Pain Reports最新文献

Introduction: Psychosocial function in people with chronic low back pain (cLBP) is often impaired, indicating poor well-being. Fear-avoidance beliefs (FAB) are common concomitants of cLBP. Fear-avoidance beliefs are gaining attention as a potential prognostic factor for chronification and resulting disability in cLBP. This article aims to examine the associations of back function with FAB.

Methods: This study presents data from a cohort study (DRKS00027907). In the present cross-sectional analyses, we included 914 participants (480 nonchronic LBP [ncLBP], 227 cLBP, 207 asymptomatic). Fear-avoidance beliefs were assessed using the fear-avoidance belief questionnaire (FABQ). The association between the FAB and clinical measures (Ott and Schober test, the sit-to-stand test [STS], and the finger-floor distance [FFD]) were analyzed. Back shape and function were also measured using a noninvasive device. The association between FABQ scores and clinical measures was assessed using age, body mass index, sex, and pain intensity-adjusted multiple linear regression models.

Results: Associations between FAB and both clinical (Ott, Schober, STS, FFD) and noninvasive device measures were small. All relevant clinical measures were attenuated in individuals with elevated FAB.

Discussion: We were able to demonstrate the association of both back shape and function in both clinical tests and noninvasive device measurements with self-reported fear-avoidance beliefs. However, the effect sizes were small. This may be attributed to the different assessment methods (objective vs self-report), resulting in reduced common method variance. In addition to the FAB, there may be other factors (eg, altered neuronal pathways; actual avoidance behavior such as reduced physical activity) that contribute to functional impairment.

Introduction: This study investigates the epigenetic landscape underlying painful intervertebral disk (IVD) degeneration in a single subject with a history of low back pain (LBP). Intervertebral disk degeneration is associated with LBP in some individuals; however, there is often a discrepancy between degeneration and pain. We hypothesize that DNA methylation, an epigenetic mechanism previously linked to discogenic LBP, is dysregulated in symptomatic vs asymptomatic IVDs.

Objectives: Identify differentially methylated genes and pathways in symptomatic vs asymptomatic IVDs.

Methods: Three lumbar IVDs with similar degeneration severity were tested prior to surgery by discography to identify symptomatic IVDs. Methylation analysis was performed on ∼935,000 cytosine guanine dinucleotide sites on nucleus pulposus DNA. We explored differential methylation and pathway enrichment on cytosine guanine dinucleotide sites located within the promoter regions of genes.

Results: Two IVDs (L3/L4 and L4/L5) evoked pain ratings of 10/10 and 8/10, one IVD (L5/S1) scored 0/10. DNA methylation differed between symptomatic and asymptomatic IVDs. Several identified genes have roles in extracellular matrix remodeling. Other differentially methylated genes were related to immunomodulation and ion channel function. Finally, several long noncoding RNA genes were identified, encouraging further exploration into these regulatory molecules. Enriched pathways were associated with immune response, hormonal regulation, nervous system development, and musculoskeletal development and remodeling.

Conclusion: This case study provides a promising list of candidate genes for therapeutic development for discogenic LBP and suggests a role for DNA methylation in the development of symptomatic vs asymptomatic IVD degeneration, calling for further research to validate and expand these findings.

Introduction: Ocular pain is a common complaint to eye care providers, associated with a variety of ocular conditions, among which dry eye disease (DED) is affecting millions of people worldwide. Despite being highly prevalent, ocular pain is not managed adequately in the clinic.

Objectives: The aim of this study was to investigate the analgesic potential of neurokinin-1 receptor (NK1R) antagonism in DED.

Methods: Dry eye disease was induced in mice, and an NK1R antagonist L-733,060 was topically administered twice daily throughout the study for 14 days. Hyperalgesia and allodynia were assessed using the eye-wiping test and palpebral ratio measurements. Corneas were collected for measuring substance P (SP) levels by enzyme-linked immunosorbent assay (ELISA) and imaging nerves by immunostaining. Trigeminal ganglions (TG) were collected to determine SP levels by ELISA and transient receptor potential cation channel subfamily V member 1 (TRPV1), transient receptor potential cation channel subfamily M (melastatin) member 8, c-Fos, and activating transcription factor 3 (ATF3) mRNA levels by real-time polymerase chain reaction.

Results: Treating DED mice with L-733,060 resulted in a significant reduction in eye wipe behavior, a significant increase in palpebral ratio, and significant decreases in SP levels in both the cornea and TG compared with the vehicle-treated group. In addition, NK1R antagonist treatment significantly suppressed the upregulation of TRPV1, ATF3, and c-Fos and prevented corneal nerve loss.

Conclusion: Neurokinin-1 receptor antagonism effectively reduced ocular nociception, decreased neuronal activation, and preserved corneal nerves in mice with DED. These findings suggest that blockade of SP signaling pathway is a promising therapeutic strategy for managing DED pain.

Introduction: Factors contributing to individual differences in knee osteoarthritis remain elusive. Dispositional traits and socioeconomic status are independent predictors of mental and physical health, although significant variability remains. Dispositional traits serve as the biological interface for life experiences.

Objectives: We investigate group differences based on dispositional traits and poverty status, specific to (1) pain intensity and functional limitations and (2) biological measures, a clinical composite and brain age.

Methods: Adults aged 45 to 85 years with knee pain associated with chronic musculoskeletal pain provided information on demographics, socioeconomic and psychosocial factors, pain, and physical function. Kellgren-Lawrence scores were determined from knee radiographs, the clinical composite from fasting blood draws, and brain age from MRI data.

Results: One hundred seventy-three individuals participated in the study. Of those, 117 had protective dispositional traits (81 above poverty/36 in poverty), and 56 had vulnerable dispositional traits (24 above poverty/32 in poverty). With sex, study site, Kellgren-Lawrence score, and age/or image quality as covariates, significant group differences were observed across clinical pain (P < 0.001), functional limitations (P ≤ 0.001), and brain age (P ≤ 0.002) measures. Although not significant, the clinical composite measure aligned with the other outcome measures and demonstrated the hormesis inverted U pattern.

Conclusions: Groups based on dispositional traits and socioeconomic status explain differing clinical outcomes. Consistent with the allostatic load and hormesis inverted U models, one group was in an adaptive health status, 2 groups were showing signs of developing load, and the fourth group showing signs of overload, at risk of worse health outcomes.

Introduction: Interpretation and utilization of qualitative feedback from participants has immense value for program evaluation. Reliance on only quantitative data runs the risk of losing the lived patient experience, forcing their outcomes to fit into our predefined objectives.

Objectives: Using large language models (LLMs), program directors may begin to employ rich, qualitative feedback expediently.

Methods: This study provides an example of the feasibility of evaluating patient responses (n = 82) to Empowered Relief, a skill-based pain education class using LLMs. We utilized a dual-method analytical approach, with both LLM-assisted and supported manual thematic review.

Results: The thematic analysis of qualitative data using ChatGPT yielded 7 major themes: (1) Use of Specific Audiofile; (2) Mindset; (3) Technique; (4) Community and Space; (5) Knowledge; (6) Tools and Approaches; and (7) Self-awareness.

Conclusion: Findings from the LLM-derived analysis provided rich and unexpected information, valuable to the program and the field of pain psychology by employing the set of patients' own words to guide program evaluation. Program directors may benefit from evaluating treatment outcomes on a broader scale such as this rather than focusing solely on improvements in disability. These insights would only be uncovered with open-ended data, and although potentially more insights could emerge with the help of a qualitative research team, ChatGPT offered an ergonomic solution.

Introduction: Alexithymia is elevated in chronic pain and relates to poor pain-related outcomes. However, despite concerns from other clinical populations, the psychometric properties of alexithymia measures have not been rigorously established in chronic pain.

Objective: This study examined the psychometric properties of the Toronto Alexithymia Scale-20 Item (TAS-20) and the Perth Alexithymia Questionnaire (PAQ) in adults with chronic pain.

Methods: An online sample of adults with chronic pain across the United States (N = 1453) completed the TAS-20, PAQ, and related questionnaires at baseline, 3-month follow-up, and 12-month follow-up.

Results: Both measures showed good temporal stability, convergent validity (with emotion regulation scores), divergent validity (with depression and anxiety scores), and criterion validity. Some concerns were raised about the TAS-20: the original 3-factor structure showed a poor model fit; the Externally Oriented Thinking subscale of the TAS-20 had poor factor loadings and unacceptable internal consistency; and, we identified several TAS-20 items that may slightly inflate the predictive validity of the TAS-20 on pain-related outcomes. The original 5-factor structure of the PAQ showed a good fit; each PAQ subscale had good factor loadings and excellent internal consistency.

Conclusions: Both the TAS-20 and PAQ had psychometric strengths. Our data raised some concern for the use of TAS-20 subscales; the PAQ may be a psychometrically stronger option, particularly for investigators interested in alexithymia subscale analysis in people with chronic pain.

Introduction: Pregabalin, which acts on the α₂δ-1 subunit of voltage-gated calcium channels, relieves ≥50% of pain in a third of individuals with fibromyalgia. Thus far, preclinical studies of pregabalin have predominantly used male animals.

Objectives: The purpose of our study was to investigate potential sex differences in the analgesic efficacy of pregabalin that may contribute to disparities in human outcomes.

Methods: We used a mouse model of chronic widespread muscle pain (CWP) to test the effects of pregabalin on muscle hyperalgesia, nonreflexive pain, and motor behaviors. The CWP pain model combines 2 pH 4.0 saline injections, spaced 5 days apart, into the gastrocnemius muscle and produces bilateral muscle hyperalgesia. Furthermore, we explored sex differences in the mRNA and protein expression of the α₂δ-1 subunit of voltage-gated calcium channels in the dorsal horn of the spinal cord and dorsal root ganglia after development of CWP.

Results: Pregabalin fully attenuated muscle hyperalgesia bilaterally in male but not female mice with equal motor deficits produced in both sexes. In addition, using the conditioned place preference test, mice of both sexes with CWP spent significantly more time in the pregabalin-paired chamber compared with baseline, but not significantly greater than pain-free controls. Chronic widespread muscle pain produced no changes in α₂δ-1 subunit mRNA or protein expression in the dorsal horn of the spinal cord or dorsal root ganglia in either sex.

Conclusion: Overall, these findings indicate pregabalin may be more effective in treating CWP in males, but the factors leading to these differences are not fully understood.

Introduction: Manual therapy refers to a range of hands-on interventions used by various clinical professionals, such as osteopaths, osteopathic physicians, chiropractors, massage therapists, physiotherapists, and physical therapists, to treat patients experiencing pain.

Objectives: To present existing evidence of mechanisms and clinical effectiveness of manual therapy in pain.

Methods: This Clinical Update focuses on the 2023 International Association for the Study of Pain Global Year for Integrative Pain Care. Current models of manual therapy and examples of integrative manual therapy are discussed.

Results: The evolution of concepts in recent years are presented and current gaps in knowledge to guide future research highlighted. Mechanisms of manual therapy are discussed, including specific and contextual effects. Findings from research on animal and humans in manual therapy are presented including on inflammatory markers, fibrosis, and behaviours. There is low to moderate levels of evidence that the effect sizes for manual therapy range from small to large for pain and function in tension headache, cervicogenic headache, fibromyalgia, low back pain, neck pain, knee pain, and hip pain.

Conclusion: Manual therapies appear to be effective for a variety of conditions with minimal safety concerns. There are opportunities for manual therapies to integrate new evidence in its educational, clinical, and research models. Manual therapies are also well-suited to fostering a person-centred approach to care, requiring the clinician to relinquish some of their power to the person consulting. Integrated manual therapies have recently demonstrated a fascinating evolution illustrating their adaptability and capacity to address contemporary societal challenges.

Chronic pain is a debilitating health problem affecting 20 million Americans annually. Most patients with chronic pain report negative impacts on daily function and quality of life, which can result in devastating emotional and financial stress. Although the causes of chronic pain remain elusive, there is increasing interest in sensitivity to everyday sensory stimuli as it relates to chronic pain, potentially serving as an indirect marker of altered central nervous system sensory processing. However, sensitivity to multiple sensory inputs, eg, bright lights, certain fabrics, loud noises, etc, is described using multiple terminologies. The lack of a common vocabulary makes it difficult to find and summarize related discoveries, potentially inhibiting scientific progress. Thus, the purpose of this scoping review was to identify and characterize the terminology used in publications assessing some form of multisensory sensitivity as it relates to pain (eg, a pain cohort or pain sensitivity). Our review of 6 databases (PubMed, Scopus, Embase, CINAHL, PsycINFO+, and Cochrane) comprehensively cataloged peer-reviewed studies published through March 2023 in this domain. Of 12,841 possible studies identified, 92 met all inclusion criteria, with over 80% being published in the last decade. A wide range of terminology has been used for this construct, likely in part a result of the many different professional disciplines represented. These results provide valuable insights for future development of a standardized vocabulary and serve as a resource to aid future investigators of multisensory sensitivity and pain in their study design.