Using stratified medicine to understand, diagnose, and treat neuropathic pain

Neuropathic pain (NeuP) is defined as pain arising from a lesion or disease of the somatosensory nervous system. NeuP is common, affecting approximately 6-8% of the general population and currently treatment is inadequate due to both poor drug efficacy and tolerability. Many different types of injury can cause neuropathic pain including genetic (e.g. SCN9A gain of function variants), metabolic (e.g. diabetic polyneuropathy), infective (e.g. HIV associated neuropathy, hepatitis), traumatic and toxic (e.g. chemotherapy induced neuropathy) causes. Such injurious events can impact on anatomically distinct regions of the somatosensory nervous system ranging from the terminals of nociceptive afferents (in small fiber neuropathy) to the thalamus (in post-stroke pain). Classification of neuropathic pain using etiology and location remains an important aspect of routine clinical practice; however, pain medicine is coming to the realization that we need more precision in this classification. The hope is that improved classification will lead to better understanding of risk, prognosis and optimal treatment of NeuP

Near-infrared optical imaging of nucleic acid nanocarriers in vivo.

International audienceNoninvasive, real-time optical imaging methods are well suited to follow the in vivo distribution of nucleic acid nanocarriers, their dissociation, and the resulting gene expression or inhibition. Indeed, most small animal imaging devices perform bioluminescence and fluorescence measurements without moving the animal, allowing a simple, rapid, and cost-effective method of investigation of several parameters at a time, in longitudinal experiments that can last for days or weeks.Here we help the reader in choosing adapted near-infrared (NIR) fluorophores or pairs of fluorophores for Förster resonance energy transfer assays, imaging of reporter genes, as well as nanocarriers for in vivo gene and siRNA delivery. In addition, we present the labeling methods of these macromolecules and of their payload and the protocols to detect them using bioluminescence and NIR fluorescence imaging in mice

The efficacy of attentional distraction and sensory monitoring in chronic pain patients:A meta-analysis

Attentional strategies, such as distraction and sensory monitoring, are often offered to reduce pain and pain-related distress. However, evidence for their efficacy in chronic pain patients is equivocal. We report a meta-analysis on the efficacy of distraction and sensory monitoring in chronic pain patients, and explore possible methodological and theoretical moderators. The scientific literature was searched for relevant articles, which were coded for methodological quality and several theoretical and methodological moderator variables. Only 10 articles fulfilled the search criteria. Eight studies allowed us to compare distraction with a control condition, two studies to compare sensory monitoring with a control condition, and four studies to compare the effect of distraction with the effect of sensory monitoring. Overall, results indicate that distraction did not differ from control in altering pain experience (k=8; Hedges’ g=0.10, ns) and distress (k=2; Hedges’ g=0.549). Sensory monitoring did also not alter pain experience (k=2; Hedges’ g=-.21, ns) and distress (k=1; Hedges’ g=-0.191, ns). We found no evidence to support the superiority of distraction or sensory monitoring in altering pain compared to control conditions. We offer guidance for future theory-driven research to investigate distraction and sensory monitoring in this largely unexplored field, albeit one replete with methodological difficulties

Ambiguity, multiple streams, and EU policy

The multiple streams framework draws insight from interactions between agency and institutions to explore the impact of context, time, and meaning on policy change and to assess the institutional and issue complexities permeating the European Union (EU) policy process. The authors specify the assumptions and structure of the framework and review studies that have adapted it to reflect more fully EU decision-making processes. The nature of policy entrepreneurship and policy windows are assessed to identify areas of improvement. Finally, the authors sketch out a research agenda that refines the logic of political manipulation which permeates the lens and the institutional complexity which frames the EU policy process

Attention to pain and fear of pain in patients with chronic pain

To investigate how acceptance of illness affects chronic pain in terms of attention towards pain and fearful thinking of pain. 62 participants (50 women) with chronic pain carried a palmtop computer for 2 weeks. Eight times each day auditory signals were delivered to cue participants to complete questions about their experience. Multilevel analyses indicated that on moments with more intense pain, more fearful thinking about pain, and less positive emotions, attention to pain was increased. Illness acceptance did not moderate the relation between pain intensity and attention to pain. Results further indicated that on moments with more intense pain, more negative emotions, and less positive emotions, fearful thinking about pain was increased. Of particular interest was the finding that the relationship between pain intensity and fearful thinking about pain was less strong for those high in acceptance. Pain captures attention and elicits fearful thinking about pain. Acceptance may be a useful avenue to lower negative thinking about pain, and to increase well-being in patients with chronic illnesses

Development and external validation of multivariable risk models to predict incident and resolved neuropathic pain:a DOLORisk Dundee study

Neuropathic pain is difficult to treat, and an understanding of the risk factors for its onset and resolution is warranted. This study aimed to develop and externally validate two clinical risk models to predict onset and resolution of chronic neuropathic pain. Participants of Generation Scotland: Scottish Family Health Study (GS; general Scottish population; n = 20,221) and Genetic of Diabetes Audit and Research in Tayside Scotland (GoDARTS; n = 5236) were sent a questionnaire on neuropathic pain and followed- -up 18 months later. Chronic neuropathic pain was defined using DN4 scores (≥ 3/7) and pain for 3 months or more. The models were developed in GS using logistic regression with backward elimination based on the Akaike information criterion. External validation was conducted in GoDARTS and assessed model discrimination (ROC and Precision-Recall curves), calibration and clinical utility (decision curve analysis [DCA]). Analysis revealed incidences of neuropathic pain onset (6.0% in GS [236/3903] and 10.7% in GoDARTS [61/571]) and resolution (42.6% in GS [230/540] and 23.7% in GoDARTS [56/236]). Psychosocial and lifestyle factors were included in both onset and resolved prediction models. In GoDARTS, these models showed adequate discrimination (ROC = 0.636 and 0.699), but there was evidence of miscalibration (Intercept = − 0.511 and − 0.424; slope = 0.623 and 0.999). The DCA indicated that the models would provide clinical benefit over a range of possible risk thresholds. To our knowledge, these are the first externally validated risk models for neuropathic pain. The findings are of interest to patients and clinicians in the community, who may take preventative or remedial measures. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00415-022-11478-0