Chronic Pain and Chronic Stress: Two Sides of the Same Coin?

A History of Pain Studies and Changing Attitudes to the Welfare of Crustaceans

Early discussions about possible pain in crustaceans often comprised speculation and anecdotes. Experiments to investigate pain took guidance from these early debates, and from studies on other taxa. Many experiments provided data that are consistent with the idea of pain. However, that does not mean that pain has been proved, but they open the possibility. With each study that is consistent with pain being felt, the probability increases, but we will probably never have conclusive proof. Some responses appear to be nociceptive reflexes; however, they at least indicate that the animal responds to stimuli such as tissue damage, heat, acid, alkaline, or electric shock. The data are said to be consistent with pain only if they cannot be explained by reflexes. These studies have encouraged various organisations to improve the welfare of crustaceans, e.g., PETA, Crustacean Compassion, RSPCA, British Veterinary Association, UFAW, and HSA. They also formed much of the evidence included in the highly influential review of sentience for the UK government that resulted in the inclusion of decapod crustaceans in the Animal Welfare (Sentience) Act 2022. This recognises that decapod crustaceans are sentient. By contrast, the New York Declaration recognises there is a possibility of sentience. Others have argued against the idea of pain in crustaceans. Nevertheless, the 2022 Act provided an impetus to groups that campaign for improved welfare. Some UK retailers now require improved slaughter techniques for the shrimp/prawn they sell, and electrical stunning is the preferred slaughter method.

Repetitive Transcranial Magnetic Stimulation: Is it an Effective Treatment for Cancer Pain?

Cancer is a major public health issue, with an estimated 20 million new cases and 9.7 million cancer-related deaths worldwide in 2022. Approximately 44.5% of patients experience cancer pain, significantly impacting their quality of life and causing physical and psychological burdens. Repetitive transcranial magnetic stimulation (rTMS), a non-invasive neuromodulation technique, shows potential in managing cancer pain. This review summarizes current research on rTMS for cancer pain, focusing on pain directly caused by tumors, pain from cancer treatments, postoperative pain, and cancer-related symptoms. Additionally, rTMS shows promise in improving cancer-related fatigue, anxiety, depression, and cognitive dysfunction, which can indirectly reduce cancer pain. The analgesic mechanisms of rTMS include inhibiting nociceptive signal transmission in the spinal cord, modulating hemodynamic changes in brain regions, and promoting endogenous opioid release. High-frequency stimulation of the primary motor cortex (M1) has shown significant analgesic effects, improving patients' emotional and cognitive functions and overall quality of life. rTMS has a favorable safety profile, with most studies reporting no severe adverse events. In conclusion, rTMS holds substantial potential for cancer pain management, offering a non-invasive and multifaceted therapeutic approach. Continued research and clinical application are expected to establish rTMS as an essential component of comprehensive cancer pain treatment strategies, significantly enhancing the overall well-being of patients with cancer.

Treating chronic stress and chronic pain by manipulating gut microbiota with diet: can we kill two birds with one stone?

Background: Chronic stress and chronic pain are closely linked by the capacity to exacerbate each other, sharing common roots in the brain and in the gut. The strict intersection between these two neurological diseases makes important to have a therapeutic strategy aimed at preventing both to maintain mental health in patients. Diet is an modifiable lifestyle factor associated with gut-brain axis diseases and there is growing interest in its use as adjuvant to main therapies. Several evidence attest the impact of specific diets or nutrients on chronic stress-related disorders and pain with a good degree of certainty. A daily adequate intake of foods containing micronutrients such as amino acids, minerals and vitamins, as well as the reduction in the consumption of processed food products can have a positive impact on microbiota and gut health. Many nutrients are endowed of prebiotic, anti-inflammatory, immunomodulatory and neuroprotective potential which make them useful tools helping the management of chronic stress and pain in patients. Dietary regimes, as intermittent fasting or caloric restriction, are promising, although further studies are needed to optimize protocols according to patient's medical history, age and sex. Moreover, by supporting gut microbiota health with diet is possible to attenuate comorbidities such as obesity, gastrointestinal dysfunction and mood disorders, thus reducing healthcare costs related to chronic stress or pain.Objective: This review summarize the most recent evidence on the microbiota-mediated beneficial effects of macro- and micronutrients, dietary-related factors, specific nutritional regimens and dietary intervention on these pathological conditions.

No More Evasion: Redefining Conflict Behaviour in Human-Horse Interactions

Euphemisms, anthropomorphisms, and equivocation are established characteristics of traditional equestrian language. 'Evasion', 'resistance', and 'disobedience' are common labels assigned to unwelcome equine behaviours, implying that the horse is at fault for not complying with the human's cues and expectations. These terms appear to overlook multiple motivations that may directly result in the horse offering unwelcome responses, which may then inadvertently be reinforced. This article revisits some of the anthropocentric inferences in these terms and explores the harmful consequences of such convenient but incorrect labels before proposing a redefinition of 'conflict behaviour' in human-horse interactions: Responses reflective of competing motivations for the horse that may exist on a continuum from subtle to overt, with frequencies that range from a singular momentary behavioural response to repetitive displays when motivational conflict is prolonged. Addressing how inadequate terms may mask pain, obscure the horse's motivation, and deflect human culpability, this commentary highlights the merits of a multidisciplinary approach to terminology across equine research. Acknowledging that variables contributing to behaviour can be biological, environmental and anthropogenic, it emphasises the need for more investigation into the relationships between equicentric motivations reflecting equine telos and problematic horse behaviours.

The effects of lowering barometric pressure on pain behavior and the stress hormone in mice with neuropathic pain

BACKGROUND

Lowering barometric pressure (LP) can exacerbate neuropathic pain. However, animal studies in this field are limited to a few conditions. Furthermore, although sympathetic involvement has been reported as a possible mechanism, whether the sympathetic nervous system is involved in the hypothalamic-pituitary-adrenal (HPA) axis remains unknown. To address these issues, we investigated LP-induced hyperalgesia by focusing on the cumulative effect of LP and measuring plasma corticosterone levels as a marker of HPA axis activation in mice.

METHODS

Mice with chronic constriction injury (CCI) were used in this study. For behavioral tests, two types of LP stimulation were adopted: a single LP at 20 hPa (Single LP) and three consecutive LPs at 20 hPa (3LPs). Twelve mice were used for each protocol. The no-pressure-change protocol was used as the control. The mechanical sensitivity was tested before and after LP stimulation using von Frey filaments (vF). For corticosterone measurements, six CCI and six intact mice were exposed to 3LPs (CCI-3LPs and INT-3LPs), and another six CCI and six intact mice were exposed to the no-pressure-change protocol (CCI-NP and INT-NP). Blood samples were collected immediately after exposure. Plasma corticosterone levels were measured by ELISA.

RESULTS

The number of paw elevations by vF before and after LP stimulation did not differ significantly in either the Single LP or the no-pressure-change protocol. For the 3LPs, the number of paw elevations after LP stimulation was significantly greater than before stimulation. Plasma corticosterone levels in the CCI-3LPs were significantly higher than those in CCI-NPs. In intact mice, there was no significant difference in plasma corticosterone levels between the INT-3LPs and INT-NPs.

CONCLUSIONS

LP has a cumulative effect on neuropathic pain. Hypothalamic-pituitary-adrenal axis activation may have an important relationship with LP-induced pain in mice.

Momentary physical activity, subjective age, and the moderating role of pain

Subjective age, that is felt age compared to chronological age, is an important predictor of health and well-being in later life. It can fluctuate from day to day and from one moment to another. Previous cross-sectional and macro-longitudinal studies have shown that feeling younger is related to physical fitness and exercise. Yet, there is limited knowledge on the effects of physical activity on subjective age in daily life and moderators of this association. We thus aim to investigate the association of momentary physical activity with momentary subjective age, expecting that more activity is related to feeling younger. We further expect that concurrent pain experience attenuates this relationship. N = 54 participants aged 50-62 years (Mage = 56.1 years, 75% female) wore chest-sensors measuring their physical activity (step count, movement acceleration) for one week and reported on their subjective age five times per day. Multilevel regression analyses revealed between and within-person variation in momentary subjective age (ICC = 0.74), pain (ICC = 0.63) and physical activity (ICC Moac30 = 0.078, steps30 = 0.053). Pain emerged as a consistent predictor of momentary subjective age (b = 4.64, p = 0.000), whereas results were mixed for the physical activity measures. No significant moderating effect of pain was observed on the relationship between physical activity and subjective age. Our study shows the importance of pain experiences for momentary subjective age, whereas the role of momentary physical activity needs further exploration.

Neural responses to stress and alcohol cues in individuals with pain with and without alcohol use disorder

Pain and alcohol use disorder (AUD) frequently co-occur, but the underlying neurobiology is not well-understood. Although many studies have reported disruptions in stress and reward cue-elicited neural reactivity and heightened alcohol craving in individuals with AUD, little is known about these constructs among patients who experience pain. Here, individuals with pain (Pain+, n = 31) and without pain (Pain-, n = 37) completed a well-validated functional magnetic resonance imaging (fMRI) paradigm involving stress (S), alcohol (A) and neutral (N) cue exposure with repeated alcohol craving assessments. Using whole-brain, voxel-based analyses (p < 0.001, whole-brain cluster correction at α < .05), the Pain+ versus Pain- group evidenced greater dorsal anterior cingulate cortex and left amygdala hyperactivation during N, but hypoactivation during the S-N contrast. Additionally, Pain+ exhibited blunted right anterior insular cortex (AIC) during S-N and blunted anteromedial thalamus and left AIC with hyperactive orbitofrontal cortex (OFC) during A-N. Exploratory analyses further revealed that individuals with pain and AUD (n = 17) relative to pain alone (n = 14) showed hyperactive bilateral AIC and hypoactive right dorsal caudate during A-N. Alcohol cue-induced craving, significantly higher in Pain+ (p = 0.03), correlated with blunted right AIC and OFC responses during A-N. In sum, these results provide first evidence of heightened alcohol cue-elicited craving and disrupted stress- and alcohol cue-reactivity within corticostriatal-limbic regions implicated in negative affect and preoccupation/anticipation stages of AUD in those with pain and with comorbid pain and AUD. Future investigations of pain-AUD interaction are needed that include systematic pain assessment and longitudinal designs with larger sample sizes.

Effect of dog-owner interaction on post-operative pain perception and stress of dogs and variability in their behavioural patterns

Pain, a multifaceted condition associated with actual or potential tissue damage, transcends nociception and is characterised as a subjective, sensory, and emotional experience. Extensive literature describing the adverse effects of untreated post-surgical pain emphasises the necessity of a comprehensive pain management protocol, incorporating both pharmacological and non-pharmacological strategies to ensure successful patient outcomes. The present study aimed to determine whether a positive dog-owner interaction influences post-operative pain perception and stress (POPPS), as well as behavioural inactive rate variability in bitches that underwent elective surgery. Randomly selected bitches (n = 18) underwent ovariohysterectomy. Eight bitches experienced a 45-min visit post-surgery (VPS) characterised by positive dog-owner interaction, while the remaining ten did not (NVPS). Utilising the validated Short Form of the Glasgow Composite Measure Pain Scale (CMPS-SF) to assess acute pain in dogs via stress-related behaviours, a significant decrease in POPPS was evident in the VPS group after the 45-min dog-owner interaction at T3 (1 h after post-sedation recovery), in contrast to the NVPS group. CMPS-SF-associated descriptive items 'Nervous/Anxious/Fearful' and 'Happy Content or Happy and Bouncy' decreased and increased, respectively, with dog-owner positive interaction in the VPS group. The inactivity rate was significantly lower in VPS bitches after the post-surgery 45-min dog-owner interaction than in NVPS bitches. This preliminary study suggests that the owner's presence reduces POPPS and may improve the dogs' welfare while undergoing routine surgeries.

Temporomandibular disorder pain is associated with increased sick leave and reduced health related quality of life

BACKGROUND

Temporomandibular disorders (TMD) are the most common reason for chronic pain in the orofacial area and significantly impact the lives of those affected. The role of lifestyle factors in TMD, however, remains less explored. This cohort study aims to estimate TMD prevalence by addressing potential selection biases and to evaluate the association between TMD and lifestyle factors with a specific focus on sick leave and health related quality of life.

METHODS

By linking data on TMD in the general population in Västerbotten, northern Sweden (n = 180,000) to health survey data (n = 120,000), information on sociodemographic factors and quality of life was available for 52,961 individuals (50.6% women) with a mean age of 53 years. We applied inverse probability weighting to adjust for selection bias and Poisson regression to explore associations with TMD.

RESULTS

TMD prevalence was 9.2% during the study period, being higher in women (12.9%) than men (5.4%). Weighting for varying visiting frequencies did not affect TMD prevalence (average difference 0.4% points). Individuals with TMD, especially women, reported more sick leave and use of pain medication, with a significant association between TMD and increased sick leave (prevalence ratio 1.89, 95% CI: 1.78-2.01) among both women and men. In addition, TMD was associated with a lower health related quality of life (p < 0.001).

CONCLUSION

The association of TMD with sick leave highlights the condition's profound impact on the lives of affected individuals. These findings underscore the influence of TMD on work life and the burden of TMD on the societal level.

SIGNIFICANCE STATEMENT

The findings provide insight into how TMD affect individuals, by incorporating lifestyle factors, social determinants and the impact of sick leave at a population level. By incorporating these areas into the study of TMD, we can deepen our understanding of how TMD affects individuals' lives. This approach may also create opportunities to develop more comprehensive strategies to address TMD, focusing on broader implications beyond the clinical symptoms.

The relationship between traumatic exposure and pain perception in children: the moderating role of posttraumatic symptoms

ABSTRACT

Adverse childhood experiences (ACEs) affect approximately half of all children worldwide. These experiences have been linked to increased pain sensitivity in adulthood and a higher likelihood of developing severe chronic pain. However, most studies have assessed the effects of ACEs retrospectively, long after they occurred, leaving room for other factors to influence the observed outcomes. We investigated, for the first time, the association between ACEs and concurrent pain perception among young children who live in a conflict zone and are consistently exposed to potentially traumatic experiences. Participants were 60 elementary school children (ages 8-11 years) living in conflict regions (n = 39) or nonconflict regions (n = 21). Posttraumatic stress symptom (PTSS) severity, traumatic exposure, pressure pain threshold (PPT), and mechanical detection threshold (MDT) were measured. Trauma-exposed children had significantly lower PPT than did controls, but MDT was similar across groups. Pressure pain threshold correlated positively with proximity to the conflict zone and inversely with traumatic exposure magnitude and PTSS severity. In addition, PTSSs moderated the relationship between repeated traumatic exposure and PPT. Children with higher PTSS severity displayed pain hypersensitivity regardless of their traumatic exposure level, whereas in children with lower PTSS severity, greater traumatic exposure correlated with pain hypersensitivity. The results suggest that ACEs among children lead to concurrent pain hypersensitivity and distress and may put them at elevated risk of chronic pain early in life. In addition, our findings emphasize the need for identifying children with various PTSS levels to provide tailored interventions and mitigate the long-term negative effects of ACEs.

Impact of migraine and fibromyalgia on temporomandibular disorder: A retrospective study on pain, psychological factors and quality of life

OBJECTIVES

This study assessed the impact of migraine and fibromyalgia (FM) in TMD patients, focusing on pain, anxiety, depression, and quality of life (QoL). Additionally, we investigated how these variables relate to the total number of comorbidities to gain insights into their interactions.

METHODS

A retrospective data collection was conducted during January 2016 to December 2022, involving 409 adult TMD patients. TMD patients were categorised into four groups: those without comorbidity (TMD-only) and those with comorbid migraine and/or fibromyalgia (TMD + MG, TMD + FM and TMD + MG + FM). Quantitative variables were compared among them. Linear regression was used to analyse the associations between these variables.

RESULTS

Most of study population were women (79%) with a mean age of 44.43 years. TMD + MG patients reported longer pain duration, higher pain scores and greater pain interference compared with TMD-only patients. Similarly, TMD + FM patients had higher pain intensity than patients with TMD only. Both the TMD + MG and TMD + FM groups had higher levels of anxiety, depression, and health impairment compared with patients with TMD only. Patients with all three pain conditions (TMD + MG + FM) experienced the longest pain duration, highest pain intensity, psychological distress, and impaired QoL. The result showed positive associations between pain outcomes, psychological measures, pain's impact on QoL, and the number of comorbidities and a negative association between overall health states and the number of comorbidities.

CONCLUSIONS

These findings underscore the importance of considering the presence of comorbidities and addressing physical and psychological aspects in the management of TMD patients.

Multimodal functional imaging and clinical correlates of pain regions in chronic low-back pain patients treated with spinal cord stimulation: a pilot study

Objective

Spinal cord stimulation (SCS) is an invasive treatment option for patients suffering from chronic low-back pain (cLBP). It is an effective treatment that has been shown to reduce pain and increase the quality of life in patients. However, the activation of pain processing regions of cLBP patients receiving SCS has not been assessed using objective, quantitative functional imaging techniques. The purpose of the present study was to compare quantitative resting-state (rs)-fMRI and arterial spin labeling (ASL) measures between SCS patients and healthy controls and to correlate clinical measures with quantitative multimodal imaging indices in pain regions.

Methods

Multi-delay 3D GRASE pseudo-continuous ASL and rs-fMRI data were acquired from five patients post-SCS with cLBP and five healthy controls. Three ASL measures and four rs-fMRI measures were derived and normalized into MNI space and smoothed. Averaged values for each measure from a pain atlas were extracted and compared between patients and controls. Clinical pain scores assessing intensity, sensitization, and catastrophizing, as well as others assessing global pain effects (sleep quality, disability, anxiety, and depression), were obtained in patients and correlated with pain regions using linear regression analysis.

Results

Arterial transit time derived from ASL and several rs-fMRI measures were significantly different in patients in regions involved with sensation (primary somatosensory cortex and ventral posterolateral thalamus [VPL]), pain input (posterior short gyrus of the insula [PS]), cognition (dorsolateral prefrontal cortex [DLPC] and posterior cingulate cortex [PCC]), and fear/stress response (hippocampus and hypothalamus). Unidimensional pain rating and sensitization scores were linearly associated with PS, VPL, DLPC, PCC, and/or amygdala activity in cLBP patients.

Conclusion

The present results provide evidence that ASL and rs-fMRI can contrast functional activation in pain regions of cLBP patients receiving SCS and healthy subjects, and they can be associated with clinical pain evaluations as quantitative assessment tools.

Emotion regulation skills-focused interventions for chronic pain: A systematic review and meta-analysis

OBJECTIVES

To investigate the effect of emotion regulation skills-focused (ERSF) interventions to reduce pain intensity and improve psychological outcomes for people with chronic pain and to narratively report on safety and intervention compliance.

METHODS

Six databases and four registries were searched for randomized controlled trials (RCTs) up to 29 April 2022. Risk of bias was evaluated using the Cochrane RoB 2.0 tool, and certainty of evidence was assessed according to the Grading, Assessment, Development and Evaluation (GRADE). Meta-analyses for eight studies (902 participants) assessed pain intensity (primary outcome), emotion regulation, affect, symptoms of depression and anxiety, and pain interference (secondary outcomes), at two time points when available, post-intervention (closest to intervention end) and follow-up (the first measurement after the post-intervention assessment).

RESULTS

Compared to TAU, pain intensity improved post-intervention (weighted mean difference [WMD] = -10.86; 95% confidence interval [CI] [-17.55, -2.56]) and at follow-up (WMD = -11.38; 95% CI [-13.55, -9.21]). Emotion regulation improved post-intervention (standard mean difference [SMD] = 0.57; 95% CI [0.14, 1.01]), and depressive symptoms improved at follow-up (SMD = -0.45; 95% CI [-0.66, -0.24]). Compared to active comparators, anxiety symptoms improved favouring the comparator post-intervention (SMD = 0.10; 95% CI [0.03, 0.18]), and compared to CBT, pain interference improved post-intervention (SMD = -0.37; 95% CI [-0.69, -0.04]). Certainty of evidence ranged from very low to moderate.

SIGNIFICANCE

The findings provide evidence that ERSF interventions reduce pain intensity for people with chronic pain compared to usual treatment. These interventions are at least as beneficial to reduce pain intensity as the current gold standard psychological intervention, CBT. However, the limited number of studies and certainty of evidence mean further high-quality RCTs are warranted. Additionally, further research is needed to identify whether ERSF interventions may be more beneficial for specific chronic pain conditions.

CRF regulates pain sensation by enhancement of corticoaccumbal excitatory synaptic transmission

Both peripheral and central corticotropin-releasing factor (CRF) systems have been implicated in regulating pain sensation. However, compared with the peripheral, the mechanisms underlying central CRF system in pain modulation have not yet been elucidated, especially at the neural circuit level. The corticoaccumbal circuit, a structure rich in CRF receptors and CRF-positive neurons, plays an important role in behavioral responses to stressors including nociceptive stimuli. The present study was designed to investigate whether and how CRF signaling in this circuit regulated pain sensation under physiological and pathological pain conditions. Our studies employed the viral tracing and circuit-, and cell-specific electrophysiological methods to label the CRF-containing circuit from the medial prefrontal cortex to the nucleus accumbens shell (mPFCCRF-NAcS) and record its neuronal propriety. Combining optogenetic and chemogenetic manipulation, neuropharmacological methods, and behavioral tests, we were able to precisely manipulate this circuit and depict its role in regulation of pain sensation. The current study found that the CRF signaling in the NAc shell (NAcS), but not NAc core, was necessary and sufficient for the regulation of pain sensation under physiological and pathological pain conditions. This process was involved in the CRF-mediated enhancement of excitatory synaptic transmission in the NAcS. Furthermore, we demonstrated that the mPFCCRF neurons monosynaptically connected with the NAcS neurons. Chronic pain increased the protein level of CRF in NAcS, and then maintained the persistent NAcS neuronal hyperactivity through enhancement of this monosynaptic excitatory connection, and thus sustained chronic pain behavior. These findings reveal a novel cell- and circuit-based mechanistic link between chronic pain and the mPFCCRF → NAcS circuit and provide a potential new therapeutic target for chronic pain.

Examining Reactivity and Recovery Patterns of Pain-Evoked Cortisol and Alpha-Amylase Trajectories: Relations Between Psychological Markers of Risk and Resilience

Chronic low back pain (cLBP) is one of the leading causes of disability globally and represents an enormous burden to aging adults. While numerous factors contribute to cLBP, dysregulation in the hypothalamic-pituitary-adrenal axis and autonomic nervous system functioning have been implicated in its pathogenesis. It is well documented that negative psychological states can modulate biological stress responsivity in chronic pain; however, little is known regarding the influence of positive psychological factors in this relationship. The aim of this study was to examine the association between psychological risk and resilience factors with patterns of physiological stress reactivity and recovery in 60 older adults with cLBP. Participants completed measures of hope, optimism, pain catastrophizing, and perceived stress, and underwent psychophysical pain testing assessing responses to painful pressure, heat, and cold stimuli. Salivary samples were obtained prior to pain induction and at 7 time points spanning 90 minutes after pain testing terminated. To examine reactivity and recovery profiles in hypothalamic-pituitary-adrenal axis and autonomic nervous system function, samples were assayed for cortisol and alpha-amylase, respectively. Results revealed higher levels of hope and optimism were associated with increased cortisol reactivity (p's < .003) and more rapid recovery (p's = .001). Further, pain catastrophizing and perceived stress were associated with cortisol reactivity, with lower levels of these factors predicting larger increases in cortisol from baseline to peak levels (p's < .04). No significant differences in reactivity or recovery patterns emerged for alpha-amylase. Overall, findings highlight the role of psychological risk and resilience factors in modulating physiological stress reactivity. PERSPECTIVE: This article investigated whether psychosocial risk and resilience factors were associated with stress reactivity and recovery in response to laboratory-based pain testing in older adults with chronic low back pain. Results indicate that high resilience factors may be protective by modulating adrenocortical reactivity and recovery profiles.

Neuropathic pain, mood, and stress-related disorders: A literature review of comorbidity and co-pathogenesis

Neuropathic pain can be caused by multiple factors, and its prevalence can reach 10% of the global population. It is becoming increasingly evident that limited or short-lasting response to treatments for neuropathic pain is associated with psychological factors, which include psychiatric comorbidities known to affect quality of life. It is estimated that 60% of patients with neuropathic pain also experience depression, anxiety, and stress symptoms. Altered mood, including stress, can be a consequence of several painful conditions but can also favor pain chronicization when preexisting. Despite the apparent tight connection between clinical pain and mood/stress disorders, the exact physiological mechanisms remain unclear. This review aims to provide an overview of state-of-the-art research on the mechanisms of pain related to the pathophysiology of depression, anxiety, and stress disorders.

Accelerated construction of stress relief music datasets using CNN and the Mel-scaled spectrogram

Listening to music is a crucial tool for relieving stress and promoting relaxation. However, the limited options available for stress-relief music do not cater to individual preferences, compromising its effectiveness. Traditional methods of curating stress-relief music rely heavily on measuring biological responses, which is time-consuming, expensive, and requires specialized measurement devices. In this paper, a deep learning approach to solve this problem is introduced that explicitly uses convolutional neural networks and provides a more efficient and economical method for generating large datasets of stress-relief music. These datasets are composed of Mel-scaled spectrograms that include essential sound elements (such as frequency, amplitude, and waveform) that can be directly extracted from the music. The trained model demonstrated a test accuracy of 98.7%, and a clinical study indicated that the model-selected music was as effective as researcher-verified music in terms of stress-relieving capacity. This paper underlines the transformative potential of deep learning in addressing the challenge of limited music options for stress relief. More importantly, the proposed method has profound implications for music therapy because it enables a more personalized approach to stress-relief music selection, offering the potential for enhanced emotional well-being.

The relationship between neonatal stress in preterm infants and developmental outcomes at the corrected age of 24-30 months

Aim

The aim of research was to study the relationship between the stress experienced by preterm infants in the neonatal intensive care unit (NICU) and developmental status in the follow up, and to establish factors, associated with their neurodevelopment.

Methods

The first stage of research involved measuring stress markers (cortisol, melatonin) in infants (n = 56) during their NICU stay; the second phase assessed the developmental status at the corrected age of 24-30 months.

Results

The total ASQ-3 score, communication, problem solving, and personal-social skills scores at the corrected age of 24-30 months were positively correlated with melatonin level determined in the neonatal period (r = 0.31, p = 0.026; r = 0.36, p = 0.009; r = 0.30, p = 0.033, and r = 0.32; p = 0.022 respectively). In the same time, ASQ-3 communication and personal-social scores were negatively correlated with cortisol level (r = -0.31, p = 0.043; r = -0.35, p = 0.022). The ROC-curve analysis revealed that a decrease of melatonin below 3.44 ng/mL and 3.71 ng/mL during the neonatal period could predict communication and problem-solving delay, respectively. An increase in cortisol above 0.64 mcg/dl is predictive in personal-social delay. Negative correlation was identified between the NICU and total hospital stay duration and ASQ-3 communication scores in the follow-up (r = -0.27; p = 0.049 and r = -0.41; p = 0.002, respectively). The duration of mechanical ventilation was negatively correlated with gross motor scores (r = -0.46; p = 0.043). Apgar score was positively correlated with ASQ-3 communication (r = 0.29; p = 0.032) and personal-social scores (r = 0.28; p = 0.034); maternal age-with ASQ-3 total (r = 0.29; p = 0.034), communication (r = 0.37; p = 0.006), and personal-social scores (r = 0.29; p = 0.041). Positive correlations were observed between gestational age and communication scores (r = 0.28; p = 0.033). Infants who suffered neonatal sepsis had significantly often delay of communication (p = 0.014) and gross motor skills (p = 0.016). Children who required mechanical ventilation were more likely to have communication delay (p = 0.034).

Conclusion

Developmental outcomes in preterm infants at the corrected age of 24-30 months were associated with neonatal stress. Correlations between the communication, problem-solving and personal-social development in the follow up and cortisol and melatonin levels determined in the neonatal period supported this evidence. Factors as low gestational age, duration of hospital and NICU stay, mechanical ventilation, and sepsis were associated with more frequent delays in communication, gross motor and problems-solving skills.

Personalizing Injury Management and Recovery: A Cross-Sectional Investigation of Musculoskeletal Injuries and Quality of Life in Athletes

Purpose

The study explores the impact of Musculoskeletal Injuries on the quality of life in youth athletes, aiming to understand the extent of these injuries' effects on their physical and mental wellbeing.

Patients and Methods

This cross-sectional study included 130 youth athletes, using questionnaires to collect data on demographics, training exposures (averaging 11±3.8 hours/week), overuse symptoms (using the Oslo Sports Trauma Research Center Overuse Injury Questionnaire), acute injury history, and overall wellbeing (assessed by the RAND 36-item Short Form Health Survey).

Results

Findings indicated that 55.4% of participants had suffered an acute injury in the past 6 months, leading to an average of 4 weeks of time loss. The mean score for OSTRC-O Scores was 16.8±6.4, with knee overuse averaging 21.3± 8.8. In terms of wellbeing, physical and mental health scores were 82.4±15.3 and 81.7±14.1 respectively. There were significant correlations between higher overuse scores and poorer physical functioning (r=-0.42), bodily pain (r=-0.38), vitality (r=-0.32), and mental health (r=-0.31). Acute injuries were linked with worse physical functioning and role limitations. Regression analysis showed that both overuse and acute injuries predicted poorer physical health.

Conclusion

The study underscores the significant prevalence of musculoskeletal injuries among youth athletes and delineates their profound impact on the quality of life, encompassing both the physical and mental health realms. These findings advocate for the critical integration of preventive measures and personalized training protocols, spotlighting the pivotal role of comprehensive biopsychosocial strategies in nurturing athletes' overall wellbeing. By prioritizing the quality of life as a key outcome, this research advocates for a more nuanced approach to injury management and recovery.

Mindfulness-Based Interventions for Perioperative Pain Management and Opioid Risk Reduction Following Surgery: A Stepped Care Approach

Surgical procedures often improve health and function but can sometimes also result in iatrogenic effects, including chronic pain and opioid misuse. Due to the known risks of opioids and the physical, emotional, and financial suffering that often accompanies chronic pain, there has been a call for greater use of complementary non-pharmacological treatments like mindfulness-based interventions. Mindfulness can be broadly described as an attentional state involving moment-by-moment meta-awareness of thoughts, emotions, and body sensations. An expanding number of randomized clinical trials have found strong evidence for the value of mindfulness techniques in alleviating clinical symptomology relevant to surgical contexts. The purpose of this review is to examine the empirical evidence for the perioperative use of mindfulness interventions. We present a mindfulness-based stepped care approach that first involves brief mindfulness to treat preoperative pain and anxiety and prevent development of postoperative chronic pain or opioid misuse. More extensive mindfulness-based interventions are then provided to patients who continue to experience high pain levels or prolonged opioid use after surgery. Finally, we review psychophysiological mechanisms of action that may be integral to the analgesic and opioid sparing effects of mindfulness.

Chronic pain as an emergent property of a complex system and the potential roles of psychedelic therapies

Despite research advances and urgent calls by national and global health organizations, clinical outcomes for millions of people suffering with chronic pain remain poor. We suggest bringing the lens of complexity science to this problem, conceptualizing chronic pain as an emergent property of a complex biopsychosocial system. We frame pain-related physiology, neuroscience, developmental psychology, learning, and epigenetics as components and mini-systems that interact together and with changing socioenvironmental conditions, as an overarching complex system that gives rise to the emergent phenomenon of chronic pain. We postulate that the behavior of complex systems may help to explain persistence of chronic pain despite current treatments. From this perspective, chronic pain may benefit from therapies that can be both disruptive and adaptive at higher orders within the complex system. We explore psychedelic-assisted therapies and how these may overlap with and complement mindfulness-based approaches to this end. Both mindfulness and psychedelic therapies have been shown to have transdiagnostic value, due in part to disruptive effects on rigid cognitive, emotional, and behavioral patterns as well their ability to promote neuroplasticity. Psychedelic therapies may hold unique promise for the management of chronic pain.

Personality systems interactions theory: an integrative framework complementing the study of the motivational and volitional dynamics underlying adjustment to chronic pain

In the endeavor to advance our understanding of interindividual differences in dealing with chronic pain, numerous motivational theories have been invoked in the past decade. As they focus on relevant, yet different aspects of the dynamic, multilevel processes involved in human voluntary action control, research findings seem fragmented and inconsistent. Here we present Personality Systems Interactions theory as an integrative meta-framework elucidating how different motivational and volitional processes work in concert under varying contextual conditions. PSI theory explains experience and behavior by the relative activation of four cognitive systems that take over different psychological functions during goal pursuit. In this way, it may complement existing content-related explanations of clinical phenomena by introducing a functional, third-person perspective on flexible goal management, pain acceptance and goal maintenance despite pain. In line with emerging evidence on the central role of emotion regulation in chronic pain, PSI theory delineates how the self-regulation of positive and negative affect impacts whether behavior is determined by rigid stimulus-response associations (i.e., habits) or by more abstract motives and values which afford more behavioral flexibility. Along with testable hypotheses, multimodal interventions expected to address intuitive emotion regulation as a central process mediating successful adaptation to chronic pain are discussed.

Effects of Geometric Sound on Brainwave Activity Patterns, Autonomic Nervous System Markers, Emotional Response, and Faraday Wave Pattern Morphology

This study introduces Geometric Sound as a subfield of spatial sound featuring audio stimuli which are sonic holograms of mathematically defined 3D shapes. The effects of Geometric Sound on human physiology were investigated through EEG, heart rate, blood pressure, and a combination of questionnaires monitoring 50 healthy participants in two separate experiments. The impact of Geometric Sound on Faraday wave pattern morphology was further studied. The shapes examined, pyramid, cube, and sphere, exhibited varying significant effects on autonomic nervous system markers, brainwave power amplitude, topology, and connectivity patterns, in comparison to both the control (traditional stereo), and recorded baseline where no sound was presented. Brain activity in the Alpha band exhibited the most significant results, additional noteworthy results were observed across analysis paradigms in all frequency bands. Geometric Sound was found to significantly reduce heart rate and blood pressure and enhance relaxation and general well-being. Changes in EEG, heart rate, and blood pressure were primarily shape-dependent, and to a lesser extent sex-dependent. Pyramid Geometric Sound yielded the most significant results in most analysis paradigms. Faraday Waves patterns morphology analysis indicated that identical frequencies result in patterns that correlate with the excitation Geometric Sound shape. We suggest that Geometric Sound shows promise as a noninvasive therapeutic approach for physical and psychological conditions, stress-related disorders, depression, anxiety, and neurotrauma. Further research is warranted to elucidate underlying mechanisms and expand its applications.

Life course socioeconomic status, chronic pain, and the mediating role of allostatic load: findings from the midlife in the United States

Introduction

Low socioeconomic status (SES) has been linked to chronic pain (CP); however, the mechanisms by which SES over the life course influences downstream CP outcomes remain unclear.

Methods

This study utilizes data from the Midlife in the United States (MIDUS) survey, a prospective sample of community-dwelling individuals (N=781), to investigate the chain of risk additive model of SES in relation to CP. Additionally, the study examines the mediating role of allostatic load (AL) in the relationship between life course SES and CP. Confirmatory factor analysis was employed to capture the multidimensionality of life course SES and path analysis was used to examine the direct and indirect effects on CP. AL was computed by quartile-based summation and by latent class analysis.

Results

Results indicated lower SES in MIDUS 2 was associated with greater high-interference CP odds in MIDUS 3 (OR=1.069, 95% CI=1.006-1.136, P < 0.05) and no association was found between distal SES and levels of CP interference. Similarly, no significant relationship was observed between SES and the number of CP locations. Additionally, no additive effects of SES were found, and AL did not present mediation effects on the association between life course SES and CP.

Discussion

The present study emphasizes the importance of directly proximal effects of SES on CP, underscoring the need for equitable distribution of health resources and the implementation of policies focused on diminishing socioeconomic inequalities. Further research is needed to examine alternative pathways by which proximal SES impact CP.

Rasch analysis of the Depression, Anxiety, and Stress Scale in patients with chronic pain

OBJECTIVE

Questionnaires are commonly used to assess and screen pain-related, psychological symptoms in patients with chronic pain. In Germany, the "German pain questionnaire" provided by the German Pain Society used for this purpose includes the Depression, Anxiety, and Stress Scale (DASS). This study aims to analyze the DASS by fitting its data to the Rasch model to test the psychometric quality.

STUDY DESIGN AND SETTING

In this cross-sectional study, 932 patients with chronic pain answered the DASS. The 21-item short version was tested via Rasch analysis using the parameters threshold order, fit to the model, Differential Item Functioning, unidimensionality and reliability.

RESULTS

The Rasch analysis results showed a low reliability, misfitting items, Differential Item Functioning or multidimensionality. It was necessary to remove items from the subscales to improve fit to the Rasch model. A revised depression subscale of the DASS-21 was the only scale that achieved all the required psychometric parameters. The summation of all items to a total scale was not supported.

CONCLUSION

More research is required on somatic free measurement of psychological symptoms in patients with chronic pain. The results demonstrate that the development of a new instrument or a revision of existing instruments for screening of psychological symptoms in chronic pain are needed.

Association of Pain-Related Anxiety and Abdominal Muscle Thickness during Standing Postural Tasks in Patients with Non-Specific Chronic Low Back Pain

Objective

The purpose of this study was to evaluate the association of pain-related anxiety on abdominal muscles thickness during standing postural tasks among individuals with chronic low back pain (CLBP).

Methods

We obtained responses to a pain-related anxiety symptoms questionnaire from 50 participants with CLBP. We then separated participants into high (11 men, 14 women) and low pain-related anxiety (13 men, 12 women) groups and compared assessments of their lateral abdominal muscles thickness during standing tasks on a computerized balance assessment device, using one static level and 2 movable levels (levels 6 and 3 are represented easy and difficult tasks respectively).

Results

We found a significant interaction effect of standing difficulty (2 levels) and abdominal muscle thickness (transverse abdominis, oblique internal and oblique external muscles) (p< .001, effect size= .7). The high pain-related anxiety group exhibited greater abdominal muscle thickness during standing postural tasks compared with the low pain-related anxiety group (p< .05, mean difference= .04-.06) except for the internal oblique muscle during the difficult standing task (p=.2).

Conclusion

We suggest that, among individuals with CLBP, pain-related anxiety and psychological pain-related anxiety may be possibly associated with abdominal muscles thickness during dynamic standing.

Environmental factors and their impact on chronic pain development and maintenance

It is more than recognized and accepted that the environment affects the physiological responses of all living things, from bacteria to superior vertebrates, constituting an important factor in the evolution of all species. Environmental influences range from natural processes such as sunlight, seasons of the year, and rest to complex processes like stress and other mood disorders, infections, and air pollution, being all of them influenced by how each creature deals with them. In this chapter, it will be discussed how some of the environmental elements affect directly or indirectly neuropathic pain, a type of chronic pain caused by a lesion or disease of the somatosensory nervous system. For that, it was considered the edge of knowledge in translational research, thus including data from human and experimental animals as well as the applicability of such findings.

Cortisol as a Marker of Pain and Distress After Acute Musculoskeletal Trauma

OBJECTIVES

The best available predictors of chronic pain development broadly encompass baseline metrics of cognition (ie, beliefs/expectations) about the trauma and resulting symptoms. In the context of musculoskeletal trauma, we have previously shown the Traumatic Injuries Distress Scale (TIDS) capable of risk-stratifying cohorts for chronic pain development. Here, we explore whether the physiological marker cortisol shows meaningful associations with cognitions predictive of pain outcomes.

METHODS

Data for these cross-sectional analyses were drawn from an observational study that recruited 130 participants presenting to the hospital with pain related to a recent noncatastrophic Musculoskeletal trauma. Cortisol was measured from the participant's hair, saliva, and blood. In addition to pain and distress questionnaires, metadata such as age, sex, body mass index (BMI), adverse childhood events, pretrauma stress levels, and pre-existing physical/psychological comorbidities were collected.

RESULTS

We found no significant associations between cortisol levels and pain or distress in isolation. When stratified by person-level variables, associations were revealed with distress (TIDS) in young age and low pretrauma stress subgroups (hair cortisol) and low BMI (blood cortisol). Through hierarchical regression analysis, we found the "cortisol X age" or "cortisol X stress" interaction terms significantly improved TIDS prediction beyond either variable in isolation (Age: ∆ R2 =15.1%; pretrauma stress: ∆ R2 =9.1%).

DISCUSSION

Our findings suggest that while linear correlations between pain-related distress and cortisol may be overly simplistic, certain person-level variables such as age, pretrauma stress, and BMI are worthy of consideration for experimental design or confounder characterization in future studies of pain and distress following musculoskeletal injuries especially when "trait" (hair) cortisol is the predictor variable.

Investigating the Impact of Stress on Pain: A Scoping Review on Sense of Control, Social-Evaluative Threat, Unpredictability, and Novelty (STUN Model)

Background

Stress can have paradoxical effects on pain, namely hyperalgesia and hypoalgesia. Four situational characteristics activate the hypothalamic-pituitary-adrenal axis, leading to a physiological stress response: lacking Sense of control, social-evaluative Threat, Unpredictability and Novelty (STUN). This scoping review reports on the types of evidence published on the effects of STUN characteristics on pain outcomes.

Databases/Data Treatment

Searches of primary electronic databases were performed to identify articles published on adults between 1990 and 2021 that contained search terms on pain and stress/STUN characteristics. A total of 329 articles were included in the analysis.

Results

Only 3.3% of studies examined simultaneously >1 STUN component. Almost all observational studies (177/180) examined the association between perceived stress and pain without measuring physiological stress responses. Of the 130 experimental studies, 78 (60.0%) manipulated stressful characteristics through nociception, and only 38.5% assessed if/how stress manipulation impacted perceived stress.

Conclusion

There is a clear lack of integration of the characteristics that trigger a physiological stress response in the pain field. Only 3.3% of studies examined simultaneously more than one STUN component and there is an unequal attention given to individual components of the STUN framework. Recommendations for future research include selection of stress manipulations/measurements that are more precisely inducing/reflecting neurobiological mechanisms of stress responses to insure valid integration of scientific knowledge.

Pain in the Context of Virtual Neuropsychological Assessment of Older Adults

OBJECTIVE

Pain and cognitive impairment are prevalent and often co-occur in older adults. Because pain may negatively affect cognitive test performance, identification of pain in the context of neuropsychological evaluation is important. However, pain detection based on self-report presents challenges, and pain is often under-detected in this population. Alternative methods (e.g., video-based automatic coding of facial biomarkers of pain) may facilitate pain identification and thus enhance interpretation of neuropsychological evaluation results.

METHOD

The current study examined pain in the context of virtual neuropsychological assessment in 111 community-dwelling older adults, first seeking to validate the use of software developed to automatically code biomarkers of pain. Measures of pain, including self-report of acute and chronic pain and automatic coding of pain, were compared while participants completed neuropsychological testing.

RESULTS

Self-reported pain was negatively associated with poorer performance on a measure of executive function (both acute and chronic pain) and a global cognitive screening measure (acute pain only). However, self-reported acute and chronic pain did not correlate significantly with most neuropsychological tests. Automatic coding of pain did not predict self-report of pain or performance on neuropsychological tests beyond the influence of demographic factors and psychological symptoms.

CONCLUSIONS

Though results were largely not significant, correlations warrant further exploration of the influence of pain on neuropsychological test performance in this context to ensure that pain does not influence test performance in individuals with higher levels of pain and in other samples.

Allostatic load and chronic pain: a prospective finding from the national survey of midlife development in the United States, 2004-2014

BACKGROUND

Previous research has demonstrated a correlation between chronic stress and chronic pain (CP). However, there have been few studies examining the prospective association of allostatic load (AL)-the biological processes related to stress-with CP.

METHODS

We firstly conducted latent class analysis to identify phenotypes of AL using a community-dwelling sample, the Midlife in the United States. Multinomial logistic regression models were used to examine the prospective association between phenotypes of AL at MIDUS 2 biomarker project and the presence of CP, CP interference and the number of CP sites at MIDUS 3.

RESULTS

Three phenotypes of AL, low biological dysregulation, parasympathetic dysregulation and metabolic dysregulation, were identified. Compared to low biological dysregulation group, participants experiencing metabolic dysregulation phenotype of AL at MIDUS 2 had higher risks of having high-interference CP (RRR = 2.00, 95% CI: 1.06, 3.79, P < 0.05) and 3 or more CP sites (RRR = 2.03, 95% CI: 1.08, 3.83, P < 0.05) at MIDUS 3.

CONCLUSION

The findings indicate that focusing on mitigating the metabolic dysfunction phenotype of AL has the potential to be an efficacious strategy for alleviating future CP bodily widespreadness and high CP interference.

Psycho-Neuroendocrinology in the Rehabilitation Field: Focus on the Complex Interplay between Stress and Pain

Chronic stress and chronic pain share neuro-anatomical, endocrinological, and biological features. However, stress prepares the body for challenging situations or mitigates tissue damage, while pain is an unpleasant sensation due to nociceptive receptor stimulation. When pain is chronic, it might lead to an allostatic overload in the body and brain due to the chronic dysregulation of the physiological systems that are normally involved in adapting to environmental challenges. Managing stress and chronic pain (CP) in neurorehabilitation presents a significant challenge for healthcare professionals and researchers, as there is no definitive and effective solution for these issues. Patients suffering from neurological disorders often complain of CP, which significantly reduces their quality of life. The aim of this narrative review is to examine the correlation between stress and pain and their potential negative impact on the rehabilitation process. Moreover, we described the most relevant interventions used to manage stress and pain in the neurological population. In conclusion, this review sheds light on the connection between chronic stress and chronic pain and their impact on the neurorehabilitation pathway. Our results emphasize the need for tailored rehabilitation protocols to effectively manage pain, improve treatment adherence, and ensure comprehensive patient care.

Integrative Medicine for Cancer-Related Pain: A Narrative Review

Cancer-related pain (C-RP) is a prevalent and debilitating concern among patients with cancer, with conventional treatments limited in their ability to provide adequate relief, and by the adverse effects associated with their use. Complementary and integrative medicine (CIM) modalities have been shown to be potentially effective and safe for the treatment of pain and related symptoms, when used in conjunction with conventional medications and under medical supervision. An increasing number of oncology centers provide CIM within their conventional supportive and palliative care service, in an "Integrative Oncology" (IO) setting. A large body of clinical research, including systematic reviews and guidelines such as those published in 2022 by the Society for Integrative Oncology (SIO), in collaboration with the American Society for Clinical Oncology (ASCO), support the use of some CIM modalities for C-RP and related concerns. These include acupuncture for general and peri-operative/procedural pain, as well as aromatase inhibitor-associated arthralgia (AIA); reflexology or acupressure for pain during systemic therapy for cancer; hypnosis for procedural pain or pain due to diagnostic workup; and massage for pain experienced by patients during palliative and hospice care. Further research is needed, within both randomized control trials and pragmatic non-controlled studies which are more reflective of the real-life IO setting. This review summarizes the evidence supporting the use of CIM for C-RP; the analgesic mechanism of the modalities presented; and the challenges facing IO researchers, as well as the implementation of the 2022 SIO-ASCO guideline recommendations.

Exploring the Experience of Living with Pain after Spinal Cord Injury: A Qualitative Study

A spinal cord injury is a life-changing experience that results in functional limitations and an increased risk of secondary health conditions. People with spinal cord injury identify pain as the most devastating health problem following their injury that not only affects their social life but their mental well-being as well. This study is aimed at exploring the lived experience of living with pain by community-dwelling manual wheelchair users with spinal cord injuries. An explorative qualitative design was used to explore their experiences. In-depth interviews were recorded and transcribed, and the data were analysed using inductive thematic content analysis in the MAXQDA v2020. Fifteen manual wheelchair users with paraplegia participated in this study, and four themes were identified from their experience of living with pain: pain constantly lurks, pain is worse than the direct consequences of the SCI, pain is restrictive, and life continues despite the pain. Categories and subcategories included the participants being one with the pain; pain interfering with sleep; feelings of anger, isolation, and suicidal ideation; and uncertainties about what the future holds living with pain. Living with pain after SCI is a challenging feat, and effective management of pain is necessary to improve not only functioning and mobility but also mental health and life satisfaction.

Regular use of acupressure mats reduces perceived stress at subjective but not psychophysiological levels: Insights from a three-week relaxation training

Acupressure mats are promoted as stress management tools for easy and effective self-application, promising reduced stress and increased well-being. However, the scientific evidence for these effects is based on few experimental studies and lacks the examination of acupressure mats as a solitary relaxation tool. Our study aimed to examine which changes in stress and well-being can be expected from the use of acupressure mats by healthy young people on the subjective and psychophysiological level. Unexperienced participants practiced relaxation for three weeks either with an acupressure mat or without any tools (active control group [CG]). As a results, subjective well-being and stress decreased, while sleep quality and concentration endurance increased across groups. Blood pressure (BP), heart rate (HR), pain threshold and pain tolerance did not change significantly from pre- to post-training measurements. Most importantly, no significant differences were found between groups, indicating that training with an acupressure mat yielded no superior effects compared with an active control condition in healthy young students. As a conclusion, taking time to relax has some but limited beneficial effects on the subjective levels independent of the specific method for healthy students. Potential beneficial effects of acupressure mats might be bound to specific impairments, such as tension pain.

Exploring venlafaxine effects on chronic vulvar pain: Changes in mood and pain regulation networks

The etiology of idiopathic pain conditions, such as Provoked vulvodynia (PV), is multifactorial. The efficiency of venlafaxine, serotonin-noradrenaline reuptake inhibitor (SNRIs) in modulating vulvar pain led to the hypothesis that PV might involve central mechanisms. Here, we investigate whether vulvar pain is associated with gene-expression changes in mood, stress and pain systems, including amygdala (Amg), medial prefrontal cortex (mPFC), and periaqueductal gray matter (PAG). Additionally, we examined the analgesic and anxiolytic effects of venlafaxine. We found that the development of chronic vulvar pain in an animal model of PV is associated by overexpression of genes related to neuronal-activity and neuroinflammation in the Amg, mPFC, and PAG. Additionally, changes in the expression of GABA and serotonin synthesis, and reuptake were noted in the Amg and mPFC. Unsurprisingly, anxiety-like behavior and emotional-disorder were observed in rats with chronic vulvar pain. Nevertheless, treatment with venlafaxine (37.5 mg/kg) for one month significantly improves the vulvar hypersensitivity, as well as reduces the anxiety level. More critically, the long-term gene expression adaptation in serotonin receptor and synthesis, GABA synthesis, neuroplasticity, and neuroinflammation in the Amg, mPFC, and PAG, were modulated by venlafaxine in rats with vulvar pain. Our findings suggest that vulvar hypersensitivity induced by inflammation might associated with gene expression changes in brain areas that are involved in mood, stress and pain regulation. These changes probably play a role in central sensitization, and anxiety. Strikingly, enhancing the activity of serotonin and noradrenaline via venlafaxine treatment in rats with vulvar pain induces analgesic and anxiolytic effects.

Differences in characteristics and use of complementary and alternative methods for coping with endometriosis-associated acyclic pelvic pain across adolescence and adulthood

Introduction

Over four million women in the US alone have been diagnosed with endometriosis. For those living with this disease, surgery and hormonal treatment reduce associated pelvic pain in some, while others continue to experience life impacting pain. Therefore, identification of accessible and cost-effective methods of pain reduction to compliment current treatment is urgently needed. Our objective was to quantify the prevalence of complementary and alternative methods used to manage acyclic pelvic pain and their reported benefit among women of different age groups living with endometriosis.

Methods

We used baseline questionnaire data from laparoscopically-confirmed endometriosis cases who completed a WERF EPHect compliant questionnaire in the longitudinal cohort of The Women's Health Study: From Adolescence to Adulthood (A2A). Participants with acyclic pelvic pain were asked to indicate specific methods or activities that either helped or worsened their pelvic/lower abdominal pain. Differences among age groups [adolescent (<18 years), young adult (18-25 years), and adult (>25 years)] were assessed using Fisher's exact test.

Results

Of the 357 participants included in analysis, sleep for coping was reported more frequently among adolescents (n = 59, 57.3%) compared to young adults (n = 40, 44.0%) and adults (n = 19, 31.1%; p = 0.004). Adolescents also reported more frequent use of music (n = 29, 21.2%) than young adults (n = 10, 7.0%) and adults (n = 7, 9.1%; p = 0.001). Exercise worsened pain most commonly among adolescents (n = 82, 59.9%), followed by younger adults (n = 67, 46.9%), and adults (n = 27, 35.1%; p = 0.002).

Discussion

Our analysis of participants in the A2A cohort showed that the prevalence of complementary and alternative methods used for coping with endometriosis-associated acyclic pelvic pain varied by age group. Future studies should aim to provide information that will further inform decisions in making care plans for managing endometriosis-associated pain that is effective, accessible, and tailored to the preferences of the patient.

Chronic restraint stress induces abnormal behaviors in pain sensitivity and cognitive function in mice: the role of Keap1/Nrf2 pathway

Stress is a series of physical and psychological responses to external and internal environmental stimuli. Growing studies have demonstrated the detrimental impacts of acute restraint stress (ARS) and chronic restraint stress (CRS) on animal behavior. However, the related pathogenesis and therapeutic mechanisms remain unclear. Hence, the present study aimed to examine whether unfolded protein response (UPR) and Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2 related factor 2 (Nrf2) pathway are associated with ARS- and CRS- induced abnormal behaviors of pain sensitivity and cognitive function. We here used four behavioral tests to evaluate pain sensitivity and cognitive function in ARS and CRS mice. CRS markedly decreased Paw Withdrawal Mechanical Threshold (PWMT) and Tail-flick Latency (TFL) scores, whereas ARS altered TFL but had no effect on PWMT scores. Additionally, CRS, but not ARS, significantly changed behaviors in nest building behavior and MWMT. Intriguingly, the expression of Keap1 and Nrf2 protein were decreased in the spinal cord and hippocampus in CRS mice, but not in ARS mice. Moreover, neither the ARS nor the CRS groups significantly differed from the control group in terms of endoplasmic reticulum stress (ERS). Taken together, this study demonstrated that CRS could induce abnormal pain sensitivity and cognitive function probably via Keap1/Nrf2 pathway in spinal cord and hippocampus. It is therefore likely that effective intervention of Keap1/Nrf2 pathway may contribute to preventing and treating hyperalgesia and cognitive dysfunction in CRS.

Length of Stay Does Not Predict Change in Epilepsy Monitoring Unit Comfort Questionnaire Scores

ABSTRACT

BACKGROUND: The epilepsy monitoring unit (EMU) is a clinical setting designed to help diagnose and analyze the nature behind a patient's seizures in a hospitalized unit. Patients admitted to an EMU may experience sleep deprivation, withdrawal of antiepileptic medications, and the use of a continuous electroencephalogram. The purpose of this study was to explore change in patient comfort during an EMU admission. METHODS: The Epilepsy Monitoring Unit Comfort Questionnaire (EMUCQ) was used to evaluate the initial stress level of EMU patients on their date of admission versus their fourth day on the unit. RESULTS: The average EMUCQ score from the admission date was 196.6 (26.28), whereas the mean EMUCQ score on the fourth day was 197.8 (24.79). The P value of .802 and t value of 0.25 indicated that the scores were not statistically significantly different. CONCLUSION: Although some scores indicated there was a large change between baseline and follow-up, these scores could not be readily attributed to the patient's length of stay in the unit. Future studies should examine the role of specific variables hypothesized to impact comfort in the EMU.

Hemokinin-1 is a mediator of chronic restraint stress-induced pain

The Tac4 gene-derived hemokinin-1 (HK-1) binds to the NK1 receptor, similarly to Substance P, and plays a role in acute stress reactions and pain transmission in mice. Here we investigated Tac4 mRNA expression in stress and pain-related regions and its involvement in chronic restraint stress-evoked behavioral changes and pain using Tac4 gene-deleted (Tac4-/-) mice compared to C57Bl/6 wildtypes (WT). Tac4 mRNA was detected by in situ hybridization RNAscope technique. Touch sensitivity was assessed by esthesiometry, cold tolerance by paw withdrawal latency from 0°C water. Anxiety was evaluated in the light-dark box (LDB) and open field test (OFT), depression-like behavior in the tail suspension test (TST). Adrenal and thymus weights were measured at the end of the experiment. We found abundant Tac4 expression in the hypothalamic-pituitary-adrenal axis, but Tac4 mRNA was also detected in the hippocampus, amygdala, somatosensory and piriform cortices in mice, and in the frontal regions and the amygdala in humans. In Tac4-/- mice of both sexes, stress-induced mechanical, but not cold hyperalgesia was significantly decreased compared to WTs. Stress-induced behavioral alterations were mild or absent in male WT animals, while significant changes of these parameters could be detected in females. Thymus weight decrease can be observed in both sexes. Higher baseline anxiety and depression-like behaviors were detected in male but not in female HK-1-deficient mice, highlighting the importance of investigating both sexes in preclinical studies. We provided the first evidence for the potent nociceptive and stress regulating effects of HK-1 in chronic restraint stress paradigm. Identification of its targets might open new perspectives for therapy of stress-induced pain.

A Manifesto in Defense of Pain Complexity: A Critical Review of Essential Insights in Pain Neuroscience

Chronic pain has increasingly become a significant health challenge, not just as a symptomatic manifestation but also as a pathological condition with profound socioeconomic implications. Despite the expansion of medical interventions, the prevalence of chronic pain remains remarkably persistent, prompting a turn towards non-pharmacological treatments, such as therapeutic education, exercise, and cognitive-behavioral therapy. With the advent of cognitive neuroscience, pain is often presented as a primary output derived from the brain, aligning with Engel's Biopsychosocial Model that views disease not solely from a biological perspective but also considering psychological and social factors. This paradigm shift brings forward potential misconceptions and over-simplifications. The current review delves into the intricacies of nociception and pain perception. It questions long-standing beliefs like the cerebral-centric view of pain, the forgotten role of the peripheral nervous system in pain chronification, misconceptions around central sensitization syndromes, the controversy about the existence of a dedicated pain neuromatrix, the consciousness of the pain experience, and the possible oversight of factors beyond the nervous system. In re-evaluating these aspects, the review emphasizes the critical need for understanding the complexity of pain, urging the scientific and clinical community to move beyond reductionist perspectives and consider the multifaceted nature of this phenomenon.

Chronic abdominal pain in inflammatory bowel disease: a practical guide

Pain is common in inflammatory bowel disease (IBD), yet many patients feel their pain is not addressed by healthcare professionals. Listening to a patient's concerns about pain, assessing symptoms and acknowledging the impact these have on daily life remain crucial steps in addressing pain in IBD. While acute pain may be effectively controlled by pain medication, chronic pain is more complex and often pharmacological therapies, particularly opioids, are ineffective. Low-dose tricyclic antidepressants and psychological approaches, including cognitive-behavioural therapy, have shown some promise in offering effective pain management while lifestyle changes such as a trial of low-fermentable oligosaccharides, disaccharides, monosaccharides and polyols diet in those with overlapping irritable bowel syndrome may also reduce pain. Patients benefit from a long-term, trusting relationship with their healthcare professional to allow a holistic approach combining pharmacological, psychological, lifestyle and dietary approaches to chronic pain. We present a practical review to facilitate management of chronic abdominal pain in IBD.

Rat Grimace Scale as a Method to Evaluate Animal Welfare, Nociception, and Quality of the Euthanasia Method of Wistar Rats

Refinement of experimental procedures in animal research has the objective of preventing and minimizing pain/distress in animals, including the euthanasia period. This study aimed to evaluate pain associated with six methods of euthanasia in Wistar rats (injectable, inhalational, and physical), by applying the Rat Grimace Scale (RGS), comparing the scores, and determining the method with the highest score that might indicate pain for laboratory rodents. Sixty adult male and female Wistar rats were used and assigned to six treatments: pentobarbital, CO2, decapitation, isoflurane, ketamine + xylazine, and ketamine + CO2. Video recording to assess the RGS scores was performed in four events: basal: 24 h before the procedure; Ti1: three minutes before the procedure; Ti2: during the application of the euthanasia method; and Ti3: immediately after the application until LORR. The main findings of this study showed that, during Ti2, decapitation and ketamine + xylazine had the highest scores (0.6 ± 0.26 and 0.6 ± 0.16, respectively) (p < 0.0001), while at Ti3, CO2 (0.9 ± 0.18) and isoflurane (1.2 ± 0.20) recorded the highest scores (p < 0.0001). According to the present results, decapitation and ketamine + xylazine elicited short-term acute pain, possibly due to tissue damage caused by both methods (injection and guillotine). In contrast, isoflurane's RGS scores recorded during Ti3 might be associated with nociception/pain due to the pungency of the drug or to the pharmacological muscle relaxant effect of isoflurane. Further research is needed to establish a comprehensive study of pain during euthanasia, where RGS could be used minding the limitations that anesthetics might have on facial expression.

The Hidden Toll of Incarceration: Exploring the Link Between Incarceration Histories and Pain Among Older Adults in the United States

Background and Objectives

Incarceration is linked to poor health outcomes across the life course. However, little is known whether and to what extent incarceration histories shape pain in later life. This study examines the relationships between incarceration histories and pain outcomes among middle-aged and older adults in the United States.

Research Design and Methods

Data from a nationally representative sample of community-dwelling adults aged 51 and over in the 2012-2018 biennial waves of the U.S. Health and Retirement Study was analyzed to examine how incarceration histories influence older adults' risks of reporting moderate-to-severe pain and pain with physical limitations. We relied on a propensity score matching approach to account for the potential confounding bias. We fit weighted generalized estimating equation models to assess the relationships between incarceration history and pain outcomes. Models were further stratified by gender.

Results

After propensity score matching, our sample included 2,516 respondents aged 65 years on average (SD = 8.72), 21% female, and 838 with incarceration histories. Persons with incarceration histories have a greater risk of reporting moderate-to-severe pain (prevalence ratio [PR] = 1.30, 95% confidence Interval [CI]: 1.20, 1.52) and pain with physical limitations (PR = 1.48, 95% CI: 1.30, 1.68) even after adjusting for sociodemographic covariates and early life experiences. In the models stratified by gender, the associations between incarceration histories and incarceration were similar among women and men.

Discussion and Implications

In a nationally representative sample of older adults (with or without incarceration history), our study demonstrates an independent association between a history of incarceration and pain in later life. Our findings highlight the far-reaching impact of incarceration and the need for developing optimal management strategies to reduce the burden of disabling pain. Interventions should prioritize socioeconomically vulnerable groups who may have the least access to pain treatment in later life.

Effect of stress on contextual pain sensitivity in the preoperative period- A proof of concept study

Background and Aims

The importance of non-noxious contextual inputs in the interplay of pain with neurophysiologic and behavioral factors is gaining recognition. Stress of impending surgery can act as a negative context, leading to a decrease in pain threshold in patients. This study was conducted to assess the influence of stress conferred by the imminent and other contextual inputs such as anxiety, socioeconomic status, prior painful experience, and the effect of gender on modulation of pain perception in patients undergoing elective surgery.

Material and Methods

In total, 120 patients aged between 18 and 60 years of either gender posted for elective gastrointestinal surgery under general anesthesia were recruited. Data were collected on preoperative anxiety level, socioeconomic status, education, and any prior painful experience. A pressure algometer was used to measure the pressure pain thresholds and pain tolerance on the day before surgery and on the morning of surgery in the preoperative suite.

Results

There was a statistically significant decrease in both pain threshold (P < 0.0001) and pain tolerance in the immediate preoperative period in comparison to the baseline readings taken the day before surgery (P = 0.048). The magnitude of change in pain scalars was greater in females (P < 0.001), those with a high anxiety score, and a history of severe painful experience in the past.

Conclusion

Preoperative surgical stress lowers the pain threshold and pain tolerance. Contextual modulation of pain by factors such as anxiety and memory of prior painful experience, especially in the female gender, could influence postoperative patient outcomes and warrants further research.

Defining Personas of People Living with Chronic Pain: An Ethnographic Research Study

Introduction

Pain is the leading reason for which people seek medical care in the United States, and chronic pain (CP) affects approximately 50 million people in the US Pain perception is deeply personal, is highly correlated with behavioral and emotional disorders, and is greatly influenced by physiological and environmental factors. The patient-provider relationship can have profound implications for clinical outcomes within the context of treating CP. However, limited access to pain specialists, the complex nature of many CP-causing conditions, the absence of instruments for objective pain measurement, and the need to foster a trust-based patient-provider relationship throughout treatment pose unique challenges.

Objective

To support a more optimal CP care delivery system that leverages a healthy therapeutic patient-provider relationship, we systematically gathered deeper knowledge of the behaviors, interpersonal dynamics, home environment, values, and mindsets of people who experience CP.

Methods

We employed ethnographic research methods to collect and analyze data on views, habits, strategies, attitudes, and life circumstances of a range of participants living with CP. We aggregated, analyzed, and summarized participant data to identify trends and similarities.

Results

Our findings suggest that patients can be broadly categorized into five predominant pain typologies, or "personas", which are characterized by respective symptom durations, care management preferences, values, communication styles, and behaviors.

Conclusion

Identifying CP personas may enhance the ability to personalize CP care and help foster more robust therapeutic relationships, which may lead to greater trust, improved patient satisfaction, and better clinical outcomes.

Chiropractic management of bilateral meralgia paresthetica: a case report

Objective

The purpose of this report is to describe the course of chiropractic care for an adult male experiencing persistent anterolateral thigh pain due to bilateral meralgia paresthetica.

Clinical features

A 40-year-old male U.S. Veteran was referred to chiropractic care for a two-year history of bilateral anterolateral thigh pain and paresthesia that worsened with inguinal pressure and hip extension activities.

Intervention and outcomes

A total of six chiropractic visits, including a combination of telehealth and in-person appointments, took place over a period of 10 weeks. Treatments included patient education, soft-tissue therapy, therapeutic exercise prescription, and spinal manipulation directed toward the lumbar spine. The patient's pain was reduced from a 6/10 rating to a 0/10, he was able to reengage in recreational activities without discomfort, and sustained improvement was reported.

Summary

In this case, a trial of chiropractic care was associated with a resolution of the patient's bilateral meralgia paresthetica symptoms.