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

Factor Structure of the Brief Pain Inventory-Short Form in African American Older Adults With Osteoarthritis

PURPOSE

To evaluate the factor structure of the Brief Pain Inventory-Short Form (BPI-SF) and measurement invariance across two age groups for African American (AA) older adults with osteoarthritis (OA).

METHOD

Participants were AA older adults aged 50 to 94 years with self-reported OA and chronic pain (N = 110). Cross-sectional data from the BPI-SF were obtained from all participants, and confirmatory factor analysis (CFA) was used to evaluate the factor structure. Measurement invariance across young-old (aged 50 to 69 years) and old-old (aged 70 to 94 years) participants was examined at configural, full metric, and full scalar levels.

RESULTS

CFA revealed that a three-factor model (i.e., pain intensity, activity interference, and affective interference) demonstrated the best fit (χ2/df = 1.595, comparative fit index [CFI] = 0.949, root-mean-square error of approximation = 0.074). The change of CFI between configural and metric invariance was below the cutoff point of 0.01, supporting full metric (i.e., factor loadings) invariance across the two age groups. However, full scalar (i.e., item intercepts) invariance was not demonstrated.

CONCLUSION

Results support a three-factor structure of the BPI-SF, which is consistent across two age groups for AA older adults with OA. This study provides evidence that the BPI-SF can reliably measure pain intensity and two distinct dimensions of pain interference in this population. [Journal of Gerontological Nursing, 51(2), 13-22.].

Pain management and social functioning limitations among adults with chronic pain by diabetes status: National Health Interview Survey, United States, 2019-2020

AIMS

This study aims to describe pain management technique usage and social functioning limitations among adults with chronic pain by diabetes status.

METHODS

The 2019 and 2020 National Health Interview Survey data were pooled to complete this analysis. Use of the following techniques in the past 3 months were measured: 1) prescription opioids; 2) physical, rehabilitative, or occupational therapy; 3) talk therapies; 4) chiropractic care; 5) yoga, Tai Chi, or Qi Gong; 6) massage; and 7) relaxation techniques. The social functioning limitations assessed were: 1) doing errands alone; 2) participating in social activities; and 3) work limitations. Weighted prevalence and 95 % confidence intervals (CIs) were estimated for each outcome by diabetes status. Logistic regression was used to estimate age- and sex-adjusted odds ratios (aORs) to assess differences by diabetes status.

RESULTS

Adults with diabetes and chronic pain were more likely to use prescription opioids (aOR: 1.4; 95 % CI: 1.2, 1.6) but less likely to use various nonpharmacological techniques than those without diabetes. Additionally, adults with diabetes and chronic pain were more likely to report each social functioning limitation than those without diabetes.

CONCLUSIONS

Results suggest adults with diabetes and chronic pain may be missing beneficial opportunities to manage pain.

Antinociceptive and antineuropathic effects of Trifolium resupinatum L. on formalin-induced nociception and cervical spinal cord hemi-contusion: Underlying Mechanisms

ETHNOPHARMACOLOGICAL RELEVANCE

Trifolium resupinatum L. (Fabaceae), known as Persian clover, ethnomedicinally used in Persian folk medicine to treat peritoneal inflammation, rheumatism, and back pain.

AIM OF THE STUDY

To investigate the antineuropathic and antinociceptive activities of Trifolium resupinatum leaves essential oil (TREO) in male Wistar rats, as well as to explore the potential mechanisms of action.

MATERIALS AND METHODS

The antinociceptive activity of TREO and its main constituents, quercetin (Qc) was assessed using the formalin-induced paw licking test. Moreover, the potential mechanisms of antinociception were evaluated through various competitive and non-competitive antagonisms. Additionally, the antineuropathic potential was investigated using the cervical spinal cord hemi-contusion (CCS) model, and the role of phosphorylated Stat-3 was analyzed using Western blotting.

RESULTS

TREO exerted significant antinociceptive activity (P < 0.01) in both phases of the formalin-induced test; however, its effects were more pronounced in the second phase. Modulators of the NO-cGMP-K+ channel pathway significantly reversed the antinociceptive activity of TREO (P < 0.05). Additionally, antagonists of TRPV1 and TRPV2, as well as CB1 and GABAA receptors, significantly reversed the antinociceptive effects of TREO (P < 0.05). In another study, both TREO and Qc significantly attenuated hyperalgesia and mechanical allodynia (P < 0.01) when evaluated using the CCS-induced nociception model. Notably, TREO also reduced the expression levels of interleukin-1 beta, interleukin-2, and tumor necrosis factor alpha in CCS-induced rats (P < 0.05).

CONCLUSION

TREO and Qc exhibit both antinociceptive and anti-neuropathic activities. The antinociceptive effects are partially mediated through the NO-cGMP-K+ channel pathways, along with the activation of TRPV, GABA, and cannabinoid receptors. Furthermore, the anti-neuropathic activity of TREO may be partially regulated through the inhibition of cytokines.

The impact of biofeedback in enhancing chronic pain rehabilitation: A systematic review of mechanisms and outcomes

Background and objectives

Chronic pain (CP), affecting approximately 20 % of adults globally, imposes a profound burden on individuals and healthcare systems. This condition, characterized by persistent pain, muscle stiffness, and emotional distress, often results in a complex interplay of physical and psychological factors that exacerbate symptoms and hinder recovery. Biofeedback (BFB), a non-invasive intervention, offers a promising rehabilitation strategy by enabling individuals to monitor and self-regulate physiological responses, such as muscle tension, heart rate, and skin temperature. Through this process, BFB disrupts the vicious cycle of pain and stress, fostering relaxation, reducing muscle strain, and alleviating emotional distress. This systematic review aimed to examine the mechanisms underlying BFB's therapeutic effects in CP rehabilitation, specifically its ability to enhance self-regulation and promote relaxation to improve pain control. Furthermore, it aimed to evaluate the impact of BFB on key outcomes, including pain severity, functional capabilities, and quality of life, with the goal of guiding its integration into contemporary rehabilitation practices.

Materials and Methods

Following PRISMA guidelines, a systematic search was conducted in PubMed, Web of Science, and Embase (2014-2024) to identify studies on BFB for CP. Inclusion criteria included original research involving BFB as a primary or secondary intervention for CP, with outcomes related to pain management and rehabilitation. This review is registered on Open OSF (X5HPB).

Results

BFB has shown consistent efficacy as a complementary therapy in CP management, offering significant reductions in pain intensity and enhancements in quality of life across diverse CP conditions. Mechanistically, BFB facilitates improved self-regulation by training patients to modulate physiological responses, such as muscle tension and heart rate variability, leading to better pain control and stress reduction.

Conclusions

BFB shows significant promise as a supplementary treatment for different CP disorders. The evidence that was examined shows that it is effective in improving how pain is perceived, increasing functional results, and boosting overall quality of life among a variety of patient groups.

Effectiveness of a pain science education programme in middle school students: a randomised controlled trial

Introduction

Chronic pain in childhood is a prevalent issue affecting approximately 20% of young people aged 8-16 years. This condition negatively impacts their quality of life, as well as their physical, psychological, and social functioning. In recent years, Pain Science Education has emerged as a promising strategy to enhance the conceptualization of pain and mitigate maladaptive pain-related behaviours in children and teenagers. The primary aim of this study is to assess the effectiveness of the Pain Science Education programme called "Learning Pain" in improving the conceptualization of pain amongst 11-13-year-old children enrolled in their first year of middle school.

Materials and methods

A randomised controlled trial with single-blind parallel groups was conducted. Five participating institutes were randomly assigned to either the experimental group, which received the Pain Science Education intervention through the "Learning Pain" programme consisting of two sessions spaced 1 month apart, or the control group, which underwent only study assessments. Both groups underwent initial assessment and follow-up evaluations at 1 month (short term), 7 months (medium-term), and 13 months (long-term). The main outcome measure was the conceptualization of pain, assessed using the Conceptualization of Pain Questionnaire (COPAQ).

Results

The "Learning Pain" programme, a specific Pain Science Education intervention, demonstrated effectiveness in improving the conceptualization of pain at 1, 7, and 13 months follow-up assessments.

Discussion

The "Learning Pain" programme, a specific Pain Science Education intervention, enhances the conceptualization of pain in adolescents aged 11-13 years over short, medium, and long-term periods.

Social prescribing for adults with chronic pain in the U.K.: a rapid review

Introduction

Social prescribing links patients to community groups and services to meet health needs; however, it is uncertain what the benefits and impacts of social prescribing are for people with chronic pain. The National Institute for Health and Care Excellence (NICE) undertook a systematic review to investigate the clinical and cost effectiveness of social interventions aimed at improving the quality of life of people with chronic pain; no relevant clinical studies comparing social interventions with standard care for chronic pain were found, though the inclusion criteria for studies was narrow.

Objectives

To undertake a rapid review of all types of research and policy on social prescribing for adults with chronic pain in the U.K. (i) to describe the characteristics of relevant research and (ii) to synthesise data on impact.

Methods

A two-stage rapid review was planned. Stage (i) scoped and categorised knowledge from a comprehensive representation of the literature. In stage (ii), we undertook a descriptive synthesis of quantitative data along with a thematic analysis of qualitative data identified by stage (i).

Results

Of 40 full-text records assessed for inclusion, three met the inclusion criteria from academic databases. An additional five records were found in grey literature. Six records reported quantitative findings suggesting that social prescribing reduced pain severity and discomfort, pain medication and clinical appointments; and improved quality of life and ability to manage health. Five records captured qualitative data from interviews, case studies and anecdotal quotes that suggested positive impact on health and wellbeing; and increased self-efficacy in social prescribers undertaking training on pain.

Conclusions

There is tentative evidence that social prescribing improves health and wellbeing outcomes in adults with chronic pain and that there is a need to upskill social prescribers in contemporary pain science education. Research on the routes to referral, outcomes and impacts is needed.

Perspective

Social prescribing is valued and may be of benefit for people with chronic pain. There is a need to further develop and evaluate social prescribing services for people with chronic pain to enhance holistic patient centered care.

Exploring Physician and Patient Perspectives on Expectations and Role Models Towards Chronic Pain Treatment in General Practice: A Qualitative Cross-Sectional Study

Background and Objective: Approximately 7.4% of the German population matched the criteria of impeding, chronic non-cancer-related pain in 2014. Guidelines emphasize the importance of a holistic treatment approach. The project RELIEF aims to develop and evaluate a multifaceted case-management intervention to foster the holistic management of chronic pain in general practice. To inform intervention development, this study explored expectations and perceived role models of general practitioners (GP) and patients regarding chronic non-cancer-related pain management in general practice with a focus on patient expectations of GPs and themselves, as well as GP expectations of patients and their anticipation of patient's expectations. Methods: Data were collected via semi-structured guide-based interviews with general practitioners and patients. Pseudonymized verbatim transcripts were analyzed using an inductive-deductive approach with a structuring qualitative content analysis. The Theoretical Domains Framework served as an analytical framework to explore behavioral aspects associated with expectations and role perceptions. Results:n = 25 interviews were analyzed (GP: n = 10, patient: n = 15). Findings indicate that patients considered themselves as the main actor in the therapy process yet expected guidance and care coordination from their GP. The essential role GPs play in pain management was emphasized. Role models indicated by GPs and some patients represent a care ideal, which was also reflected in discussed expectations. GPs anticipated that patients would place high relevance on pharmacological options. Patients highlighted their preference of non-pharmacological and alternative treatment options. Conclusions: Our findings demonstrate the importance of holistic, individually tailored chronic pain management in general practice. Systematic, multifaceted case management, as planned in the RELIEF project, may contribute to high-quality primary care for affected individuals.

Metabolite-Sensing Receptors: Emerging Targets for Modulating Chronic Pain Pathways

Chronic pain is a debilitating condition affecting millions worldwide, often resulting from complex interactions between the nervous and immune systems. Recent advances highlight the critical role of metabolite-sensing G protein-coupled receptors (GPCRs) in various chronic pain types. These receptors link metabolic changes with cellular responses, influencing inflammatory and degenerative processes. Receptors such as free fatty acid receptor 1 (FFAR1/GPR40), free fatty acid receptor 4 (FFAR4/GPR120), free fatty acid receptor 2 (FFAR2/GPR43), and Takeda G protein-coupled receptor 5 (TGR5/GPR131/GPBAR1) are key modulators of nociceptive signaling. GPR40, activated by long-chain fatty acids, exhibits strong anti-inflammatory effects by reducing cytokine expression. Butyrate-activated GPR43 inhibits inflammatory mediators like nitric oxide synthase-2 and cyclooxygenase-2, mitigating inflammation. TGR5, activated by bile acids, regulates inflammation and cellular senescence through pathways like NF-κB and p38. These receptors are promising therapeutic targets in chronic pain, addressing the metabolic and inflammatory factors underlying nociceptive sensitization and tissue degeneration. This review explores the molecular mechanisms of metabolite-sensing receptors in chronic pain, their therapeutic potential, and challenges in clinical application. By uncovering these mechanisms, metabolite-sensing receptors could lead to safer, more effective pain management strategies.

Perceptual Disturbances and Disorders in the ICD-11: An Overview and a Proposal for Systematic Classification

The International Classification of Diseases (ICD) has been developed and edited by the World Health Organisation and represents the global standard for recording health information and causes of death. The ICD-11 is the eleventh revision and came into effect on 1 January 2022. Perceptual disturbances refer to abnormalities in the way sensory information is interpreted by the brain, leading to distortions in the perception of reality. These can manifest as distorted perceptions or as phantom perceptions and can occur in all sensory modalities as visual, auditory, olfactory, gustatory tactile, vestibular, proprioceptory or interoceptory disturbances. There are similar brain mechanisms involved in the generation of these analogous perceptual disturbances and disorders, and they are treated with similar approaches. Perceptual disturbances are highly prevalent, with large variations across the different sensory modalities. They can be associated with significant suffering and cause a high socioeconomic burden. Perceptual disturbances can be symptoms of another disease or disease entities on their own. In the context of pain, this is reflected by the distinction between secondary pain (pain as a symptom of another underlying condition) and primary pain (a disease in its own right, rather than being a symptom of another underlying condition) in the ICD-11. Such a clear distinction is not found in an entirely consistent way across the various sensory modalities. By using the example of auditory phantom perceptions, we propose a framework for the classification of sensory disorders in alignment with the classification of pain in the ICD-11. The descriptions of the sensory disturbances should include (1) a causal aspect (primary versus secondary), (2) a temporal aspect (acute vs. chronic and persistent vs. intermittent), (3) a cognitive, emotional and autonomic interpretation aspect (=suffering) and (4) a social aspect (=disability). If the latter two aspects are present, we propose that the sensory disturbance is called a sensory disorder.

Gamified Web-Delivered Attentional Bias Modification Training for Adults With Chronic Pain: Randomized, Double-Blind, Placebo-Controlled Trial

BACKGROUND

Attentional bias to pain-related information has been implicated in pain chronicity. To date, research investigating attentional bias modification training (ABMT) procedures in people with chronic pain has found variable success, perhaps because training paradigms are typically repetitive and monotonous, which could negatively affect engagement and adherence. Increasing engagement through the gamification (ie, the use of game elements) of ABMT may provide the opportunity to overcome some of these barriers. However, ABMT studies applied to the chronic pain field have not yet incorporated gamification elements.

OBJECTIVE

This study aimed to investigate the effects of a gamified web-delivered ABMT intervention in a sample of adults with chronic pain via a randomized, double-blind, placebo-controlled trial.

METHODS

A final sample of 129 adults with chronic musculoskeletal pain, recruited from clinical (hospital outpatient waiting list) and nonclinical (wider community) settings, were included in this randomized, double-blind, placebo-controlled, 3-arm trial. Participants were randomly assigned to complete 6 web-based sessions of nongamified standard ABMT (n=43), gamified ABMT (n=41), or a control condition (nongamified sham ABMT; n=45) over a period of 3 weeks. Active ABMT conditions trained attention away from pain-related words. The gamified task included a combination of 5 game elements. Participant outcomes were assessed before training, during training, immediately after training, and at 1-month follow-up. Primary outcomes included self-reported and behavioral engagement, pain intensity, and pain interference. Secondary outcomes included anxiety, depression, cognitive biases, and perceived improvement.

RESULTS

Results of the linear mixed model analyses suggest that across all conditions, there was an overall small to medium decline in self-reported task-related engagement between sessions 1 and 2 (P<.001; Cohen d=0.257; 95% CI 0.13-0.39), sessions 1 and 3 (P<.001; Cohen d=0.368; 95% CI 0.23-0.50), sessions 1 and 4 (P<.001; Cohen d=0.473; 95% CI 0.34-0.61), sessions 1 and 5 (P<.001; Cohen d=0.488; 95% CI 0.35-0.63), and sessions 1 and 6 (P<.001; Cohen d=0.596; 95% CI 0.46-0.73). There was also an overall small decrease in depressive symptoms from baseline to posttraining assessment (P=.007; Cohen d=0.180; 95% CI 0.05-0.31) and in pain intensity (P=.008; Cohen d=0.180; 95% CI 0.05-0.31) and pain interference (P<.001; Cohen d=0.237; 95% CI 0.10-0.37) from baseline to follow-up assessment. However, no differential effects were observed over time between the 3 conditions on measures of engagement, pain intensity, pain interference, attentional bias, anxiety, depression, interpretation bias, or perceived improvement (all P values>.05).

CONCLUSIONS

These findings suggest that gamification, in this context, was not effective at enhancing engagement, and they do not support the widespread clinical use of web-delivered ABMT in treating individuals with chronic musculoskeletal pain. The implications of these findings are discussed, and future directions for research are suggested.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ANZCTR) ACTRN12620000803998; https://anzctr.org.au/ACTRN12620000803998.aspx.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.2196/32359.

Rationale and design for the thoracic Paravertebral Adjunctive Dexamethasone Palmitate Reducing chronic pain After cardiac surgery (PANDORA) trial: a parallel-group, double-blinded, randomised controlled, single-centre study

INTRODUCTION

Minimally invasive cardiac surgery (MICS) is important for enhanced recovery in cardiac surgery. However, the incidence of chronic postsurgical pain (CPSP) is high and is associated with worsened quality of recovery and life, as well as raised short-term or long-term mortality. The mechanism is not clear, and there is still a lack of safe and effective preventive measures.

METHODS AND ANALYSIS

The Paravertebral Adjunctive Dexamethasone Palmitate Reducing chronic pain After cardiac surgery (PANDORA) trial is a parallel-group, double-blinded, randomised controlled, single-centre study recruiting 902 participants undergoing MICS. Participants will be randomised in a 1:1 ratio to dexamethasone palmitate (D-PAL) emulsion group and dexamethasone (DSP) group. To investigate the effect of a single bolus perineural administration of D-PAL as an adjuvant treatment to a standard thoracic paravertebral block (TPVB) with ropivacaine decreases the incidence of CPSP in adult patients as compared with single bolus perineural administration of DSP combined with ropivacaine in TPVB. The primary endpoint is the incidence of chronic postoperative pain at 3 months following surgery defined as per the updated International Classification of Diseases. CPSP is defined as a new development of pain or increase in the intensity of pain at the surgical area or projected onto the innervation area of a nerve in this area after a surgical procedure that persists for at least 3 months. The nature and intensity of pain will be evaluated with a Brief Pain Inventory Short Form (BPI-SF) questionnaire.

ETHICS AND DISSEMINATION

The trial was approved by the Ethics Committee of Xijing Hospital, the First Affiliated Hospital of Air Force Military Medical University (KY20232194-C-1). Results will be submitted for publication in peer-reviewed journals and presented at academic meetings.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov, NCT05920967.

Exploring the therapeutic potential of TRPC channels in chronic pain: An investigation into their mechanisms, functions, and prospects

Transient Receptor Potential Canonical (TRPC) channels have received more attention in recent years for their role of in the pathophysiology of chronic pain. These non-selective cation channels, which are predominantly present on cell membranes, play a pivotal role in regulating both physiological and pathological processes. Research advances have shown the critical role of TRPC channels in a variety of chronic pain, including neuropathic, inflammatory, and visceral pain. Activation of TRPC channels increases neuronal excitability, amplifying and prolonging pain signals. Moreover, these channels collaborate with other ion channels and receptors to form complexes that augment the transmission and perception of pain. As research advances, our understanding of TRPC channels' regulation mechanisms and signaling pathways improves. An expanding variety of TRPC modulators has been identified as promising therapeutic agents for chronic pain, opening up novel treatment options. Nevertheless, the diversity and complexity of TRPC channels present challenges in drug development, highlighting the importance of full understanding of their unique properties and activities. This review aims to provide a thorough evaluation of recent breakthrough in TRPC channels research related to chronic pain, with a focus on their mechanisms, functions, and prospective therapeutic application. By integrating existing research findings, we seek to bring new viewpoints and approaches for chronic pain management.

Physicians' and patients' perceived risks of chronic pain medication and co-medications in Quebec, Canada: a cross-sectional study

BACKGROUND

The risks associated with medications and co-medications for chronic pain (CP) can influence a physician's choice of drugs and dosages, as well as a patient's adherence to the medication. High-quality care requires patients to participate in medication decisions. This study aimed to compare perceived risks of medications and co-medications between physicians and persons living with CP.

METHODS

This cross-sectional survey conducted in Quebec, Canada, included 83 physicians (snowball sampling) and 141 persons living with CP (convenience sampling). Perceived risks of adverse drug reaction of pain medications and co-medications were assessed using 0-10 numerical scales (0 = no risk, 10 = very high risk). An arbitrary cutoff point of 2-points was used to ease the interpretation of our data. Physicians scored the 36 medication subclasses of the Medication Quantification Scale 4.0 (MQS 4.0) through an online survey, while CP patients scored the medication subclasses they had taken in the last three months through telephone interviews.

RESULTS

Persons living with CP consistently perceived lower risks of adverse drug reaction compared to physicians. For eight subclasses, the difference in the mean perceived risk score was > 2 points and statistically significant (p < 0.05): non-specific oral NSAIDs, acetaminophen in combination with an opioid, short-acting opioids, long-acting opioids, tricyclic antidepressants, antipsychotics, benzodiazepines, and medical cannabis.

CONCLUSIONS

Divergent risk perceptions between physicians and patients underscore the necessity of facilitating a more extensive discussion on medications and co-medications risks to empower patients to make informed decisions and participate in shared decision-making regarding their treatments.

Presurgical anxiety and acute postsurgical pain predict worse chronic pain profiles after total knee/hip arthroplasty

INTRODUCTION

Total joint arthroplasties generally achieve good outcomes, but chronic pain and disability are a significant burden after these interventions. Acknowledging relevant risk factors can inform preventive strategies. This study aimed to identify chronic pain profiles 6 months after arthroplasty using the ICD-11 (International Classification of Diseases) classification and to find pre and postsurgical predictors of these profiles.

MATERIALS AND METHODS

Patients undergoing total knee/hip arthroplasty (n = 209, female = 54.5%) were assessed before surgery, 48 h and 6 months postsurgery for sociodemographic, pain-related, disability and psychological characteristics. K-means-constrained cluster analysis identified chronic pain profiles based on 6-month pain intensity, pain interference and disability. Chi-square tests or one-way ANOVA explored between-cluster differences. Multinomial regression identified predictors of cluster membership. Separate models analyzed presurgical (model 1), postsurgical (model 2) and a combination of previously significant pre and postsurgical (model 3) variables.

RESULTS

A three-cluster solution was selected, translating increasingly worse chronic pain severity: cluster 1 (C1, n = 129), cluster 2 (C2, n = 60) and cluster 3 (C3, n = 20). There were presurgical differences among clusters in the presence of other painful sites (p = 0.013, ϕc = 0.20), pain interference (p = 0.038, η2 = 0.031), disability (p = 0.020, η2 = 0.037), pain catastrophizing (p = 0.019, η2 = 0.060), anxiety (p < 0.001, η2 = 0.087), depression (p = 0.017; η2 = 0.039), self-efficacy (p = 0.018, η2 = 0.038) and satisfaction with life (p = 0.034, η2 = 0.032), postsurgical pain frequency (p = 0.003, ϕc = 0.243) and intensity (p < 0.001, η2 = 0.101). In model 1, disability predicted C2 (OR = 1.040) and anxiety predicted C3 (OR = 1.154) membership. In model 2, pain intensity predicted C3 (OR = 1.690) membership. In model 3, presurgical anxiety predicted C3 (OR = 1.181) and postsurgical pain intensity predicted C2 (OR = 1.234) and C3 (OR = 1.679) membership.

CONCLUSIONS

Most patients had low chronic pain severity at 6 months, but a relevant percentage exhibited poor outcomes. Membership to different outcome profiles was predicted by presurgical anxiety and acute postsurgical pain. These seem promising targets to prevent pain chronification that should be optimized for better surgical outcomes.

Stress, perceived competence and guilt as predictors of depression in parents with chronic pain

Introduction

Suffering from chronic pain (CP) and coping with parenthood can be challenging for parental mental health. Pain can hinder the ability to deal with demands related to parenthood, which can negatively affect their psychological well-being because of unmet caregiving expectations.

Methods

Considering the limited amount of research regarding the mental health of parents with CP, the study's main aim was to test a predictive model based on previous scientific literature, using structural equation analysis, in which parental competence and parental guilt partially mediate the relationship between parental stress and depression. To examine the moderating role of CP, the model was tested on a group of parents with CP and a control group of parents without CP. The study included 380 parents from all over Spain, of which 200 formed the group with CP and 180 participants formed the control group. A cross-sectional design was used to collect data through self-report measures.

Results

Higher levels of stress, guilt, and depression were observed in parents with CP. Based on the results, both groups of parents showed a good fit with the predictive model; parental stress was a good predictor of symptoms of depression both in parents with and without CP, parental competence mediated the relationship between parental stress and depression, being the relationship between competence and depression partially mediated by parental guilt.

Discussion

This study is the first to quantitatively examine parental competence and guilt in parents with CP, and to analyze their role as mediators between parental stress and depression in both CP and healthy parents. The results confirm previous qualitative findings and extend them to parents with CP, showing that the tested model aligns with the main theories on stress, self-efficacy, and depression, as well as existing literature on CP. These results suggest the relevance of addressing parental stress levels for reducing and preventing depressive symptoms in parents with CP and the importance of working on guilt reduction and enhancing competence in order to improve the emotional well-being of parents. The need to take into account the mental health of parents with CP to improve their quality of life is discussed.

Chronic overlapping pain conditions and nociplastic pain

Chronic overlapping pain conditions (COPCs) are a subset of chronic pain conditions commonly comorbid with one another and more prevalent in women and individuals assigned female at birth (AFAB). Pain experience in these conditions may better fit with a new mechanistic pain descriptor, nociplastic pain, and nociplastic pain may represent a shared underlying factor among COPCs. We applied GenomicSEM common-factor genome-wide association study (GWAS) and multivariate transcriptome-wide association (TWAS) analyses to existing GWAS output for six COPCs in order to find genetic variation associated with nociplastic pain, followed by genetic correlation (linkage disequilibrium score regression), gene set, and tissue enrichment analyses. We found 24 independent single nucleotide polymorphisms (SNPs), and 127 unique genes significantly associated with nociplastic pain, and showed nociplastic pain to be a polygenic trait with significant SNP heritability. We found significant genetic overlap between multisite chronic pain and nociplastic pain, and to a smaller extent with rheumatoid arthritis and a neuropathic pain phenotype. Tissue enrichment analyses highlighted cardiac and thyroid tissue, and gene set enrichment analyses emphasized potential shared mechanisms in cognitive, personality, and metabolic traits and nociplastic pain along with distinct pathology in migraine and headache. We used a well-powered network approach to investigate nociplastic pain using existing COPC GWAS output, and show nociplastic pain to be a complex, heritable trait, in addition to contributing to understanding of potential mechanisms in development of nociplastic pain.

Utilization of telemedicine in conjunction with wearable devices for patients with chronic musculoskeletal pain: a randomized controlled clinical trial

The present randomized controlled trial aimed to investigate the effects of home-based telemedicine with wearable devices and usual care on pain-related outcomes in patients with chronic musculoskeletal pain, compared to usual care alone. The patients with chronic musculoskeletal pain were randomly allocated to the usual care group or the telemedicine group, which participated in telemedicine with wearable devices, the objective data from which were recorded, in conjunction with usual care for six months. The primary outcome measure was the Numeric Rating Scale (NRS) for pain. The secondary outcome measures were the Pain Catastrophizing Scale (PCS), Hospital Anxiety and Depression Scale (HADS), Pain Disability Assessment Scale (PDAS), and EuroQol-five dimensions-three level (EQ-5D-3L). Seventy-one participants were analyzed. At 1 and 3 months, there were no significant differences in the NRS scores between the groups; however, the telemedicine group had a significantly superior effect on all of the outcome measures at 6 months compared to the usual care group. The number of steps and distance were significantly increased at 6 months compared to baseline in the telemedicine group. Home-based telemedicine with wearable devices and usual care has a modest effect on pain-related outcomes compared to usual care in patients with chronic musculoskeletal pain.This study was registered (UMIN000052994 - 04/12/2023).

Understanding the Physiopathology of Pain Pathways for a Practical Approach of Cancer Pain Management

Pain associated with cancer is often the first symptom reported with major repercussions on patient's quality of life. Mechanical compression, release of algogenic substances by the tumor or the complications of oncologic treatment represent the major causes. Nociceptive and neuropathic pain are both induced by different mediators that give rise to a neuroinflammation creating a peripheral and central sensitization responsible of chronic pain. Understanding the pain pathway may orientate to the most appropriate treatment. Oral medication should be often reevaluated to consider multimodal analgesia including interventional pain procedures with intrathecal therapy and neuromodulation.

Does rehabilitation improve work participation in patients with chronic spinal pain after spinal surgery: a systematic review

OBJECTIVE

Patients with therapy-refractory chronic spinal pain after spinal surgery experience increased disability, resulting in substantial loss of employment and consequently lower quality of life. Despite findings that rehabilitation improves socio-economic outcomes in other chronic pain conditions, evidence for patients with chronic spinal pain after spinal surgery is limited. A systematic review was conducted to provide an overview of rehabilitation interventions and their effectiveness to improve work participation for patients with chronic spinal pain after spinal surgery.

METHODS

MEDLINE (via PubMed), Scopus, Embase, and Web of Science, were systematically searched. Risk of bias was assessed using the modified Downs and Black checklist and GRADE was used to assess certainty of evidence. The review protocol was prospectively registered on PROSPERO (CRD42022346091).

RESULTS

The search yielded 1,289 publications. Full-text screening of 48 articles resulted in the inclusion of 6 publications. The included interventions comprised multiple treatment components, consisting of back school, self-care, functional restoration, multidisciplinary rehabilitation, physiotherapy, and digital care programmes to improve work participation.

CONCLUSION

Rehabilitation to improve return to work for patients with chronic spinal pain after spinal surgery was supported only by low-certainty evidence. Rehabilitation therapies that are personalized and that integrate the patient's work seem most suitable.

Pain and the perception of space in fibromyalgia

The Economy of action hypothesis postulates that bodily states rescale the perception of the individual's environment's spatial layout. The estimation of distances and slopes in navigation space (i.e. the space reachable by locomotion) is influenced by sensations relating to body condition and the metabolic cost of the actions. The results of the studies investigating the impact of pain on distance estimation remain inconclusive. 28 women suffering from chronic pain and fibromyalgia (FM), and 24 healthy women (HC) were assessed for musculoskeletal, neuropathic, and visceral pain by means of the Widespread Pain Index, the Symptom Severity Scale and an ad-hoc devised questionnaire for pain (the Verona Pain Questionnaire). In a VR-mediated task, they observed a 3D scenario and estimated the distance of a flag positioned at different distances (1, 2, 3, 4 or 5 m) on virtual ramps with either a 4% or 24% inclination in two different conditions: sitting and standing. Overestimation of distances in the steeper ramp condition was expected, if participants executed the task by internally simulating the movement. The results showed a dissociation between the effects of musculoskeletal and visceral-neuropathic pain on distance estimations. While, according to the Economy of Action hypothesis, the HCs estimated the distances as being farther away when the ramp was more inclined (i.e. with a 24% inclination), there was no effect related to the different ramp inclinations in the FM group. Furthermore, visceral and neuropathic pain were found to affect the performance of the FM group. These results suggest that chronic and widespread pain conditions, that typically characterize fibromyalgia, can affect space representations. In line with the Economy of Action hypothesis, bodily based estimation of distances is compromised in these patients.

Nociplastic pain: controversy of the concept

Classically, pain can be of a nociceptive or neuropathic nature, which refers to non-neural or neural tissue lesions, respectively. Chronic pain in conditions such as migraine, fibromyalgia, and complex regional pain syndrome (CRPS), is thought to perpetuate without a noxious input. Pain in such patients can be assigned neither to the nociceptive nor neuropathic category. Therefore, a third pain descriptor, named "nociplastic pain", has been adopted by the International Association for the Study of Pain. The current controversy-focused narrative review updates littledebated aspects of the new pain concept. The most disputable feature of nociplastic pain is its autonomous persistence, i.e., existence without causative tissue damage, presumably because of a malfunction of pain pathways and processing. This contradicts the fact that nociplastic pain is accompanied by persistent central sensitization that has been shown to require a continuing noxious input, e.g ., nerve injury. Even if sensitization occurs without a lesion, e.g ., in psychogenic and emotional pain, peripheral stimulus is necessary to produce pain. A logical weakness of the concept is that the word "plastic" in biology refers to adaptation rather than to maladaptation. The pathophysiologic mechanism of nociplastic pain may, in fact, be associated with background conditions that elude diagnosis because of the limitations of current diagnostic means. Misapplication of the nociplastic pain category may weaken diagnostic alertness toward occult causes of pain. Possible diagnostic errors could be avoided by understanding that nociplastic pain is a mechanism of pain rather than a diagnosis. Clinical use of this pain descriptor deserves a wider critical discussion.

Exploring the complexities of chronic pain: The ICEPAIN study on prevalence, lifestyle factors, and quality of life in a general population

OBJECTIVES

The ICEPAIN study is a longitudinal research project focused on building an extensive database on health-related quality of life (HRQoL), lifestyle, and pain among the general population in Iceland. The project started with a cross-sectional data collection and will be followed by similar data collection after 5 and 10 years from participants who have agreed to be contacted again. In this article, descriptive data on the prevalence and nature of chronic pain in the Icelandic general population will be presented in relation to sociodemographic factors, lifestyle, adverse life experiences, and HRQoL.

METHODS

Data were collected through a web-based platform using a national panel representing a randomised population sample of 12,400 individuals aged 18-80 years from the National Population Register of Iceland. The instruments consisted of questionnaires on pain, lifestyle factors, adverse life experiences, and HRQoL. The sample was stratified according to age, gender, and residence.

RESULTS

The response rate was 45% (N = 5,557), and most participants (81%) agreed to be contacted again for later data collection. The mean age of the respondents was 54.8 years (SD = 13.7). Half of the participants (50.3%) had experienced some pain the previous week, and 40% had chronic pain (≥3 months). The prevalence of chronic pain was inversely related to educational level and satisfaction with household income and positively associated with body mass index. A significant correlation was found between chronic pain prevalence and several lifestyle variables, such as physical exercises, smoking habits, sleep, and adverse life experiences. Chronic pain had a significant negative impact on both physical and mental components of HRQoL.

CONCLUSION

These results indicate a complex relationship between chronic pain, lifestyle, and adverse life experiences. The longitudinal design will provide further information on the long-term development among these variables.

Psychometric examination of the Multidimensional Psychological Flexibility Inventory Short Form (MPFI-24) and the Psy-Flex Spanish versions in individuals with chronic pain

BACKGROUND

Acceptance and Commitment Therapy (ACT) has been found to be beneficial for individuals dealing with chronic pain. The theoretical mechanisms of change proposed by ACT are based on the Hexaflex model. To comprehensively reflect this model, the Multidimensional Psychological Flexibility Inventory (MPFI) and Psy-Flex have been developed. The study aimed to adapt the MPFI-24 and the Psy-Flex for Spanish-speaking populations with chronic pain and to examine their dimensionality, internal consistency, convergent validity and incremental validity.

METHODS

This cross-sectional study involved 309 Spanish-speaking adults with chronic pain who completed an online survey. The majority of the participants were women (88.3%). The ages ranged from 18 to 79 years.

RESULTS

Factor analysis showed that the Spanish version of the MPFI-24 has 12 factors, consisting of six flexibility and six inflexibility factors, similar to the original version, but lacking second-order general factors. The Psy-Flex demonstrated a single-factor structure, maintaining the general factor of psychological flexibility seen in the original version. The MPFI-24 showed good internal consistency and adequate convergent validity, with the exception of the Acceptance and Experiential Avoidance subscales. The Psy-Flex showed good internal consistency and convergent validity. Notably, both the MPFI-24 and Psy-Flex scores significantly explained additional variance in psychological distress beyond other ACT-related measures of Hexaflex processes; however, only the Psy-Flex explained pain interference.

CONCLUSIONS

The Spanish adaptations of the MPFI-24 and Psy-Flex are valid and reliable instruments for assessing the Hexaflex model processes in Spanish-speaking adults with chronic pain.

SIGNIFICANCE STATEMENT

Practitioners and researchers in chronic pain will find the Spanish versions of the MPFI-24 and the Psy-Flex here, along with recommendations for their use and scoring based on a robust psychometric rationale. It should be noted that these measures surpass the Chronic Pain Acceptance Questionnaire (CPAQ) and the Psychological Inflexibility in Pain Scale (PIPS), which are considered gold standards in chronic pain assessment.

Chronic Musculoskeletal Pain and Risk of Incident Parkinson's Disease: A 13-Year Longitudinal Study

BACKGROUND

Chronic musculoskeletal pain often co-occurs with Parkinson's disease (PD); however, whether individuals with chronic pain have a higher risk of developing PD is unclear.

OBJECTIVES

To investigate the associations between chronic pain and incident risk of three neurodegenerative parkinsonism categories including PD, multiple system atrophy (MSA), and progressive supranuclear palsy (PSP).

METHODS

This study included 355,890 participants (mean [standard deviation] age, 56.51 [8.07] years, 48.40% male) who did not have parkinsonism at baseline from a population-based cohort. Musculoskeletal pain in the hip, neck/shoulder, back, knee, or "all over the body" was assessed. Chronic pain was defined if pain lasted ≥3 months. Participants were categorized into four groups: no chronic pain, having one or two, three or four sites, and pain "all over the body." The diagnosis of PD, MSA, and PSP used self-reports, hospital records, and death registries. Multivariable-adjusted Cox regression was performed for the analyses.

RESULTS

Over a median follow-up of 13.0 years, 2044 participants developed PD, 77 participants developed MSA, and 126 participants developed PSP. In multivariable analyses, there was a dose-response relationship between number of chronic pain sites and incident risk of PD (hazard ratio, 1.15; 95% confidence interval, 1.07-1.23). Participants with one or two pain sites and three or four pain sites had an 11% and 49% increased risk of developing PD, respectively. There were no associations between chronic pain and MSA or PSP.

CONCLUSIONS

Chronic musculoskeletal pain was independently associated with PD, suggesting that chronic pain could be used to identify individuals at risk of developing PD. © 2024 International Parkinson and Movement Disorder Society.

9. Chronic knee pain

INTRODUCTION

Chronic knee pain is defined as pain that persists or recurs over 3 months. The most common is degenerative osteoarthritis (OA). This review represents a comprehensive description of the pathology, diagnosis, and treatment of OA of the knee.

METHODS

The literature on the diagnosis and treatment of chronic knee pain was retrieved and summarized. A modified Delphi approach was used to formulate recommendations on interventional treatments.

RESULTS

Patients with knee OA commonly present with insidious, chronic knee pain that gradually worsens. Pain caused by knee OA is predominantly nociceptive pain, with occasional nociplastic and infrequent neuropathic characteristics occurring in a diseased knee. A standard musculoskeletal and neurological examination is required for the diagnosis of knee OA. Although typical clinical OA findings are sufficient for diagnosis, medical imaging may be performed to improve specificity. The differential diagnosis should exclude other causes of knee pain including bone and joint disorders such as rheumatoid arthritis, spondylo- and other arthropathies, and infections. When conservative treatment fails, intra-articular injections of corticosteroids and radiofrequency (conventional and cooled) of the genicular nerves have been shown to be effective. Hyaluronic acid infiltrations are conditionally recommended. Platelet-rich plasma infiltrations, chemical ablation of genicular nerves, and neurostimulation have, at the moment, not enough evidence and can be considered in a study setting. The decision to perform joint-preserving and joint-replacement options should be made multidisciplinary.

CONCLUSIONS

When conservative measures fail to provide satisfactory pain relief, a multidisciplinary approach is recommended including psychological therapy, integrative treatments, and procedural options such as intra-articular injections, radiofrequency ablation, and surgery.

Knowledge mapping and emerging trends in cognitive impairment associated with chronic pain: A 2000-2024 bibliometric study

Chronic pain is commonly recognized as a distressing symptom or a standalone disease, with over half of those affected experiencing cognitive impairment, which significantly impacts their quality of life. Despite a recent surge in literature on cognitive impairment associated with chronic pain, a comprehensive bibliometric analysis in this field has yet to be conducted. In this study, we performed a bibliometric analysis on this topic. We retrieved English-language publications on chronic pain and cognitive impairment from 2000 to 2024 using the Web of Science Core Collection database. These publications were visually analyzed using tools such as VOSviewer, CiteSpace, and the R package "bibliometrix." We identified 1656 publications from 72 countries/regions across 722 journals on the topic of chronic pain and cognitive impairment. Publication numbers showed a steady increase, peaking in 2022. The United States led in contributions, with Harvard Medical School emerging as the most prominent institution involved. The journal Pain was the most prolific and frequently co-cited in this area. Among the authors, Stefan Duschek was the most productive, while Frederick Wolfe was the most frequently co-cited. Key research areas include investigating the bidirectional long-term effects between chronic pain and cognitive impairment and exploring the mechanisms underlying cognitive changes associated with chronic pain. In conclusion, this study highlights a global surge in research on cognitive impairment related to chronic pain. Emerging hotspots and future research trends point towards brain imaging mechanisms and neuronal circuit-mediated processes.

Within-person relationships between catastrophizing and pain intensity during a mind-body intervention to prevent persistent pain and disability after acute traumatic orthopedic injury

Interventions aimed at preventing chronic pain after acute traumatic injury have significant potential to reduce healthcare expenditures and improve quality of life for millions of individuals. Given recent development of such interventions, limited research has examined mechanisms of change using repeated measures (e.g., session-by-session assessments). This study examines within-person relationships between pain catastrophizing and intensity during and after a four-session mind-body intervention for individuals with acute traumatic orthopedic injury (N = 76, T = 445). Random intercept cross-lagged panel models were used to examine within-person autoregressive, contemporaneous, and cross-lagged effects between pain catastrophizing and pain intensity, after accounting for stable between-person differences. Our primary hypothesis that improvements in catastrophizing would be associated with subsequent reductions in pain intensity was partially supported by a significant within-person cross-lagged effect between catastrophizing at post-test and pain with activity reported at three-month follow-up (β = 0.421, SE = 0.099, p < .001). Improvement in catastrophizing was also associated with same-session improvement in pain intensity midway through the intervention. Importantly, bidirectional within-person analyses allowed us to rule out the possibility that improvements in pain were responsible for subsequent improvements in catastrophizing, but not vice versa. Together, these findings suggest improvements in catastrophizing during psychosocial intervention may prevent transition from acute to chronic pain after injury. Future research with larger between-person sample sizes, more frequent within-person assessment, and comparable control group data is necessary to facilitate greater understanding of psychosocial mechanisms for preventing chronic pain after injury. PERSPECTIVE: This study examines within-person relationships between pain catastrophizing and intensity during and after a four-session mind-body intervention to prevent persistent pain after acute traumatic orthopedic injury. Improved catastrophizing at post-test was associated with reduced pain with activity at three-month follow-up. Within-person analyses enhance understanding of psychosocial mechanisms for preventing chronic pain after injury.

The Role of Alpha-7 Nicotinic Acetylcholine Receptors in Pain: Potential Therapeutic Implications

Chronic pain represents a prevalent and costly medical challenge globally. Nicotinic acetylcholine receptors (nAChRs), one type of ligand-gated ion channels found extensively in both the central and peripheral nervous systems, have emerged as promising therapeutic targets for chronic pain. Although there are currently no FDA-approved analgesics specifically targeting nAChRs, accumulating preclinical and clinical evidence suggest that selective ligands for alpha 7 (α7) nAChRs show potential for treating chronic pain, boasting a reduced incidence of side effects compared with other nicotinic receptor types. The recent structural resolution of human α7 nAChRs has confirmed their negative association with heightened pain, providing a valuable foundation for the development of targeted medications. This review presents a comprehensive overview, encompassing insights into the roles of α7 nAChRs derived from structural and functional studies, recent advancements in pharmacology, and investigations into their involvement in the pathophysiology of chronic pain. Moreover, the review addresses the variability in analgesic effects based on the type of receptor agonist and highlights the current research limitations. As such, this review offers potential therapeutic approaches for the development of innovative strategies for chronic pain management.

Impact of chronic low back pain on implicit motor imagery assessed by a new laterality judgment task

It is clear that implicit motor imagery (IMI) is impaired by chronic pain in peripheral regions (hand, feet), but unclear in axial regions (neck, shoulder, back). Previous IMI tasks displayed small-amplitude movements of axial regions, which limits person-centered IMI processes mobilization. This study aimed to assess the impact of chronic low back pain (CLBP) on IMI processes with a new task displaying large-amplitude whole-body movements mobilizing the lumbar spine. Twenty patients with CLBP and twenty age-matched controls performed a laterality judgment task on four distinct whole-body movements (trunk flexion, trunk rotation, capoeira, kickboxing). Participants viewed images from four different body viewpoints (back, left, right and front), randomly presented. Mixed ANOVAs were used to compare judgment accuracy and response times between groups and conditions. In participants with CLBP, response times were longer than in controls. The response times of participants with CLBP were also associated with DN4 scores, a self-reported questionnaire assessing neuropathic pain. We validated the use of a person-centered IMI because, for all participants, the accuracy decreased and the response times increased for images presented in the front viewpoint, i.e. when a 180° turn in IMI was required, compared to other viewpoints. The laterality judgment task proposed here confirmed that CLBP impacts IMI processes, and that the nature of pain (neuropathic or mechanical) needs to be considered because it seems to modulate IMI processes. PERSPECTIVE: A laterality judgment task with large-amplitude lumbar movements is key to show that CLBP alters processing speed of sensorimotor information originating from the painful region. This task could become an objective tool, transferable in clinical settings, for assessing the impact and the progression of CLBP on motor control processes.

Interactions of pain and opioids on conditioned place preference in rodents

RATIONALE

Opioid analgesics are the most effective medications used for the treatment of pain, however there are significant risks associated with repeated opioid use including opioid misuse and opioid use disorder development. Chronic pain affects millions of adults in the United States, and opioid misuse is often comorbid with pain conditions in individuals who are repeatedly treated with opioids. In addition to providing pain relief, opioids produce rewarding effects, but in chronic pain states, reward processing can become dysregulated. The conditioned place preference task is commonly used to measure the rewarding properties of opioids in rodents. During this task, opioid administration is paired with a distinct environment through repeated conditioning and the change in an animal's preference for the paired environment indicates whether the opioid is rewarding or not.

OBJECTIVES

Rodent pain models can be combined with conditioned place preference to examine the effects of pain on opioid reward. The existing preclinical literature on pain effects on conditioned place preference is conflicting, where pain conditions have been reported to enhance, suppress, or have no effect on opioid reward. This review will discuss several factors that may contribute to these discordant findings including conditioning session duration and number, rodent strain differences in opioid sensitivity, analgesic properties of opioids at tested doses, locomotor effects at tested doses, and diurnal variation in pain sensitivity. Future studies should consider how these factors contribute to opioid conditioned place preference in both pain and pain-free animals to have a better understanding of the interactions between pain and opioid reward.

The measurement of "high-impact chronic pain": Limitations and alternative methods

OBJECTIVE

Chronic pain is known to be an important construct in clinical practice and a particular form of chronic pain, high-impact chronic pain (HICP), has gained recent interest and attention by pain clinicians, epidemiologists, and clinical researchers. The purpose of our Topical Review is to describe the historical development of measures of HICP and to explore the psychometric properties of HICP as well as to present alternative measurement methods.

METHODS

We identified strengths and weaknesses of the psychometric characteristics of HICP measures. Limitations of existing HICP measures were discussed and summarized and alternatives to current methods were proposed.

RESULTS

HICP operational definitions show variability across studies. All definitions cannot be correct, but which ones are incorrect cannot be determined as there is no gold standard. Random measurement error and recall bias are among the other limitations of current HICP measures. Model-based definitions of HICP, the discrete (for epidemiologic applications) and continuous (for clinical applications) latent variable models are discussed as likely superior alternatives to current methods.

CONCLUSIONS

Limitations of existing HICP methods are discussed and alternative development approaches to HICP measures are presented. The use of either discrete or continuous latent variable models would improve upon the psychometric characteristics of current HICP evidence. Examples are used to illustrate the benefits of latent variable models over traditional observed variable conceptualizations as the measurement of HICP continues to develop.

SIGNIFICANCE STATEMENT

This work takes the position that current methods of measuring high impact chronic pain (HICP) likely contain substantial error. We have endorsed an alternative approach for several psychometrically grounded reasons. We recommend that future work consider the discrete latent variable framework for dichotomous measures of HICP and the continuous latent variable framework for continuous measures of HICP. The paper provides illustrative examples of these methods for a different patient reported measure that is lacking a gold standard, much like HICP measures.

Application of the grading system for "nociplastic pain" in chronic primary and chronic secondary pain conditions: a field study

ABSTRACT

The concept "nociplastic pain" has been developed for patients with features of nociceptive system sensitization that are not explained as nociceptive or neuropathic. Here, we tested how well the recently published grading system differentiates between chronic primary and secondary pain conditions. We recruited patients with fibromyalgia (FMS, n = 41), complex regional pain syndrome (CRPS, n = 11), osteoarthritis (OA, n = 21), or peripheral nerve injury (PNI, n = 8). We used clinical history, pain drawings, quantitative sensory testing (QST), and questionnaires to classify their pains as possibly or probably "nociplastic." All patients with chronic primary pain exhibited widespread/regional pain not explainable by either nociceptive or neuropathic mechanisms. Widespread pain occurred in 12 patients with OA but was identified as nociceptive in 11 of 12. Regional pain occurred in 4 patients with PNI but was identified as neuropathic in 3 of 4. At this step, the grading system had 100% sensitivity and 93% specificity. Clinical evidence for pain hypersensitivity by QST, and history of hypersensitivity and mental comorbidities did not differentiate between chronic primary pain (QST: 36/52 = 69%, history: 43/52 = 83%) and secondary pain conditions (QST: 20/29 = 69%, history: 24/29 83%). Based on these data, specificity remained excellent (93%), but sensitivity dropped substantially (60%) due to lacking evidence for pain hypersensitivity in many patients with FMS. This low sensitivity suggests that the published grading system is not suitable for screening purposes. We suggest structural and content modifications to improve sensitivity, including placement of patient history before clinical examination and addition of a high tender point count as evidence for widespread pain hypersensitivity.

Preoperative glycaemic control, number of pain locations, structural knee damage, self-reported central sensitisation, satisfaction and personal control are predictive of 1-year postoperative pain, and change in pain from pre- to 1-year posttotal knee arthroplasty

PURPOSE

The aim of this study was to identify preoperative predictors for 1-year posttotal knee arthroplasty (TKA) pain and pre- to post-TKA pain difference in knee osteoarthritis (KOA) patients.

METHODS

From March 2018 to July 2023, this prospective longitudinal cohort study enrolled KOA patients awaiting TKA from four hospitals in Belgium and the Netherlands. Different biopsychosocial predictors were assessed preoperatively by questionnaires and physical examinations (input variables). The Knee injury and Osteoarthritis Outcome Score (KOOS) subscale pain was used to measure pain intensity. The absolute KOOS subscale pain score 1-year post-TKA and the difference score (ΔKOOS = 1-year postoperative - preoperative) were used as primary outcome measures (output variables). Two multivariable linear regression analyses were performed.

RESULTS

Two hundred and twenty-three participants were included after multiple imputation. Worse absolute KOOS subscale pain scores 1-year post-TKA and negative or closer to zero ΔKOOS subscale pain scores were predicted by self-reported central sensitisation, lower KOA grade and preoperative satisfaction, and higher glycated haemoglobin, number of pain locations and personal control (adjusted R2 = 0.25). Additional predictors of negative or closer to zero ΔKOOS subscale pain scores were being self-employed, higher preoperative pain and function (adjusted R2 = 0.37).

CONCLUSION

This study reports different biopsychosocial predictors for both outcomes that have filtered out other potential predictors and provide value for future studies on developing risk assessment tools for the prediction of chronic TKA pain.

PROTOCOL REGISTRATION

The protocol is registered at clinicaltrials.gov (NCT05380648) on 13 May 2022.

LEVEL OF EVIDENCE

Level II.

A pain research strategy for Europe: A European survey and position paper of the European Pain Federation EFIC

BACKGROUND

Pain is the leading cause of disability and reduced quality of life worldwide. Despite the increasing burden for patients and healthcare systems, pain research remains underfunded and under focused. Having stakeholders identify and prioritize areas that need urgent attention in the field will help focus funding topics, reduce 'research waste', improve the effectiveness of pain research and therapy and promote the uptake of research evidence. In this study, the European Pain Federation (EFIC) developed a Pain Research Strategy for Europe.

METHODS

The study used multiple methods, including literature searches, multidisciplinary expert debate, a survey and a final consensus meeting. The cross-sectional survey was conducted among 628 European pain researchers, clinicians, educators and industry professionals to obtain the rating and hierarchy of pain research priorities. The final consensus meeting involved a multidisciplinary expert panel including people with lived experience from 23 countries. The survey results guided discussions where top priorities were agreed.

RESULTS

Content analysis identified nine survey themes, of which five emerged as top priorities: (i) understand the pathophysiology of pain; (ii) understand and address comorbidities; (iii) critically assess current therapies; (iv) develop new treatments; and (v) explore the biopsychosocial impacts of pain. Physical, psychological and social approaches were prioritized at the same level as pharmacological treatments. The top priorities were endorsed by a multidisciplinary expert panel. The panel emphasized the importance of also clearly communicating the concepts of prediction, prevention self-management and personalized pain management in the final strategy.

CONCLUSIONS

The content of the final top research priorities' list reflects a holistic approach to pain management. The equal importance given to physical, psychological and social aspects alongside pharmacological treatments highlights the importance of a comprehensive biopsychosocial-orientated research strategy. The expert panel's endorsement of five top priorities, coupled with an emphasis on communicating the concepts of prediction, prevention, self-management and personalized pain management, provides a clear direction for future basic, translational and clinical research.

SIGNIFICANCE

EFIC has developed a Pain Research Strategy for Europe that identifies pain research areas deserving the most focus and financial support. Implementation and wide dissemination of this Strategy is vital to increase the conduct of urgent pain projects, pain research funding and the implementation of research findings into practice, to ultimately decrease the personal, societal and financial burden of pain.

Implementation-effectiveness of the power over pain portal for patients awaiting a tertiary care consultation for chronic pain: A pilot feasibility study

Background

The Power Over Pain (POP) Portal is a digital platform that provides people living with pain (PLWP) flexible access to chronic pain self-management resources.

Aims

To (1) determine the feasibility of an adequately-powered multisite trial of the POP Portal in tertiary settings; (2) understand the acceptability and usability of the POP Portal; and (3) explore clinical effectiveness among PLWP awaiting a first visit to a tertiary care pain clinic.

Methods

Mixed-methods pilot-feasibility study to inform a future definitive trial. Feasibility was assessed using recruitment and retention rates. Acceptability, usability, and patient outcomes were measured using validated surveys completed at baseline and 3-month follow-up, and semistructured interviews conducted after 3-month follow-up.

Results

Forty-one participants completed follow-up surveys and nine completed interviews. We reached a recruitment and retention rate of 83.75% and 61.19%, respectively. There was a reduction in pain interference (p = .024) and belief in a medical cure (p = .033) after using POP for 3 months. Surveys and interviews indicate PLWP were satisfied with the POP Portal, and it had good usability. Some participants indicated that POP was overwhelming, and certain resources were difficult to access, indicating that modifications could be made to improve ease of use.

Conclusions

The POP Portal was deemed acceptable with good usability; however, modification may be made for improvement. A definitive trial can proceed with enhancements to the portal, modification of the protocol, and close monitoring.

Establishing consensus on biopsychosocial factors associated with pediatric chronic pain: A modified Delphi study

A variety of factors are associated with the development and maintenance of chronic pain in children. Identifying modifiable factors associated with pediatric chronic pain is important to use them as target outcomes in the development and evaluation of interventions for the prevention and management of chronic pain. This study aimed to reach expert consensus on factors associated with pediatric chronic pain and their modifiability and population-level effect. Pediatric pain experts were questioned using a web-based two-round modified Delphi method. Two rounds of questions with Likert scaling were used to identify influencing factors (Round 1) and to reach consensus on each factor (Round 2) in terms of: 1) strength of association with chronic pain in children; 2) modifiability; and 3) population-level effect. An inductive approach was used to derive categories (ranging from 'very low' to 'very high') and subcategories (ranging from 'low' to 'high'). In total, 48 experts from 14 different countries completed Round 1, and 31 completed Round 2. A list of 47 factors was considered to be associated with pediatric chronic pain. Four factors (physical activity (PA), sedentary behavior (SB), pain-related school absence, and pain concept/knowledge of the child) were considered highly modifiable and three factors having a high population-level effect (PA, SB, and the child's depressive or negative emotional feelings). Expert consensus was established about modifiable and population-level factors associated with pediatric chronic pain through this web-based modified Delphi study, guiding target outcomes for its prevention and management. PERSPECTIVE: This article presents the results of a modified Delphi study with pediatric pain experts to gain consensus on factors associated with pediatric chronic pain. Relationship strength, modifiability, and population-level effect of associated factors were rated to identify areas of research priority and interventions aiming to reduce the development and maintenance of chronic pain in children.

Characterizing phenotypes and clinical and health utilization associations of young people with chronic pain: latent class analysis using the electronic Persistent Pain Outcomes Collaboration database

ABSTRACT

Using the Australiasian electronic Persistent Pain Outcomes Collaboration, a binational pain registry collecting standardized clinical data from paediatric ePPOC (PaedsePPOC) and adult pain services (AdultePPOC), we explored and characterized nationally representative chronic pain phenotypes and associations with clinical and sociodemographic factors, health care utilization, and medicine use of young people. Young people ≥15.0 and <25.0 years captured in PaedePPOC and AdultePPOC Australian data registry were included. Data from 68 adult and 12 paediatric pain services for a 5-year period January 2018 to December 2022 (first episode, including treatment information) were analysed. Unsupervised latent class analysis was applied to explore the existence of distinct pain phenotypes, with separate models for both services. A 3-phenotype model was selected from both paediatric and adult ePPOC data, with 693 and 3518 young people included, respectively (at least one valid indicator variable). Indicator variables for paediatric models were as follows: pain severity, functional disability (quasisurrogate "pain interference"), pain count, pain duration, pain-related worry (quasisurrogate "catastrophizing"), and emotional functioning; and, for adult models: pain severity, pain interference, pain catastrophizing, emotional functioning, and pain self-efficacy. From both services, 3 similar phenotypes emerged ("low," "moderate," "high"), characterized by an increasing symptom-severity gradient in multidimensional pain-related variables, showing meaningful differences across clinical and sociodemographic factors, health service utilization, and medicines use. Derived phenotypes point to the need for novel care models that differentially respond to the needs of distinct groups of young people, providing timely, targeted, age-appropriate care. To effectively scale such care, digital technologies can be leveraged to augment phenotype-informed clinical care.

Clinical characteristics and risk factors for acute abdomen in patients with abdominal lymphatic malformations

OBJECTIVE

The diagnosis of abdominal lymphatic malformations (ALMs) is often overlooked in clinical practice. However, reports in the literature about ALMs are limited to case reports and series with small sample sizes. This study aimed to review our currently available data to describe the clinical characteristics of ALMs and evaluate the risk factors for acute abdomen caused by ALMs.

METHODS

We reviewed the records of patients with ALMs who were diagnosed between December 2008 and January 2023 in our institution. The associations between acute abdomen and ALMs were analyzed based on single-factor and multivariate logistic regression analyses.

RESULTS

This study included 345 patients with pathologically confirmed ALMs, with a slight female predominance of 1:1.4. Approximately 39.1% (135/345) of patients were asymptomatic, and 24.6% (85/345) presented with acute abdomen. Among the ALMs in the cohort, 42.6% (147/345) were retroperitoneal lymphatic malformations (LMs). The maximal lesion dimensions in patients with acute abdomen and nonacute abdomen were 10.0 cm and 7.8 cm, respectively, with no significant difference based on multivariate analyses. Children were more likely to develop acute abdomen than adults were (P = .002; odds ratio, 5.128; 95% confidence interval, 1.835-14.326). ALMs accompanying acute abdomen were more common for lesions involving the small intestinal mesentery (P = .023; odds ratio, 2.926; 95% confidence interval, 1.157-7.400).

CONCLUSIONS

ALMs are rare with an insidious onset, and retroperitoneal LMs are the most common ALMs, followed by jejunal mesenteric LMs. Our retrospective analysis suggested that young age and small intestinal mesenteric lymphatic malformation are independent risk factors for acute abdomen with ALMs.

Effects of Combined Intrathecal Mesenchymal Stem Cells and Schwann Cells Transplantation on Neuropathic Pain in Complete Spinal Cord Injury: A Phase II Randomized Active-Controlled Trial

Neuropathic pain is a debilitating complication following spinal cord injury (SCI). Currently, effective treatments for SCI-induced neuropathic pain are highly lacking. This clinical trial aimed to investigate the efficacy of combined intrathecal injection of Schwann cells (SCs) and bone marrow-derived mesenchymal stem cells (BMSCs) in improving SCI-induced neuropathic pain. This study was a parallel-group, randomized, open-label, active-controlled phase II trial with two arms, including treatment and control groups. Patients with complete SCI-induced neuropathic pain in the treatment group received a single combined intrathecal injection of BMSCs and SCs. Study outcome measures were International SCI Pain Basic Data Set (ISCIPBDS) and World Health Organization (WHO) Quality of Life Assessment Instrument (WHOQOL-BREF). A total of 37 (55.2%) and 30 (44.8%) patients in the treatment and control groups were followed up for 6 months, respectively. Significant reductions in mean scores of interference items in the treatment group, including daily activities (P < 0.001), mood (P < 0.001), and sleep (P < 0.001), were found at 6 months after the injection compared with the control one. Similarly, pain frequency (P = 0.002), mean (P = 0.001), and worst (P = 0.001) numeric rating scale (NRS) pain intensity scores showed significant reductions in the treatment group after 6 months compared with the control one. Based on multiple regression analysis controlled for potential confounders, significant associations between changes in all outcome measures over the study period and the treatment group were found. This clinical trial indicated the efficacy of combined cell therapy in improving the neuropathic pain and quality of life in complete SCI patients. Future investigations should evaluate the effects of combination of this strategy with other existing therapies for SCI-induced neuropathic pain. This clinical trial was also registered prospectively at the Iranian Registry of Clinical Trials (IRCT20200502047277N8).

[Persistent spinal pain syndrome : Consideration of psychosocial risk factors]

The introduction of the term persistent spinal pain syndrome (PSPS), replacing the term failed back surgery syndrome (FBSS) has significantly changed diagnostic and treatment approaches of PSPS. There are multiple risk factors that may contribute to the development of PSPS. Accurately identifying individual risk factors is, therefore, crucial for patient-centered treatment planning. This article mainly focuses on patient-related psychosocial risk factors. Possibilities of evaluating these risk factors prior to spinal surgery in order to prevent PSPS from developing, as well as treatment options for established PSPS will be discussed.

Classification systems for chronic pelvic pain in males: a systematic review

OBJECTIVE

To systematically review the classification systems for male chronic pelvic pain (CPP).

METHODS

The Medical Literature Analysis and Retrieval System Online (MEDLINE), Excerpta Medica dataBASE (EMBASE), and Web of Science were searched. Any publication, with no restriction to publication date, was eligible. Publications had to propose a classification system for CPP in males or provide additional information of a system that had been identified. Systems were assessed with an adapted Critical Appraisal of Classification Systems tool.

RESULTS

A total of 33 relevant publications were identified, with 22 proposing an original classification system. Systems aimed to: (i) diagnose CPP and/or differentially diagnose CPP from other conditions, (ii) differentially diagnose subtypes within CPP, or (iii) identify features that could inform underlying mechanisms and/or treatment selection. Conditions referred to as chronic prostatitis/chronic pelvic pain syndrome and interstitial cystitis/bladder pain syndrome were most represented. Clinical signs/symptoms, pathoanatomical investigations, and presumed pain mechanisms were used for classification. Quality of systems was low to moderate, implying limitations to consider for their interpretation.

CONCLUSIONS

Many classification systems for CPP in males exist. Careful consideration of their intended purpose is required. Future work should examine whether outcomes for patients are improved when decisions are guided by their use.

Mental health risks in pregnancy and early parenthood among male and female parents following unintended pregnancy or fertility treatment: a cross-sectional observational study

BACKGROUND

Unintended pregnancy at higher risk of perinatal mood disorders; however, concurrent factors such as socioeconomic conditions may be more critical to mental health than pregnancy intention. Mental health risks among individuals undergoing fertility treatment are inconsistent. We investigated mental health risks during pregnancy and parenthood in parents who conceived unintentionally or through fertility treatment compared to those who conceived naturally and intentionally.

METHODS

We conducted a web-based study with 10,000 adults ≥ 18 years old, either pregnant or with a child aged < 2 years. Male and female respondents weren't couples. We analyzed 1711 men and 7265 women, after filtering out invalid responses. We used a questionnaire including conception methods (e.g., naturally conceived intended/unintended pregnancies, fertility treatment such as scheduled intercourse or ovulation inducers [SI/OI], intrauterine insemination [IUI], and in-vitro fertilization or intracytoplasmic sperm injection [IVF/ICSI]) and mental health risks (e.g., psychological distress, chronic pain, death fantasies). Using a modified Poisson regression, we estimated relative risks (RR [CI]) for mental health risks compared to those with intended pregnancies.

RESULTS

Unintended pregnancy showed higher mental health risks during pregnancy in both genders, with women having significantly higher psychological distress, chronic pain, and death fantasies (RR 1.63 [1.05-2.54], RR 1.63 [1.14-2.33], and RR 2.18 [1.50-3.18], respectively). Women's death fantasies risk remained high in parenthood: RR 1.40 (1.17-1.67). In relation to fertility treatments, men using SI/OI during their partner's pregnancy showed higher mental health risks, especially for chronic pain (RR 1.75 [1.01-3.05]). Men who underwent IUI showed higher mental health risks during parenthood, notably death fantasies (RR 2.41 [1.13-5.17]). Pregnant women using SI/OI experienced higher mental health risks, with a significant risk of chronic pain (RR 1.63 [1.14-2.33]). Pregnant women using IVF/ICSI had a significantly lower risk of chronic pain (RR 0.44 [0.22-0.87]), but women who used IVF/ICSI had a significantly higher risk of death fantasies during parenthood (RR 1.40 [1.04-1.88]).

CONCLUSIONS

Mental health risks vary by parenting stage (pregnancy or early parenthood) and gender, especially for those who conceived unintentionally or through fertility treatment. Both stages require adaptable mental health support for all parents.

TRIAL REGISTRATION

N/A (non-interventional study).

"When you're in pain you do go into your shell" A community-based pain management programme co-designed with Māori whānau to address inequities to pain management - A qualitative case study

Chronic or persistent non-cancer pain disproportionately affects Māori - the Indigenous population of Aotearoa New Zealand (NZ) and their whānau (family and significant others). In a previous study with a Māori community service provider - Tū Kotahi Māori Asthma and Research Trust - Tū Kotahi, identified a need for a Kaupapa Māori (by Māori, for Māori) pain management programme (PMP) with embedded principles of Whānau Ora (care focusing on the wellbeing of the individual and their significant others as a collective). Using a qualitative case-study design, the main aims were to describe (1) the implementation of a community-based, whānau-focused PMP; (2) the participant experiences of the programme. This is community-based participatory action research guided by a Māori-centred research approach. Based on our previous co-design study with Tū Kotahi, a 6-week PMP (July - August 2021) was implemented at Kokiri Marae (community meeting place). Eight whānau living with persistent pain participated in the 6 sessions led by our Māori community partner and a pain management physiotherapist including a dedicated session on Rongoā Māori (Māori traditional treatment). Supporting resources were co-developed with our community partner, pain service clinicians, a Māori Health literacy expert, and a Māori illustrator. On completion, whānau reported enhanced confidence towards managing pain with "more tools to manage". The role of meaningful relationships, co-design, use of metaphors, and inclusion of traditional treatments - Rongoā were key aspects for the successful implementation. This initiative provides an exemplar for community and mainstream pain service partnership to address inequities in accessing pain management services for Māori. PERSPECTIVE: This study explains the key cultural processes of implementing a community-based pain management programme for Māori with persistent pain in Aotearoa New Zealand. The principles from our engagement could be applicable globally to engage with Indigenous and culturally and linguistically diverse communities with persistent pain to address longstanding health inequities.

Electroacupuncture ameliorates inflammatory pain through CB2 receptor-dependent activation of the AMPK signaling pathway

BACKGROUND

Chronic inflammatory pain is a pervasive condition, and electroacupuncture (EA) is an effective treatment, but its mechanisms are not fully understood. AMP-activated protein kinase (AMPK), a key energy sensor, is involved in pain relief and EA's effects. EA may work by increasing endocannabinoids, upregulating CB2 receptors (CB2R), and stimulating β-endorphin (β-END). This study tests if EA activates AMPK via CB2R to modulate β-END and reduce pain.

METHODS

The inflammatory pain model was established with Complete Freund's adjuvant (CFA), and EA was administered daily for six consecutive days, targeting the acupoints "Zusanli" (ST36) and "Shangjuxu" (ST37). Pain sensitivity was evaluated using Von Frey filaments for mechanical thresholds and a hot plate for thermal thresholds. Ultra-high Performance Liquid Chromatography Tandem Mass Spectrometry (UPLC-MS/MS) was used to quantitatively determine the levels of endocannabinoids 2-arachidonoylglycerol (2-AG) and anandamide (AEA). The expression levels of the CB2R and β-END were measured by Western blotting, along with the activation of AMPK. Immunofluorescence double-labeling was applied to visualize AMPK activation and β-END expression within CD68-positive macrophages. The study encompassed both wild-type and CB2R gene knockout mice, elucidating the role of CB2R in EA-induced AMPK activation.

RESULTS

CFA-induced inflammatory pain model mice exhibited mechanical allodynia and thermal hyperalgesia. EA activated AMPK in the inflamed skin tissue when it exerted analgesic effect on the inflammatory pain. Pre-administration of the AMPK inhibitor Compound C significantly inhibited the effect of EA on pain relief. EA elevated β-END expression in inflamed skin tissue, which was reversed by Compound C, indicating that AMPK has a regulatory role in EA inducing β-END expression. In addition, EA significantly upregulated the levels of 2-AG, AEA and the expression of CB2Rs in the inflamed skin tissue compared with the CFA group. In wild-type mice, EA activates AMPK in macrophages, while CB2 knockout reduced EA's ability to activate AMPK in these cells.

CONCLUSION

EA activates AMPK through CB2R, enhancing β-END expression in inflamed skin to alleviate inflammatory pain. This study reveals a new link between endocannabinoids, endorphins, and AMPK in analgesic effects of EA, highlighting the CB2R-AMPK-β-END pathway.

Global and regional trends and projections of chronic pain from 1990 to 2035: Analyses based on global burden of diseases study 2019

Background

Chronic pain poses a significant public health challenge. We present the global and regional data on Prevalence, Incidence and Years Lived with Disability (YLDs) for Chronic pain from the Global burden of disease (GBD) study 2019 data and analyze their associations with Socio-demographic index (SDI), age, and gender, and the future trends from 2020 to 2035.

Methods

Regional trends in the burden of chronic pain and its association with age, gender, and SDI were assessed from 1990 to 2019. Joinpoint analysis was employed to describe trends in chronic pain burden across different SDI regions. Additionally, the Bayesian Age-Period-Cohort model (BAPC) was used for predicting future trends. Age-standardized rates (ASRs) of prevalence, incidence, and YLDs were employed to quantify the burden of chronic pain.

Results

Between 1990 and 2019, a significant increase was observed in global prevalence and YLDs rates of chronic pain. Higher rates were found among females, whereas a faster rise was noted among males. Notably, Low Back Pain (LBP) and Migraine accounted for predominant YLDs globally, particularly among those aged 75 and above. A notable prevalence of Tension-type Headache (TTH) was observed among younger populations. Furthermore, ASRs for chronic pain were highest in high-SDI regions. Projections suggest an increase in headache ASRs globally for both genders from 2020 to 2035.

Conclusion

From 1990 to 2019, the global burden of chronic pain increased significantly, with projections indicating a continued rise in headache burden over the next 15 years, underscoring the need for heightened attention to these issues.

The Brain Waves During Reaching Tasks in People with Subacute Low Back Pain: A Cross-Sectional Study

Subacute low back pain (sLBP) is a critical transitional phase between acute and chronic stages and is key in determining the progression to chronic pain. While persistent pain has been linked to changes in brain activity, studies have focused mainly on acute and chronic phases, leaving neural changes during the subacute phase-especially during movement-under-researched. This cross-sectional study aimed to investigate changes in brain activity and the impact of pain intensity in individuals with sLBP during rest and reaching movements. Using a 28-electrode EEG, we measured motor-related brain waves, including theta, alpha, beta, and gamma oscillations. Transitioning from rest to movement phases resulted in significant reductions (> 80%) in mean power across all frequency bands, indicating dynamic brain activation in response to movement. Furthermore, pain intensity was significantly correlated with brain wave activity. During rest, pain intensity was positively correlated with alpha oscillation activity in the central brain area (r = 0.40, p < 0.05). In contrast, during movement, pain intensity was negatively correlated with changes in brain activity (r = -0.36 to -0.40, p < 0.05). These findings suggest that pain influences brain activity differently during rest and movement, underscoring the impact of pain levels on neural networks related to the sensorimotor system in sLBP and highlighting the importance of understanding neural changes during this critical transitional phase.

Physical Therapist-Led Initiatives for the Prevention and Improvement of Chronic Pain Among Workers: A Case Study of Hosting Workshops Based on Survey Results in a Corporate Setting

Industrial physical therapy (IPT) interventions by physical therapists can enhance labor productivity. However, in Japan, there is a scarcity of case studies involving corporate visits, questionnaire-based data, and insights into corporate demands. Addressing this gap is vital for improving presenteeism related to chronic pain and increasing employees' health literacy, thereby advancing corporate health management. This case study evaluates the effectiveness of a workshop aimed at preventing and reducing chronic pain among employees in the Development Department of Company A, an information technology (IT) firm. The research employed pre- and post-survey questionnaires, workshop interventions, and meetings with corporate management to assess the current state of musculoskeletal chronic pain and productivity losses and to verify the intervention's effectiveness. Approximately 50 participants attended the workshop in person, while around 30 participated online, totaling 80 attendees. A total of 56 (51 men and 5 women) individuals responded to the pre-workshop questionnaire, and 28 responded to the post-workshop questionnaire. The age distribution of the 56 pre-survey respondents was as follows: 9 in their twenties, 13 in their thirties, 22 in their forties, and 12 aged 50 and older. Preliminary survey results showed that 55.4% of participants experienced chronic pain in at least one body part. The average presenteeism value was 82.8% (standard deviation = 16.8). It was also found that literacy regarding appropriate pain management strategies was low. An independent t-test comparing literacy scores based on the presence or absence of pain showed no significant differences (p = 0.34). Additionally, a one-way ANOVA conducted to examine differences across four age groups revealed no significant differences (F = 0.934, p = 0.431). Results from the post-workshop questionnaires indicated that more than 70% of the employees experienced an increase in understanding and satisfaction, with positive feedback on the improvement of knowledge about chronic pain mechanisms and posture. However, there were also requests for more interactive communication and a desire to learn more about specific care methods, suggesting the need to provide interventions tailored to appropriate stages of preventive medicine.

A correlation study between blood glucose fluctuation and chronic pain in the older people with type 2 diabetes mellitus

OBJECTIVES

To investigate the correlation between blood glucose fluctuation parameters and other clinical data with chronic pain in older patients ( ≧ 60 years) with type 2 diabetes mellitus (T2DM), as well as evaluating the predictive value of risk of these parameters for chronic pain.

METHODS

Clinical data were collected from 60 older patients with T2DM undergoing chronic pain who were hospitalized in the Department of Geriatric Endocrinology at the First Affiliated Hospital of Anhui Medical University. Pain scores using the numeric rating scale (NRS) were administered to all study participants by a dedicated person. Based on their pain scores, patients were categorized into two groups: mild pain group (NRS ≤ 5, n = 28) and severe pain group (NRS > 5, n = 32). Blood glucose levels were continuously monitored using the Continuous Glucose Monitoring System (CGMS). Spearman correlation analysis was performed to investigate the correlation between pain scores and blood glucose fluctuation parameters, as well as other clinical data of concern. Comparing general clinical information and relevant data recorded by CGMS between the two groups. Binary logistic regression was used to identify factors influencing the severity of chronic pain in old patients with T2DM combined with chronic pain. Additionally, the predictive value of Mean Amplitude of Glycemic Excursions (MAGE), Coefficient of Variation (CV), and Time in Range (TIR) for chronic pain severity was assessed using Receiver Operating Characteristic (ROC) curve analysis.

RESULTS

Spearman correlation analysis revealed positive correlations between pain scores and the following variables: gender, age, duration of diabetes, duration of pain, MAGE, CV, mean blood glucose (MBG), standard deviation (SD), Mean of Daily Differences (MODD), and the highest glucose level. Conversely, pain scores were negatively correlated with red blood cell (RBC) count, hemoglobin (Hb), estimated glomerular filtration rate (eGFR). There were statistically significant differences in gender, age, disease duration, pain duration, Hb, eGFR, MAGE, CV, TIR, MBG, SD, MODD, and highest blood glucose values between the two groups. The gender, age, duration of diabetes, duration of pain, Hb, eGFR, MAGE, TIR, CV, MBG, SD, and MODD were identified as the risk factors for the severity of chronic pain in older T2DM patients by using binary logistic regression analysis. ROC curve analysis showed that the area under the curve for MAGE was 0.741 (sensitivity: 53.1%, specificity: 89.3%), for CV it was 0.668 (sensitivity: 40.6%, specificity: 89.3%), and for TIR it was 0.763 (sensitivity: 67.9%, specificity: 84%).

CONCLUSION

The chronic pain is strongly correlated with blood glucose fluctuation parameters in older patients with T2DM. This work shows that those indicators of blood glucose fluctuations can be used for predicting chronic pain level in older T2DM patients, providing a potential methodology for rapid evaluation of chronic pain.

CLINICAL TRIAL NUMBER

ChiCTR1800019107.