Chronic pain as a symptom or a disease: the IASP Classification of Chronic Pain for the International Classification of Diseases (ICD-11)

The inflammatory and genetic mechanisms underlying the cumulative effect of co-occurring pain conditions on depression

Chronic pain conditions frequently coexist and share common genetic vulnerabilities. Despite evidence showing associations between pain and depression, the additive effect of co-occurring pain conditions on depression risk and the underlying mechanisms remain unclear. Leveraging data from 431,038 UK Biobank participants with 14-year follow-up, we found a significantly increased risk of depression incidence in individuals reporting pain, irrespective of body site or duration (acute or chronic), compared with pain-free individuals. The depression risk increased with the number of co-occurring pain sites. Mendelian randomization supported potential causal inference. We constructed a composite pain score by combining individual effects of acute or chronic pain conditions across eight body sites in a weighted manner. We found that depression risks increased monotonically in parallel with composite pain scores. Moreover, some inflammatory markers, including C-reactive protein, partially mediated the association between composite pain scores and depression risk. Considering the high prevalence of comorbid depression and pain, pain screening may help identify high-risk individuals for depression.

Exploring the Role of RhoA/ROCK Signaling in Pain: A Narrative Review

Despite significant progress in understanding the mechanisms of pain and developing therapeutic agents, pain remains a challenging and unresolved clinical issue. The Ras homolog gene family member A (RhoA), a member of the small guanosine triphosphate hydrolases (GTPases) of the Ras homolog family, is involved in transmitting signals that regulate various cellular processes. RhoA exerts its effects through a range of downstream effectors, with Rho-associated kinase (ROCK) being the most extensively studied. Emerging evidence suggests that the RhoA/ROCK signaling pathway plays a crucial role in pain transmission and sensitization. Our work indicates that targeting the RhoA/ROCK signaling pathway may offer a promising therapeutic avenue for alleviating pain.

The Intersection of Sarcopenia and Musculoskeletal Pain: Addressing Interconnected Challenges in Aging Care

The global aging population faces a growing prevalence of sarcopenia and musculoskeletal (MSK) pain, two interrelated conditions that diminish physical function, quality of life, and independence in older adults. Sarcopenia, characterized by the loss of muscle strength, mass, and function, often coexists with MSK pain, with emerging evidence suggesting that each condition may contribute to the progression of the other. This perspective explores the bidirectional relationship between sarcopenia and MSK pain, highlighting shared mechanisms, including inactivity, cellular aging, chronic inflammation, gender-related hormonal changes, and psychosocial factors such as depression and social isolation, which underlie the mutual exacerbation between conditions. Through a multidisciplinary framework, the article emphasizes integrating care across specialties to address these interconnected conditions. Practical approaches, including comprehensive screening protocols, tailored resistance exercise, and nutritional support, are discussed alongside innovative hybrid care models combining in-person and telemedicine systems to enhance accessibility and continuity of care. A call to action is presented for clinicians, policymakers, and researchers to adopt collaborative strategies, prioritize investment in integrated healthcare, and bridge critical knowledge gaps. By reframing care delivery and advancing multidisciplinary efforts, this perspective aims to effectively address the complex challenges posed by the intersection of sarcopenia and MSK pain in older adults.

Common neural correlates of chronic pain - A systematic review and meta-analysis of resting-state fMRI studies

Maladaptive brain plasticity has been reported in chronic pain (CP) conditions, though it remains unclear if there are common alterations across pathologies. Therefore, we systematically synthesized literature comparing resting-state functional magnetic resonance imaging (rs-fMRI) in CP patients and healthy controls (HC), and meta-analyzed data whenever applicable. Separate meta-analyses were performed for each method - (fractional) amplitude of low-frequency fluctuations (fALFF, ALFF), regional homogeneity (ReHo), seed-based connectivity (according to the seed) and independent component analysis (according to the network). In qualitative synthesis, sensory-discriminative pain processing - thalamus, insula, temporal and sensory cortices - and cognitive and emotional processing - cingulate, prefrontal and parietal cortices and precuneus - regions concentrated CP/HC differences. Meta-analyses revealed decreased ALFF and increased ReHo in the precuneus, increased fALFF in the left posterior insula and disrupted within- and cross-network connectivity of default mode network (DMN) nodes, as well as altered connectivity in top-down pain modulation pathways. Specifically, it showed decreased anterior and increased posterior components' representation within DMN, enhanced connectivity between the medial prefrontal cortex (mPFC, part of the DMN) and anterior insula (part of the salience network), and decreased mPFC connectivity with the periaqueductal gray matter (PAG). Collectively, results suggest that CP disrupts the natural functional organization of the brain, particularly impacting DMN nodes (mPFC and precuneus), insula and top-town pain modulation circuits.

Investigating the Prevalence and Level of Pain Experienced by Australian Farmers

OBJECTIVES

This study evaluated the prevalence and level of pain in Australian farmers and how these compare to the general working population. We also explored factors related to the interference of pain on farmers' work.

DESIGN

Logistic regressions were used to examine the prevalence of chronic pain and pain interference with normal work among farmers compared to the general working population, and also to examine the factors associated with pain interference in farmers. A multinomial logistic regression model was used to examine the level of bodily pain among farmers compared to the general working population.

SETTING

The nationally representative HILDA (Household, Income, and Labour Dynamics Australia) survey data (wave 21) was used.

PARTICIPANTS

The final sample included 168 (1.6%) farmers and 10 318 (98.4%) people in the general working population.

RESULTS

There was a higher prevalence of chronic pain (p < 0.001), higher levels of bodily pain (p < 0.001), and pain interference with normal work (p < 0.001) in farmers than in the general working population. Age, gender, Body Mass Index (BMI), education level, remoteness, and personal social cohesion were not associated with pain interference with normal work in farmers.

CONCLUSION

The prevalence of chronic pain, level of bodily pain, and pain interference with normal work in Australian farmers is higher than the general working population. However, information is lacking on the factors that influence pain for this unique group. Further exploration is needed into why factors that are commonly associated with pain are not associated with pain in the farming population.

Which type and dosage of mindfulness-based interventions are most effective for chronic pain? A systematic review and network meta-analysis

Chronic pain exerts an enormous personal and economic burden worldwide. While clinical trials have confirmed the benefits of mindfulness-based interventions (MBIs) in chronic pain management, knowledge on the best type and dosage remains unknown. This study aims to compare the clinical effectiveness of different MBIs on chronic pain and to identify the optimal dosage of MBIs. The primary outcome was pain intensity and secondary outcomes were physical function and depression. We applied a random-effect pairwise meta-analysis to synthesize data, and network meta-analysis to compare effectiveness among different types and dosages of MBIs. The findings were further categorized according to the partially contextualized framework. A total of 68 studies with 5,339 participants were included. Mindfulness-based stress reduction demonstrated the most promising results for improving pain intensity (SMD -0.76, 95 % CI -1.06 to -0.46, Surface Under the Cumulative Ranking Area (SUCRA) 0.75) and depression (SMD -0.77, 95 % CI -0.98 to -0.56, SUCRA 0.86), supported by moderate and high certainty of evidence, respectively. On the other hand, mindfulness-oriented recovery enhancement emerged as the most effective for enhancing physical function (SMD -1.42, 95 % CI -2.28 to -0.57, SUCRA 0.96), albeit with low certainty of evidence. An 8-week course, conducted once per week, with sessions lasting between 90 and 120 min, appeared to be the optimal dosage for addressing pain intensity, physical function, and depression. Our findings contribute to the evidence supporting the use of MBIs in chronic pain management and informing the development of evidence-based guidelines and standardizing the course structures of MBIs. Systematic review registration: PROSPERO CRD42021293938.

Evaluating the efficacy of transcranial direct current stimulation (tDCS) in managing neuropathic pain-induced emotional consequences: Insights from animal models

Neuropathic pain is a global health concern due to its severity and its detrimental impact on patients' quality of life. It is primarily characterized by sensory alterations, most commonly hyperalgesia and allodynia. As the disease progresses, patients with neuropathic pain develop co-occurring emotional disorders, such as anxiety and depression, which further complicate therapeutic management. While pharmacotherapy remains the first-line treatment, limitations in its efficacy and the prevalence of side effects often leave patients with insufficient pain relief. Transcranial direct current stimulation (tDCS), a non-invasive brain stimulation technique, has recently emerged as a promising alternative for chronic pain management. This review provides an overview of preclinical studies examining the effects of tDCS in rodent models of neuropathic pain. It specifically highlights the potential of tDCS to modulate the emotional-affective component of pain, with a focus on identifying optimal cortical targets for stimulation to enhance the translational application of tDCS in managing pain-related emotional disorders.

The impact of photovoice on the report of emotions in individuals with persistent physical symptoms: Results of an experimental trial

OBJECTIVE

Identifying and reporting emotions can be challenging for individuals with persistent physical symptoms (PPS), like tinnitus or tension-type headaches. Photovoice (PV) helps people identify and report their emotions by photographing relevant objects or situations. The aim of our study was to examine whether PV facilitates the report of emotions in individuals with PPS.

METHODS

We randomly assigned 169 participants with PPS to one of three groups: a PV group, a writing group, or a passive control group. The PV group took daily photographs related to their symptoms and coping, the writing group wrote keywords, and the passive control group had no task. After a week, all participants completed an online writing task about their symptoms and coping, which was analyzed for the number of emotion words used. We also assessed self-reported affect, ability to identify and report emotions, and self-disclosure.

RESULTS

Participants in the PV group used more emotion words in the writing task than the control groups. Specifically, the PV group used significantly more positive emotion words (F(2,166) = 26.86, p < .001) and fewer negative emotion words (F(2,166) = 8.28, p < .001) compared to the writing and control groups. No significant group differences were found for self-reported affect and self-disclosure.

CONCLUSIONS

PV promises to facilitate more positive, nuanced, and detailed reporting of emotions and may be therapeutically useful in gathering richer insights from the participant's perspective. Future research should target individuals who respond best to PV and develop tailored treatment to increase treatment effects.

The prevalence of chronic pain and its impact on activities of daily living disability and depressive symptoms according to multiple definitions in a Japanese population: the Hisayama study

Objectives

This study aimed to compare the prevalence of chronic pain using various definitions from previous studies and to determine the optimal definition for detecting chronic pain associated with physical and emotional dysfunction in a general Japanese population.

Methods

A total of 2700 community-dwelling Japanese residents aged ≥40 years were assessed for chronic pain and its components of duration, frequency, and intensity. The activities of daily living (ADL) disability and depressive symptoms of participants were also evaluated using the modified Lankin Scale and Patient Health Questionnaire-9. The odds ratios and the population attributable fractions (PAFs) for ADL disability and depressive symptoms were estimated using a logistic regression model.

Results

The prevalence of chronic pain varied greatly by definition, ranging from 13% for pain defined as pain duration ≥3 months, pain frequency ≥ twice a week, and pain intensity of ≥50 mm by a visual analogue scale (VAS) to 48% for a simple definition of pain duration ≥3 months. The PAFs for ADL disability and depressive symptoms were relatively high at 33% in participants with pain duration of ≥6 months and 30% in those with pain frequency of ≥twice a week, while the VAS ≥50 mm group had a low PAF of 12%.

Conclusion

For screening people with chronic pain and ADL disability or depressive symptoms, the criteria of pain duration and pain frequency yielded essentially identical results, while the criterion of pain intensity risked overlooking individuals with chronic pain and these associated symptoms.

Structural and dynamic characteristics in sonographic evaluation of the sciatic nerve in patients with probable neuropathic pain - A cross-sectional study

INTRODUCTION

Structural and dynamic alterations of peripheral nerves are commonly observed in patients with radiculopathy. The current study aimed to compare the cross-sectional area (CSA), echogenicity index (ECHO), and skin-to-nerve distance (SKN) of the sciatic nerve between the symptomatic and asymptomatic sides of patients with probable neuropathic pain under different levels of nerve tension.

METHODS

A cross-sectional study was conducted with 31 participants classified as having probable chronic neuropathic pain. The CSA, ECHO, and SKN of the sciatic nerve of both lower limbs were measured in the following positions: A) flexed knee and neutral ankle, B) extended knee and ankle plantarflexion, and C) extended knee and ankle dorsiflexion. Sonographic measurements of both lower limbs were compared using repeated measures analysis of variance.

RESULTS

The mean age of the sample was 44 years (SD 10; 77.4% females), and the mean pain intensity was 5.3 (SD 1.9) out of 10 on the Numeric Pain Rating Scale. No significant differences were found for CSA, ECHO, or SKN measurements between the symptomatic and asymptomatic sides for the three tested positions. Position C had a smaller CSA of the sciatic nerve on both sides compared to position A. Both sides exhibited the nerve being more superficial in position C compared to the other positions.

CONCLUSION

Participants with probable chronic neuropathic pain had similar CSA, ECHO, and SKN of the sciatic nerve between the symptomatic and asymptomatic lower limbs. Increasing sciatic nerve tension (position C) reduced CSA and caused superficial nerve displacement on both sides.

Factors associated with impaired physical functionality in X-linked hypophosphatemia

X-linked hypophosphatemia (XLH) is a rare inherited disorder characterized by elevated levels of FGF23, chronic hypophosphatemia, impaired bone mineralization, and chronic long-term manifestations. Treatment for XLH has been mainly focused on normalizing its biochemical abnormalities. Despite treatment, patients with XLH often present impaired physical function and decreased quality of life (QoL). We hypothesize that physical functionality and QoL are more strongly associated with chronic pain and decreased muscle mass than persistent biochemical abnormalities or exposure to conventional treatment. We conducted an observational, cross-sectional study with patients with XLH. Clinical records and biochemical parameters were assessed. QoL surveys SF36v.2 and WOMAC were applied. Functional status was measured by a physiatrist and an occupational therapist. Appendicular lean mass (ALM) was measured and compared with age and sex-matched healthy controls. Enthesopathies and osteoarthritis were evaluated. Pain was assessed using the Brief Pain Inventory, the Visual Analog Scale, and the Doleur Neuropathique-4 scales. Muscle strength was evaluated by the quadriceps muscle isometric strength (QMS) and physical performance with the 6-Minute Walk Test (6MWT) and the Functional Independence Measure (FIM) scale. A total of 30 patients were included: 21 females; median age of 32 yr. All participants had significant functional deficits, chronic pain, and reduced QoL. Limitations in daily activities were significantly associated with higher severity of pain, decreased ALM, lower QMS, and less distance in 6MWT (p < .05). Neither FIM scale, phosphate levels, FGF23, nor the lifetime exposure to conventional treatment was associated with these functional variables. In conclusion, impaired physical functionality in patients with XLH was associated with lower muscle mass, lower muscle strength, and severe chronic pain. These findings highlight the importance of, in addition to optimizing the biochemical control of the disease, expanding patient care including pain prevention and management as well as comprehensive physical therapy and rehabilitation.

Is gastroesophageal reflux disease a comorbidity of burning mouth syndrome? A cross-sectional, real-world study

BackgroundThe etiology of burning mouth syndrome (BMS) patients remains unclear and systemic conditions concurrently with BMS are viewed with greater scrutiny. The present study aimed to reveal whether gastroesophageal reflux disease (GERD) is the possible comorbidity of BMS.MethodsIn our study, a real-world design was employed, enrolling BMS patients from an oral medicine clinic and capturing data in a non-interventional, cross-sectional setting. Endoscopy and the Gastroesophageal Reflux Disease Questionnaire (GERDQ) were used to assess the potential GERD patients. Demographics, clinical symptoms and signs were compared between both the GERD and non-GERD groups, and GERDQ ≥8 and <8 groups. Meanwhile, GERDQ items were assessed to determine predictive value.ResultsIn total, 124 BMS patients with GERDQ scores were enrolled, of whom 84 patients were screened by endoscopy. GERD were confirmed by endoscopy in 30.95% (26/84) of patients with BMS, whereas 69.05% (58/84) showed no definite evidence of GERD. When GERDQ with a cutoff score of 8 was utilized for screening all 124 BMS patients, 25.8% (32/124) had GERDQ scores ≥8. When considering the endoscopic diagnosis as the golden standard due to the low availability of 24-h pH monitoring, the specificity and sensitivity were 79.2% and 46.2% respectively. Clinically, altered taste (p = 0.022) and thickened tongue coating (p = 0.001) were significantly more common in the GERDQ ≥8 group, whereas no significant difference was revealed between endoscopy approved GERD and non-GERD groups.ConclusionsGERD may represent a potential systemic comorbidity in BMS patients and GERDQ might serve as the screening tool assisting healthcare professionals. Altered taste and thickened tongue coating might be suggestive for potential GERD symptoms in BMS patients. Further research is desired to elucidate the mechanisms linking such conditions.

Association of chronic pain with frailty and pre-frailty in older adults: A systematic review and meta-analysis

PURPOSE

Frailty has been demonstrated to correlate with chronic pain (CP). This study aimed to estimate the risk of frailty/pre-frailty and evaluate the potential bidirectional relationship between frailty/pre-frailty and CP.

METHODS

A systematic search was conducted across ten databases, covering literature from their inception through November 23, 2024. Two independent reviewers screened relevant studies, assessed study quality, and extracted data. All analyses were performed using R software, version 4.3.1.

RESULTS

A total of 25,904 participants aged ≥ 60 years were included in 33 studies. CP significantly increased the risk of frailty (OR = 1.91, 95 % CI: 1.47-2.47; I2 = 82 %, p < 0.01), whereas no significant association was found between frailty/pre-frailty and CP risk (OR = 1.52, 95 % CI: 0.66-3.50; I2 = 98 %, p < 0.01). Eleven studies were classified as high quality, and the remainder as moderate quality.

CONCLUSIONS

No evidence supports a bidirectional relationship between frailty/pre-frailty and CP. Nonetheless, addressing and managing CP in older adults may mitigate the risk of frailty and promote healthy aging.

Differences in the clinical presentation of chronic whiplash-associated disorders and nontraumatic neck pain: a systematic review and meta-analysis

ABSTRACT

Health outcomes may be worse for individuals with whiplash-associated disorders (WAD) compared to nontraumatic neck pain (NTNP), and clinical characteristics may differ. This systematic review examined evidence comparing WAD and NTNP in terms of pain, disability, psychological status, quality of life, measures of nociceptive processing, movement, sensorimotor, and muscle function. Studies were identified through electronic database searches and included after screening against predefined eligibility criteria. Standardized mean differences (SMD) or mean differences (MD) and 95% confidence intervals (CI) were calculated. Associations between MDs with demographics and study characteristics were explored using meta-regression. Certainty of evidence was assessed using Grades of Recommendation, Assessment, Development, and Evaluation. Sixty-one studies were eligible with 45 included in meta-analysis. Individuals with WAD reported clinically relevant higher disability (100-point Neck Disability Index MD [95% CI] 11.15 [8.63, 13.68]), greater remote cold sensitivity (SMD 0.89 [0.57, 1.21]), lower quality of life (SMD -0.96 [-1.77, -0.16]), greater depression (SMD 0.60 [0.27, 0.93]), greater local (SMD -0.56 [-1.00, -0.13]) and remote (SMD -0.50 [-0.81, -0.19]) pressure sensitivity, less cervical flexion (MD -5.30° [-7.44, -3.16]) and extension (MD -5.43° [-9.31, -1.55]), higher pain intensity (100-point numerical rating scale: MD 8.15 [5.80, 10.50]), and greater kinesiophobia (SMD 0.35 [0.11, 0.59]). No between-group differences were found for dizziness symptoms, stress, anxiety, balance, and local cold sensitivity. Meta-regression indicated that disability differences were negatively associated with age (R2 = 29.6%, P = 0.006). Certainty of evidence was mostly moderate. Individuals with chronic WAD have a worse clinical presentation compared to those with chronic NTNP, which has implications for patient assessment and management.

Fatigue, sleep disturbance, and pain interference in children and adolescents with chronic pain: a longitudinal study

ABSTRACT

Research has shown that pain and sleep disturbance often co-occur and influence each other over time in children and adolescents with chronic pain. Longitudinal studies examining the underlying mechanisms of this association are scarce and have focused primarily on the role of internalizing mental health symptoms and mood. This longitudinal study aimed to determine whether fatigue underlies the co-occurrence and mutual maintenance of sleep disturbance and pain over time in children and adolescents with chronic pain. Participants were 355 school-aged children and adolescents (mean age = 11.63 year old; 67% female) with chronic pain. The participants provided sociodemographic information and responded a survey that included measures of pain (duration, intensity, interference), sleep disturbance, and fatigue at first assessment and 12 months later. Partially latent, cross-lagged, panel, structural equation models revealed that sleep disturbance, pain intensity, and pain interference co-occurred at both time points. Higher levels of sleep disturbance, pain intensity, and pain interference at first assessment predicted higher levels of sleep disturbance, pain intensity, and pain interference at follow-up, respectively. Higher levels of pain interference at first assessment predicted higher levels of sleep disturbance at follow-up while controlling for initial levels of sleep disturbance. Furthermore, fatigue was found to mediate the association between first assessment and follow-up sleep disturbance, the association between first assessment and follow-up pain interference, and the association between first assessment pain interference and follow-up sleep disturbance. The findings highlight the need to assess and address fatigue in children and adolescents with chronic pain and sleep disturbance.

Interpersonal dynamics in chronic pain: The role of partner behaviors and interactions in chronic pain adjustment

Chronic pain affects one-third of adults globally, leading to significant disability and healthcare costs. This review highlights the role of interpersonal processes in chronic pain adjustment, focusing on how partner behaviors and interactions influence patient well-being and functioning. It synthesizes recent theoretical perspectives and empirical findings, discussing both potentially maladaptive responses, such as solicitousness and invalidation, and adaptive behaviors, including validation of emotional disclosures and encouragement of valued activities. The review identifies gaps in current research, emphasizing the need for clearer conceptualizations of partner behaviors, advanced methodological approaches to capture dynamic interactions, and robust measurement tools. Prioritizing couple interventions that enhance communication, relational dynamics, and partner support for functional autonomy may lead to more holistic and effective chronic pain management.

Chronic pain in European adult populations: a systematic review of prevalence and associated clinical features

ABSTRACT

Chronic pain (CP) is a multifaceted and severely disabling persistent condition that affects individuals worldwide. A synthesis of epidemiological data is still lacking. The present systematic review aims at presenting point, period, and lifetime prevalence estimates of CP in the European adult population, as well as relevant features associated with it. Following PRISMA guidelines, a systematic search in PubMed, Web of Science, Embase, and Cochrane library was run from inception to May 2024, resulting in 39,832 hits. Among those, 132 full-text articles were assessed, and 23 studies comprising 862,013 participants with CP were included. The Joanna Biggs Institutes' Critical Appraisal Checklist for Studies Reporting Prevalence Data (JBI) was used for quality assessment. Findings showed a point prevalence ranging from 12% to 48%, a 6-month prevalence of 17.5% to 49.8%, a 12-month prevalence ranging from 8.1% to 44.6%, and a lifetime prevalence ranging from 12.7% to 33.7% independently from sex. Sociodemographic factors (eg, female sex, higher age, no partnership, lower education, unemployment) and clinical features (eg, medical diseases, mental disorders and burdens, healthcare utilization, functional impairment) were identified as being associated with CP. The variability in prevalence estimates can be reduced by applying consistent diagnostic criteria (eg, ICD-11) and by using standardized assessment tools (eg, scales, clinical interview). The high prevalence and the characteristics of the associated features support the need for adequate, multicomponent care paths to manage CP based on a comprehensive biopsychosocial model.

Occupational therapy in pain management: An exploration and description of current UK practice

Introduction

There is a growing body of evidence regarding the contribution to the management of chronic pain by occupational therapists. However, there is limited research available regarding contemporary practice in the United Kingdom (UK).

Method

An on-line questionnaire was circulated via social media, profession specific publications and specialist interest groups. Responses were requested from UK-based Health and Care Professions Council registered occupational therapists who identified working with those living with chronic pain and their friends, family and supporters.

Findings

A total of 26 occupational therapists responded. Occupational therapists are working in diverse service settings, offering a range of interventions and recognised the unique contribution by occupational therapists to this area of practice. Perceived barriers to delivering intervention included staffing levels, understanding of the occupational therapists' role and suggestions for additional interventions were stated.

Conclusion

This research increases understanding of UK-based occupational therapist's current practice in pain management and views of their role. It provides considerations for further research including how to increase awareness of occupational therapy's contribution to this area of practice, exploring the occupational needs of individuals and those of friends, family and supporters to ensure intervention is designed to best meet the needs of this population.

Pressure pain sensitivity is independent of structural pathology in patients with subacromial pain syndrome: a cross-sectional analysis

OBJECTIVE

To compare localized (primary) and widespread (secondary) hyperalgesia through the measurement of the pressure pain threshold (PPT) of patients with normal imaging findings, rotator cuff tear, or other pathologies.

DESIGN

This was a cross-sectional design with data collected at a single time point.

SETTING

This study was performed at 2 large, urban, academic medical centers.

SUBJECTS

The included participants had had chronic subacromial pain syndrome for 3 months or longer. Each participant was categorized into 1 of 3 imaging groups: normal imaging, rotator cuff tear, or other structural pathology.

METHODS

Primary hyperalgesia was assessed with PPT at the midsection of the painful shoulder's lateral deltoid. Secondary hyperalgesia was assessed with PPT at the contralateral tibialis anterior muscle (TA). Analysis of variance (ANOVA) and analysis of covariance (ANCOVA) were performed for each objective. ANCOVA covariates included age, sex, education level, and pain duration.

RESULTS

The 103 participants included 55 males and had a median age of 55 years, a median pain duration of 14.0 months, and a median composite Shoulder Pain and Disability Index (SPADI) score of 43.1%. The ANCOVA for primary hyperalgesia showed no significant difference in square-root-adjusted deltoid PPT among imaging groups (F = 1.04, P = .3589). The ANCOVA for secondary hyperalgesia showed no significant difference in log-adjusted TA PPT among imaging groups (F = 0.24, P = .7900).

CONCLUSIONS

No significant difference was observed in the analysis of ipsilateral deltoid or contralateral TA PPT among patients with differing structural shoulder pathologies. These findings suggest that the 3 types of structural shoulder abnormalities we examined are not significantly associated with differences in one measure of hyperalgesia.

TRIAL REGISTRATION

ClinicalTrials.gov ID NCT03752619.

New generation capsaicin-diclofenac containing, silicon-based transdermal patch provides prolonged analgesic effect in acute and chronic pain models

OBJECTIVE

Pain is one of the major public health burdens worldwide, however, conventional analgesics are often ineffective. Capsaicin-the active compound of Capsicum species, being responsible for their pungency-has been part of traditional medicine long ago. Capsaicin is a natural agonist of the Transient Receptor Potential Vanilloid 1 receptor-localized on capsaicin-sensitive sensory neurons and strongly involved in pain transmission-, and has been in focus of analgesic drug research for many years. In this study, we aimed to develop a sustained release transdermal patch (transdermal therapeutic system, TTS) combining the advantages of low-concentration capsaicin and diclofenac embedded in an innovative structure, as well as to perform complex preclinical investigations of its analgesic effect.

METHODS

Drug delivery properties of the TTS were investigated with Franz cell and flow-through cell tests. Analgesic effect of the TTS was examined in in vivo models of acute postoperative and inflammatory, chronic neuropathic and osteoarthritic pain.

RESULTS

Modified silicone polymer matrix-based TTS containing low-concentration capsaicin and diclofenac has been developed, releasing both compounds according to zero-order kinetics. Moreover, capsaicin and diclofenac facilitated the liberation of each other. Combined TTS significantly reduced acute postoperative and inflammatory pain, as well as chronic neuropathic and osteoarthritic pain. Interestingly, in acute postoperative and chronic osteoarthritic pain, capsaicin prolonged and potentiated the pain-relieving effect of diclofenac.

CONCLUSIONS

New generation combined low-concentration capsaicin-diclofenac containing TTS can be an effective therapeutic tool in acute and chronic pain states involving neuropathic and inflammatory components.

Kratom Alkaloids, Cannabinoids, and Chronic Pain: Basis of Potential Utility and Role in Therapy

Introduction: Chronic neuropathic pain is as a severe detriment to overall quality of life for millions of Americans. Current pharmacological treatment options for chronic neuropathic pain are generally limited in efficacy and may pose serious adverse effects such as risk of abuse, nausea, dizziness, and cardiovascular events. Therefore, many individuals have resorted to methods of pharmacological self-treatment. This narrative review summarizes the existing literature on the utilization of two novel approaches for the treatment of chronic pain, cannabinoid constituents of Cannabis sativa and alkaloid constituents of Mitragyna speciosa (kratom), and speculates on the potential therapeutic benefits of co-administration of these two classes of compounds. Methods: We conducted a narrative review summarizing the primary motivations for use of both kratom and cannabis products based on epidemiological data and summarize the pre-clinical evidence supporting the application of both kratom alkaloids and cannabinoids for the treatment of chronic pain. Data collection was performed using the PubMed electronic database. The following word combinations were used: kratom and cannabis, kratom and pain, cannabis and pain, kratom and chronic pain, and cannabis and chronic pain. Results: Epidemiological evidence reports that the self-treatment of pain is a primary motivator for use of both kratom and cannabinoid products among adult Americans. Further evidence shows that use of cannabinoid products may precede kratom use, and that a subset of individuals concurrently uses both kratom and cannabinoid products. Despite its growing popularity as a form of self-treatment of pain, there remains an immense gap in knowledge of the therapeutic efficacy of kratom alkaloids for chronic pain in comparison to that of cannabis-based products, with only three pre-clinical studies having been conducted to date. Conclusion: There is sufficient epidemiological evidence to suggest that both kratom and cannabis products are used to self-treat pain, and that some individuals actively use both drugs, which may produce potential additive or synergistic therapeutic benefits that have not yet been characterized. Given the lack of pre-clinical investigation into the potential therapeutic benefits of kratom alkaloids against forms of chronic pain, further research is warranted to better understand its application as a treatment alternative.

Maternal Chronic Physical Conditions and Alcohol and Substance Use Disorders in the Preconception and Perinatal Periods

Background: Chronic physical conditions (CPC) and alcohol and substance use disorders (SUD) frequently co-occur, but this has not been examined perinatally. We explored the combined effects of CPC and prepregnancy SUD on perinatal SUD-related adverse events and outpatient care. Materials and methods: This population-based study comprised 77,474 people with and 664,751 without CPC with a birth in Ontario, Canada, 2013-2020. We measured the prevalence of prepregnancy SUD in both groups. We then calculated adjusted relative risks (aRR) of: (1) SUD-related adverse events (toxicity resulting in acute care use/death, or other SUD-related acute care use) and (2) outpatient care for SUD between conception and 365 days postpartum, comparing individuals with prepregnancy CPC and SUD (CPC + SUD), and those with CPC or SUD alone, to those with neither condition. Finally, adjusted relative excess risk due to interaction (aRERI) was calculated to quantify excess risk of the outcomes associated with CPC + SUD, wherein RERI > 0 indicated positive interaction. Results: aRRs of perinatal SUD-related adverse events were 26.79 (95% confidence interval [CI]: 23.12, 31.04) for people with CPC + SUD, 22.09 (95% CI: 19.59, 24.91) for SUD alone, and 2.01 (95% CI: 1.78, 2.27) for CPC alone-each relative to neither condition. There was evidence of positive interaction for CPC + SUD (aRERI: 3.69, 95% CI: 1.13, 6.46). Similar elevated aRRs were observed for perinatal outpatient care for SUD, but without a positive interaction for people with CPC + SUD. Conclusion: As people with both CPC and SUD have the highest risk of perinatal SUD-related adversity, they may need greater preconception and perinatal support.

Single-cell characterization of the human C2 dorsal root ganglion recovered from C1-2 arthrodesis surgery: implications for neck pain

Neurons in the dorsal root ganglion (DRG) receive and transmit sensory information from the tissues they innervate and from the external environment. Upper cervical (C1-C2) DRGs are functionally unique as they receive input from the neck, head, and occipital cranial dura, the latter two of which are also innervated by the trigeminal ganglion (TG). The C2 DRG also plays an important role in neck pain, a common and disabling disorder that is poorly understood. Advanced transcriptomic approaches have significantly improved our ability to characterize RNA expression patterns at single-cell resolution in the DRG and TG, but no previous studies have characterized the C2 DRG. Our aim was to use single-nucleus and spatial transcriptomic approaches to create a molecular map of C2 DRGs from patients undergoing arthrodesis surgery with ganglionectomy. Patients with acute (<3 months) or chronic (≥3 months) neck pain were enrolled and completed patient-reported outcomes and quantitative sensory testing prior to surgery. C2 DRGs were characterized with bulk, single nucleus, and spatial RNA sequencing technologies from 22 patients. Through a comparative analysis to published datasets of the lumbar DRG and TG, neuronal clusters identified in both TG and DRG were identified in the C2 DRG. Therefore, our study definitively characterizes the molecular composition of human C2 neurons and establishes their similarity with unique characteristics of subsets of TG neurons. We identified differentially expressed genes in endothelial, fibroblast and myelinating Schwann cells associated with chronic pain, including FGFBP2, C8orf34 and EFNA1 which have been identified in previous genome and transcriptome wide association studies (GWAS/TWAS). Our work establishes an atlas of the human C2 DRG and identifies altered gene expression patterns associated with chronic neck pain. This work establishes a foundation for the exploration of painful disorders in humans affecting the cervical spine.

State of the art in EEG signal features of mindfulness-based treatments for chronic pain

A systematic review of electroencephalographic (EEG) correlates of Mindfulness- based treatment for chronic pain is presented. Recent technological advances have made EEG acquisition more accessible and also reliable. EEG monitoring before, during, and after treatment might support efficacy assessment and enable real- time adaptive intervention. The preliminary research extracted 131 papers from 6 scientific search engines. The application of the exclusion criteria led to the selection of 4 papers, indicating that the topic is still unexplored and further investigations are required. The collected papers exhibited great variability making challenging the comparison, nevertheless promising EEG correlates emerged. In particular, pain-related evoked potentials correlate with Mindfulness-Based treatment. EEG source analysis revealed the prevalent involvement of regions modulating emotional responses. In addition, higher baseline theta power was associated with greater improvement in depression when Mindfulness-based treatments are administered. This last result makes EEG also suitable for evaluating which patients can benefit most from mindfulness-based treatments.

Predicting Clinical Outcomes at the Toronto General Hospital Transitional Pain Service via the Manage My Pain App: Machine Learning Approach

Background

Chronic pain is a complex condition that affects more than a quarter of people worldwide. The development and progression of chronic pain are unique to each individual due to the contribution of interacting biological, psychological, and social factors. The subjective nature of the experience of chronic pain can make its clinical assessment and prognosis challenging. Personalized digital health apps, such as Manage My Pain (MMP), are popular pain self-tracking tools that can also be leveraged by clinicians to support patients. Recent advances in machine learning technologies open an opportunity to use data collected in pain apps to make predictions about a patient's prognosis.

Objective

This study applies machine learning methods using real-world user data from the MMP app to predict clinically significant improvements in pain-related outcomes among patients at the Toronto General Hospital Transitional Pain Service.

Methods

Information entered into the MMP app by 160 Transitional Pain Service patients over a 1-month period, including profile information, pain records, daily reflections, and clinical questionnaire responses, was used to extract 245 relevant variables, referred to as features, for use in a machine learning model. The machine learning model was developed using logistic regression with recursive feature elimination to predict clinically significant improvements in pain-related pain interference, assessed by the PROMIS Pain Interference 8a v1.0 questionnaire. The model was tuned and the important features were selected using the 10-fold cross-validation method. Leave-one-out cross-validation was used to test the model's performance.

Results

The model predicted patient improvement in pain interference with 79% accuracy and an area under the receiver operating characteristic curve of 0.82. It showed balanced class accuracies between improved and nonimproved patients, with a sensitivity of 0.76 and a specificity of 0.82. Feature importance analysis indicated that all MMP app data, not just clinical questionnaire responses, were key to classifying patient improvement.

Conclusions

This study demonstrates that data from a digital health app can be integrated with clinical questionnaire responses in a machine learning model to effectively predict which chronic pain patients will show clinically significant improvement. The findings emphasize the potential of machine learning methods in real-world clinical settings to improve personalized treatment plans and patient outcomes.

Assessing pain levels and quality of life in peritoneal dialysis patients: a cross-sectional study

BACKGROUND

End-stage renal disease is a significant global health issue, and Peritoneal Dialysis (PD) is a vital treatment modality. The study aims to assess the Quality of Life (QoL) and pain levels in PD patients and explore potential influencing factors.

METHODS

A cross-sectional study was conducted in 2022 involving 76 PD patients at a referral tertiary dialysis center in Palestine. The study evaluated patient demographics, clinical data, laboratory measures, quality of life as assessed by the KDQOL-SF36, and pain levels as determined by the Brief Pain Inventory. Statistical analyses, including multivariate linear regression, were employed to identify relevant associations.

RESULTS

This study included 76 PD disease patients, with 68.4% being under the age of 60 and 53.9% being male. Almost one-third of the participants (34.0%) reported mild to severe pain, and 23.7% reported low to high interference levels. Pain severity was negatively correlated with supplement doses for both vitamin D3 (p = 0.049) and calcium (p < 0.01). Female patients reported higher pain severity (p = 0.001) and interference (p < 0.007) levels. The study revealed relatively higher QoL among our cohort of PD patients compared to previously published findings in similar settings, specifically for HD populations. Factors such as age, comorbid conditions, and duration of dialysis influenced QoL (p < 0.05). Pain severity and interference were negatively correlated with QoL (p = 0.01).

CONCLUSION

This study provides valuable insights into the QoL and pain experiences of PD patients in Palestine. It underscores the importance of effective pain management strategies and holistic care to improve QoL in this patient population. Addressing psychological and emotional well-being is vital for optimizing treatment adherence and long-term outcomes.

CLINICAL TRIAL NUMBER

Not applicable.

Mourning for Silence: Bereavement and Tinnitus-A Perspective

Tinnitus is defined as the conscious awareness of a tonal or composite noise for which there is no identifiable corresponding external acoustic source, which becomes tinnitus disorder when the phantom sound is associated with suffering and/or disability. There is only limited knowledge about the time course of tinnitus disorder. Bereavement science has identified four different trajectories: resilience, recovery, chronic, and delayed. The question arises whether these four trajectories exist in tinnitus as well if one considers tinnitus as the loss of silence (at will). To verify whether these four trajectories exist, short-term tinnitus progression was analyzed retrospectively using an Ecological Momentary Assessment (EMA) approach, extracting the data from patients who started using the TrackYourTinnitus (TYT) app (version 1, Ulm University, 2013) from the start of their tinnitus perception. Four patients were identified retrospectively via the TYT app with acute tinnitus, and the bereavement trajectories were reconstructed based on EMA. In conclusion, this perspective suggests that the four known bereavement trajectories may exist in tinnitus, and prospective evaluations of larger samples are warranted to confirm or disprove this analogy between bereavement and tinnitus, in which tinnitus is conceived as the loss of (controllable) silence.

Long-term lived experiences of patients with chronic pain or angina pectoris treated with spinal cord stimulation: a qualitative study

OBJECTIVE

To explore the short-term and long-term lived experiences of patients with chronic pain and angina pectoris with spinal cord stimulation.

DESIGN

An interpretive qualitative study with thematic analysis of one-off, semistructured interviews, following Braun and Clarke (2006).

SETTING

A multidisciplinary, publicly funded pain service in Auckland, New Zealand. Patients usually undergo a comprehensive medical, psychological and functional assessment and an in-house pain management programme before proceeding to spinal cord stimulator implantation.

PARTICIPANTS

Participants implanted with a spinal cord stimulator between 1998 and 2019 who had their stimulator for ≥1 year, purposively sampled to increase the range of ethnicities.

MAIN OUTCOME

The themes identified from the interviews.

RESULTS

24 participants with chronic pain of varied aetiology and a median (range) of 5.2 (2.4-23.2) years since stimulator implantation participated. 22 participants had the device in situ, and 2 had been explanted. Five main themes were identified: (1) embodiment: stimulator and body as one; (2) technical factors: batteries and type of stimulation; (3) improved well-being; (4) social connection and (5) healthcare system interaction. Most participants reported pain relief, but many had experienced complications and discomfort. They emphasised the importance of ongoing support from the pain service. Acceptance of pain, coping and embodiment emerged as common motifs across these themes. 21 participants were satisfied with their treatment.

CONCLUSION

Within the context of a multidisciplinary pain clinic, despite some discomfort and various complications, most participants valued the ongoing reduction of pain achieved with spinal cord stimulation. Timely access to support from the pain service influenced their experience and satisfaction with their stimulators. Acceptance of pain and embodiment of the stimulator helped participants adapt to living with their stimulator, often over many years.

Non-Cognitive Behavioral Therapy Psychological Interventions May Not Make the Difference in Children and Adolescents With Chronic Pain

Background and Aim

Chronic pain in pediatric populations presents a multifaceted challenge with biopsychosocial impact, requiring a multidisciplinary approach including psychological treatment. At our interdisciplinary pain center, the SARS-CoV-2 pandemic-related disruptions led to the cessation of cognitive-behavioral therapy (CBT) and other psychological interventions during the pandemic. The aim of this retrospective cohort study with secondary retrospective matched case-control analysis was to evaluate the impact of interruption of non-CBT psychological interventions, namely psychoanalysis and psychodynamic psychotherapy, on children and adolescents with chronic pain conditions during the SARS-CoV-2 pandemic.

Materials and Methods

We included pediatric patients with primary and secondary chronic pain conditions evaluated by our team during the SARS-CoV-2 pandemic. We excluded patients who did not receive psychological intervention when available, those with incomplete data on initial evaluation or follow-up, and those who received outside psychiatric care or individual or group CBT. The primary outcome was a Patients' Global Impression of Change (PGIC) score of 6-7. Secondary outcome measures were pain intensity, use of pain medication, sleep, physical function, school attendance, the incidence of suicidality, and the reason for end of treatment.

Results

The study included 146 patients, 77 who received non-CBT psychological interventions and 69 who did not receive any psychological interventions. We found no meaningful difference between the use of non-CBT psychological intervention and no treatment in the incidence of PGIC 6-7 points, pain intensity, school attendance, physical function, suicidality, and cause of end of treatment. Patients not receiving any psychological interventions were more likely to have normalized sleep at the end of treatment.

Conclusion

Non-CBT psychological interventions, namely psychoanalysis and psychodynamic psychotherapy, were not associated with meaningful benefits for children and adolescents with chronic pain during the COVID-19 pandemic. Patients who did not receive psychological interventions reported normalization of their sleep at the end of treatment compared to those who participated in non-CBT interventions.

Association between pain and incident arrhythmias in 422,654 individuals: evidence from the UK Biobank cohort

AIMS

Pain is associated with cardiovascular disease; however, its association with incident arrhythmias is unclear. We assessed associations between different pain characteristics (pain type, chronic pain, chronic widespread pain [chronic widespread pain], chronic musculoskeletal pain [chronic musculoskeletal pain], and number of chronic pain and chronic musculoskeletal pain sites) and incident cardiac arrhythmias, overall and by subtype.

METHODS

The study included 422,654 UK Biobank participants. Pain was ascertained via a touchscreen questionnaire. The outcomes were incident arrhythmias: all cardiac arrhythmias, atrial fibrillation (AF), other (non-AF) cardiac arrhythmias, bradyarrhythmias, and ventricular arrhythmias. Multivariable Cox-proportional regression was used to investigate the associations.

RESULTS

Over a mean (SD) follow-up of 13.19 (1.96) years, 36,860 (8.72%) participants developed arrhythmia. Compared with those without pain, those with chronic localized pain and chronic widespread pain had increased risk of all cardiac arrhythmias (hazard ratio [HR] 1.13, 95% confidence interval [CI], 1.10-1.17; 1.34, 1.19-1.51), AF (1.09, 1.05-1.14; 1.33, 1.15-1.55), and other cardiac arrhythmias (1.17, 1.12-1.22; 1.41, 1.20-1.66). There was evidence of a dose-relationship between number of chronic pain sites and risk of all cardiac arrhythmias, AF and bradyarrhythmias. Effect estimates were significantly larger among participants aged <60 years than those aged ≥60 years, and larger in women than men.

CONCLUSIONS

Chronic pain was associated with cardiac arrhythmias. Whilst causation cannot be assumed in any observational study, there was evidence of both a temporal relationship and dose-relationship. These findings reinforce the need for pain management approaches that include a broad assessment of individuals' risk factors, wider health status, and appropriate vigilance for emerging conditions.

Pain Intensity and Pain Catastrophizing Among Patients with Chronic Pain: The Mediating Effect of Self-Efficacy

Aim

This study aimed to explore the mediating role of sense of self-efficacy in the relationship between pain intensity and pain catastrophizing among chronic pain patients.

Methods

A questionnaire survey was administered to patients with chronic pain at the pain intervention departments of three tertiary hospitals in Shaanxi Province between July 2023 and July 2024. The visual analogue scale, chronic pain self-efficacy scale, and pain catastrophizing scale were used to assess the patients' pain intensity, self-efficacy, and pain catastrophizing degree, respectively. SPSS 27.0 and Mplus 8.3 software were used for statistical analysis.

Results

This study included a total of 430 patients with chronic pain. The average score for catastrophizing pain among participants was 22.76 (score range 0-52), which is considered moderate. Pain intensity and pain catastrophizing were significantly and positively correlated, and the findings found that chronic pain self-efficacy mediated the correlation between pain intensity and pain catastrophizing after controlling for sociodemographic and disease-related variables. In addition, chronic pain self-efficacy was found to be an important mediator, accounting for 32.5% of the total effect.

Conclusion

Among patients with chronic pain, chronic pain self-efficacy explains the relationship of pain intensity and pain catastrophizing. These findings imply that interventions that decrease pain intensity and increase patients' sense of self-efficacy are beneficial for improving pain catastrophizing in this population.

International Classification of Diseases-11 chronic pain severity specifiers for children and adolescents: a validation study

ABSTRACT

The 11th revision of the International Classification of Diseases (ICD-11) now includes separate chronic pain diagnoses that may be extended by chronic pain severity specifiers. These specifiers comprise 3 dimensions-pain intensity, pain-related distress, and pain-related interference-rated on an 11-point numerical rating scale referring to the past 7 days. Like the chronic pain diagnoses, these specifiers were originally developed for adults. The current study, therefore, aimed to adapt and validate the 3 ICD-11 chronic pain severity specifiers for pediatric chronic pain patients and evaluate their clinical utility. After adapting the specifiers using feedback from patients and experts, data were collected from N = 319 pediatric chronic pain patients aged 8 to 17 years in a tertiary care setting using 4 assessment methods: patient interview, patient questionnaire, parent-proxy, and healthcare-professional-proxy. Despite all patients having chronic pain, not all reported having experienced pain in the past 7 days. The 3 severity dimensions were interrelated but not unidimensional; both interrater and test-retest reliability were large. While patterns of concurrent and discriminant validity were as expected, correlations with related measures were small. Predictive validity regarding treatment recommendation was small to medium. Most, but not all, suggested severity categories ("none," "mild," "moderate," "severe") were sufficiently distinct within this sample. The chronic pain specifiers provide a quick and easy biopsychosocial description. They should, however, be interpreted with caution in clinical practice, as the psychometric quality is insufficient for making therapeutic or reimbursement-related decisions for individual pediatric patients based solely on these 3 items.

Spinal Cord Stimulation Explantation and Chronic Pain: A Systematic Review and Technology Recommendations

Background

Chronic pain affects 20.5% of the US population, costing $296 billion annually in lost productivity. Spinal cord stimulation (SCS) has become a key treatment for refractory neuropathic and nociceptive pain, with increasing usage due to technological advancements. However, the durability of SCS therapy, including explantation rates, remains a concern. Understanding explantation causes is essential for improving patient selection and device effectiveness. This study aims to analyze SCS explantation rates and reasons, as well as evaluate the financial burden of these procedures on the healthcare system.

Methods

Three primary screening methods were used: manual search with keywords, MeSH term query, and reference list screening. The search covered PubMed, Cochrane, and Web of Science databases from inception to November 2024, yielding 719 articles. After applying eligibility criteria, 72 articles were identified, and 25 were selected for analysis. Data extraction was done by independent reviewers, with a second reviewer ensuring accuracy. Discrepancies were resolved by the corresponding editor.

Results

We reviewed data from 13,026 patients who underwent permanent SCS implantation between 1984 and 2024, across 25 studies. A total of 1882 patients (9.82%) underwent explantation. The most common reason was lack of efficacy and inadequate pain relief (38%), followed by lead failure (15%) and infection (14%). While SCS is generally effective, issues related to device longevity and patient satisfaction persist, with explantation rates due to technical failures and lack of efficacy being concerns.

Conclusion

SCS efficacy varies, with explantation rates reaching up to 38%, often due to inadequate pain relief. Most explantations occur within the first year, despite SCS being a safe and effective treatment. High implantation costs ($35,000 to $70,000) and revision costs ($15,000 to $25,000) raise concerns among payors. The hardware-driven model limits waveform flexibility, highlighting the need for innovation.

[Status survey of Austrian pain clinics 2023 : Impact of the COVID-19 pandemic on pain management services]

BACKGROUND

According to a 2020 report by the Austrian Pain Society (ÖSG), between 1.5 and 1.8 million people in Austria suffer from chronic pain. For the treatment of these patients, multimodal pain therapy in specialized pain therapy facilities should be considered. This study aimed to analyze the actual postpandemic state of care in pain clinics in 2022 and to show how it has changed in recent years.

METHODS

In our survey, the heads or employees of all anesthesiology departments in Austria were asked via SurveyMonkey (SurveyMonkey Inc., San Mateo, CA, USA) using an access code to compare the pre- to postpandemic status of their pain clinics. Only anesthesiology departments were contacted, as pain clinics in Austria are almost entirely run by them. This survey was sent online by email to the heads of Austrian hospitals with an existing pain clinic and was open for completion from autumn 2022 to May 2023.

RESULTS

Of the 109 surveyed clinics, 92 participated in our study. Only 51 currently operate a pain clinic, seven of which are full-time. Nine pain clinics had closed since 2014, while seven new ones have opened. According to our data, only one specialized hospital and two basic care hospitals offer multimodal pain therapy. Invasive procedures were used more often compared to multimodal pain therapy.

CONCLUSION

Despite the nominal increase of pain clinics in Austria, there is a multifactorial discrepancy between the recommendation of the Austrian Pain Society and the actual care of patients with chronic pain in Austria. Administrative and personnel obstacles must be overcome to meet the needs of this patient group. In addition, efforts to increase the interest of physicians in chronic pain management are needed. Greater support from healthcare policies and effective integration of pain clinics into the healthcare system could help improve the care situation.

Association of visceral adiposity index and chronic pain in US adults: a cross-sectional study

The Visceral Obesity Index (VAI) is utilized as a metric employed to assess the distribution of abdominal adipose tissue as well as the functional status of adipose tissue. Nevertheless, the interplay between VAI and persistent pain has yet to be investigated. This cross-sectional analysis investigated the relationship between VAI and persistent pain among 1357 American adults from NHANES data. A logarithmic transformation of VAI was performed to adjust for skewness. Following the adjustment for relevant variables, logistic regression analysis showed a noteworthy association between VAI and chronic pain, suggesting that higher VAI values may be linked to an increased prevalence of persistent pain. Curve fitting analysis revealed a nonlinear correlation, with a breakpoint at a VAI value of 0.18. For VAI values below this threshold, each unit increase was notably correlated with an elevated prevalence of persistent pain, while increases in VAI beyond this threshold did not show a significant impact on chronic pain prevalence. Subgroup analyses indicated that the VAI may serve as a relatively independent risk factor for persistent pain. These findings highlight the possibility of incorporating abdominal adipose modification into pain management approaches and emphasize the critical importance of monitoring visceral fat accumulation to better identify patients more susceptible to chronic pain.

The association between chronic pain and metabolic syndrome: A scoping review

Metabolic syndrome (MetS) is a prevalent comorbidity in patients with chronic pain conditions. Emerging evidence suggests that the relationship between MetS and chronic pain is bidirectional. This interplay involves complex mechanisms, including proinflammatory mediators in nociceptive modulation and pain-induced lifestyle changes affecting metabolic function. This scoping review examines the association between MetS and chronic pain. We conducted a scoping review, including 28 studies. This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidelines. We included observational studies (cross-sectional, case-control, and cohort studies) from the following databases: Ovid MEDLINE, EMBASE, Cochrane Central, Cochrane Database of Systematic Reviews, and Scopus. We identified studies on migraine (n = 9), spinal pain (n = 8), general chronic pain (n = 4), fibromyalgia syndrome (n = 3), carpal tunnel syndrome (n = 1), osteoarthritis (n = 1), shoulder pain (n = 1), and neuropathic pain (n = 1). Most studies used a cross-sectional design and standard criteria to define MetS, with some exceptions. Individuals with MetS and spinal pain, fibromyalgia, or general chronic pain showed higher pain scores and increased functional limitations. MetS was common in patients with migraine, but its effect on pain severity was inconclusive. The relationship between MetS and other pain conditions requires further investigation to clarify the association and potential mechanisms. MetS is prevalent in patients with chronic pain and is associated with worse pain and functional outcomes. Health care providers should acknowledge the wide spectrum of MetS beyond obesity. This understanding may help identify those at risk for more severe chronic pain.

Chronic postsurgical pain in the ICD-11: implications for anaesthesiology and pain medicine

Chronic postsurgical pain (CPSP) is associated with reduced health-related quality of life and disability. In some patients, it can result in long-term opioid use even after minor surgery. Epidemiological studies have reported highly varying rates of CPSP, largely because researchers have used different definitions with self-defined cut-offs for pain scores. With the introduction of the 11th revision of the World Health Organisation International Classification of Diseases and Related Health Problems (ICD-11), chronic pain is now recognised as an entity of its own, its biopsychosocial nature is emphasised, and its definition is standardised. Compared with the ICD-11 definition, the prevalence of CPSP might have been overestimated in previous studies. The ICD-11 provides a multifactorial assessment of pain severity, referring to pain intensity, pain-related interference, and pain-related distress, which cover the biopsychosocial aspects of chronic pain. These three scores can be added as extension codes to any pain diagnosis. Harmonisation of the CPSP criteria within the different coding levels of the ICD-11 might improve discrimination of CPSP from other chronic pain conditions not induced by surgery. Although neuropathic CPSP increases pain severity and requires alternative therapeutic approaches to nociceptive pain, a specific code to differentiate between neuropathic and non-neuropathic CPSP is not available. For clinical practice and research, the evidence-based ICD-11 definition, which provides clear-cut diagnostic criteria, should generally be used instead of pain scores alone. This will improve the comparability of data, form the basis for future diagnostic and therapeutic approaches, and facilitate communication.

Linking physical activity to workers' low back pain, back health, and theory-based psychological variables: study protocol of the workHealth intensive longitudinal observational study

BACKGROUND

The high prevalence of low back pain (LBP) in today's working population and its substantial impact on quality of life call for preventive and sustainable strategies. Physical activity (PA), especially during leisure-time (LTPA), has been proposed as one of the few promising, active preventive measures against the onset of LBP. This is the protocol for the prospective observational study workHealth that aims to describe the patterns of PA among workers (including back posture and movement), examine the link between PA, LBP and back health and identify theory-based psychological determinants of LTPA.

METHODS

The proposed study is a longitudinal observational study taking place over 2 months with an intensive-longitudinal ecological momentary assessment (EMA) phase. A sample of 252 adults will be recruited from two working populations, sedentary workers, and manually working physiotherapists. At baseline, participants complete a self-report questionnaire and undergo an objective measurement of their back posture and mobility. At 2, 4, and 8 weeks after baseline, participants fill in the follow-up questionnaires. Starting at baseline, participants will also wear an accelerometer and will complete three daily questionnaires for the following 14 days. In addition to the main study, a sub-sample of 8 observational N-of-1 studies will have an extended EMA phase of 68 days and a data-driven exit interview. The primary outcome is moderate-to-vigorous LTPA. Data will be analyzed using regression and multi-level models. For the N-of-1 studies, a mixed-methods approach will be used including dynamic regressions.

DISCUSSION

Rather than solely examining LBP from a pathological perspective, workHealth is one of the first studies to investigate psychological, behavioral and biomechanical risk factors and protective resources against LBP. The study will offer insight into theory-based, psychological determinants of LTPA and its relationship to both low back pain and back health. Between-person and within-person level analyses will provide insight on group comparisons of average effects and individual patterns of physical activity in daily life, respectively. Understanding these relationships can inform future behavioral interventions and ultimately contribute to prevention efforts against LBP and the promotion of back health.

TRIAL REGISTRATION

German Clinical Trials Register DRKS00025296|| https://drks.de/ || Registration date 28/06/2021.

Effect of Mindfulness-Based Stress Reduction on Patients With Chronic Pain: A Randomized Controlled Trial

BACKGROUND

Chronic pain management includes treatment with the use of opioids, electrical stimulation and acupuncture. However, traditional understanding of chronic pain has recently been challenged in light of evidence supporting a key role of psycho-social factors and central sensitization in this population. Mindfulness-based stress reduction (MBSR), focuses on increasing awareness and acceptance of moment-to-moment experiences including difficult emotions and physical discomfort.

OBJECTIVE

To examine the effects of a MBSR on chronic pain patients.

DESIGN

A two-arm, blinding randomized controlled clinical trial with repeated-measures design.

SETTING

One pain management clinic in a general hospital.

PARTICIPANTS

Chronic pain patients (N = 149 patients).

METHODS

The patients were randomly allocated to either psychoeducation (intervention group) or usual care (control group) (N = 75 vs 74 patients per group). The randomization was minimized, taking into account the imbalance between the groups over a number of prognostic clinical and demographic factors. The intervention included an 8-week MBSR program (2 hours per week) in a group format and the MBSR program was performed 2 times (1-2 months after enrollment and 7-8 months after enrollment). Study outcomes included Chronic pain (pain intensity and pain interference) assessed with Brief Pain Inventory (primary outcomes), and other secondary outcomes (i.e., quality of life, adherence to the intervention, mindfulness and self-awareness and drug assumption). We examined the differences at baseline (clinical-demographic data collected at enrollment), at 6 (T1) and 13 months (T2) between the intervention and control groups by means of chi-square and independent samples t tests. Normally distributed measurement data were represented by means and standard deviations.

RESULTS

Participants in the intervention group revealed significantly greater reductions on impact of chronic pain in terms of pain intensity (worst pain in the last 24 hours, p < .001; pain right now, p < .001) and in terms of pain interference (interference with mood, p = .002; interference with normal work, p = .043; interference with relationship with other people, p = .036) at T1, and in terms of pain intensity (worst pain in the last 24 hours, p < .001; pain on average, p =. 013; pain right now, p < .001) and in terms of pain interference (interference with mood, p < .001; Interference with sleep, p < .001) at T2. A significant difference emerged in the perceived quality of life, between two groups at T2 (55.9 vs 58.7, t(133) = - 2.053, p = .044).

CONCLUSIONS

Our study added values on the benefits of patients-focused MBSR to treatment of chronic pain. Future research can evaluate its long-term effects for patients of chronic pain with diverse socio-demographic and pain-related characteristics in a greater sample.

REGISTRATION

Italian Clinical Trial Registry (NCT05843409). Recruitment: April 2023 to April 2024.

Deciphering distinct spatial alterations in N-glycan expression profiles in the spinal cord and brain of male rats in a neuropathic pain model

BACKGROUND

Neuropathic pain is a complex condition resulting from damage or disease in the somatosensory nervous system, causing significant physical and emotional distress. Despite its profound impact, the underlying causes and treatment methods of neuropathic pain remain poorly understood.

METHODS

To better understand this condition, we conducted the first study examining the spatial distribution and dynamic expression changes of N-glycan molecules that play a crucial role in nervous system function and sustainable pain signal transmission across multiple regions of the spinal cord and brain in an experimentally induced neuropathic pain model, using matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI).

RESULTS

Our findings revealed that neuropathic pain induces dynamic changes in N-glycan expression across various regions of the spinal cord and brain. Notably, we discovered distinct glycan profiles between the spinal cord and brain, with N-glycans downregulated in the spinal cord and upregulated in the brain at a time when mechanical allodynia is sustained following spinal nerve ligation (SNL). Significant changes in N-glycan expression were observed in the dorsal laminae IV/V/VI and the ventral horn of the spinal cord. Additionally, marked changes were detected in the contralateral regions of the primary sensory cortex (S1) and the primary sensory cortex hindlimb area (S1HL). Furthermore, we observed significant upregulation of N-glycan expression in the thalamus, anterior cingulate cortex (ACC), and medial prefrontal cortex (mPFC) in both ipsilateral and contralateral regions of the brain.

CONCLUSIONS

Given that N-glycans are implicated in pain processing yet their precise role remains unclear, our study highlights the need to explore N-glycosylation with a more nuanced focus on both the spinal cord and brain. This research provides new insights into the mechanisms of persistent neuropathic pain and lays the groundwork for future studies and the development of targeted therapeutic strategies.

Part I: understanding pain in pigs-basic knowledge about pain assessment, measures and therapy

BACKGROUND

Pigs can suffer from pain due to spontaneously occurring diseases, wounds, injuries, trauma, and physiological conditions such as the farrowing process; however, this pain is often neglected. To increase knowledge and awareness about this phenomenon, the current article presents a scoping review of basic and new approaches for identifying, evaluating, and treating pain in pigs.

METHODS

A scoping review was conducted with results from a search of the electronic database VetSearch and CABI. With regard to eligibility criteria, 49 out of 725 publications between 2015 and the end of March 2023 were included. The findings are narratively synthesized and reported orienting on the PRISMA ScR guideline.

RESULTS

The results of this review showed that practitioners need to consider pain not only as a sign of a disease but also as a critical aspect of welfare. If both the symptoms of pain and the underlying reasons remain unassessed, the longevity and prosperity of pigs may be at risk. In this respect, veterinarians are obliged to know about intricacies of pain and pain mechanisms and to provide adequate treatment for their patients.

CONCLUSION

It is pivotal to increase knowledge about pain mechanisms, the reasons for heterogeneity in behavioural signs of pain, and methods for evaluating whether a pig is experiencing pain. This article will help practitioners update their knowledge of this topic and discuss the implications for everyday practice.

The relationship between leisure time activities and chronic musculoskeletal pain in schoolteachers

BACKGROUND

Leisure activities (LAs) have a positive effect on well-being, healthy aging, cognitive functions, physical function, and mental health.

PURPOSE

To determine the prevalence of chronic musculoskeletal pain (CMSP) in schoolteachers and evaluate the relationship between different types of LAs and CMSP.

METHODS

A total of 433 in-service schoolteachers (303 female, 130 male) participated in this cross-sectional study between January 2023 and March 2023 using an online survey. Common LAs in Turkey, including reading books/magazines/newspapers or writing stories/letters, leisure physical activities (PAs), computer-based LAs, television viewing, LAs on smartphones, music listening, going to the cinema/theatre/opera/ballet/concert, gardening, cooking meal/pastry, meeting with friends, and painting/marbling/ceramic/knitting, and their durations were recorded.

RESULTS

The median age of the participants was 38.0 (IQR, 35.0-45.0) years. The prevalence of CMSP was 44.8%. Multiple logistic regression analysis including age, sex, body mass index, comorbidities, weekly standing duration at work, and LAs showed that there was an inverse relationship between CMSP and PAs (OR = 0.564, 95% CI: 0.357-0.890) and listening to music (OR = 0.555, 95% CI: 0.317-0.973). Moreover, LAs on smartphones (OR = 4.318, 95% CI: 2.004-9.308), gardening (OR = 1.827, 95% CI: 1.097-3.043), and having a thyroid disorder (OR = 2.212, 95% CI: 1.045-4.684) were predictive variables for CMSP.

CONCLUSIONS

Considering that PAs and music listening are inversely associated with CMSP, it may be beneficial to make them a part of the lifestyle of both healthy individuals and individuals with CMSP. Physicians should also be aware that LAs on smartphones carry a greater risk for CMSP.

Self-reported questionnaires assessing body perception disturbances in adults with chronic non-cancer pain: a scoping review

Introduction

Body perception disturbances (BPD) are well documented in certain chronic pain populations [e.g., complex regional pain syndrome (CRPS)], while being far less studied in chronic pain as a general condition. The aims of this scoping review are to identify the self-reported questionnaires used to assess BPD in individuals with chronic non-cancer pain and to refine the definition of the BPD construct as used in these questionnaires.

Methods

A search strategy focusing on the concepts of "chronic pain", "body perception" and "questionnaire" was used across four databases. Each record was screened for eligibility by two independent reviewers, and data extraction was performed by one reviewer and validated by a second reviewer.

Results

Eighty-seven studies were included, comprising 18 different questionnaires-either directly related to BPD or containing relevant items. The three most commonly used questionnaires were the Bath Body Perception Disturbance Scale, the Fremantle Back Awareness Questionnaire, and the Neurobehavioral Questionnaire. Appraisal of the construct derived from the questionnaire items identified five main facets: size, shape, cognitive neglect-like symptoms, proprioceptive awareness, and agency, along with 11 other less frequently addressed facets. The most represented clinical populations were CRPS (40 studies) and chronic low-back pain (20 studies).

Discussion

A variety of self-reported questionnaires are available to assess BPD, but most are diagnosis- or body-region specific. To better assess BPD in individuals with chronic non-cancer pain, a consensus on the general definition and the key facets of the construct is needed.

Correlation Between Pain Intensity and Trunk Sway in Seated Posture Among Office Workers with Chronic Spinal Pain: A Pilot Field-Based Study

This pilot study examines the relationship between pain intensity and trunk sitting postural control in 10 office workers with chronic spinal pain, using field-based real-time inertial sensors. Pain intensity was assessed with the Numeric Pain Rating Scale (NPRS) before and after work across three non-consecutive workdays, while postural control was evaluated through estimated center of pressure (COP) displacements. Linear and nonlinear metrics, including sway range, velocity, the Hurst exponent, and sample entropy, were derived from the estimated COP time series. Pearson correlation coefficients (r) and corresponding p-values were used to analyze the relationship between pain intensity and postural control. Significant correlations, though limited to specific metrics, were found (r = -0.860 to 0.855; p < 0.05), suggesting that higher pain intensity may be correlated with reduced postural variability. These findings provide preliminary insights into the potential link between pain intensity and postural control. Understanding trunk posture dynamics could inform the development of targeted ergonomic interventions to reduce musculoskeletal stress and improve sitting comfort in office environments.

Prevalence of chronic musculoskeletal pain among different occupational groups of a large German chemical company: results of a cross-sectional study

Objectives. This study aimed to examine the prevalence of chronic musculoskeletal pain among employees of a large German chemical company and how it varies depending on occupational group. Methods. Cross-sectional data were collected between 2019 and 2022 during a voluntary occupational health check-up, including a written questionnaire. Chronic musculoskeletal pain was defined as lasting at least 3 months in the past year. Occupational group was operationalized either by self-reported work area or by the International Standard Classification of Occupations 2008 (ISCO-08). Associations between occupational group and chronic musculoskeletal pain were analyzed using robust Poisson regression. Results. The final sample included 13,705 employees. The 12-month prevalence of chronic musculoskeletal pain was 18.6% for the whole sample, and 22.0, 21.9, 20.2 and 15.0% for employees in the work areas other, office, research/laboratory and production/craft, respectively. Regression analyses showed that the prevalence was 24.1% (p < 0.001) lower for employees in production/craft and 11.2% (p < 0.05) lower for employees in research/laboratory compared to office employees in the fully adjusted model. Conclusions. The high prevalence of chronic musculoskeletal pain underscores the importance of both the prevention and management of chronic musculoskeletal pain. Thereby, workplace-specific needs-based offerings could play an important role.

Pain revolution in the public health system: Active coping strategies for chronic pain unit

BACKGROUND

Chronic pain represents a global health challenge demanding a transition from traditional biomedical to patient-centered biopsychosocial models. This masterclass explores active coping strategies for effective chronic pain management within healthcare systems. It describes the Unit of Active Coping Strategies for Chronic Pain (UAAD - Unidad de Afrontamiento Activo para el Dolor) in Primary Care in Valladolid, Spain, as a successful example of implementing a biopsychosocial care model for treating chronic pain.

OBJECTIVE

To provide tools that allow the application of active coping strategies in the treatment of patients with chronic pain and how to implement the UAAD units in other healthcare systems.

METHODS

This masterclass describes the UAAD's innovative approach, starting with its comprehensive and personalized methodology. This includes a referral system, a thorough assessment encompassing biological, psychological, and social factors, and a functional categorization system. These elements guide personalized treatment plans delivered through group and individual programs grounded in therapeutic exercise and pain science education. Four key pillars are highlighted: clinical care, teaching, resource management, research and dissemination.

CONCLUSION

Embracing this model empowers healthcare providers to address the growing burden of chronic pain. It also enables patients to take an active role in their recovery and self-management.

Regenerative Peripheral Nerve Interface Surgery to Treat Chronic Postamputation Pain: A Prospective Study in Major Lower Limb Amputation Patients

Objective

The objective was to assess the postsurgical outcomes of regenerative peripheral nerve interface (RPNI) surgery in a prospective cohort of major lower extremity amputation patients with chronic postamputation pain.

Background

Chronic pain in lower limb amputation patients is commonly the result of neuroma formation after traumatic peripheral nerve injury. By implanting more proximal transected nerve ends into autologous free muscle grafts, RPNI surgery can treat postamputation pain by diminishing the development of neuromas. RPNI surgery in prior retrospective studies has been shown to mitigate postamputation pain.

Methods

Twenty-two lower limb amputation patients with established chronic postamputation pain were recruited from 2 studies in this prospective study. All patients underwent RPNI surgery to treat identified symptomatic neuromas within the residual limb. Patient-reported outcome instruments were administered preoperatively and postoperatively at 1 week, 4 months, and 12 months to examine residual limb pain (McGill Pain Questionnaire, PROMIS Pain Intensity, and PROMIS Pain Interference), phantom limb pain (modified PROMIS Pain Intensity and Phantom Limb sensation questionnaire), psychosocial status (PHQ-9, GAD-7, and PCS), and functional (OPUS) outcomes.

Results

RPNI surgery significantly improved residual limb pain. While phantom limb sensation improved significantly, phantom limb pain demonstrated a modest decrease. Psychosocial outcomes also improved significantly after RPNI surgery. Prosthetic use slightly increased, and patients did not experience loss of function.

Conclusions

RPNI surgery leverages the processes of reinnervation to successfully treat residual limb pain and improve psychosocial outcomes in patients with chronic postamputation pain. Phantom limb pain may be more difficult to treat in chronic pain patients who have central sensitization at the time of surgery.

Exploring the associations between the presence, characteristics, and biopsychosocial covariates of pain and lifetime depression in adolescents: A cross-sectional ABCD study analysis

INTRODUCTION

Depression and pain co-occur, even during adolescence. However, there is limited knowledge on the association between pain and lifetime depression, and which biopsychosocial measures are associated with this co-occurrence.

METHODS

Cross-sectional analysis of the Adolescent Brain and Cognitive Development (ABCD) two-year follow-up. We explored associations between the presence and characteristics of past month pain (intensity, duration, activity limitations, and number of pain sites) and lifetime depression using logistic regression. We explored associations of brain structure, physical, behavioural, emotional, social, and cognitive measures with lifetime depression and past month pain compared to having had one or neither condition using multinomial logistic regression.

RESULTS

A total of 5211 adolescents (mean age = 12.0 years) who had: (1) no lifetime mental ill-health and no pain (n = 3327); (2) pain only (n = 1407); (3) lifetime depressive disorder but no pain (n = 272); and (4) lifetime depressive disorder and pain (n = 205) were included. Pain presence was associated with lifetime depression (OR[95%CI]: 1.76 [1.45, 2.13], p < 0.001). Pain-related activity limitations (1.13 [1.06, 1.21], p < 0.001) and the number of pain sites (1.06 [1.02, 1.09], p < 0.001) were associated with lifetime depression. Various behavioural, emotional, social, and cognitive, but not brain structure or physical measures, were associated with lifetime depression and past month pain.

LIMITATIONS

Longitudinal analyses should validate prognostic markers for predicting co-occurring depression and pain.

CONCLUSIONS

Results support an association between the presence and characteristics of pain and lifetime depression during adolescence and could indicate the need for more integrated recognition and clinical care of youth experiencing both depression and pain.