Pain and emotion: new research directions

Psychosocial influences on pain in transgender individuals

Pain is an unpleasant and unavoidable part of the human experience, but the prevalence and impact of pain disproportionately impacts marginalized groups, including transgender and gender-diverse people. While there are many bases of pain, psychosocial variables, including cognitions (e.g., outcome and interpersonal expectations, social gender norms), affect (e.g., negative affectivity, emotional distress), and social factors (e.g., social exclusion) may be particularly relevant in the pain experiences of transgender individuals. The coalescence of these factors is discussed in this review, where authors specifically consider how these cognitive, affective, and social factors may contribute to pain disparities seen in transgender individuals. Patient-centered communication is presented as a potential avenue to directly mitigate the effect of these psychosocial variables on pain in transgender individuals by reducing feelings of social exclusion transgender patients may experience in the medical office, and the authors call for additional experimental research and the development of educational interventions for providers.

The Impact of Stressful Life Events on Centralized Pain and Pain Intensity: A Combined Model Examining the Mediating Roles of Anger and Perceived Injustice Among Racially Minoritized Adults With Chronic Pain

Stressful life events are highly associated with chronic pain. Yet, research is needed to identify the psychological mechanisms that link life adversity and pain, especially studies that test comprehensive models, recruit racially diverse samples, and measure varied pain-related symptoms. This study examined the relationship between stressful life events and pain in a racially diverse sample and tested the potential mediating roles of both anger and perceived injustice. Both centralized pain symptoms and pain intensity were the outcomes. Analyses consisted of 2 cross-sectional, mediation models among 673 adults with self-reported chronic pain who were racially diverse (Black: n = 258, Latine: n = 254, Asian American: n = 161). The results indicated a positive relationship between stressful life events and centralized pain symptoms (b = 2.53, P < .001) and pain intensity (b = .20, P < .001). In parallel mediation analyses, anger (b = .91, 95% CI = .67, 1.17) and perceived injustice (b = .86, 95% CI = .64, 1.11) acted as partial mediators on centralized pain symptoms. Also, anger (b = .05, 95% CI = .03, .08) and perceived injustice (b = .11, 95% CI = .08, .14) acted as full mediators on pain intensity. The combined psychosocial variables accounted for 51% of centralized pain symptoms and 26% of pain intensity. The findings suggest that psychosocial factors are significantly associated with pain outcomes. Future research is needed to investigate exposure to adversity in life, anger, and perceived injustice together as psychosocial mechanisms of pain symptoms. PERSPECTIVE: Among racially minoritized adults with chronic pain, this article presents empirical evidence that stressful life events, anger, and perceived injustice are associated with centralized pain symptoms and pain intensity. This could guide psychological intervention to focus on anger and perceived injustice, especially when addressing centralized pain.

The efficacy of socially assistive robots in improving children's pain and negative affectivity during needle-based invasive treatment: A systematic review and meta-analysis

BACKGROUND

The ability of socially assistive robots (SARs) to treat dementia and Alzheimer's disease has been verified. Currently, to increase the range of their application, there is an increasing amount of interest in using SARs to relieve pain and negative emotions among children in routine medical settings. However, there is little consensus regarding the use of these robots.

OBJECTIVE

This study aimed to evaluate the effect of SARs on pain and negative affectivity among children undergoing invasive needle-based procedures.

DESIGN

This study was a systematic review and meta-analysis of randomized controlled trials that was conducted in accordance with the Cochrane Handbook guidelines.

METHODS

The PubMed, CINAHL, Web of Science, Cochrane Library, Embase, CNKI, and WanFang databases were searched from inception to January 2024 to identify relevant randomized controlled trials (RCTs). We used the Cochrane Risk of Bias tool 2.0 (RoB2.0) to assess the risk of bias among the included studies, and we used RevMan 5.4 software to conduct the meta-analysis. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) framework was used to assess the quality of the evidence.

RESULTS

Ten RCTs involving 815 pediatric subjects were selected for this review and reported outcomes related to pain and emotions during IV placement, port needle insertion, flu vaccination, blood sampling, and dental treatment. Children undergoing needle-related procedures with SARs reported less anxiety (SMD= -0.36; 95% CI= -0.64, -0.09) and fewer distressed avoidance behaviors (SMD= -0.67; 95% CI= -1.04, -0.30) than did those receiving typical care. There were nonsignificant differences between these groups in terms of in pain (SMD = -0.02; 95% CI = - 0.81, 0.78) and fear (SMD = 0.38; 95% CI= -0.06, 0.82). The results of exploratory subgroup analyses revealed no statistically significant differences based on the intervention type of robots or anesthetic use.

CONCLUSIONS

The use of SARs is a promising intervention method for alleviating anxiety and distress among children undergoing needle-related procedures. However, additional high-quality randomized controlled trials are needed to further validate these conclusions.

TRIAL REGISTRATION

The protocol of this study has been registered in the database PROSPERO (registration ID: CRD42023413279).

Neural dynamics of pain modulation by emotional valence

Definitions of human pain acknowledge at least two dimensions of pain, affective and sensory, described as separable and thus potentially differentially modifiable. Using electroencephalography, we investigated perceptual and neural changes of emotional pain modulation in healthy individuals. Painful electrical stimuli were applied after presentation of priming emotional pictures (negative, neutral, positive) and followed by pain intensity and unpleasantness ratings. We found that perceptual and neural event-related potential responses to painful stimulation were significantly modulated by emotional valence. Specifically, pain unpleasantness but not pain intensity ratings were increased when pain was preceded by negative compared to neutral or positive pictures. Amplitudes of N2 were higher when pain was preceded by neutral compared to negative and positive pictures, and P2 amplitudes were higher for negative compared to neutral and positive pictures. In addition, a hierarchical regression analysis revealed that P2 alone and not N2, predicted pain perception. Finally, source analysis showed the anterior cingulate cortex and the thalamus as main spatial clusters accounting for the neural changes in pain processing. These findings provide evidence for a separation of the sensory and affective dimensions of pain and open new perspectives for mechanisms of pain modulation.

The relationship between emotion regulation and pain catastrophizing in patients with chronic pain

OBJECTIVES

Pain catastrophizing (PC) is a cognitive/emotional response to and in anticipation of pain that can be maladaptive, further exacerbating pain and difficulty in emotion regulation (ER). There is a lack of research on the interplay between PC and ER and its impact on pain. Our aim was to investigate whether ER exacerbated the pain experience through PC.

METHODS

Adults with chronic non-cancer pain of >3 months' duration (n = 150) who were taking opioid medication were recruited from a large medical center in Pennsylvania. A battery of questionnaires was conducted to gather data on demographics, substance use, mental health histories, and health and pain outcomes. Measures used included the 18-Item Difficulties in Emotion Regulation Scale, the Pain Catastrophizing Scale, the Brief Pain Inventory-Short Form, and the Hospital Anxiety and Depression Scale. A structural equation model with latent variables was conducted to examine our aim.

RESULTS

Both pain interference and severity were significantly positively associated with several psychosocial variables, such as anxiety, depression, ER constructs, PC, and distress intolerance. The associations between subscales and pain interference were larger than the associations between subscales and pain severity. PC fully mediated the paths from ER to pain experiences.

DISCUSSION

Our results highlight the importance of several cognitive and emotional constructs: nonacceptance of negative emotions, lack of emotional awareness, magnification of the pain experience, and a sense of helplessness. Furthermore, by showing the indirect effects of PC in affecting ER and pain, we posit that ER, mediated by PC, might serve a critical role in influencing the pain experience in patients with chronic pain.

The effect of experimental emotion induction on experimental pain: a systematic review and meta-analysis

ABSTRACT

The idea that emotions can influence pain is generally recognized. However, a synthesis of the numerous individual experimental studies on this subject is lacking. The aim of the present systematic review and meta-analysis was to synthesize the existing evidence on the effect of experimental emotion induction on experimental pain in nonclinical adults. PsycInfo and PubMed were searched up until April 10, 2023, for studies assessing differences in self-reported pain between emotion induction groups and/or control groups or between conditions within group. Risk of bias was assessed for the individual studies. The literature search yielded 78 relevant records of 71 independent studies. When compared with control conditions, the pooled results revealed a statistically significant pain-attenuating effect of positive emotion induction (between-group: Hedges g = -0.48, 95% CI: -0.72; -0.25, K = 9; within-group: g = -0.24, 95% CI: -0.32; -0.15, K = 40), and a statistically significant pain-exacerbating effect of negative emotion induction in within-group analyses but not between-group analyses (between-group: g = -0.29, 95% CI: -0.66; 0.07, K = 10; within-group: g = 0.14, 95% CI: 0.06; 0.23, K = 39). Bayesian meta-analysis provided strong support for an effect of positive emotion induction but weak support for an effect of negative emotion induction. Taken together, the findings indicate a pain-attenuating effect of positive emotion induction, while the findings for negative emotion induction are less clear. The findings are discussed with reference to theoretical work emphasizing the role of motivational systems and distraction for pain. Limitations include considerable heterogeneity across studies limiting the generalizability of the findings.

The Predictive Value of Cold Pack Test for Pain After Third Molar Surgery

BACKGROUND

Early identification of patients who are prone to postoperative pain may provide individualization of postoperative analgesia strategies.

PURPOSE

The aim of the study was to investigate whether the cold pack test is associated with postoperative pain levels after mandibular third molar surgery.

STUDY DESIGN, SETTING, SAMPLE

This prospective cohort study included healthy male patients admitted to Department of Oral and Maxillofacial Surgery of a tertiary health-care center between June 2022 and December 2022 and scheduled for lower third molar extraction. Those who had used any analgesic within the past 10 days or had a history of intolerance/allergy to analgesics were excluded.

PREDICTOR VARIABLE

The primary predictor variable was pain tolerance, measured using the endurance test score. Subjects were grouped into two categories, low tolerance test score (withdrew the hand from the cold pack in <240 seconds) and high tolerance test score (maintained the hand on the cold pack for 240 seconds).

MAIN OUTCOME VARIABLES

The primary outcome variable was pain measured by the patients from 0 to 10 with the visual analog scale, and the secondary outcome variables were the amount of ibuprofen and paracetamol consumed in the postoperative period. Pain measurements and ibuprofen consumption were recorded at 0-2, 8, 16, 24, 32, 40, 48, 56, 64, 72, 80, 88, and 96 hours (0-2 interval of the first 2 hours immediately after surgery).

COVARIATES

Age, classification and position of mandibular third molar were utilized as covariates.

ANALYSES

The relationship between pain tolerance and postoperative pain was analyzed using the Mann-Whitney U test and the Fisher exact test. Statistical analysis was performed using the SPSS version 28.0 software.

RESULTS

A total of 30 male patients with a mean age of 22.5 ± 4.8 years were included in our study. In the group with low pain tolerance, the pain scores at the first 2 hours, 32, and 48 hours after the operation (4.55 ± 3.59, 2.91 ± 2.59, 2.91 ± 2.43, respectively) were found to be significantly higher than the group with high pain tolerance (2.00 ± 2.67, 0.95 ± 1.68, 0.95 ± 1.39, respectively) (P < .05). In the first 2 hours after the operation, the amount of ibuprofen consumed was also significantly higher in the group with low pain tolerance compared to the other group, and 81.8% of this group felt the need to consume ibuprofen (P < .05).

CONCLUSIONS AND RELEVANCE

The cold pack test, a more practical version of quantitative sensory testing, is useful in identifying male patients at risk of developing greater pain after third molar surgery. It can be helpful to provide effective analgesia in male patients with different pain tolerance thresholds.

Transcriptome-wide analysis of trigeminal ganglion and subnucleus caudalis in a mouse model of chronic constriction injury-induced trigeminal neuralgia

Trigeminal neuropathic pain (TNP) induces mechanical allodynia and hyperalgesia, which are known to alter gene expression in injured dorsal root ganglia primary sensory neurons. Non-coding RNAs (ncRNAs) have been linked to TNP. However, the functional mechanism underlying TNP and the expression profile of ncRNAs in the trigeminal ganglion (TG) and trigeminal subnucleus caudalis (Sp5C) are still unknown. We used RNA sequencing and bioinformatics analysis to examine the TG and Sp5C transcriptomes after infraorbital nerve chronic constrictive injury (IoN-CCI). The robust changes in the gene expression of lncRNAs, circRNAs, and mRNAs were observed within the TG and Sp5C from mice that underwent IoN-CCI and the sham-operated mice (day 7). In total, 111,003 lncRNAs were found in TG and 107,157 in Sp5C; 369 lncRNAs were differentially expressed in TG, and 279 lncRNAs were differentially expressed in Sp5C. In addition, 13,216 circRNAs in TG and 21,658 circRNAs in Sp5C were identified, with 1,155 circRNAs and 2,097 circRNAs differentially expressed in TG and Sp5C, respectively. Furthermore, 5,205 DE mRNAs in TG and 3,934 DE mRNAs in Sp5C were differentially expressed between IoN-CCI and sham groups. The study revealed a high correlation of pain-related differentially expressed genes in the TG and Sp5C to anxiety, depression, inflammation, neuroinflammation, and apoptosis. Gene Ontology analysis revealed that binding-related molecular functions and membrane-related cell components were significantly enriched. Kyoto Encyclopedia of Genes and Genomes analysis shows the most significant enrichments in neurogenesis, nervous system development, neuron differentiation, adrenergic signaling, cAMP signaling, MAPK signaling, and PI3K-Akt signaling pathways. Furthermore, protein-protein interaction analysis showed that hub genes were implicated in neuropeptide signaling pathways. Functional analysis of DE ncRNA-targeting genes was mostly enriched with nociception-related signaling pathways underpinning TNP. Our findings suggest that ncRNAs are involved in TNP development and open new avenues for research and treatment.

Feasibility, Acceptability, and Preliminary Efficacy of a Positive Affect Skills Intervention for Adults With Fibromyalgia

Background and Objectives

To examine the feasibility, acceptability, and preliminary efficacy of a positive affect skills intervention for middle-aged and older adults with fibromyalgia syndrome (FMS).

Research Design and Methods

Ninety-five participants with FMS aged 50 and older (94% female) were randomized to 1 of 2 conditions: (a) Lessons in Affect Regulation to Keep Stress and Pain UndeR control (LARKSPUR; n = 49) or (b) emotion reporting/control (n = 46). LARKSPUR included 5 weeks of skill training that targeted 8 skills to help foster positive affect, including (a) noticing positive events, (b) savoring positive events, (c) identifying personal strengths, (d) behavioral activation to set and work toward attainable goals, (e) mindfulness, (f) positive reappraisal, (g) gratitude, and (h) acts of kindness. Outcome data were collected via online surveys at baseline, postintervention, and 1-month follow-up.

Results

Completion rates (88%) and satisfaction ratings (10-point scale) were high (LARKSPUR: M = 9.14, standard deviation (SD) = 1.49; control: M = 8.59, SD = 1.97). Improvements were greater in LARKSPUR participants compared with control participants on measures of positive affect (Cohen's d = 0.19 [0.15, 0.24]), negative affect (Cohen's d = -0.07 [-0.11, -0.02]), and pain catastrophizing (Cohen's d = -0.14 [-0.23, -0.05]). Improvements in positive affect (Cohen's d = 0.17 [0.13, 0.22]) and negative affect (Cohen's d = -0.11 [-0.15, -0.06]) were maintained at 1-month follow-up. Dose-response analyses indicated that intervention engagement significantly predicted pre-to-post and post-to-follow-up reductions in pain catastrophizing.

Discussion and Implications

The current preliminary findings add to existing literature and highlight the specific potential of internet-delivered positive affect skills programs for adults with FMS.

Clinical Trial Registration

NCT04869345.

A Review of Voice-Based Pain Detection in Adults Using Artificial Intelligence

Pain is a complex and subjective experience, and traditional methods of pain assessment can be limited by factors such as self-report bias and observer variability. Voice is frequently used to evaluate pain, occasionally in conjunction with other behaviors such as facial gestures. Compared to facial emotions, there is less available evidence linking pain with voice. This literature review synthesizes the current state of research on the use of voice recognition and voice analysis for pain detection in adults, with a specific focus on the role of artificial intelligence (AI) and machine learning (ML) techniques. We describe the previous works on pain recognition using voice and highlight the different approaches to voice as a tool for pain detection, such as a human effect or biosignal. Overall, studies have shown that AI-based voice analysis can be an effective tool for pain detection in adult patients with various types of pain, including chronic and acute pain. We highlight the high accuracy of the ML-based approaches used in studies and their limitations in terms of generalizability due to factors such as the nature of the pain and patient population characteristics. However, there are still potential challenges, such as the need for large datasets and the risk of bias in training models, which warrant further research.

Lessons in Affect Regulation to Keep Stress and Pain UndeR control (LARKSPUR): Design of a randomized controlled trial to increase positive affect in middle-aged and older adults with fibromyalgia

BACKGROUND

Fibromyalgia syndrome (FMS) is a leading cause of functional limitations and disability for which there is no cure. Positive psychological interventions for improving health have received increasing attention, but evidence of the feasibility, acceptability, and impact of such interventions in adult populations with FMS is limited.

OBJECTIVES

To describe the rationale and design of a 5-week, online positive affect skills intervention, LARKSPUR: Lessons in Affect Regulation to Keep Stress and Pain UndeR control.

METHODS

FMS participants (N = 90) will be randomized to one of two conditions: (1) LARKSPUR or (2) emotion reporting/attention control. LARKSPUR is an online multicomponent intervention that targets eight skills to help foster positive affect: (1) noticing positive events, (2) savoring positive events, (3) identifying personal strengths, (4) behavioral activation to set and work toward attainable goals, (5) mindfulness, (6) positive reappraisal, (7) gratitude, and (8) acts of kindness. The primary outcomes include feasibility (i.e., recruitment, retention, adherence) and acceptability (i.e., helpfulness, usability, satisfaction). Secondary outcomes include pain intensity and pain interference.

SIGNIFICANCE

If feasibility and acceptability metrics are met and reductions in pain outcomes are achieved, we will undertake future efficacy and effectiveness trials of LARKSPUR among older adults with FMS.

TRIAL REGISTRATION

NCT04869345.

Association of Weight-Related Stigmas With Daily Pain Symptoms Among Individuals With Obesity

BACKGROUND

Individuals with obesity are disproportionately impacted by pain-related symptoms.

PURPOSE

This study evaluated experienced weight stigma and internalized weight bias (IWB) as predictors of pain symptoms in daily life among individuals with obesity.

METHODS

Adults with obesity (n = 39; 51% female, 67% White, 43.8 ± 11.6 years old, BMI = 36.8 ± 6.7 kg/m2) completed a baseline assessment (demographics, experienced weight stigma, IWB) and a 14-day Ecological Momentary Assessment (EMA) period involving five daily prompts of pain/aches/joint pain, muscle soreness, experienced weight stigma, and IWB. Generalized linear models were used to assess experienced weight stigma and IWB at baseline as prospective predictors of EMA pain/soreness symptoms. Multi-level models were used to test the association of momentary weight stigma experiences and IWB with pain/soreness at the same and subsequent EMA prompts.

RESULTS

IWB at baseline, but not experienced weight stigma, was associated with more frequent pain symptoms (p < .05) and muscle soreness (p < .01) during EMA. Momentary IWB (but not experienced stigma) was associated with more pain/aches/joint pain and muscle soreness at the same and subsequent prompt.

CONCLUSIONS

Internalized (but not experienced) weight bias was prospectively associated with pain symptoms in daily life among individuals with obesity. Results are consistent with growing evidence that weight-related stigmas represent psychosocial factors that contribute to weight-related morbidity typically attributed to body size.

Fullerene-Filtered Light Spectrum and Fullerenes Modulate Emotional and Pain Processing in Mice

The most symmetric molecule, Buckminster fullerene C60, due to its unique properties, has been intensively studied for various medical and technological advances. Minimally invasive and minimally toxic treatments hold great promise for future applications. With this in mind, this research exploited the physical properties of fullerene molecules for potential therapeutic effects. Pristine fullerenes have peak absorbance in the 380–500 nm range, making them an attractive violet-blue light filter. Since spectral quality of light can affect behavior, this research used resting state functional magnetic resonance imaging (rs fMRI) and behavioral testing to directly evaluate the effects of fullerene-filtered light on brain processing and behavior in mice. The same method was used to study if hydroxyl fullerene water complexes (3HFWC), with or without fullerene-filtered light, modulated brain processing. A month-long, daily exposure to fullerene-filtered light led to decreased activation of the brain area involved in emotional processing (amygdala). Water supplemented with 3HFWC resulted in an activation of brain areas involved in pain modulation and processing (periaqueductal gray), and decreased latency to first reaction when tested with a hot plate. The combination of fullerene-filtered light with 3HFWC in drinking water led to restored sensitivity to a hot plate and activation of brain areas involved in cognitive functions (prelimbic, anterior cingulate and retrosplenial cortex). These results uncovered the potential of fullerene-filtered light to impact emotional processing and modulate pain perception, indicating its further use in stress and pain management.

Heart Rate Variability and Pain Sensitivity in Chronic Low Back Pain Patients Exposed to Passive Viewing of Photographs of Daily Activities

OBJECTIVE

Investigation if emotional reactivity by measuring heart rate variability (HRV) and pressure pain sensitivity during a passive visualization task in participants with chronic low back pain (CLBP).

MATERIALS AND METHODS

This case-control study was composed of 47 participants with CLBP and 47 asymptomatic participants. Both groups were submitted to a passive visualization task using 27 pictures from PHODA (Photograph Series of Daily Activities). HRV frequency domains were measured before, during, and after the task. Pressure pain threshold and pain intensity were also measured before and after the task.

RESULTS

The adjusted mean difference was statistically significant for HRV frequency domains during the visualization task, including low frequency [-5.92; 95% confidence interval (CI)=-9.60 to -2.23], high frequency (-0.71; 95% CI=-1.02 to -0.39), and low-frequency/high-frequency ratio (8.82; 95% CI=5.19 to 12.45). Pressure pain threshold decreased after the task in the CLBP group in all body sites, and pain intensity increased (-0.8; 95% CI=-1.16 to -0.39).

DISCUSSION

Aversive environmental stimuli, such as visual cues, may generate defensive physiological reactions. HRV can provide a measure that reflects the perceptions of threat and safety in the environment. Participants with CLBP presented changes in sympathovagal balance during passive visualization of pictures of daily activities, higher pain sensitivity, and high pain intensity when they were exposed to a passive visualization task using pictures of daily living that may arouse fears of harm.

Applying the NIA Health Disparities Research Framework to Identify Needs and Opportunities in Chronic Musculoskeletal Pain Research

Disparities in the experience of chronic musculoskeletal pain in the United States stem from a confluence of a broad array of factors. Organized within the National Institute on Aging Health Disparity Research Framework, a literature review was completed to evaluate what is known and what is needed to move chronic musculoskeletal pain research forward specific to disproportionately affected populations. Peer-reviewed studies published in English, on human adults, from 2000 to 2019, and conducted in the United States were extracted from PubMed and Web of Science. Articles were reviewed for key words that focused on underrepresented ethnic/race groups with chronic musculoskeletal pain applying health factor terms identified in the NIAHealth Disparity Research Framework four levels of analysis: 1) environmental, 2) sociocultural, 3) behavioral, and 4) biological. A total of 52 articles met inclusion criteria. There were limited publications specific to underrepresented ethnic/race groups with chronic musculoskeletal pain across all levels with particular research gaps under sociocultural and biological categories. Current limitations in evidence may be supplemented by a foundation of findings specific to the broader topic of "chronic pain" which provides guidance for future investigations. Study designs including a focus on protective factors and multiple levels of analyses would be particularly meritorious. PERSPECTIVE: Chronic musculoskeletal pain unequally burdens underrepresented ethnic/race groups. In order to move research forward and to systematically investigate the complex array of factors contributing toward health disparities, an organized approach is necessary. Applying the NIA Health Disparities Research Framework, an overview of the current state of evidence specific to chronic musculoskeletal pain and underrepresented ethnic/race groups is provided with future directions identified.

Emotion regulation and peripheral psychophysiological correlates in the management of induced pain: A systematic review

Cognitive reappraisal and acceptance strategies have been shown to be effective in reducing pain experience and increasing pain tolerance. However, no systematic reviews have focused on the relationship between the use of these two strategies and peripheral physiological correlates when pain is experimentally induced. This systematic review aims to summarize the existing literature that explores the relationship between emotion regulation strategies (i.e., cognitive reappraisal and acceptance) and peripheral correlates of the autonomic nervous system and facial electromyography, such as affect-modulated responses and corrugator activity, on laboratory tasks where pain is induced. The systematic review identifies nine experimental studies that meet our inclusion criteria, none of which compare these strategies. Although cognitive reappraisal and acceptance strategies appear to be associated with decreased psychological responses, mixed results were found for the effects of the use of both strategies on all the physiological correlates. These inconsistencies between the studies might be explained by the high methodological heterogeneity in the task designs, as well as a lack of consistency between the instructions used in the different studies for cognitive reappraisal, acceptance, and the control conditions.

Psychometric Properties of Iranian Version of Emotional Processing Scale

BACKGROUND: Emotional processing scale (EPS) is a fundamental test for measurement of the abnormal processing of emotion and psychosomatic disorders in psychotherapy sessions. Despite its importance, EPS has not been yet translated and validated in the Iranian population. AIM: To fill this gap, this study aims to adapt and examined the psychometric properties of five EPS in the Iranian population. Using cluster sampling, we selected 1283 university students. METHODS: The structural equation modeling and confirmatory factor analysis used to analyze the assessment of validity. RESULTS: The result showed the Cronbach’s alpha, split half, and test re-test reliability in acceptable ranges; 0.91, 0.90, and 0.91, respectively, for total scores scale. Root Mean Square Error of Approximation, Standardized Root Mean Square Residual, goodness of fit, and comparative fit index were at an acceptable range, 0.07, 0.05, 0.90, 0.90, 0.89, and 0.85, respectively. The total scores of EPS also showed a positive correlation (0.63, p < 0.001) with GHQ 28. CONCLUSION: The result suggested that five factors model of EPS which includes: The suppression, sign of unprocessed emotion, unregulated emotion, avoidance, and impoverished emotional experience model fit the data well be most appropriated for Iranian population.

Pain Sensitivity, Negative Affect, and Alcohol Use Disorder Status: A Moderated Mediation Study of Emotion Dysregulation

Previous work suggests that the association between pain and emotional processes among individuals with alcohol use disorder (AUD) may differ from healthy controls. This study investigates whether pain sensitivity mediates the association between negative affect and emotional dysregulation and whether this association differs across AUD status using moderated mediation. The sample included 165 individuals diagnosed with AUD and 110 healthy controls. Of interest was pain sensitivity, as assessed with the Pain Sensitivity Questionnaire, negative affect, as assessed with the Beck Depression Inventory, and emotional dysregulation, as assessed with the Difficulties in Emotional regulation Scale. Age, biological sex, and current pain severity were included as covariates. The results support a moderated partial mediation model that explained 44% of the variance in emotional dysregulation. The findings indicate that negative affect is related to higher pain sensitivity across groups. Moreover, pain sensitivity partially mediated the association between negative affect and emotional dysregulation, but in opposite directions depending on AUD status. Among healthy controls, greater pain sensitivity was related to better emotional regulation, while greater pain sensitivity led to greater emotional dysregulation among individuals with AUD. The potential parallels in the underlying neurobiological mechanisms of emotionality, pain, and AUD suggest that interventions targeting pain may improve adaptive affect regulation skills, which in turn could reduce negative affect and its effect on pain sensitivity among individuals with AUD.

Integrating Lifestyle Focused Approaches into the Management of Primary Dysmenorrhea: Impact on Quality of Life

OBJECTIVE

This narrative review aims to identify alternative ways to improve the symptoms of primary dysmenorrhea (PD).

BACKGROUND

PD refers to endometrial painful cramps during the premenstrual period. This condition affects a lot of women worldwide and is accompanied with absenteeism and high economic costs, thus, risk-free, and effective therapeutic approaches are needed. Pharmacological agents such as non-steroidal anti-inflammatory drugs (NSAIDs) and oral contraceptive pills (OCPs), which are widely prescribed for these women, demonstrate adequate efficacy in alleviating pain and discomfort. The long natural course of the disease dictates remedies that focus on lifestyle changes and on improvement of Quality-of-Life (QoL) for women suffering with PD.

MATERIALS AND METHODS

Five major search engines, namely MEDLINE, PubMed, EMBASE, and Cochrane Library were searched for articles published prior to October 2020 focused in PD. A total of 74 paper were included.

DISCUSSION

Physical activity, for instance yoga, aromatherapy massage, and other forms of relaxation, vitamins and dietary changes, acupressure and acupuncture,a and some psychological interventions are just few of the proposed health behavior targeted approaches in cases of PD. This review focuses on lifestyle changes and alternative methods that could potentially result in minimizing symptoms of PD and in improving overall QoL for these patients, by providing current scientific evidence on their efficacy.

CONCLUSION

Complementary and alternative medicine practices (CAM) are widely accepted by women. International literature provides controversial scientific evidence, thus further studies need to be conducted in order to prove or disregard their efficacy in cases of PD.

Pain and Stress Detection Using Wearable Sensors and Devices-A Review

Pain is a subjective feeling; it is a sensation that every human being must have experienced all their life. Yet, its mechanism and the way to immune to it is still a question to be answered. This review presents the mechanism and correlation of pain and stress, their assessment and detection approach with medical devices and wearable sensors. Various physiological signals (i.e., heart activity, brain activity, muscle activity, electrodermal activity, respiratory, blood volume pulse, skin temperature) and behavioral signals are organized for wearables sensors detection. By reviewing the wearable sensors used in the healthcare domain, we hope to find a way for wearable healthcare-monitoring system to be applied on pain and stress detection. Since pain leads to multiple consequences or symptoms such as muscle tension and depression that are stress related, there is a chance to find a new approach for chronic pain detection using daily life sensors or devices. Then by integrating modern computing techniques, there is a chance to handle pain and stress management issue.

Individual differences in momentary pain-affect coupling and their associations with mental health in patients with chronic pain

OBJECTIVE

Pain and affect are generally associated. However, individuals may differ in the magnitude of the coupling between pain and affect, which may have important implications for their mental health. The present study uses ecological momentary assessments (EMA) to examine individual differences in momentary pain-affect coupling and their associations with depressive and anxiety symptoms.

METHODS

This study is a secondary data analysis of three primary EMA studies. Participants were a total of 290 patients with chronic pain. Results were synthesized across studies using meta-analytic techniques.

RESULTS

Individuals whose pain was more strongly concurrently coupled with affect (positively associated with negative affect or negatively associated with positive affect) reported higher levels of depressive and anxiety symptoms. Results from lagged analyses suggest that individual differences in affect reactivity to pain were not significantly associated with depressive or anxiety symptoms.

CONCLUSION

These findings suggest that individuals with greater concurrent coupling between pain and affect experience more mental health problems. Potential avenues for future research include intervention strategies that target the decoupling of pain and affect experiences in patients with chronic pain.

Nonsteroidal Anti-inflammatory Drugs vs Cognitive Behavioral Therapy for Arthritis Pain: A Randomized Withdrawal Trial

IMPORTANCE

Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly prescribed for knee osteoarthritis. However, they are associated with uncertain long-term clinical benefit and significant toxic effects.

OBJECTIVE

To evaluate whether discontinuing NSAIDs and engaging in a telephone-based cognitive behavioral therapy (CBT) program is noninferior to continuing NSAIDs for patients with knee osteoarthritis.

DESIGN, SETTING, AND PARTICIPANTS

The Stopping NSAIDs for Arthritis Pain multicenter randomized withdrawal trial was conducted for 364 patients taking NSAIDs for knee osteoarthritis pain on most days of the week for at least 3 months between September 1, 2013, and September 30, 2018. Analysis was performed on an intent-to-treat basis.

INTERVENTIONS

Participants discontinued their current NSAID and took 15 mg per day of meloxicam daily during a 2-week run-in period. Those who remained eligible were randomized in a 1:1 ratio to receive meloxicam or placebo for 4 weeks (blinded phase 1). Participants receiving meloxicam then continued this medication for 10 weeks, while those receiving placebo participated in a 10-week CBT program (unblinded phase 2).

MAIN OUTCOMES AND MEASURES

The primary outcome measure was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score at 4 weeks with the noninferiority margin set at 1. Secondary outcomes included the area under the curve of the pain score after 4 weeks as well as the WOMAC pain score, area under the curve of the pain score, WOMAC disability score, and global impression of change after treatment at 14 weeks.

RESULTS

A total of 180 participants (161 men; mean [SD] age, 58. 2 [11.8] years) were randomized to receive placebo followed by CBT, and a total of 184 participants (154 men; mean [SD] age, 58.5 [10.0] years) were randomized to receive meloxicam. After adjustment for baseline pain and study site, the estimated mean difference in WOMAC pain score between the placebo and meloxicam groups after 4 weeks was 1.4 (95% CI, 0.8-2.0; noninferiority test P = .92). At week 14, the adjusted mean difference in WOMAC pain score between the placebo (followed by CBT) and meloxicam groups was 0.8 (95% CI, 0.2-1.4; noninferiority P = .28). There was no statistically significant difference in the global impression of change (mean difference in scores, -0.2; 95% CI, -0.4 to 0.1; P = .15) or lower extremity disability (mean difference in scores, 0.9; 95% CI, -1.4 to 3.2; P = .45) between the 2 groups after 14 weeks.

CONCLUSIONS AND RELEVANCE

Among patients with knee osteoarthritis, placebo and CBT (after placebo) are inferior to meloxicam. However, the WOMAC pain score differences between the 2 groups were small, and there were no statistically significant differences in participants' global impression of change or function after 14 weeks.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01799213.

Positive affect and chronic pain: a preregistered systematic review and meta-analysis

Chronic noncancer pain (CNCP) is a significant health burden among adults. Standard behavioral therapies typically focus on targeting negative affect (NA) and yield only modest treatment effects. The aims of this study were to systematically review and investigate the association between positive affect (PA) and pain severity among adults with CNCP. Databases that were searched included MEDLINE (PubMed), PsycINFO, CINAHL, ProQuest Dissertations and Theses, OLASTER, Open Grey, and PsyArXiv (inception to July 23, 2019). We analyzed studies that: (1) used observational, experimental, or intervention study designs; (2) enrolled individuals with CNCP (pain ≥ 12 weeks); and (3) reported full quantitative results on outcomes. Two researchers independently screened articles, extracted data, and assessed the risk of bias. The main meta-analysis was followed by subgroup analyses. All analyses were performed using random-effects models. Formal tests for heterogeneity (Q-statistic; I) and publication bias (p-curve and p-uniform*) were performed. We meta-analyzed 29 studies with 3521 participants. Results demonstrated that PA inversely impacts pain severity in people with CNCP (r = -0.23). Subgroup analyses showed a significant effect for gender and marginally significant effects for age in studies that adjusted for NA. On average, effect sizes for observational studies were larger in studies with a higher proportion of female respondents and in studies that did not adjust for NA. Finally, larger effect sizes were found in intervention studies with older compared with younger samples.

Interpersonal Tensions and Pain Among Older Adults: The Mediating Role of Negative Mood

OBJECTIVES

To examine whether (a) negative social encounters and physical pain are linked throughout the day, (b) negative mood mediates these associations, and (c) these associations vary by closeness with social partners.

METHOD

Adults aged 65+ (n = 313) completed ecological momentary assessments and reported their negative social encounters, physical pain, and mood every 3 hr throughout the day for 5-6 days.

RESULTS

Multilevel models revealed that negative social encounters were associated with greater pain at each 3-hr interval and that this association was mediated by negative mood during the same interval. Negative encounters with less close partners were associated with pain, but negative encounters with close partners were not.

DISCUSSION

Regulating older adults' negative emotions may be crucial to improving their daily pain. Further, interventions focusing on negative encounters with less close partners in daily life may help mitigate older adults' experiences of pain throughout the day.

Back pain occurrence and treatment-seeking behavior among nurses: the role of work-related emotional burden

PURPOSE

To assess the association of back pain and treatment-seeking behavior for such pain with work-related emotional burden (regret about care), regret coping strategies, and physical burden among newly practicing nurses.

METHODS

We used data from the Impact of Care-related Regret Upon Sleep (ICARUS) cohort collected between 05.2017 and 07.2018 using web-based surveys (weekly for measures of emotional burden, physical burden and coping strategies, and monthly for back pain and seeking care). We investigated immediate associations and temporal influences between burdens and back pain with linear mixed models and cross-lagged Bayesian models, respectively. Coefficients were standardized to allow comparison between burdens. Logistic regression was used to examine the association of burdens with seeking care.

RESULTS

Among 105 nurses with an average follow-up of 3 months, 80 reported at least one episode of back pain. Neither physical nor emotional burdens had an immediate association with back pain. However, number of days with back pain in a given month was associated with an increase in both burdens during the previous month, with similar degrees of association (emotional: b = 0.24, physical: b = 0.21). Decision to seek treatment was associated with an increase in back pain frequency (OR 1.12, p = 0.04) and intensity (OR 1.80, p = 0.002) and a decrease in emotional burden (OR 0.95, p = 0.03). Coping strategies were associated neither with the occurrence of back pain nor with care-seeking.

CONCLUSION

While both emotional and physical burdens were associated with increased frequency of back pain the following month, emotional burden additionally showed a negative association with the decision to seek care.

Vocal Music Therapy for Chronic Pain: A Mixed Methods Feasibility Study

Objective: The purpose of this study was to determine the feasibility and preliminary effects of a vocal music therapy (VMT) program on chronic pain management.

Design: A mixed methods intervention design was used in which qualitative data were embedded within a randomized controlled trial.

Setting: An urban nurse-management health center on the East Coast of the United States.

Subjects: Participants (N = 43) were predominantly Black (79%) and female (76.7%) with an average pain duration of 10 years.

Intervention: Participants were randomly allocated to a 12-week VMT program or a waitlist control.

Outcome measures: We tracked consent rate (percentage of participants enrolled out of total number screened), attrition rate, and treatment adherence. We used PROMIS^® (Patient Reported Outcomes Measurement Information System) tools to measure pain interference, pain-related self-efficacy, pain intensity, depression, anxiety, positive effect, and well-being, ability to participate in social activities, and satisfaction with social roles at baseline and week 12. VMT participants also completed the Patient Global Impression of Change Scale. We conducted semistructured interviews to better understand participants' experience of the intervention.

Results: The consent rate was 56%. The attrition rate was 23%. Large treatment effects (partial eta squared) were obtained for self-efficacy (0.20), depression (0.26), and ability to participate in social activities (0.24). Medium effects were found for pain intensity (0.10), anxiety (0.06), positive effect, and well-being (0.06), and small effects for pain interference (0.03) and satisfaction with social roles (0.03). On average, participants felt moderately better after completion of the VMT program (M = 4.93, standard deviation = 1.98). Qualitative findings suggest that VMT resulted in better self-management of pain, enhanced psychological well-being, and stronger social and spiritual connections.

Conclusions: Recruitment into the 12-week program was challenging, but quantitative and qualitative findings suggest significant benefits of VMT for chronic pain management.

Global Versus Momentary Osteoarthritis Pain and Emotional Distress: Emotional Intelligence as Moderator

Background

Pain and emotional well-being are complexly associated both globally and in the moment. Emotional regulation strategies may contribute to that complexity by shaping the pain-well-being association.

Purpose

Using emotional intelligence (EI) as an integrative conceptual framework, this study probed the role of emotional regulation in the associations of osteoarthritis pain with emotional well-being in varying time frames. Perceived attention to, clarity, and regulation of emotions were examined as predictors of well-being, and as moderators of the well-being-pain association, at global and momentary (within-day) levels.

Methods

In a microlongitudinal study, 218 older adults with physician-diagnosed knee osteoarthritis self-reported global pain, depressive symptoms, and EI (mood attention, clarity, and repair). Momentary pain and positive and negative affect were then assessed four times daily for 7 days. EI subscales were examined as moderators of the pain-well-being association at global and momentary levels, controlling demographics and general health.

Results

Global and momentary pain were positively associated with mood clarity and negatively with attention, but not with repair. Clarity and repair negatively predicted depression, and buffered effects of pain on depression. Momentary negative affect was negatively predicted by mood clarity and repair; again, clarity and mood repair buffered effects of momentary pain on negative affect. Only mood repair predicted positive affect, with no interactions emerging.

Conclusions

Attention to mood states exacerbates the experience of pain in both short and long terms. In contrast, both mood clarity and ability to repair moods appear important to both momentary and longer-term emotional well-being.

Economic Impact of Headache and Psychiatric Comorbidities on Healthcare Expenditures Among Children in the United States: A Retrospective Cross-Sectional Study

OBJECTIVE

To examine the annual healthcare expenditures associated with childhood headache in the United States, and to evaluate whether psychiatric comorbidities increase the impact of headache on expenditures.

BACKGROUND

Headache is prevalent in childhood and co-occurs with anxiety disorders, depressive disorders, and attention deficit/hyperactivity disorder (ADHD), which may increase cost of illness.

METHODS

We conducted a secondary data analysis using a nationally representative sample of 34,633 children ages 2-17 from the 2012-2015 Medical Expenditure Panel Surveys (MEPS), of which 779 (weighted 2.6%) were identified as having headache based on health service use associated with headache. Using a comprehensive cost-of-illness approach, we assessed the incremental expenditures associated with headache and determined excess expenditures associated with psychiatric comorbidities using standard adjusted 2-part expenditure models.

RESULTS

Annual total healthcare expenditures were estimated to be 24.3% higher, 95% CI [1,55], in our headache group ($3036, 95% CI [2374,3699] vs $2350, 95% CI [2140,2559]). Total national expenditures associated with pediatric headache in the United States were estimated at $1.1 billion annually, 95% CI [.04, 2.2 billion]. Depression and ADHD were associated with higher incremental expenditures for the headache group (depression: $1815, 95% CI[676,2953] vs $1409, 95% CI[697,2112]; ADHD: $4742, 95% CI[1659,7825] vs $2935, 95% CI[1977,3894]); however, interactions between psychiatric comorbidities and headache did not reach statistical significance.

CONCLUSION

Youth with headache exert a considerable economic burden on families, healthcare systems, and society. Due to the limitations in methods used to classify youth with headache in MEPS, our findings may underestimate the true prevalence and cost of pediatric headache in the United States. Further research with larger sample sizes is needed to understand the impact of psychiatric comorbidities on healthcare expenditures in this population.

The Impact of Emotional Regulation Strategies on Pain Catastrophizing in the Context of Interpersonal Relationships

OBJECTIVES

The Communal Coping Model suggests that pain catastrophizing may serve to elicit support from others. What is not known is how emotional regulation, namely emotional inhibition, impacts pain catastrophizing within the context of an interpersonal relationship. Individuals who have a greater tendency to emotionally inhibit may have a greater likelihood to use catastrophizing as a means for seeking support, particularly in relationships characterized by satisfaction and emotional validation.

METHODS

Data were collected from 50 undergraduate couples at the University of Michigan-Dearborn. Participants were videotaped during the completion of an acute pain cold pressor task and completed measures involving pain catastrophizing, emotional inhibition, and relationship dynamics (ie, Ambivalence Over Emotional Expressiveness Questionnaire, White Bear Suppression Inventory, Dyadic Adjustment Scale). In addition, the videotaped interactions were coded for both invalidation/validation and overt expressions of pain catastrophizing.

RESULTS

Emotional inhibition, and both validation and invalidation were associated with pain catastrophizing. Observed validation and invalidation were not, however, directly associated with relationship satisfaction. Hierarchical linear regression showed a significant interaction between thought suppression and relationship satisfaction to predict pain catastrophizing.

DISCUSSION

Results show relationship satisfaction moderates the association between pain catastrophizing and thought suppression in a manner in which couples with high levels of relationship satisfaction who also engage in thought suppression are more likely to use pain catastrophizing as a cognitive strategy to elicit support. This study offers direction into treatment and suggests that couples based cognitive-behavioral treatments that aim to utilize adaptive cognitive and behavioral coping strategies, as well as emotional exploration and validation, may be beneficial.

Intra- and interindividual differences in the within-person coupling between daily pain and affect of older adults

The bidirectional interplay between chronic pain and negative affect is well-established in patient samples. However, less is known about the day-to-day relationship between pain and affect of older adults without severe illnesses and to what extent this association differs within and between individuals. A total of 224 participants (M_age = 77.6, SD_age = 6.2) reported their daily experience of pain, impairment by their pain and affect during 21 consecutive days. Multilevel modeling results showed that on days with increased pain individuals also reported less positive affect and more negative affect. Time-lagged results indicated a temporal carry-over from yesterday's pain to today's negative affect but not to today's positive affect. Moreover, on days when individuals reported stronger impairment by their pain, they showed a stronger within-person coupling between daily pain and affect in contrast to days with a weaker experience of daily impairment. Yesterday's pain and today's negative affect were more strongly associated within individuals who reported higher levels of impairment. Interindividual differences in the within-person coupling between daily pain and affect were found with regard to general physical health conditions and general satisfaction with health. This study demonstrated the importance of focusing on within-person couplings between daily pain and affect beyond patient samples in order to better understand the maintenance of emotional stability despite daily hassles in older adults' everyday lives.

Repercusiones del Dolor Crónico en las Dinámicas de Pareja: Perspectivas de Mujeres con Fibromialgia

El objetivo de esta investigación fue comprender las repercusiones del dolor crónico en las dinámicas de pareja, desde la perspectiva de mujeres con fibromialgia. Se realizó un estudio cualitativo de diseño fenomenológico interpretativo en el cual se entrevistó a 15 mujeres. Las participantes reportaron inconformidad con el cambio de su rol en la relación. Además, ocultar el dolor fue una estrategia para evitar la sobreprotección y los conflictos. Las repercusiones en la percepción de la relación, los espacios compartidos, el apoyo de la pareja, la comunicación y la sexualidad se asociaron con la interferencia de los síntomas. Finalmente, la aparición de la enfermedad fue una oportunidad para fortalecer o fragmentar la relación.

Measuring pain-Physiological and self-rated measurements in relation to pain stimulation and anxiety

INTRODUCTION

The aim of the present study was to investigate how emotions influence pain, measured by one subjective self-rated measure, the numeric rating scale (NRS), and one objective physiological measure, the number of skin conductance responses (NSCR).

METHOD

Eighteen volunteers were exposed to conditions with pictorial emotional stimuli (neutral, positive, negative), authentic ICU-sound (noise, no-noise) and electrical stimulation (pain, no-pain) individually titrated to induce moderate pain. When using all combinations of picture inducing emotions, sound, and pain, each of these conditions (12 conditions lasting for 60 seconds each) were followed by pain ratings. Ratings of arousal (low to high) and valence (pleasant to unpleasant) were used as indicators of affective state for each condition. Mean NSCR was also measured throughout the experiment for each condition.

RESULTS

Even though NRS and NSCR increased during painful stimuli, they did not correlate during the trial. However, NSCR was positively correlated with the strength of the electrical stimulation, r = 0.48, P = 0.046, whereas NRS showed positive correlations with the anxiety level, assessed by affective ratings (arousal, r = 0.61, P < 0.001, and valence, r = 0.37, P < 0.001).

CONCLUSIONS

The NRS was strongly influenced by affective state, with higher pain ratings during more anxiety-like states, whereas NSCR correlated to the strength of electrical pain stimulation. That reported pain is moderated by anxiety, puts forward a discussion whether reduction of the anxiety level should be considered during analgesia treatment.

Pain Processing in Psychiatric Conditions: A Systematic Review

Pain is a universal, multidimensional experience with sensory, emotional, cognitive, and social components, which is fundamental to our environmental learning when functioning typically. Understanding pain processing in psychiatric conditions could provide unique insight into the underlying pathophysiology or psychiatric disease, especially given the psychobiological overlap with pain processing pathways. Studying pain in psychiatric conditions is likely to provide important insights, yet, there is a limited understanding beyond the work in depression and anxiety. This is a missed opportunity to describe psychiatric conditions in terms of neurobiological alterations. To examine the research into the pain experiences of these groups and the extent to which a-typicality is present, a systematic review was conducted. An electronic search strategy was developed and conducted in several databases. The current systematic review included 46 studies covering five Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5) disorders: autism, attention-deficit hyperactivity disorder (ADHD), schizophrenia, personality disorder, and eating disorders, confirming tentative evidence of altered pain and touch processing. Specifically, hyposensitivity is reported in schizophrenia, personality disorder and eating disorder, hypersensitivity in ADHD, and mixed results for autism. Review of the research highlights a degree of methodological inconsistency in the utilization of comprehensive protocols, the lack of which fails to allow us to understand whether a-typicality is systemic or modality specific.

Momentary assessment of everyday physical pain in outpatients with borderline personality disorder

Borderline personality disorder (BPD) is a severe psychiatric disorder associated with dysregulation in multiple domains of functioning. Physical health, and specifically pain, is one such domain that has gone understudied. Although evidence suggests that BPD is associated with chronic pain, few studies have examined nonchronic pain in the disorder. The current study used ambulatory assessment to examine momentary physical pain in everyday life in BPD outpatients (N = 26) and community comparisons (COM; N = 26) not in treatment for chronic pain (Nobservations = 5,458). We predicted and observed that BPD outpatients would report greater pain intensity and greater pain variability than COM comparisons. We also examined the relationship of pain and emotion dysregulation, a core feature of BPD, by testing the association between pain and negative affect concurrently and lagged over time. We predicted that momentary pain and negative affect would be associated in both groups, but that pain would predict negative affect more strongly in the BPD group. As predicted, concurrent pain and negative affect were associated in both groups, and groups differed significantly in terms of the association of lagged pain and next-assessment negative affect, with a negative association in the COM group. The current study represents a preliminary first step, finding that pain is relevant to the everyday experience of BPD individuals. This pain propensity may contribute to the elevated prevalence of BPD in chronic pain samples. Further, BPD individuals demonstrated emotional reactivity to pain, suggesting that pain may be a contributor to emotion dysregulation in this disorder. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Latent variable analysis of negative affect and its contributions to neural responses during shock anticipation

Negative affect is considered an important factor in the etiology of depression and anxiety, and is highly related to pain. However, negative affect is not a unitary construct. To identify specific targets for treatment development, we aimed to derive latent variables of negative affect and test their unique contributions to affective processing during anticipation of unpredictable, painful shock. Eighty-three subjects (43 with depression and anxiety spectrum disorders and 40 healthy controls) completed self-report measures of negative valence and underwent neuroimaging while exploring computer-simulated contexts with and without the threat of a painful, but tolerable, shock. Principal component analysis (PCA) extracted distinct components of general negative affect (GNA) and pain-related negative affect (PNA). While elevated GNA and PNA were both indicative of depression and anxiety disorders, greater PNA was more strongly related to task-specific anxious reactivity during shock anticipation. GNA was associated with increased precuneus and middle frontal gyrus activity, whereas PNA was related to increased bilateral anterior insula activity. Anterior insula activity mediated the relationship between PNA and task-specific anxious reactivity. In conclusion, GNA and PNA have distinct neural signatures and uniquely contribute to anxious anticipation. PNA, via insula activity, may relate to arousal in ways that could contribute to affective dysregulation, and thus may be an important treatment target.

Insights About the Neuroplasticity State on the Effect of Intramuscular Electrical Stimulation in Pain and Disability Associated With Chronic Myofascial Pain Syndrome (MPS): A Double-Blind, Randomized, Sham-Controlled Trial

Background: There is limited evidence concerning the effect of intramuscular electrical stimulation (EIMS) on the neural mechanisms of pain and disability associated with chronic Myofascial Pain Syndrome (MPS). Objectives: To provide new insights into the EIMS long-term effect on pain and disability related to chronic MPS (primary outcomes). To assess if the neuroplasticity state at baseline could predict the long-term impact of EIMS on disability due to MPS we examined the relationship between the serum brain-derived-neurotrophic-factor (BDNF) and by motor evoked potential (MEP). Also, we evaluated if the EIMS could improve the descending pain modulatory system (DPMS) and the cortical excitability measured by transcranial magnetic stimulation (TMS) parameters. Methods: We included 24 right-handed female with chronic MPS, 19-65 years old. They were randomically allocated to receive ten sessions of EIMS, 2 Hz at the cervical paraspinal region or a sham intervention (n = 12). Results: A mixed model analysis of variance revealed that EIMS decreased daily pain scores by -73.02% [95% confidence interval (CI) = -95.28 to -52.30] and disability due to pain -43.19 (95%CI, -57.23 to -29.39) at 3 months of follow up. The relative risk for using analgesics was 2.95 (95% CI, 1.36 to 6.30) in the sham group. In the EIMS and sham, the change on the Numerical Pain Scale (NPS0-10) throughout CPM-task was -2.04 (0.79) vs. -0.94 (1.18), respectively, (P = 0.01). EIMS reduced the MEP -28.79 (-53.44 to -4.15), while improved DPMS and intracortical inhibition. The MEP amplitude before treatment [(Beta = -0.61, (-0.58 to -0.26)] and a more significant change from pre- to post-treatment on serum BDNF) (Beta = 0.67; CI95% = 0.07 to 1.26) were predictors to EIMS effect on pain and disability due to pain. Conclusion: These findings suggest that a bottom-up effect induced by the EIMS reduced the analgesic use, improved pain, and disability due to chronic MPS. This effect might be mediated by an enhancing of corticospinal inhibition as seen by an increase in IC and a decrease in MEP amplitude. Likewise, the MEP amplitude before treatment and the changes induced by the EIMS in the serum BDNF predicted it's long-term clinical impact on pain and disability due MPS. The trial is recorded in ClinicalTrials.gov: NCT02381171.

Chronic pain: a consequence of dysregulated protective action

Introduction

Pain is considered to be one of a number of idiosyncratic, context-dependent 'protective actions' projected into the conscious domain by the central nervous system (CNS), as a result of a series of complex interactions in response to perceived threat. A model is described which proposes chronic pain and a variety of long-term, systemic functional neurological conditions to be a consequence of significant dysregulation of these protection systems.

The Model

Previous research has demonstrated that a cognitive-behavioural model, first described in 1995 by Surawy et al., for chronic fatigue has been successful in predicting the transition from acute to chronic states in a number of conditions. This model includes predisposing, precipitating and perpetuating biopsychosocial factors. This article discusses the potential role of these factors in affecting descending inhibition in the CNS, significantly altering its ability to modulate the threat detection system. The development of 'central sensitisation' is considered in this context.

Conclusion

This model proposes that chronic pain, chronic fatigue and other so-called functional neurological phenomena can, perhaps, be more helpfully seen as the actions of a dysregulated neurological protection system, rather than symptoms of an untreatable and deteriorating medical condition. Recommendations are made for the development of appropriate therapeutic interventions indicated by this model.

Temporal dynamics of pain: an application of regime-switching models to ecological momentary assessments in patients with rheumatic diseases

Advances in pain measurement using ecological momentary assessments offer novel opportunities for understanding the temporal dynamics of pain. This study examined whether regime-switching models, which capture processes characterized by recurrent shifts between different states, provide clinically relevant information for characterizing individuals based on their temporal pain patterns. Patients with rheumatic diseases (N = 116) provided 7 to 8 momentary pain ratings per day for 2 weekly periods, separated by 3 months. Regime-switching models extracted measures of Average pain (mean level over time), Amplitude (magnitude of shifts in pain levels), Persistence (average duration of pain states), and Dominance (relative duration of higher vs lower pain states) for each patient and assessment period. After controlling for Average pain, the Persistence of pain states uniquely predicted emotional functioning measures, whereas the Dominance of higher pain uniquely predicted physical functioning and pain interference. Longitudinal analyses of changes over the 3 months largely replicated cross-sectional results. Furthermore, patients' retrospective judgments of their pain were uniquely predicted by Amplitude and Dominance of higher pain states, and global impressions of change over the 3 months were predicted by changes on Dominance, controlling for Average pain levels. The results suggest that regime-switching models can usefully capture temporal dynamics of pain and can contribute to an improved measurement of patients' pain intensity.

Loneliness as a mediator of the relationship between shame and health problems in young people exposed to childhood violence

RATIONALE

Shame related to childhood violence can be detrimental to mental and physical health. Shame may erode social bonds.

OBJECTIVE

In this study we tested whether loneliness is an important pathway between violence-related shame and health problems.

METHOD

Individuals who reported exposure to childhood violence in a telephone interview survey in 2013 (wave one) were re-contacted 12-18 months later (wave two), as part of a more general survey of the Norwegian adult population. In total, 505 adolescent and young adult participants (mean age = 21 years) responded to questions about violence exposure, violence-related shame, loneliness, anxiety/depression symptoms, and somatic health complaints. We used counterfactually based causal mediation analysis within the structural equation modelling framework to test whether loneliness mediated a potential association between shame and health.

RESULTS

Shame had a profound effect on anxiety/depression symptoms and we identified both direct and indirect effects. Loneliness mediated about one third of the relationship between shame and anxiety/depression symptoms. The relationship between shame and somatic health complaints was weaker in total, but this more modest effect largely occurred indirectly through loneliness.

CONCLUSIONS

Our results add to the literature by highlighting the role of loneliness in the relationship between shame and health. Shame may have the potential to break down social connectedness, with a detrimental effect on health. Clinicians may find it helpful to pay close attention to the way shame regulates social interaction. Preventing social isolation and loneliness may promote good health in violence victims.

Psychological health is associated with knee pain and physical function in patients with knee osteoarthritis: an exploratory cross-sectional study

Background

Depressive symptoms are a major comorbidity in older adults with knee osteoarthritis (OA). However, the type of activity-induced knee pain associated with depression has not been examined. Furthermore, there is conflicting evidence regarding the association between depression and performance-based physical function. This study aimed to examine (i) the association between depressive symptoms and knee pain intensity, particularly task-specific knee pain during daily living, and (ii) the association between depressive symptoms and performance-based physical function, while considering other potential risk factors, including bilateral knee pain and ambulatory physical activity.

Methods

Patients in orthopaedic clinics (n = 95; age, 61–91 years; 67.4% female) who were diagnosed with radiographic knee OA (Kellgren/Lawrence [K/L] grade ≥ 1) underwent evaluation of psychological health using the Geriatric Depression Scale (GDS). Knee pain and physical function were assessed using the Japanese Knee Osteoarthritis Measure (JKOM), 10-m walk, timed up and go (TUG), and five-repetition chair stand tests.

Results

Ordinal logistic regression analysis showed that depression, defined as a GDS score ≥ 5 points, was significantly associated with a worse score on the JKOM pain-subcategory and a higher level of task-specific knee pain intensity during daily living, after being adjusted for age, sex, body mass index (BMI), K/L grade, and ambulatory physical activity. Furthermore, depression was significantly associated with a slower gait velocity and a longer TUG time, after adjusting for age, sex, BMI, K/L grade, presence of bilateral knee pain, and ambulatory physical activity.

Conclusions

These findings indicate that depression may be associated with increased knee pain intensity during daily living in a non-task-specific manner and is associated with functional limitation in patients with knee OA, even after controlling for covariates, including bilateral knee pain and ambulatory physical activity.

Electronic supplementary material

The online version of this article (10.1186/s40359-018-0234-3) contains supplementary material, which is available to authorized users.

Effects of Cognitive-Behavioral Therapy on Empathy in Patients with Chronic Pain

OBJECTIVE

Cognitive-behavioral therapy (CBT) is effective in patients with chronic pain. However, the efficacy of CBT for impaired empathy has not been studied in this population. We investigated the effect of CBT on empathy in patients with chronic pain.

METHODS

Patients with severe chronic pain were recruited. Empathy was assessed before and after CBT using the Interpersonal Reactivity Index (IRI). The patients underwent eight sessions over the course of 1 month conducted. Additional symptoms were assessed using the Short-Form McGill Pain Questionnaire (SF-MPQ), Beck Depression Inventory, Beck Anxiety Inventory, World Health Organization Quality of Life Scale Abbreviated Version, and the Scale for Suicide Ideation.

RESULTS

A total of 26 participants were included. Pre-CBT pain severity assessed using the SF-MPQ was significantly correlated with the IRI-empathic concern subscale score (p=0.021), and the relationship remained significant after adjusting for sex, age, education level, and marital status. After CBT, the IRI-perspective-taking subscale scores (p=0.004) increased significantly and the IRI-personal distress subscale scores (p=0.013) decreased significantly in all participants. The SF-MPQ scores increased significantly (p=0.021).

CONCLUSION

CBT improved empathy in patients with chronic pain independent of its effect on pain, suggesting that CBT is useful for improving interpersonal relationships in patients with chronic pain.

Interpersonal behavior in anticipation of pain: a naturalistic study of behavioral mimicry prior to surgery

Current and anticipated pain relate to mimicry behavior in divergent ways, which may bear upon the elicitation of social support during the experience of pain.

Introduction:

Social relationships facilitate coping with pain, but research suggests that it may be difficult to galvanize social support during an episode of acute pain.

Objectives:

The current research examined whether social connections are optimized in the anticipation of pain by observing patients' mimicry of an interaction partner prior to surgery. We hypothesized that when controlling for their current experience of pain, patients' anticipation of pain would be associated with greater mimicry of an interaction partner.

Methods:

Sixty-five patients were interviewed in the waiting room of a maxillofacial surgery unit prior to the removal of an impacted wisdom tooth. Patients' spontaneous mimicry of an interviewer was observed. Patients then rated the quality and intensity of their anticipated pain, as well as the intensity of their current pain and their affective distress.

Results:

Anticipated pain, current pain, and affective distress were positively correlated. Current pain was associated with less frequent mimicry of an interaction partner. The zero-order correlation between anticipated pain and mimicry did not reach conventional levels of significance; however, when controlling for current pain, anticipated pain predicted more frequent mimicry of an interaction partner. The relationship between anticipated pain and mimicry was not explained by affective distress.

Conclusion:

This is the first study to demonstrate that anticipated and current pain relate to behavioral mimicry in divergent ways. Further research is needed to investigate whether the current pattern of results generalizes to other interpersonal behaviors that facilitate social bonds.

Understanding cultural influences on back pain and back pain research

Low back pain is highly prevalent and places a considerable burden on individuals, their families and communities. This back pain burden is unequally distributed around the world and within populations. Clinicians and researchers addressing back pain should be aware of the cultural, social and political context of back pain patients and how this context can influence pain perception, disability and health care use. Culture, which influences the beliefs and behaviour of individuals within a social group, could be considered an important contributor to the unequal distribution of back pain. However, there is paucity of high-quality research exploring the influence of culture on the experience and management of back pain. Further development and testing of specific tools, assessment methods and communication strategies are needed to improve our understanding of how cultural practices, values and identifications affect those dealing with back pain.

Context sensitive regulation of pain and emotion: Development and initial validation of a scale for context insensitive avoidance

BACKGROUND AND AIMS

Context insensitivity has been put forward as a potential mechanism explaining the high co-occurrence of pain and emotional distress. In the pain literature, the concept has only been introduced at a theoretical level and an assessment tool for exploring its impact is lacking. In an interpersonal setting, a core aspect of context sensitivity and insensitivity concerns when to disclose and when to avoid expressing pain and related distress. Both context insensitive disclosure and context insensitive avoidance may hamper interpersonal support and fuel the problem. This exploratory study describes an attempt to develop a self-report instrument to assess tendencies to disclose vs. avoid expressions of pain and related distress, as well as self-perceived adjustment of disclosure vs. avoidance to the context.

METHODS

A pool of items was systematically developed to assess different aspects of context insensitivity, including disclosure vs. avoidance of expression. 105 participants with persistent pain were recruited at pain rehabilitation clinics (80% of the sample) and in a university setting (20% of the sample). The participants responded to the pool of items as well as to a number of validated self-report instruments covering pain, pain-related disability, pain catastrophizing, emotion regulation tendencies, self-compassion and pain acceptance. The analyses explored the factorial structure of the initial instrument, as well as the criterion and construct validity.

RESULTS

The analyses confirmed a stable underlying structure of the initial scale, with four distinct factors explaining 64.4% of the total variance. However, the criterion and construct validity could only be confirmed for one of the factors, which contained items reflecting context insensitive avoidance of expression. Consequently, only this factor, demonstrating very good internal consistency, was kept in the final version of the instrument which was named context insensitive avoidance (CIA).

CONCLUSIONS

We found support for the final version of our instrument, capturing one prominent aspect of context insensitivity. Avoidance of expression was related to higher ratings of pain, disability, catastrophizing and suppression as well as to lower levels of self-compassion. We encourage further studies to explore the impact of context insensitive avoidance for regulating pain and associated negative emotions. Yet, more research is needed that goes beyond self-report and includes other aspects of context. It is urgent to develop systematic ways for assessing context insensitivity, as it will enhance our understanding of regulatory strategies as potential transdiagnostic mechanisms in pain and emotion.

IMPLICATIONS

This tool for assessing contextually insensitive avoidance of expression could potentially be used both clinically and in future research to advance our understanding of comorbid problems with pain and emotional distress. Further research is needed to develop methods for assessing other aspects of context insensitivity to fully understand its impact in patients suffering from pain.

Gray matter alteration associated with pain catastrophizing in patients 6 months after lumbar disk surgery: a voxel-based morphometry study

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The link between pain catastrophizing and the differential effect of the components magnification and helplessness on brain morphology in patients with low back pain

Introduction:

Pain catastrophizing (PC), the increased attention to harmful aspects of pain (magnification), and the belief of low controllability (helplessness) has been shown to be important in the maintenance of pain. A growing research on structural alterations in chronic pain revealed an association between PC and brain areas that are involved in affective and cognitive pain processing. However, little is known about a differential effect of the components magnification and helplessness.

Objective:

The aim of this study was to identify brain regions associated with overall PC and with the single components of magnification and helplessness.

Methods:

We investigated 29 patients 6 months after lumbar disk surgery using voxel-based morphometry. Magnification and helplessness were assessed with subscales of the Avoidance-Endurance Questionnaire (AEQ); overall PC was computed using the sum score. The structural brain imaging data were preprocessed and analyzed using SPM8 and VBM8. Multiple regression analyses were performed with PC scales as predictors and depression as covariate.

Results:

Pain catastrophizing was significantly associated with cortical gray matter in brain areas involved in processing attentional, sensory, and affective aspects of pain, including the left posterior cingulate cortex, supplementary motor area, and medial frontal gyrus. In addition, we provide preliminary evidence for brain structure association related to magnification and helplessness.

Conclusion:

This study provides evidence for PC-related structural alterations in patients with low back pain, which are consistent with findings from previous research in different chronic pain disorders. This study is the first to evaluate brain changes related to differential domains of PC.

Relationships between components of emotional intelligence and physical pain in alcohol-dependent patients

PURPOSE

Chronic pain is a significant comorbidity in individuals with alcohol dependence (AD). Emotional processing deficits are a substantial component of both AD and chronic pain. The aim of this study was to analyze the interrelations between components of emotional intelligence and self-reported pain severity in AD patients.

PATIENTS AND METHODS

A sample of 103 participants was recruited from an alcohol treatment center in Warsaw, Poland. Information concerning pain level in the last 4 weeks, demographics, severity of current anxiety and depressive symptoms, as well as neuroticism was obtained. The study sample was divided into "mild or no pain" and "moderate or greater pain" groups.

RESULTS

In the logistic regression model, across a set of sociodemographic, psychological, and clinical factors, higher emotion regulation and higher education predicted lower severity, whereas increased levels of anxiety predicted higher severity of self-reported pain during the previous 4 weeks. When the mediation models looking at the association between current severity of anxiety and depressive symptoms and pain severity with the mediating role of emotion regulation were tested, emotion regulation appeared to fully mediate the relationship between depression severity and pain, and partially the relationship between anxiety severity and pain.

CONCLUSION

The current findings extend previous results indicating that emotion regulation deficits are related to self-reported pain in AD subjects. Comprehensive strategies focusing on the improvement of mood regulation skills might be effective in the treatment of AD patients with comorbid pain symptoms.

5-HT in the dorsal raphe nucleus is involved in the effects of 100-Hz electro-acupuncture on the pain-depression dyad in rats

The pain-depression dyad is becoming widespread in the clinic and is attracting increasing attention. A previous study by our group found that 100-Hz electro-acupuncture (EA), but not 2-, 50- and 2/100-Hz EA, was effective against the reserpine-induced pain-depression dyad. This finding is in contrast to the fact that low-frequency EA is commonly used to treat supraspinal-originating diseases. The present study aimed to investigate the mechanism underlying the effects of 100-Hz EA on the pain-depression dyad. Repeated reserpine injection was found to induce allodynia and depressive behaviors in rats. It decreased 5-hydroxytryptamine (5-HT) levels and immunoreactive expressions in the dorsal raphe nucleus (DRN). 100-Hz EA alleviated the pain-depression dyad and upregulated 5-HT in the DRN of reserpine-injected rats. Intracerebroventricular injection of para-chlorophenylalanine, an inhibitor of 5-HT resynthesis, suppressed the upregulation of 5-HT in the DRN by 100-Hz EA and partially counteracted the analgesic and anti-depressive effects of 100-Hz EA. The present study was the first to demonstrate that 5-HT in the DRN is involved in mediating the analgesic and anti-depressive effects of 100-Hz EA on the pain-depression dyad. This finding provided a scientific basis for high-frequency EA as a potential treatment for the pain-depression dyad.

Emotion regulation strategies mediate the associations of positive and negative affect to upper extremity physical function

BACKGROUND

The Gross process model of emotion regulation holds that emotion-eliciting situations (e.g. musculoskeletal illness) can be strategically regulated to determine the final emotional and behavioral response. Also, there is some evidence that innate emotional traits may predispose an individual to a particular regulating coping style.

METHODS

We enrolled 107 patients with upper extremity musculoskeletal illness in this cross-sectional study. They completed self-report measures of positive and negative affect, emotion regulation strategies (cognitive reappraisal and expressive suppression), upper extremity physical function, pain intensity, and demographics. We used Preacher and Hayes' bootstrapping approach to process analysis to infer the direct effect of positive and negative affect on physical function as well as their indirect effects through activation of emotion regulation strategies.

RESULTS

Negative affect was associated with decreased physical function. The association was partly mediated by expressive suppression (b (SE)=-.10 (.05), 95% BCa CI [-.21, -.02]). Positive affect was associated with increased physical function. Cognitive reappraisal partially mediated this association (b (SE)=.11 (.05), 95% BCa CI [.03, .24]). After controlling for pain intensity, the ratio of the mediated effect to total effect grew even larger in controlled model comparing to uncontrolled model (33% vs. 26% for expressive suppression and 32% vs. 30% for cognitive reappraisal).

CONCLUSIONS

The relationships between affect, emotion regulation strategies and physical function appear to be more dependent on the emotional response to an orthopedic condition rather than the intensity of the nociceptive stimulation of the pain. Findings support integration of emotion regulation training in skill-based psychotherapy in this population to mitigate the effect of negative affect and enhance the influence of positive affect on physical function.