chronic pain.

Perspectives on the insidious nature of pain metaphor: we literally need to change our metaphors

Metaphorical language is used to convey one thing as representative or symbolic of something else. Metaphor is used in figurative language but is much more than a means of delivering "poetic imagination". A metaphor is a conceptual tool for categorising, organizing, thinking about, and ultimately shaping reality. Thus, metaphor underpins the way humans think. Our viewpoint is that metaphorical thought and communication contribute to "painogenicity", the tendency of socio-ecological environments (settings) to promote the persistence of pain. In this perspectives article, we explore the insidious nature of metaphor used in pain language and conceptual models of pain. We explain how metaphor shapes mental organisation to govern the way humans perceive, navigate and gain insight into the nature of the world, i.e., creating experience. We explain how people use metaphors to "project" their private sensations, feelings, and thoughts onto objects and events in the external world. This helps people to understand their pain and promotes sharing of pain experience with others, including health care professionals. We explore the insidious nature of "warmongering" and damage-based metaphors in daily parlance and demonstrate how this is detrimental to health and wellbeing. We explore how metaphors shape the development and communication of complex, abstract ideas, theories, and models and how scientific understanding of pain is metaphorical in nature. We argue that overly simplistic neuro-mechanistic metaphors of pain contribute to fallacies and misnomers and an unhealthy focus on biomedical research, in the hope of developing medical interventions that "prevent pain transmission [sic]". We advocate reconfiguring pain language towards constructive metaphors that foster a salutogenic view of pain, focusing on health and well-being. We advocate reconfiguring metaphors to align with contemporary pain science, to encourage acceptance of non-medicalised strategies to aid health and well-being. We explore the role of enactive metaphors to facilitate reconfiguration. We conclude that being cognisant of the pervasive nature of metaphors will assist progress toward a more coherent conceptual understanding of pain and the use of healthier pain language. We hope our article catalyses debate and reflection.

Sex-related correspondence between mechanical hypersensitivity and the discharge of medullary pain control neurons in neuropathic rats

Here we studied whether the sex-related difference in mechanical hypersensitivity induced by neuropathy is associated with the discharge rate of medullary pain control neurons. We performed experiments in male and female rats with spared nerve injury (SNI) model of peripheral neuropathy. Mechanical hypersensitivity was assessed behaviorally by monofilaments. Discharge rates of pain-control neurons were determined using in vivo single unit recordings under light anesthesia. Recording targets were two medullary nuclei involved in descending pain control: the rostral ventromedial medulla (RVM) and the medullary dorsal reticular nucleus (DRt). Based on the response to peripheral noxious stimulus, neurons were classified as pronociceptive RVM ON-like or DRt neurons, or antinociceptive RVM OFF-like neurons. Behavioral results indicated that the mechanical hypersensitivity induced by SNI was significantly stronger in females than males. The ongoing discharge rates of pronociceptive RVM ON-like neurons were higher and those of antinociceptive RVM OFF-like neurons lower in SNI females than SNI males. Ongoing discharge rates of pronociceptive DRt neurons were not significantly different between SNI females and males. The results suggest that a sex difference in the discharge rate of pain control neurons in the RVM but not DRt may contribute to the maintenance of stronger neuropathic hypersensitivity in females.