Pain perception and processing in individuals with posttraumatic stress disorder: a systematic review with meta-analysis

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.

Sensory alterations in post-traumatic stress disorder

PTSD is characterized by difficulties in accurately evaluating the threat value of sensory stimuli. While the role of canonical fear and threat neural circuitry in this ability has been well studied, recent lines of evidence suggest a need to include more emphasis on sensory processing in the conceptualization of PTSD symptomology. Specifically, studies have demonstrated a strong association between variability in sensory processing regions and the severity of PTSD symptoms. In this review, we summarize recent findings that underscore the importance of sensory processing in PTSD, in addition to the structural and functional characteristics of associated sensory brain regions. First, we discuss the link between PTSD and various behavioral aspects of sensory processing. This is followed by a discussion of recent findings that link PTSD to variability in the structure of both gray and white matter in sensory brain regions. We then delve into how brain activity (measured with task-based and resting-state functional imaging) in sensory regions informs our understanding of PTSD symptomology.

Mediators of the association between childhood trauma and pain sensitivity in adulthood: a Multidisciplinary Approach to the Study of Chronic Pelvic Pain Research Network analysis

ABSTRACT

Urologic chronic pelvic pain syndrome (UCPPS) is a complex, debilitating condition in which patients often report nonpelvic pain in addition to localized pelvic pain. Understanding differential predictors of pelvic pain only vs widespread pain may provide novel pathways for intervention. This study leveraged baseline data from the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network's Symptom Pattern Study to investigate the impact of childhood sexual and nonsexual violent trauma on pelvic and nonpelvic pain sensitivity among adult patients with UCPPS, as well as potential mediators of this association. Study participants who met inclusion criteria for UCPPS completed questionnaires assessing childhood and recent trauma, affective distress, cognitive dysfunction, and generalized sensory sensitivity. Experimental pain sensitivity was also evaluated using standardized pressure pain applied to the pubic region and the arm. Bivariate analyses showed that childhood violent trauma was associated with more nonviolent childhood trauma, more recent trauma, poorer adult functioning, and greater pain sensitivity at the pubic region, but not pain sensitivity at the arm. Path analysis suggested that childhood violent trauma was indirectly associated with pain sensitivity at both sites and that this indirect association was primarily mediated by generalized sensory sensitivity. More experiences of recent trauma also contributed to these indirect effects. The findings suggest that, among participants with UCPPS, childhood violent trauma may be associated with heightened pain sensitivity to the extent that trauma history is associated with a subsequent increase in generalized sensory sensitivity.

Factors Associated With Distress Related to Posttraumatic Stress Disorder at the End of Life Among U.S. Veterans

CONTEXT

Posttraumatic stress disorder (PTSD) may emerge or re-emerge at end of life (EOL), increasing patient suffering. Understanding factors associated with PTSD at EOL may assist clinicians in identifying high risk veterans.

OBJECTIVES

To determine rates of and variables associated with PTSD-related distress at EOL.

METHODS

Retrospective observational cohort study including veterans who died within a Veterans Affairs (VA) inpatient setting between October 1, 2009 and September 30, 2018 whose next-of-kin completed the Bereaved Family Survey (BFS; N = 42,474). Our primary outcome was PTSD-related distress at EOL, as reported by veteran decedents' next-of-kin on the BFS. Predictors of interest included combat exposure, demographic variables, medical and psychiatric comorbidity, primary serious illness, and palliative care support.

RESULTS

Veteran decedents were majority male (97.7%), non-Hispanic white (77.2%), 65 years or older (80.5%), without combat exposure (80.1%). Almost one in ten (8.9%) veteran decedents experienced PTSD-related distress at EOL. In adjusted analyses, combat exposure, younger age, male sex, and non-white race were associated with PTSD-related distress at EOL. High overall medical comorbidity, dementia, and psychiatric comorbidities including both substance use disorder and depression, were also associated with PTSD-related distress at EOL. Palliative care consultation and emotional support were associated with decreased odds of PTSD-related distress, while pain was associated with increased odds of PTSD-related distress at EOL.

CONCLUSION

Trauma and PTSD screening, pain management, and providing palliative care and emotional support at EOL, particularly in at-risk groups such as veterans from racial/ethnic minority backgrounds and those with dementia, are critical to decreasing PTSD-related distress at EOL.

Relations between PTSD symptom clusters and pain in three trauma-exposed samples with pain

OBJECTIVES

Little is known about how the individual PTSD symptom clusters relate to intensity and interference of pain and whether these relationships differ across clinical groups. The present study examines relations between PTSD symptom clusters and pain in three trauma-exposed, unique clinical groups: 1) adults seeking treatment for chronic pain with current symptoms of PTSD, 2) trauma affected refugees seeking treatment for PTSD and chronic pain; and 3) individuals identified at admission to the emergency ward after whiplash injury.

METHODS

Network analysis was used to assess unique relations between pain intensity, pain interference, re-experiencing, avoidance, numbing, hyperarousal, depression, and anxiety separately in each sample. Links between PTSD clusters and pain were then compared within and between samples.

RESULTS

No within-group differences were identified for the links between pain and any of PTSD clusters in the chronic pain and refugee groups. In the whiplash group, hyperarousal was more strongly related to pain than re-experiencing, avoidance, and numbing. Between group comparisons revealed a more pronounced relationship between hyperarousal and pain in the whiplash group, with no between-group differences between the chronic pain and refugee groups.

CONCLUSIONS

The findings suggest that when depression and anxiety are accounted for, few unique associations are found between pain and the PTSD symptom clusters in trauma-exposed samples with pain, with the exception of a link between pain and hyperarousal in individuals with whiplash-related PTSD symptoms.

Performance and acceptability of the Stressful Life Events Screening Questionnaire in a chronic pain population: a mixed-methods study

Introduction

Pain-related fear, anxiety, and avoidance may play key roles in the chronification of pain and related disability. For practitioners, knowledge about the source or drivers of these fears, including patients' exposure to potentially traumatic events (PTEs) and related posttraumatic stress symptoms, could be particularly helpful in guiding their treatment approach.

Objectives

We aimed to investigate whether the use of a brief screening for PTEs could help inform chronic pain treatment.

Methods

The performance and acceptability of the Stressful Life Events Screening Questionnaire (SLESQ) was assessed among 567 adult patients (59% women, mean age 48.1 years) meeting at a hospital outpatient pain clinic. The sensitivity, specificity, and 20 months temporal stability of the SLESQ, assessing exposure to 14 specific trauma types followed by a 15th item capturing exposure to "other events," were assessed through digital administration and follow-up interviews with 55 participants. The qualitative responses of 158 participants reporting exposure to "other events" were reviewed and assessed based on fulfillment of the A Criterion for traumatic events in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. The acceptability of the SLESQ was assessed in clinical interviews with 12 participants.

Results

The SLESQ demonstrated acceptable sensitivity (70.0%), high specificity (94.9%), and moderate temporal stability (κ = 0.66, P < 0.001). Participants' qualitative elaborations of "other events" were largely (76.3%) consistent with Criterion A events. The screening was well accepted and welcomed.

Conclusion

The results indicate that the use of a brief screening for potential trauma may be helpful to guide clinical practice in chronic pain settings.

The role of post-trauma stress symptoms in the development of chronic musculoskeletal pain and disability: A systematic review

BACKGROUND AND OBJECTIVE

Traumatic injuries are amongst the leading causes of death and disability in the world across all age groups. This systematic review aimed to (1) describe the role of post-traumatic stress symptoms (PTSS) on the development of chronic pain and/or pain-related disability following musculoskeletal trauma and (2) report pain and or pain-related disability by injury severity/type.

DATABASE AND DATA TREATMENT

Electronic databases were searched, from inception to 31 November 2021 and updated on 10 May 2022, to identify studies in which: participants were adults aged ≥16 years sustaining any traumatic event that resulted in one or more musculoskeletal injuries; an outcome measure of PTSS was used within 3 months of a traumatic event; the presence of pain and/or pain-related disability was recorded at a follow-up of 3 months or more. Two reviewers independently screened papers and assessed the quality of included studies.

RESULTS

Eight studies were included. Owing to between-study heterogeneity, the results were synthesized using a narrative approach. Five studies investigated the relationship between PTSS and pain. Participants with PTSS were more likely to develop persistent pain for at least 12 months post-injury. Six studies assessed the relationship between PTSS and pain-related disability. The results suggest that patients with PTSS had significantly higher disability levels for at least 12 months post-injury.

CONCLUSION

Findings from this comprehensive systematic review support a clear relationship between PTSS post-injury and future pain/disability, with the potential importance of certain PTSS clusters (hyper-arousal and numbing).

SIGNIFICANCE

The findings of this systematic review indicate an association between PTSS reported within 3 months of a traumatic musculoskeletal injury and the development of longer-term pain and disability. The PTSS clusters of 'hyper-arousal' and 'numbing' appear to be of particular importance in this relationship.

PROSPERO REGISTRATION NUMBER

CRD42021285243.

Traumatic Life Experience and Pain Sensitization: Meta-analysis of Laboratory Findings

OBJECTIVES

Psychological trauma often co-occurs with pain. This relationship has been explored using laboratory pain measures; however, findings have been mixed. Previous studies have limited operationalization of trauma (eg, posttraumatic stress disorder) or pain (eg, pain thresholds), which may contribute to conflicting results. Further, prior reviews likely underrepresent trauma experiences among people who are not receiving clinical care, limiting generalizability.

MATERIALS AND METHODS

We systematically reviewed the existing literature on the relationship between psychological trauma (eg, car accidents, sexual assault, childhood abuse, neglect) and laboratory pain (ie, quantitative sensory testing measures of pain threshold, intensity, summation, modulation), using inclusive criteria. The direction of the relationship between psychological trauma and pain sensitivity was evaluated, and moderation by purported pain mechanism (ie, pain detection, suprathreshold pain, central sensitization, inhibition) was explored.

RESULTS

Analyses were conducted using 48 studies that provided 147 effect sizes. A multivariate random-effects model with robust variance estimation resulted in a small but statistically significant overall effect size of g=0.24 (P=0.0002), reflecting a positive association between psychological trauma and enhanced laboratory pain sensitivity. Upon examination of mechanistic moderators, this relationship appears driven by effects on pain detection (g=0.28, P=0.002) and central sensitization (g=0.22, P=0.04). While effect sizes were similar across all moderators, effects on suprathreshold pain and inhibition were not statistically significant.

DISCUSSION

Findings demonstrate an overall pattern of trauma-related pain enhancement and point to central sensitization as a key underlying mechanism.

Distress intolerance and pain catastrophizing as mediating variables in PTSD and chronic noncancer pain comorbidity

OBJECTIVES

Several studies have demonstrated posttraumatic stress disorder (PTSD) and chronic pain comorbidity. However, there is a lack of research on the psychological variables that might explain their co-occurrence. We investigated the mediating role of distress intolerance and pain catastrophizing in this relationship.

METHODS

A moderated mediation model was tested. The sample comprised 114 individuals with chronic noncancer pain (90 women and 24 men; mean age, of 60.04 years [SD=9.76]).

RESULTS

Catastrophizing had a significant effect on PTSD. Distress intolerance mediated catastrophizing and PTSD, and pain intensity moderated this relationship.

CONCLUSIONS

New insights are provided into the psychological variables that may explain PTSD and chronic noncancer pain comorbidity.

Posttraumatic Stress Symptoms and Pain Sensitization After Whiplash Injury: A Longitudinal Cohort Study With Quantitative Sensory Testing

Posttraumatic stress symptoms (PTSS) are common after whiplash injury and are associated with poor recovery. The acute stress response may lead to pain sensitization and widespread pain, thereby compromising recovery. To our knowledge, no longitudinal study has assessed the associations between early PTSS and pain sensitization over time using quantitative sensory testing (QST). The aim of this study was to compare participants with different levels of PTSS, as measured by the impact of event scale (IES; subclinical 0–8, mild 9–25, and clinical ≥ 26) at baseline (<10-day post-injury) and at a follow-up of 1, 3, 6, and 12-month post-injury on pain sensitivity, neck mobility, pain distribution, and pain intensity. In total, 740 participants were recruited from emergency units or general practitioners with acute neck pain after a whiplash injury. The clinical PTSS group showed increased pain sensitivity on all QSTs at all time points compared to the subclinical PTSS group. Also, the clinical PTSS group showed significantly lower neck mobility at all time points except for a 3-month follow-up compared to the subclinical PTSS group. Moreover, the clinical PTSS group showed more widespread pain and self-reported headache and neck pain intensity at all time points compared to the subclinical PTSS group. This study emphasizes that participants with clinical levels of PTSS constitute a high-risk group that is sensitized to pain early after the injury. Hence, screening for PTSS within the 1st week after whiplash injury for those who experience high levels of pain intensity and distress may be an important clinical procedure in the assessment and treatment of whiplash-associated disorders (WAD).

A Cross-Sectional Time Course of COVID-19 Related Worry, Perceived Stress, and General Anxiety in the Context of Post-Traumatic Stress Disorder-like Symptomatology

The COVID-19 pandemic within the United States of America resulted in over 800,000 deaths as of February 2022 and has been addressed by social distancing or stay-at-home measures. Collective prolonged multimodal trauma on this scale is likely to elicit symptomatology in the general population consistent with post-traumatic stress disorder (PTSD), somatization, anxiety, and stress. The psychological component of this response contributes substantially to the burden of this disease worldwide. This cross-sectional study examines the relationship between COVID-19-related concern, anxiety, and perceived stress on PTSD-like symptomatology over the course of the COVID-19 pandemic. Participants were recruited via social media within the United States of America between 8th May 2020 and 11th August 2021 to complete an internet questionnaire including mood, personality, and COVID-19-specific scales. General anxiety and PTSD-like symptomatology were above the screening cutoffs for most respondents. These measures increased in severity over the pandemic, with the change point of our Concern scale preceding that of the other significant measures. Measures of COVID-19-related concern, generalized anxiety, and PTSD-like symptomatology were strongly correlated with each other. Anxiety, perceived stress, and PTSD-like symptomatology are strongly interrelated, increase with pandemic length, and are linked to reported levels of concern over COVID-19. These observations may aid future research and policy as the pandemic continues.

Understanding Pain and Trauma Symptoms in Veterans From Resting-State Connectivity: Unsupervised Modeling

Trauma and posttraumatic stress are highly comorbid with chronic pain and are often antecedents to developing chronic pain conditions. Pain and trauma are associated with greater utilization of medical services, greater use of psychiatric medication, and increased total cost of treatment. Despite the high overlap in the clinic, the neural mechanisms of pain and trauma are often studied separately. In this study, resting-state functional magnetic resonance imaging (rs-fMRI) scans were completed among a diagnostically heterogeneous sample of veterans with a range of back pain and trauma symptoms. Using Group Iterative Multiple Model Estimation (GIMME), an effective functional connectivity analysis, we explored an unsupervised model deriving subgroups based on path similarity in a priori defined regions of interest (ROIs) from brain regions implicated in the experience of pain and trauma. Three subgroups were identified by patterns in functional connection and differed significantly on several psychological measures despite similar demographic and diagnostic characteristics. The first subgroup was highly connected overall, was characterized by functional connectivity from the nucleus accumbens (NAc), the anterior cingulate cortex (ACC), and the posterior cingulate cortex (PCC) to the insula and scored low on pain and trauma symptoms. The second subgroup did not significantly differ from the first subgroup on pain and trauma measures but was characterized by functional connectivity from the ACC and NAc to the thalamus and from ACC to PCC. The third subgroup was characterized by functional connectivity from the thalamus and PCC to NAc and scored high on pain and trauma symptoms. Our results suggest that, despite demographic and diagnostic similarities, there may be neurobiologically dissociable biotypes with different mechanisms for managing pain and trauma. These findings may have implications for the determination of appropriate biotype-specific interventions that target these neurological systems.

Trauma and pain sensitization in youth with chronic pain

Greater posttraumatic stress symptoms were associated with higher experimental pain tolerance. Pain may trigger dissociation in youth with chronic pain and higher posttraumatic stress symptoms.

Introduction:

Chronic pain (pain lasting ≥3 months) co-occurs with internalizing mental health issues, such as posttraumatic stress symptoms (PTSS), at high rates in youth. The mechanisms underlying these relationships remain unclear. Posttraumatic stress symptoms, including re-experiencing (eg, intrusive memories), alterations in cognition and mood, hyperarousal, and avoidance could lead to altered neuronal processing, pain sensitization, and greater reports of pain. However, the relationships between PTSS and pain sensitization in youth with chronic pain are not known.

Methods:

Youth (n = 165) aged 10 to 18 years were recruited from outpatient multidisciplinary chronic pain programs. Symptoms of PTSS were assessed using psychometrically sound questionnaires. Youth also underwent a cold-pressor task, the most commonly used experimental pain induction technique. During this task, they reported on their expected pain, actual pain intensity, and pre- and post-state pain catastrophizing. Their pain threshold was recorded. A multivariate general linear model was used to examine the relationships between PTSS, ratings of pain intensity, state pain catastrophizing, and pain threshold, controlling for age, gender, ethnicity, anxiety, and depressive symptoms.

Results:

Higher PTSS were associated with greater pain thresholds (P = 0.03) and higher pre- and post-state pain catastrophizing (P ≤ 0.05).

Conclusions:

Individuals with higher PTSS may avoid or dissociate from pain-inducing stimuli, thus leading to higher pain thresholds. However, individuals with higher PTSS also tend to catastrophize prior to and following exposure to pain. Avoidant and pain catastrophizing behaviors may serve to perpetuate chronic pain conditions. Future research is needed to determine how PTSS are related to pain sensitization prior to the development of chronic pain in at-risk youth.

Impact of an opioid prescribing alert system on patients with posttraumatic stress disorder

BACKGROUND AND OBJECTIVES

Posttraumatic stress disorder (PTSD) is associated with higher rates of chronic pain and increased risk of developing Opioid use disorder. This paper evaluates the impact of PRIMUM, an electronic health record-embedded (EHR) clinical decision support intervention on opioid prescribing patterns for patients with diagnosis of PTSD.

METHODS

Inpatient, emergency department (ED), urgent care, and outpatient encounters with ICD-10 codes F43.1 (PTSD), F43.10 (PTSD, unspecified), F43.11 (PTSD, acute), and F43.12 (PTSD, chronic) at Atrium Health between 1/1/2016 and 12/29/2018 were included in the study.

RESULTS

A total of 3121 patients with a diagnosis of PTSD were seen in 37,443 encounters during the study period. Ten percent (n = 3761) of the encounters resulted in prescriptions for opioids and PRIMUM alerts were triggered in 1488 of these encounters. These alerts resulted in "decision influenced" for 17% of patients (n = 255) or no prescriptions for opioids or benzodiazepines for 5.8% (n = 86). The majority of the prescriptions were below 50 Morphine milligram equivalents (MME)/day, but there were 570 (15.5%) prescriptions for doses of 50-90 MME and 721 (19.6%) prescriptions for >90 MME/day.

DISCUSSION AND CONCLUSION

The PRIMUM alert system helps improve patient safety. PRIMUM affected clinician decisions 17% of the time, and the effect was greater in patients with opioid overdose history and those presenting for early refills.

SCIENTIFIC SIGNIFICANCE

The effectiveness of clinical support interventions for opioid prescribing for patients with PTSD has not been documented previously. Our findings provide novel evidence that the EHR can be used to improve patient safety among patients with PTSD in the context of substance use.