Pain
-
Little is known about the contribution of placebo effects and changes observed with no treatment in interventions for nonspecific low back pain (NSLBP). This systematic review assessed the proportions of the overall treatment effect that may be attributable to specific treatment effects, placebo effects, and changes observed with no treatment in randomized controlled trials (RCTs) in patients with NSLBP. Trials published before 2019 were identified from a published systematic review, and the search was updated in MEDLINE, Embase, and Cochrane Central for trials published between January 2019 and March 2023. ⋯ For physical function (11 studies) and HRQoL (6 studies), these proportions were 34%, 13%, and 53%, and 11%, 41%, and 48%, respectively. These results show that approximately half of the overall treatment effect of conservative and mainly passive interventions for patients with chronic NSLBP is attributable to changes observed with no treatment, rather than specific or placebo effects of treatments. However, the certainty of evidence was very low to low, suggesting that the true effects might be markedly different from the effect sizes underlying these estimates.
-
Neuropathic pain is a devastating condition where current therapeutics offer little to no pain relief. Novel nonnarcotic therapeutic targets are needed to address this growing medical problem. Our work identified the G-protein-coupled receptor 160 (GPR160) as a potential target for therapeutic intervention. ⋯ Cocaine- and amphetamine-regulated transcript peptide plays a role in various affective behaviors, such as anxiety, depression, and cognition. There are no differences in learning, memory, and anxiety between Gpr160 KO mice and their age-matched and sex-matched control floxed mice. Results from these studies support the pronociceptive roles of CARTp/GPR160 and GPR160 as a potential therapeutic target for treatment of neuropathic pain.
-
Growing evidence has suggested that time-varying functional connectivity between different brain regions might underlie the dynamic experience of pain. This study used a novel, data-driven framework to characterize the dynamic interactions of large-scale brain networks during sustained pain by estimating recurrent patterns of phase-synchronization. Resting-state functional magnetic resonance imaging signals were collected from 50 healthy participants before (once) and after (twice) the onset of sustained pain that was induced by topical application of capsaicin cream. ⋯ These changes can account for the perceived pain intensity and reported unpleasantness induced by capsaicin application. In contrast, state 3, characterized by phase-synchronization between the cognitive control network and sensory networks, decreased after the onset of sustained pain. These results are indicative of a shift toward internally directed self-referential processes (state 1) and away from externally directed cognitive control processes (state 3) during sustained pain.
-
Despite growing global concern over opioids, little is known about the epidemiology of opioid use in children and adolescents. This retrospective study investigated opioid use trends and identified risk factors associated with sustained opioid use among outpatient children and adolescents in Israel. Electronic health records of 110,955 children and adolescents were used to establish opioid purchase trends in outpatient settings between 2003 and 2021. ⋯ Risk factors with significant adjusted hazard ratios for sustained use included history of frequent doctor visits 1.82 (95% CI [1.50-2.22]) and drug purchases 1.30 (95% CI [1.07-1.58]), malignancy 1.50 (95% CI [1.07-2.09]), history of cardiovascular (1.44 (95% CI [1.04-1.98]) and pain-related conditions 1.34 (95% CI [1.14-1.58]), and different opioid substances (relative to codeine use): tramadol 2.38 (95% CI [1.73-3.27]), oxycodone 4.29 (95% CI [3.00-6.16]), and "other strong opioids" 6.05 (95% CI [3.59-10.2]). Awareness of observed increase in opioid purchases is crucial for doctors and public health practitioners. Additional monitoring and secondary prevention of children and adolescents possessing the identified risk factors should facilitate where appropriate reducing sustained opioid use when it is unnecessary.