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S100B single nucleotide polymorphisms exhibit sex-specific associations with chronic pain in sickle cell disease in a largely African-American cohort.

Pain in sickle cell disease (SCD) is severe and multifaceted resulting in significant differences in its frequency and intensity among individuals. In this study, we examined the influence of S100B gene single nucleotide polymorphisms (SNP) on acute and chronic pain variability in SCD.

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The evaluating prescription opioid changes in veterans (EPOCH) study: Design, survey response, and baseline characteristics.

In the United States (US), long-term opioid therapy has been commonly prescribed for chronic pain. Since recognition of the opioid overdose epidemic, clinical practice guidelines have recommended tapering long-term opioids to reduced doses or discontinuation. The Effects of Prescription Opioid Changes for veterans (EPOCH) study is a national population-based prospective observational study of US Veterans Health Administration primary care patients designed to assess effects of evolving opioid prescribing practice on patients treated with long-term opioids for chronic pain. A stratified random sampling design was used to identify a survey sample from the target population of patients treated with opioid analgesics for ≥ 6 months. Demographic, diagnostic, visit, and pharmacy dispensing data were extracted from existing datasets. A 2016 mixed-mode mail and telephone survey collected patient-reported data, including the main patient-reported outcomes of pain-related function (Brief Pain Inventory interference; BPI-I scores 0-10, higher scores = worse) and health-related quality of life. Data on survey participants and non-participants were analyzed to assess potential nonresponse bias. Weights were used to account for design. Linear regression models were used to assess cross-sectional associations of opioid treatment with patient-reported measures. Of 14,160 patients contacted, 9253 (65.4%) completed the survey. Participants were older than non-participants (63.9 ± 10.6 vs. 59.6 ± 13.0 years). The mean number of bothersome pain locations was 6.8 (SE 0.04). Effectiveness of pain treatment and quality of pain care were rated fair or poor by 56.1% and 45.3%, respectively. The opioid daily dosage range was 1.6 to 1038.2 mg, with mean = 50.6 mg (SE 1.1) and median = 30.9 mg (IQR 40.7). Among the 73.2% of patients who did not receive long-acting opioids, the mean daily dosage was 30.4 mg (SE 0.6) and mean BPI-I was 6.4 (SE 00.4). Among patients who received long-acting opioids, the mean daily dosage was 106.2 mg (SE 2.8) and mean BPI-I was 6.8 (SE 0.07). Higher daily dosage was associated with worse pain-related function and quality of life among patients without long-acting opioids, but not among patients with long-acting opioids. Future analyses will use follow-up data to examine effects of opioid dose reduction and discontinuation on patient outcomes.

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Prognostic indicators for poor outcomes in low back pain patients consulted in primary care.

Non-specific low back pain (NSLBP) is the most prevalent musculoskeletal condition in western countries and is associated with persistent disability and high consumption of health care resources. NSLBP patients first seek primary health care services but the outcomes are often uncertain. This study aimed to examine the clinical course of the outcomes and to identify prognostic indicators for poor outcomes in NSLBP patients who consulted primary care.

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Subcortical structural abnormalities in female neuromyelitis optica patients with neuropathic pain.

Neuromyelitis optica (NMO) is a disease characterised by severe relapses of optic neuritis and longitudinally extensive transverse myelitis and it has a strong female predilection. Pain is one of the most typical symptom in NMO. However, few studies have been conducted to examine the neuropathic pain mechanism of NMO patients or gender-specific effects using magnetic resonance imaging technique. A total of 38 female patients with NMO, 28 with pain (NMOWP) and 10 without pain (NMOWoP), were classified using the Brief Pain Inventory (BPI); 22 healthy females were also recruited. We used the FSL Image Registration and Segmentation Toolbox (FIRST) for subcortical region volumes quantifications, and voxel-based morphometry analysis for cortical gray matter (GM) volume, to examine the brain morphology in NMOWP patients. In addition, correlation test between structural measurements of NMO patients and clinical indexes was also performed. The results showed: 1) no significant differences in cortical GM density between the NMOWP and NMOWoP groups; 2) significantly smaller hippocampus and pallidum volumes in the NMOWP group compared with the NMOWoP group; 3) significant negative correlation between the average BPI and volumes of the accumbens nucleus and thalamus in NMO patients. These results revealed that structural abnormality exists in NMO female patients who have pain, with significant implications for our understanding of the brain morphology in NMO patients with pain.

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Heightened Risk for Pain in Young Adult Women with a History of Childhood Maltreatment: A Prospective Longitudinal Study.

A child maltreatment history is reported more frequently among adults with chronic pain compared to the general population; unfortunately, studies have primarily relied upon retrospective maltreatment reports by adults with chronic pain. This prospective study assessed pain symptoms in a cohort of young adult women with a documented history of child maltreatment, compared with a matched cohort of women who did not experience childhood maltreatment. Young women (N = 477) were recruited between ages 14-17 years and followed annually to age 19. Of these women, 57% experienced maltreatment (i.e., physical, sexual, or emotional abuse, neglect; n = 273) substantiated by child welfare record. Maltreated women were demographically-matched to non-maltreated women, also confirmed by child welfare record. In adolescence, post-traumatic stress was assessed. Women were contacted as young adults (Mage = 24.76; n = 383) and surveyed about their pain experiences, including the presence of pain in the past week, pain severity (0-10), and number of body areas with pain. Mediation path analyses examining the impact of maltreatment and adolescent post-traumatic stress on young adult pain were estimated via structural equation modeling. As adults, women who had experienced child maltreatment reported higher pain intensity, a greater number of pain locations, and were more likely to experience pain in the previous week than non-maltreated women. Adolescent post-traumatic stress partially explained the effects of maltreatment on pain. Young adult women who experienced child maltreatment are at higher risk for pain, particularly when they also experienced post-traumatic stress as adolescents.

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Are there really only two kinds of people in the world? Evaluating the distribution of change from baseline in pain clinical trials.

It is often assumed that there are two types of pain patients: those who respond well to efficacious pain therapies and those who do not respond at all, with few people in the middle. This assumption is based on research that claims that changes in pain intensity have a bimodal distribution. The claim of bimodality has led to calls for a change in how pain clinical trials are designed and analyzed, for example, performing "responder" analyses instead of comparing group means to evaluate the treatment effect. We analyzed data from four clinical trials, two each of duloxetine and pregabalin, for chronic musculoskeletal and neuropathic pain conditions to critically examine the claim of bimodality of the distribution of change in pain intensity. We found that the improper construction of histograms, using unequal bin widths, was the principal flaw leading to the bimodality claim, along with the use of the oft-criticized baseline observation carried forward (BOCF) method for imputing missing data also serving as a contributing factor. Properly constructed histograms of absolute change in pain intensity using equal bin widths, combined with more principled methods for handling missing data, resulted in distributions that had a more unimodal appearance. While our findings neither support nor refute the hypothesis that distinct populations of "responders" and "non-responders" to pain interventions exist, the analyses presented in earlier work do not provide support for this hypothesis, nor for the recommendation that pain clinical trials prioritize "responder" analyses, a less efficient analysis strategy.

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Characterization of cowhage-induced pruritus in inflamed and non-inflamed skin.

Pruritus is a major symptom of many inflammatory diseases and impacts greatly the quality of life in patients. We aimed to specify the characteristics of experimentally induced pruritus in normal skin and in experimentally induced inflammatory dermatitis in healthy volunteers.

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Inflammation is associated with pro-nociceptive brain connections in rheumatoid arthritis patients with concomitant fibromyalgia.

Rheumatoid arthritis (RA) patients with comorbid fibromyalgia (FM) manifest alterations in brain connectivity synonymous with central sensitization. Here we consider how peripheral inflammation, the principal nociceptive stimulus in RA, interacts with brain connectivity in RA patients with comorbid FM.

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Hypnosis Program Effectiveness in a 12-week Home Care Intervention To Manage Chronic Pain in Elderly Women.

While the prevalence of pain increases with age, too much medication can lead to negative side effects. Complementary approaches, such as clinical hypnosis, could be relevant in pain management. While evidence in the literature has shown that clinical hypnosis is effective in child and adult populations, there have been few studies in aging populations. Furthermore, the feasibility and effectiveness of clinical hypnosis in preventive home care in elderly populations with pain have never been established. The goal of this within-subject study was to determine the feasibility and the effects of three 15-min hypnosis sessions delivered during home care interventions over a 12-week period in 15 elderly women with chronic pain (mean age, 81 years; range, 65-87 years).

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Clinicians’ Initial Experiences of Transition to Online Interdisciplinary Pain Rehabilitation During the Covid-19 Pandemic.

Public health legislation during the CO-VID-19 pandemic has resulted in forced transitioning to the use of remote care in order to continue the provision of pain rehabilitation worldwide. The objective of this study was to gain insight into clinicians' initial experiences with the provision of interdisciplinary pain rehabilitation via videoconferencing.

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