Frontiers in pain research (Lausanne, Switzerland)最新文献

Globally, humans rely on cattle for food production; however, there is rising societal concern surrounding the welfare of farm animals. From a young age, cattle raised for dairy and beef production experience pain caused by routine management procedures and common disease conditions. The fundamental mechanisms, nociceptive pathways, and central nervous system structures required for pain perception are highly conserved among mammalian species. However, there are limitations to a comparative approach to pain assessment due to interspecies differences in the expression of pain. The stoicism of prey species may impede pain identification and lead to the assumption that cattle lack pain sensitivity. This highlights the importance of establishing validated bovine-specific indicators of pain-a prerequisite for evidence-based pain assessment and mitigation. Our first objective is to provide an overview of pain pathophysiology to illustrate the importance of targeted analgesia in livestock medicine and the negative welfare outcomes associated with unmitigated pain. This is followed by a review of available analgesics, the regulations governing their use, and barriers to implementation of on-farm pain management. We then investigate the current research undertaken to evaluate the pain response in cattle-a critical aspect of the drug approval process. With an emphasis on emerging research in animal cognition and pain pathology, we conclude by discussing the significant influence that pain has on cattle welfare and areas where further research and modified practices are indicated.

Approximately 356 million limb amputations are performed globally every year. In 2005, the prevalence of limb loss in the United States was 1.6 million people; and it is estimated to increase to 3.6 million by 2050. Many post-amputation patients experience chronically altered sensations and pain associated with the amputation, such as phantom limb pain. The risk factors for phantom limb pain are widely debated in the literature due to the heterogeneity of the population being studied. This review will highlight both the non-operative and operative risk factors for phantom limb pain.

Introduction: Nociplastic pain (NP), classified as a third type of pain alongside nociceptive and neuropathic pain, is chronic pain arising from the amplification of nociceptive stimuli through central sensitization, despite the absence of tissue damage, sensory nerve damage, or disease. An important clinical feature of NP is that it is not only associated with pain but also with sensory hypersensitivity to sound and light and cognitive dysfunction, including mood and attention disorders. Recent studies have suggested that depression and developmental disorders, such as attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD), coexist with NP at high frequency. Additionally, cognitive impairment in individuals with NP may be associated with these psychiatric comorbidities. However, to our knowledge, there are no reports on (1) multidimensional evaluation and diagnostic details of abdominal NP in adults with ADHD/ASD; (2) how ADHD drugs and antidepressants are administered when ADHD and depression coexist with NP; and (3) how central sensitization, brain function, and family relationship problems underlying NP are altered by treatments of ADHD and depression.

Case presentation: Herein, we present the case of a 51-year-old woman with abdominal NP. She developed severe right lower abdominal pain and underwent a thorough medical examination; however, the physical, medical cause remained unknown, making treatment challenging. Additionally, she took time off work as she began to complain of insomnia and anxiety. She was referred to our pain center, where a diagnosis of depression, ADHD, and ASD was confirmed, and treatment with ADHD medication was initiated. While ADHD medications alone did not yield sufficient improvement, a combination of methylphenidate and the antidepressant venlafaxine eventually led to improvements in abdominal NP, depression, ADHD symptoms, central sensitization, and family relationship issues. During treatment, cerebral blood flow in the anterior cingulate, prefrontal, and parietal cortices also improved.

Conclusion: The treatment of comorbid depression is important while treating NP, and venlafaxine may be effective, especially in cases of comorbid ADHD/ASD. Screening for developmental disorders and depression is required in patients with abdominal NP.

Objective: Quantitative sensory testing is often used to investigate pain in the context of experimental and clinical research studies. However, many of the devices used for QST protocols are only available in resource rich environments, thereby inadvertently limiting the possible pool of participants. Development of remote protocols for appropriate QST measures has the potential to reduce barriers to participation in research.

Methods: Participants with insomnia and Crohn's disease were recruited as part of a clinical trial. We adapted a remote version of the cold pressor test for use during telehealth-based study assessments. Herein, we present data from the baseline assessments including an assessment of feasibility and acceptability of the task.

Results: 100% of participants (N = 28) were able to complete the remote cold pressor test using a combination of materials from their homes and mailed by the study team. Temperature changes during the test were minimal and fairly evenly balanced between increases and decreases. Correlations between submersion time and both general and disease specific pain trended toward significance.

Conclusions: We demonstrated that a remote version of the cold pressor test is feasible and acceptable in a clinical population and provided a step-by-step protocol for administration to facilitate use in other studies.

Background: While numeric scales to represent pain intensity have been well validated, individuals use various conceptualizations when assigning a number to pain intensity, referred to as pain rating schema. The 18-item Pain Schema Inventory (PSI-18) quantifies pain rating schema by asking for numeric values for multiple mild, moderate or severe pain conditions. This study aimed to assess the validity and reliability of a shortened form of the PSI, using only 6 items (PSI-6).

Methods: A secondary analysis was performed on two existing datasets. The first (n = 641) involved a community-based population that completed the PSI-18. The second (n = 182) included participants with chronic pain who completed the PSI-6 twice, one week apart. We assessed face validity, convergent validity, offset biases, test-retest reliability, and internal consistency of the PSI-6 compared to the PSI-18.

Results: Both the PSI-18 and PSI-6 demonstrated excellent face validity. The PSI-6 demonstrated excellent convergent validity relative to the PSI-18, with correlations from r = 0.88 to 0.92. Bland-Altman plots revealed offset biases near zero (< 0.22 on 0-10 scale) across all categories of mild, moderate, severe and average pain. Internal consistency was excellent, with Cronbach's Alpha = 0.91 and 0.80, for PSI-18 and PSI-6 respectively. Test-retest reliability of the PSI-6 was high with correlations from r = 0.70-0.76.

Conclusion: The PSI-6 is a valid and reliable tool to assess pain rating schema with reduced subject burden, to better interpret individuals' pain ratings and adjust for inter-individual variability.

[This corrects the article DOI: 10.3389/fpain.2024.1374929.].

Introduction: Chronic musculoskeletal (MSK) pain is prevalent in older adults and confers significant risk for loss of independence and low quality of life. While obesity is considered a risk factor for developing chronic MSK pain, both high and low body mass index (BMI) have been associated with greater pain reporting in older adults. Measures of body composition that distinguish between fat mass and lean mass may help to clarify the seemingly contradictory associations between BMI and MSK pain in this at-risk group.

Methods: Twenty-four older adults (mean age: 78.08 ± 5.1 years) completed dual-energy x-ray absorptiometry (DEXA), and pain measures (Graded Chronic Pain Scale, number of anatomical pain sites, pressure pain threshold, mechanical temporal summation). Pearson correlations and multiple liner regression examined associations between body mass index (BMI), body composition indices, and pain.

Results: Significant positive associations were found between number of pain sites and BMI (b = 0.37) and total fat mass (b = 0.42), accounting for age and sex. Total body lean mass was associated with pressure pain sensitivity (b = 0.65), suggesting greater lean mass is associated with less mechanical pain sensitivity.

Discussion: The results from this exploratory pilot study indicate lean mass may provide additional resilience to maladaptive changes in pain processing in older adults, and highlights the importance of distinguishing body composition indices from overall body mass index to better understand the complex relationship between obesity and MSK pain in older adults.

Introduction: This study aimed to assess the percentage of patients treated according to the European Society for Medical Oncology (ESMO) 2018 guidelines for breakthrough cancer pain (BTcP) and the impact of guidelines adherence on patients' quality of life (QoL).

Methods: Adult opioid-tolerant patients diagnosed with BTcP and locally advanced or recurrent metastatic cancer with a life expectancy of >3 months prospectively were included. Patients were followed up for 28 days.

Results: Of 127 patients included, 37 were excluded due to the impossibility to establish adherence to the ESMO guidelines. Among the evaluable patients [51.1% female; with mean (SD) age of 66.4 (11.8) years], all were adherent. BTcP was diagnosed by the Association for Palliative Medicine algorithm in 47.8% of patients and by clinical experience in 52.2% of patients. The mean number of daily BTcP episodes ranged between 1 and 8, with a mean (95% CI) severity of 7.3 (7.0; 7.6) at week 0 and 6.2 (5.8; 6.6) at week 4. Time to maximum pain intensity was 3-15 min in 52.2% of patients, and BTcP lasted 30-60 min in 14.4% of patients at week 0 and 4.4% of patients at week 4. Mean (95% CI) treatment effectiveness was 6.6 (6.1; 7.1) at week 0 and 7.4 (7.0; 7.8) at week 4. Median (Q1-Q3) patients' global impression of clinical condition was 4.0 (4.0-4.0) at week 0 and 3.0 (2.0-3.0) at week 4.

Conclusion: A clear BTcP assessment and strict follow-up could be crucial to guidelines adherence and for patient's QoL.

Introduction: Chemotherapy-induced peripheral neuropathy (CIPN) is a debilitating side effect of cancer treatment that significantly impacts patients' quality of life. This study investigated the effects of targeting metabolic pathways on bortezomib-induced neuropathic pain and tumor growth using a Lewis lung carcinoma (LLC) mouse model, while exploring potential sex differences.

Methods: Male and female C57BL/6J mice were implanted with LLC cells and treated with bortezomib alone or in combination with metformin, dichloroacetate (DCA), or oxamate. Tactile allodynia was assessed using von Frey filaments. Tumor volume and weight were measured to evaluate tumor growth.

Results: Metformin, DCA, and oxamate effectively attenuated bortezomib-induced neuropathic pain without compromising the anticancer efficacy of bortezomib in both male and female mice. The LLC model exhibited a paraneoplastic neuropathy-like phenotype. Significant sex differences were observed, with male mice exhibiting larger tumors compared to females. Oxamate was more effective in alleviating allodynia in males, while metformin and DCA showed greater efficacy in reducing tumor growth in females.

Discussion: Targeting metabolic pathways can alleviate CIPN without interfering with bortezomib's anticancer effects. The LLC model may serve as a tool for studying paraneoplastic neuropathy. Sex differences in tumor growth and response to metabolic interventions highlight the importance of considering sex as a biological variable in preclinical and clinical studies investigating cancer biology, CIPN, and potential therapeutic interventions.