European journal of pain : EJP
-
In order to decide between avoiding pain or pursuing competing rewards, pain must be assigned an abstract value that can be traded against that of competing goods. To assess the relationship between subjectively perceived pain and its value, we conducted an experiment where participants had to accept or decline different intensities of painful electric shocks in exchange of monetary rewards. ⋯ This work provides a description of the pain value function indicating how much people are willing to pay to avoid different intensities of pain. We found that the function was curvilinear, suggesting that the same unit of subjective pain has more value in the high vs. low pain range. Moreover, the pain value was influenced by the experimental manipulation of the rewards distribution and of the inter-individual differences in harm avoidance and persistence. Altogether, the present study provides a detailed account of how subjectively experienced pain is assigned value.
-
Nerve injury can lead to ectopic activation of injured nociceptorsand central sensitization characterized by allodynia and hyperalgesia. Reduction in the activity of primary afferent neurons has been shown to be sufficient in alleviating peripherally generated pain. The cell bodies of such trigeminal nociceptors are located in the trigeminal ganglia (TG) with central processes that terminate in the brainstem trigeminal nucleus caudalis (TNC). The TG is therefore a strategic locus where afferent input can be manipulated. We hypothesized that chemogenetic inhibition of TG would suppress TNC neuronal activity and attenuate pain behaviour in a rat model of painful traumatic trigeminal neuropathy (PTTN). ⋯ Trigeminal neuropathic pain is highly resistant to therapy and we are in dire need of novel approaches. This study provides further evidence for the successful application of DREADDs as an effective tool for modulating central nervous system function. CNO mediated activation of hM4Di-DREADDs in the trigeminal ganglion (TG) attenuates nerve injury induced neuropathic pain by acting on hyperactive TG cells. It also establishes the TG as an effective target to manage pain in the face and head. Accessing the TG in clinical populations is a relatively simple and safe procedure, making this approach highly significant. Moreover, the methodology described here has applications in trigeminal neuropathic pain from traumatic other etiologies and in spinal neuropathic pain. Chronic pain syndromes are characterized by a progressive failure of brain centers to adequately inhibit pain and as these are identified, we may be able to target them for therapy. Therefore, our findings might have wide application in chronic pain syndromes.
-
We evaluated different pain profiles as prospective predictors of multisite pain in 13-year-old adolescents (1300 girls and 1457 boys) enrolled in Generation XXI, a birth cohort study in Portugal. ⋯ We identified sex-specific pain features that can be collected by practitioners in the first decade of life to improve the stratification of children in terms of their future risk of a maladaptive pain experience in adolescence. Using a prospective population-based cohort design, we show that early multisite pain and psychosocial triggers are relevant predictors of future multisite pain in girls, whereas repeated reports of high-frequency pain leading to activity restrictions are predictive of adolescent multisite pain in boys.
-
Observational Study
Perceived risk of opioid use disorder secondary to opioid analgesic medication use by the general population in France.
In Europe and France, the use of opioid analgesic drugs has become widespread as an option for pain management. However, their use can lead to nonmedical use and/or opioid use disorder (OUD). This work aimed to assess the perceived risk of OUD secondary to opioid analgesic drugs use by the general population. ⋯ This study found that the risk of OUD secondary to opioid analgesics use is well perceived in the general population, but that those having already used opioid analgesics expressed little concern for themselves. This finding could potentially help to raise awareness of healthcare providers and policy makers on the lack of perceived risk regarding these drugs and the need to inform and identify at-risk patients in primary care.
-
Complex regional pain syndrome (CRPS) is an orphan disease occurring as a complication after trauma. Due to its acute onset and the typical clinical presentation of the inflammatory and autonomous signs, it is an eye-catching chronic pain disease affecting also young and working people. In social media and the internet, high pain severity and the unfavourable prognosis are often empathized. ⋯ This study compares complex regional pain syndrome (CRPS) and chronic musculoskeletal pain and questions previously reported pain, disability and lifestyle factors associated with CRPS.