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Association between depression, anxiety, chronic pain, or opioid use and tumor necrosis factor inhibitor persistence in inflammatory arthritis.

Depression, anxiety, and chronic pain are common comorbidities in patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), and ankylosing spondylitis (AS) and may substantially impact patient outcomes. We aimed to determine whether these comorbidities were associated with earlier TNF-inhibitor (TNFi) discontinuation.

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The increased iron deposition of the gray matter over the whole brain in chronic migraine: an exploratory quantitative susceptibility mapping study.

Prior studies identified iron deposition in deep brain nuclei and the periaqueductal gray matter region in chronic migraine (CM), and less is known about the cerebral iron deposition over the whole cerebral gray matter in CM. The aim of this case-control study is to investigate the cerebral iron deposition of gray matter in CM using an advanced quantitative susceptibility mapping.

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Simultaneous brain, brainstem and spinal cord pharmacological-fMRI reveals involvement of an endogenous opioid network in attentional analgesia.

Pain perception is decreased by shifting attentional focus away from a threatening event. This attentional analgesia engages parallel descending control pathways from anterior cingulate (ACC) to locus coeruleus, and ACC to periaqueductal grey (PAG) – rostral ventromedial medulla (RVM), indicating possible roles for noradrenergic or opioidergic neuromodulators. To determine which pathway modulates nociceptive activity in humans we used simultaneous whole brain-spinal cord pharmacological-fMRI (N=39) across three sessions. Noxious thermal forearm stimulation generated somatotopic-activation of dorsal horn (DH) whose activity correlated with pain report and mirrored attentional pain modulation. Activity in an adjacent cluster reported the interaction between task and noxious stimulus. Effective connectivity analysis revealed that ACC interacts with PAG and RVM to modulate spinal cord activity. Blocking endogenous opioids with Naltrexone impairs attentional analgesia and disrupts RVM-spinal and ACC-PAG connectivity. Noradrenergic augmentation with Reboxetine did not alter attentional analgesia. Cognitive pain modulation involves opioidergic ACC-PAG-RVM descending control which suppresses spinal nociceptive activity.

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Non-invasive vagus nerve stimulation modulates trigeminal but not somatosensory perception: functional evidence for a trigemino-vagal system in humans.

Non-invasive vagus nerve stimulation (nVNS) is effective in several types of headache disorders. We sought to unravel the mechanism of how nVNS exhibits this efficacy. This study used a randomized, single-blind, sham-controlled, crossover-design, and comprised three projects with three independent cohorts of healthy participants. Project I (n=15) was explorative. Six quantitative sensory test (QST) parameters, including mechanical pain threshold (MPT), were measured over the left V1 dermatome and forearm, and compared before and after unilateral nVNS. Projects II (n=20) and III (n=21) were online pre-registered . QST parameters were compared over the left (Project II) or bilateral V1 and V3 dermatomes (Project III), respectively, in addition to the left forearm as a control. A secondary analysis of heart rate variability (HRV) using a historical control group was used to control for systemic effects of nVNS. Verum-nVNS induced trigeminal-specific modulation of pain threshold (i.e., MPT) over the left V1 in Project I, left V1 and V3 in Project II, and bilateral V1 and V3 in Project III. Data pooled from Project II and III demonstrated greater increase of MPT in the V1 vs. V3 dermatome. There were no differences associated with sham-nVNS in any projects. HRV parameters did not change after nVNS. Our results provide functional evidence of a long hypothesized functional trigemino-vagal system in humans and may explain why nVNS is effective in some headache but not in somatic pain disorders. Since unilateral nVNS modulated the trigeminal thresholds bilaterally, this effect is probably indirect through a central top-down mechanism.

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How do placebo effects contribute to mindfulness-based analgesia? Probing acute pain effects and interactions using a randomized balanced placebo design.

Recent sham-controlled studies suggest placebo effects contribute to acute pain relief following mindfulness interventions. However, the specific effects of mindfulness processes and their interaction with placebo effects remain unclear. This study aimed to characterize the role of mindfulness and placebo processes underlying mindfulness-based pain attenuation. Both treatment (focused-attention mindfulness vs sham) and instruction ("told mindfulness" vs "told sham") were manipulated in a balanced placebo design. Changes in acute heat pain were evaluated in 153 healthy adults randomized to receive 6 x 20 minutes of one of the four treatment by instruction interventions or no treatment. Participants receiving any intervention demonstrated improved pain outcomes (unpleasantness, intensity and tolerance) relative to no treatment. The instruction manipulation increased expectation for pain relief in those told mindfulness relative to told sham, but there were no main effects or interactions of treatment or instruction on pain outcomes. However, irrespective of actual intervention received, the belief of receiving mindfulness predicted increased pain threshold and tolerance, with expectancy fully mediating the effect on pain tolerance. These findings suggest a lack of specific effects of mindfulness and instruction on acute pain. Nonetheless, participants' expectancies and beliefs about the treatment they received did predict pain relief. Together with the overall improvement following any intervention, these findings suggest that expectancy and belief may play a stronger role in attenuating acute pain in novices following brief mindfulness interventions than the actual mindfulness-specific processes or instructions delivered.

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Pruritus in the Pediatric Burn Population.

Post-burn pruritus is a significant issue that can have a devastating impact on patient quality of life. Despite its known negative impact, few studies have focused on the pediatric population. Thus, the aim of this study was to determine the incidence of pruritus among pediatric burn patients as well as identify its predictive factors and commonly used treatments, including the novel use of laser therapy. A retrospective analysis of all burn patients treated at our pediatric burn centre from 2009 to 2017 was conducted. The primary outcome measure was the presence or absence of pruritus at any point following the burn. One thousand seven hundred and eighty-three patients met the inclusion criteria for this study. The mean age at injury was 3.67 years (SD 4.02) and the mean burn TBSA was 3.48% (SD 4.81) with most burns resulting from scalds (66%). In total, 665 patients (37.3%) experienced pruritus. Following multivariable logistic regression, TBSA, age > 5 years, burns secondary to fire/flames, and burn depth, were identified as significant predictors of pruritus (p < 0.05). Pruritus was treated with diphenhydramine (85.0%), hydroxyzine (37.3%), and gabapentin (4.2%) as well as massage (45.7%), pressure garments (20.0%), and laser therapy (8.6%). This study addresses the knowledge gap in literature related to post-burn pruritus among pediatric patients and includes one of the largest patient cohorts published to date. Moreover, the results further contribute to our understanding of post-burn pruritus in children and may help us to predict which patients are most likely to be affected, so that treatment can be initiated as soon as possible.

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Clinical characteristics of geriatric patients with non-specific chronic low back pain.

A comprehensive analysis of clinical information in patients with chronic low back pain (CLBP) was performed to clarify the clinical characteristics of geriatric LBP from the perspective of body composition, spinal alignment, and blood findings related to senescence. We enrolled 203 patients with an average age of 79.0 years (77 men and 126 women), with non-specific CLBP as a single-center prospective cohort study, the patients were compared with age- and sex-matched controls without CLBP using a propensity score-matching. We performed laboratory analysis, radiographic evaluations for global spinal parameter and lumbar degeneration, and body composition analysis using whole-body dual-energy X-ray absorptiometry. We observed a higher red blood cell distribution width (RDW) (p < 0.001), which is an index of aging, as well as a lower vitamin D level (p = 0.002), skeletal muscle mass index (p = 0.045) and a higher fat mass (p = 0.007) in patients with CLBP. Moreover, patients with geriatric CLBP had significantly lower lumbar lordosis (p = 0.024), and higher sagittal vertical axis (p = 0.006) was correlated with lower extremity and trunk muscle mass (p < 0.001), independent of lumbar degeneration. Geriatric patients with CLBP have sarcopenic fat accumulation and spinal sagittal malalignment with senescent status, such as elevated RDW and hypovitaminosis D.

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Complementary and integrative medicine perspectives among veteran patients and VHA healthcare providers for the treatment of headache disorders: a qualitative study.

To evaluate veteran patient and provider perceptions and preferences on complementary and integrative medicine (CIM) for headache management.

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Gold micro-particles for knee osteoarthritis.

This exploratory study investigates if intra-articular injected gold microparticles in knee osteoarthritis (KOA) reduce immunomodulatory-based pain via proteomic changes in the synovial fluid (SF) and serum.

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Diagnosis, consultation, treatment, and impact of migraine in the US: Results of the OVERCOME (US) study.

The ObserVational survey of the Epidemiology, tReatment and Care of MigrainE (OVERCOME; United States) study is a multicohort, longitudinal web survey that assesses symptomatology, consulting, diagnosis, treatment, and impact of migraine in the United States.

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