Pain
-
Data are equivocal on the consequences of COVID-19 pandemic on pain and well-being for individuals with chronic pain. Furthermore, little is known regarding its impact on the health of young adults with chronic pain. We conducted a longitudinal study to compare pain, psychological functioning, and substance use before and during the pandemic of 196 young adults with chronic pain. ⋯ Mixed linear models revealed that COVID-19 exposure and impact were not associated with changes in pain intensity or interference, with female sex associated with increased pain intensity (β = 0.86, P = 0.02) and pain interference (β = 0.87, P = 0.02). Our findings indicated relative stability of pain symptoms experienced by young adults with chronic pain. However, the increases in anxiety highlight the need to facilitate treatment access for mental health services to mitigate downstream impact.
-
Resistance training-based exercise is commonly prescribed in the clinic for the treatment of chronic pain. Mechanisms of aerobic exercise for analgesia are frequently studied, while little is known regarding resistance training mechanisms. We developed a resistance training model in mice and hypothesized resistance training would protect against development of muscle pain, mediated through the activation of androgen receptors. ⋯ However, single administration of flutamide (1, 3, 10 mg/kg) in resistance-trained animals had no effect on existing exercise-induced protection against muscle pain. Therefore, resistance training acutely increases lactate and testosterone and strength overtime. Eight weeks of resistance training prevents the development of hyperalgesia through the activation of androgen receptors in an animal model of muscle pain.
-
In this case report, we used virtual reality (VR) to explore pain evoked by only the appearance of being touched (rather than actually being touched) in a person with complex regional pain syndrome type II. Furthermore, we explored the degree to which this visually evoked pain could be extinguished by applying exposure principles in VR. In stage 1, we identified 4 specific scenarios where pain was triggered by visually simulated touch (without physical stimulation) and used these scenarios to quantify baseline sensitivity to visuotactile stimulation. ⋯ This case report describes the phenomena of visually evoked pain. Moreover, it describes the near complete extinguishing of visually evoked pain through virtual graded exposure. How improvements gained in VR might be better transferred to real-word improvements merits further investigation.
-
Randomized Controlled Trial
Non-invasive vagus nerve stimulation modulates trigeminal but not somatosensory perception: functional evidence for a trigemino-vagal system in humans.
Noninvasive vagus nerve stimulation (nVNS) is effective in several types of headache disorders. We sought to unravel the mechanism of how nVNS exhibits this efficacy. This study used a randomized, single-blind, sham-controlled, crossover design and comprised 3 projects with 3 independent cohorts of healthy participants. ⋯ Heart rate variability parameters did not change after nVNS. Our results provide functional evidence of a long hypothesized functional trigemino-vagal system in humans and may explain why nVNS is effective in some headache disorders but not in somatic pain disorders. Because unilateral nVNS modulated the trigeminal thresholds bilaterally, this effect is probably indirect through a central top-down mechanism.
-
We assessed the joint effects of back pain and mental health conditions on healthcare utilization and costs in a population-based sample of adults in Ontario. We included Ontario adult respondents of the Canadian Community Health Survey between 2003 and 2012, followed up to 2018 by linking survey data to administrative databases. Joint exposures were self-reported back pain and mental health conditions (fair/poor mental health, mood, and anxiety disorder). ⋯ There was no evidence of synergism for all-cause utilization or costs. Combined effects of back pain and mental health conditions on back pain-specific utilization or opioid prescription were greater than expected, with evidence of synergism. Health services targeting back pain and mental health conditions together may provide greater improvements in outcomes.