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Repetitive transcranial magnetic stimulation treatment of major depressive disorder and comorbid chronic pain: response rates and neurophysiologic biomarkers.

Major depressive disorder (MDD) and chronic pain are highly comorbid, and pain symptoms are associated with a poorer response to antidepressant medication treatment. It is unclear whether comorbid pain also is associated with a poorer response to treatment with repetitive transcranial magnetic stimulation (rTMS).

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Thalamic Deep Brain Stimulation for Post-Traumatic Neuropathic Limb Pain: Efficacy at Five Years’ Follow-Up and Effective Volume of Activated Brain Tissue.

Chronic neuropathic pain affects 7%-10% of the population. Deep brain stimulation (DBS) has shown variable but promising results in its treatment. This study prospectively assessed the long-term effectiveness of DBS in a series of patients with chronic neuropathic pain, correlating clinical results with neuroimaging. Sixteen patients received 5 years' post-surgical follow-up in a single center. Six had phantom limb pain after amputation and 10 had deafferentation pain after traumatic brachial plexus injury. Patient-reported outcome measures were completed before and after surgery, using VAS, UWNPS, BPI and SF-36 scores. Neuroimaging evaluated electrode location and effective volumes of activated tissue (VAT). Two subgroups were created based on the percentage of VAT superimposed upon the ventroposterolateral thalamic nucleus (eVAT), and clinical outcomes were compared. Analgesic effect was assessed at 5 years and compared to preoperative pain, with an improvement on VAS of 76.4% (p = 0.0001), on UW-NPS of 35.2% (p = 0.3582), on BPI of 65.1% (p = 0.0505) and on SF-36 of 5% (p = 0.7406). Eight patients with higher eVAT showed improvement on VAS of 67.5% (p=0.0017) while the remaining patients, with lower eVAT, improved by 50.6% (p=0.03607). DBS remained effective in improving chronic neuropathic pain after 5 years. While VPL-targeting contributes to success, analgesia is also obtained by stimulating surrounding posterior ventrobasal thalamic structures and related spinothalamocortical tracts.

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Synergistic effect of chronic pain and nonsuicidal self-harm on pain sensitivity.

Abnormalities in pain processing have been observed in patients with chronic pain conditions and in individuals who engage in self-harm, specifically nonsuicidal self-injurious behaviors (NSSI). Both increased and decreased pain sensitivity have been described in chronic pain patients, while decreased pain sensitivity is consistently observed in individuals with NSSI. The objective of the study was to identify the differential effects of chronic pain and NSSI on experimental pain sensitivity, specifically pressure pain threshold, in depressed patients. Moreover, the role that hopelessness may play between depression severity and pain sensitivity was also examined. Depressed patients with and without chronic pain, and with and without lifetime self-harm behaviors were analyzed into four groups. Group 1 (N = 42) included depressed patients with both Chronic pain ( +) and Self-harm ( +), Group 2 (N = 53) included depressed patients with Chronic pain ( +) but no Self-harm (-), Group 3 (N = 64) included depressed patients without Chronic pain (-), but Self-harm ( +), and Group 4 (N = 81) included depressed patients with neither Chronic pain (-) nor Self-harm (-). Healthy controls (N = 45) were also recruited from the community. Depressed patients with both Chronic pain ( +) and Self-harm ( +) reported higher pressure pain threshold measures when compared with the other groups. Mediation analysis indicated that hopelessness mediates the relationship between depression severity and pressure pain threshold. Our findings suggest that a multiprong approach including adequate mental health services and pain control for depressed patients with comorbid chronic pain and nonsuicidal self-harm is needed to yield effective outcomes.

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Erenumab treatment for migraine prevention in Japanese patients: Efficacy and safety results from a Phase 3, randomized, double-blind, placebo-controlled study.

Erenumab is a human anti-calcitonin gene-related peptide receptor monoclonal antibody approved for migraine prevention. Global studies have demonstrated its efficacy in chronic and episodic migraine (EM). Here we report the outcomes from a Phase 3 study of erenumab in Japanese patients with chronic migraine (CM) or EM.

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The role of the observers’ perception of a model’s self-confidence in observationally induced placebo analgesia.

The aim of this study was to investigate the effect on observationally acquired placebo analgesia of a model's self-confidence as well as the observer's self-esteem and self-efficacy. In addition, we aimed to verify the stability of the placebo effect induced by observational learning. Participants (N = 60) were randomly assigned to one of three groups: a self-confident model, an unself-confident model, and a control group. In the experimental groups, participants watched a videotaped model who rated the intensity of electrocutaneous pain stimuli applied in the placebo condition as lower than those applied in the non-placebo condition. The different levels of self-confidence in these groups were manifested in the body posture and facial expressions of the model as well as in specific behavior that accompanied the assessment of pain. Then, 16 electrocutaneous pain stimuli of the same intensity, preceded by the placebo or non-placebo, were applied to participants. In both experimental groups, in contrast to the control group, participants experienced less pain in the placebo than in the non-placebo condition. Although the magnitude of placebo analgesia did not differ between the experimental groups, multiple regression analysis revealed that the perceived self-confidence of the model, but not the self-efficacy or self-esteem of the observer, was a significant predictor of the placebo effect. Moreover, placebo analgesia induced by observational learning did not extinguish over the course of the experiment. These results support the premise that the observers' perception of a model's self-confidence plays a significant role in placebo effects. PERSPECTIVE: The results of this study open the discussion on the role of model's features in the effectiveness of observational learning in the induction of placebo effects. The study provides the very first suggestion that the perceived self-confidence of the model may be related to the magnitude of the observationally induced placebo analgesia. It suggests that self-confidence of other patients and medical staff might affect individual pain experiences.

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Effects of the ABCB1 c.3435C>T (rs1045642) Polymorphism on Heat Pain Perception in Opioid-Free Adults With Chronic Pain.

The adenosine triphosphate-binding cassette, subfamily B, member 1 gene (ABCB1) encodes P-glycoprotein (P-gp) that influences the intracellular transport of solutes including endogenous opioid peptides. The primary objective of this study was to determine the effects of the ABCB1 polymorphism c.3435C>T (rs10454642) on heat pain (HP) perception in a group of opioid-free adults with chronic pain.

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Theta-burst versus 20 Hz repetitive transcranial magnetic stimulation in neuropathic pain: A head-to-head comparison.

High-frequency repetitive transcranial magnetic stimulation (rTMS) has been shown to reduce neuropathic pain, but intermittent "theta-burst" stimulation (iTBS) could be a better alternative because of shorter duration and greater ability to induce cortical plasticity. Here we compared head-to-head the pain-relieving efficacy of the two modalities when applied daily for 5 days to patients with neuropathic pain.

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A brief diagnostic screen for cluster headache: Creation and initial validation of the Erwin Test for Cluster Headache.

To use 1) newly generated data, 2) existing evidence, and 3) expert opinion to create and validate a new cluster headache screening tool.

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If headache has any association with hypertension, it is negative. Evidence from a population-based study in Nepal.

Hypertension and headache disorders are major contributors to public ill health, linked by a long-standing but questionable belief that hypertension is a conspicuous cause of headache. In Nepal, where hypertension is common and often untreated, we assessed the substance of this belief, hypothesising that, should hypertension be a significant cause of headache, a clear positive association between these disorders would exist.

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CGRP release in an experimental human trigeminal pain model.

Migraine and trigemino-autonomic cephalalgia attacks are associated with an increase of α-calcitonin-gene related peptide levels in the ipsilateral jugular vein. It is however unknown whether trigeminal pain stimulation in healthy subjects without headache disorders also induces increase of calcitonin-gene related peptide levels.

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