Pain
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There is evidence of greater opioid prescription to individuals in the United States with mental health conditions. Whether these associations generalize beyond the US prescription environment and to familial mental health and socioeconomic status (SES) has not been examined comprehensively. This study estimated associations of diverse preexisting mental health diagnoses, parental mental health history, and SES in childhood with opioid analgesic prescription patterns nationwide in Sweden. ⋯ All mental health conditions were associated with greater LTOT rates (hazard ratios from 1.66 [1.56-1.77] for bipolar disorder to 3.82 [3.51-4.15] for opioid use disorder) and were similarly associated with concurrent benzodiazepine-opioid therapy. Among 1,482,462 adolescents and young adults, initiation and LTOT rates were greater for those with parental mental health history or lower childhood SES. Efforts to understand and ameliorate potential adverse effects of opioid analgesics must account for these patterns.
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Spinal hyperexcitability is a key event in the development of persistent pain, and arises partly from alterations in the number and localization of α-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA)-type glutamate receptors. However, determining precisely where these changes occur is challenging due to the requirement for multiplex labelling and nanoscale resolution. The recent development of super-resolution light microscopy provides new tools to address these challenges. ⋯ Direct stochastic optical reconstruction microscopy revealed a 59% increase in total GluA1 immunolabelling in the SCDH in the carrageenan group, which was not detected by confocal microscopy. Cell type-specific analyses identified a 10-fold increase in GluA1 localized to SP structures, and identified GluA1 nanodomains that scaled with behavioural hypersensitivity, and were associated with synaptic release sites. These findings demonstrate that dSTORM has the sensitivity and power to detect nanoscale anatomical changes in the SCDH, and provides new evidence for synaptic insertion of GluA1-AMPA-Rs at spinal peptidergic nociceptive terminals in a model of inflammatory pain.
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Opioids are widely prescribed for chronic pain, including neuropathic pain, despite growing evidence of long-term harm. Previous preclinical studies have documented exacerbation of nociceptive hypersensitivity, including that induced by peripheral nerve injury, by morphine. The present series of behavioral studies sought to replicate and extend our prior research, which demonstrated a multimonth exacerbation of nociceptive hypersensitivity by a 5-day course of morphine initiated 10 days after nerve injury. ⋯ Furthermore, enduring exacerbation of nociceptive hypersensitivity is also observed when the same dosing regimen for either morphine, fentanyl, or oxycodone begins 1 month after nerve injury. Finally, a striking result from these studies is that no such exacerbation of nociceptive hypersensitivity occurs when either morphine, fentanyl, or oxycodone dosing begins at the time of nerve injury. These results extend our previous findings that morphine exacerbates nociceptive hypersensitivity to the clinically relevant opioids fentanyl and oxycodone when administered after the development of nociceptive hypersensitivity, while also providing possible clinically relevant insight into when these opioids can be safely administered and not exacerbate neuropathic pain.
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Randomized Controlled Trial
A randomized controlled efficacy trial of Mindfulness-Based Stress Reduction compared to an active control group and usual care for fibromyalgia: the EUDAIMON study.
Fibromyalgia (FM) syndrome represents a great challenge for clinicians and researchers because the efficacy of currently available treatments is limited. This study examined the efficacy of mindfulness-based stress reduction (MBSR) for reducing functional impairment as well as the role of mindfulness-related constructs as mediators of treatment outcomes for people with FM. Two hundred twenty-five participants with FM were randomized into 3 study arms: MBSR plus treatment-as-usual (TAU), FibroQoL (multicomponent intervention for FM) plus TAU, and TAU alone. ⋯ An unreliable number needed to treat value of 9 (not computable 95% CI) was found for FibroQoL vs TAU. Changes produced by MBSR in functional impact were mediated by psychological inflexibility and the mindfulness facet acting with awareness. These findings are discussed in relation to previous studies of psychological treatments for FM.