Pain
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Older adults are largely under-represented in low back pain (LBP) research. In light of the ageing population, it is crucial to understand the influence of comorbidities and lifestyle factors on the risk and prognosis of LBP in older adults. The aims of this study were to describe the course of LBP in older men; to investigate whether comorbidities/lifestyle factors can predict the course of LBP in older men; to assess if comorbidities/lifestyle factors increase the risk of developing LBP in older men. ⋯ The odds of persistent pain at 24 months increased with each additional alcoholic drink/wk (odds ratio [OR] = 1.10, 95% confidence interval [CI]: 1.01-1.22; P = 0.03) and each additional unit of body mass index (OR = 1.28, 95% CI: 1.04-1.60; P = 0.02), but reduced for men who speak English at home (OR = 0.58, 95% CI: 0.35-0.96; P = 0.03). In older men, free of LBP at baseline (n = 673), for every additional comorbidity there was an increased risk of developing LBP (OR = 1.17, 95% CI: 1.00-1.37; P = 0.05). These results demonstrate the influence of lifestyle factors and comorbidities on LBP in older men and suggest that the consideration of these issues in management may improve outcomes.
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Migraine pathophysiology includes altered brainstem excitability, and recent neuromodulatory approaches aimed at controlling migraine episodes have targeted key brainstem relay and modulatory nuclei. In this study, we evaluated the impact of respiratory-gated auricular vagal afferent nerve stimulation (RAVANS), a novel neuromodulatory intervention based on an existing transcutaneous vagus nerve stimulation approach, in the modulation of brainstem activity and connectivity in migraine patients. We applied 3T-functional magnetic resonance imaging with improved in-plane spatial resolution (2.62 × 2.62 mm) in episodic migraine (interictal) and age- and sex-matched healthy controls to evaluate brain response to RAVANS (gated to either inhalation or exhalation) and sham stimulation. ⋯ Increased connectivity was inversely correlated with relative time to the next migraine attack, suggesting clinical relevance to this change in connectivity. Poststimulation effects were also noted immediately after eRAVANS, as we found increased activation in putative pontine serotonergic (ie, nucleus raphe centralis) and noradrenergic (ie, locus coeruleus) nuclei in response to trigeminal sensory afference. Regulation of activity and connectivity of brainstem and cortical regions involved in serotonergic and noradrenergic regulation and pain modulation may constitute an underlying mechanism supporting beneficial clinical outcomes for eRAVANS applied for episodic migraine.
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To evaluate changes in DNA methylation profiles in patients with fibromyalgia (FM) compared to matched healthy controls (HCs). All individuals underwent full clinical and neurophysiological assessment by cortical excitability (CE) parameters measured by transcranial magnetic stimulation. DNA from the peripheral blood of patients with FM (n = 24) and HC (n = 24) were assessed using the Illumina-HumanMethylation450 BeadChips. ⋯ Fibromyalgia has a hypomethylation DNA pattern, which is enriched in genes implicated in stress response and DNA repair/free radical clearance. These changes occurred parallel to changes in CE parameters. New epigenetic insights into the pathophysiology of FM may provide the basis for the development of biomarkers of this disorder.
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Pain is a frequent but still neglected nonmotor symptom of Parkinson disease (PD). However, neural mechanisms underlying pain in PD are poorly understood. Here, we explored whether the high prevalence of pain in PD might be related to dysfunctional descending pain control. ⋯ Interestingly, dACC-DLPFC connectivity during pain anticipation was negatively associated with midcingulate cortex activity during the receipt of pain in PD patients. This study indicates altered neural processing during the anticipation and receipt of experimental pain in drug-naive PD patients. It provides first evidence for a progressive decline in descending pain modulation in PD, which might be related to the high prevalence of pain in later stages of PD.
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There is evidence to suggest a role of emotions in placebo and nocebo effects, but whether acute psychological stress changes the magnitude of placebo or nocebo responses has not been tested. In a clinically relevant model of visceroception, we assessed effects of acute psychological stress on changes in urgency and pain in response to positive or negative treatment suggestions. In 120 healthy volunteers, perceived urge-to-defecate and pain in response to individually calibrated rectal distensions were measured with visual analogue scales during a BASELINE. ⋯ For pain, effects of stress emerged for nocebo responses, which were only evident in stressed groups (P = 0.009). This is the first experimental study supporting effects of acute psychological stress on placebo and nocebo responses in visceroception. Results call for mechanistic as well as patient studies to assess how psychological stress shapes patients' treatment expectations and thereby affects health outcomes.