Attentional Avoidance is Associated With Increased Pain Sensitivity in Patients With Chronic Posttraumatic Pain and Comorbid Posttraumatic Stress

High level of post-traumatic stress symptoms in patients with chronic neck pain is associated with poor mental health but does not moderate the outcome of a multimodal physiotherapy programme

INTRODUCTION

Chronic traumatic neck pain has a high prevalence of post-traumatic stress symptoms (PTSS). However, whether PTSS moderates treatment effects is unknown. This study investigated: 1) whether PTSS was associated with patient-reported outcomes and clinical test results at baseline; 2) whether PTSS moderated the effect of a multimodal physiotherapy intervention of exercise therapy and patient education; and 3) whether adherence to the intervention differed across PTSS groups.

METHODS

Secondary data analysis from a randomized controlled trial on chronic neck pain with 12-month follow-up was conducted. Patients were divided into three groups (NT = non-traumatic, LT = traumatic low PTSS, HT = traumatic high PTSS) based on self-reported onset of pain and the Impact of Event Scale. The baseline data were used to analyze the association of PTSS with patient demographics and scores of physical and mental health-related quality of life, depression, neck-related disability, kinesiophobia, and clinical tests. Baseline, 4-month and 12-month follow-up data were analyzed to investigate possible moderating effects on outcomes. Data on adherence were collected at four months.

RESULTS

115 participants were included (NT n = 45; LT n = 46; HT n = 24). The HT group reported lower mental health scores and more depressive symptoms at baseline. PTSS did not significantly moderate the treatment effect on any outcomes. The HT group tended to have lower adherence to the multimodal physiotherapy intervention than the LT group.

CONCLUSION

For patients with traumatic neck pain, high levels of PTSS are associated with poorer psychological outcomes but do not affect the outcomes of multimodal physiotherapy intervention.

The Roles of Endogenous Opioids in Placebo and Nocebo Effects: From Pain to Performance to Prozac

Placebo and nocebo effects have been well documented for nearly two centuries. However, research has only relatively recently begun to explicate the neurobiological underpinnings of these phenomena. Similarly, research on the broader social implications of placebo/nocebo effects, especially within healthcare delivery settings, is in a nascent stage. Biological and psychosocial outcomes of placebo/nocebo effects are of equal relevance. A common pathway for such outcomes is the endogenous opioid system. This chapter describes the history of placebo/nocebo in medicine; delineates the current state of the literature related to placebo/nocebo in relation to pain modulation; summarizes research findings related to human performance in sports and exercise; discusses the implications of placebo/nocebo effects among diverse patient populations; and describes placebo/nocebo influences in research related to psychopharmacology, including the relevance of endogenous opioids to new lines of research on antidepressant pharmacotherapies.

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.

Altered physical pain processing in different psychiatric conditions

Several reports indicate either increased or decreased pain sensitivity associated with psychiatric disorders. Chronic pain is highly prevalent in many of these conditions. We reviewed the literature regarding experimental pain sensitivity in patients with major depression, bipolar disorder, posttraumatic stress disorder (PTSD), generalized anxiety disorder, panic disorder, obsessive-compulsive disorder and schizophrenia. Electronic searches were performed to identify studies comparing experimental pain in patients with these conditions and controls. Across 31 depression studies, reduced pain threshold was noted except for ischemic stimuli, where increased pain tolerance and elevated sensitivity to ischemic pain was observed. A more pervasive pattern of low pain sensitivity was found across 20 schizophrenia studies. The majority of PTSD studies (n = 20) showed no significant differences compared with controls. The limited number of bipolar disorder (n = 4) and anxiety (n = 9) studies precluded identification of clear trends. Wide data variability was observed. Awareness of psychiatric patients' pain perception abnormalities is needed for active screening and addressing physical comorbidities, in order to enhance quality of life, life expectancy and mental health.

Effects of visual search task on attentional bias and stress response under pressure

BACKGROUND

it has always been a problem for athletes that their performance is out of order due to pressure in major competitions. The change of attention pattern and the emergence of stress response (SR) caused by negative affect (NA) are the direct reasons for the greater impact on the performance of athletes. It is a hot topic to explore how to improve attention bias (AB) and SR of athletes in stressful situations.

OBJECTIVE

the study aimed to analyze the improvement effect of visual search task (VST) training on AB and SR of athletes under pressure situations.

METHODS

62 male basketball players with national level 2 or above of Shenyang sports institute were divided into experimental group (EG) and control group (CG). Visual search task training program was used in the EG (happy, sad, disgusted, neutral faces) and sham training program was used in the CG (all faces with neutral expression) for two months. Under the stress situation, attention behavior of all subjects before and after training was tested. Physiological coherence and autonomic balance system were used to record heart rate variability synchronously. Parallel frequency domain analysis was divided into very low frequency band (VLF), low frequency (LF), high frequency (HF) and total spectrum (TP). The normalized treatment obtained indexes such as HFnorm, LFnorm, and LF/HF. The e-prime 2.0 software was adopted to obtain the attention bias score. The Positive and Negative Affect Scale (PANAS) and the self-rating stress scale were adopted for evaluation before and after training.

RESULTS

the self-rating pressure in the two groups was lower than that before the training, and the pressure in the experimental group was lower than that in the control group (P < 0.05). After training, the positive emotion of the experimental group was higher than that of the control group, and the EG was lower than that of the CG (P < 0.05). After training, the score of attention bias of happy and neutral faces in the EG was higher than that of theCG, while the score of attention bias of sad and disgusted faces was lower than that of the CG (P < 0.05). After training, LF/HF and LFnorm in the EG were lower than those in the CG, and HFnorm was higher than those in the CG (P < 0.05).

CONCLUSIONS

the training of visual search task can effectively improve the athletes' PA and AB of positive information, reduce the attention bias of negative information and psychological pressure, and relieve theSR.

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

Posttraumatic stress disorder (PTSD) is a known risk factor for the development of chronic pain conditions, and almost 1 in 5 individuals with chronic pain fulfills the criteria for PTSD. However, the relationship between PTSD and pain is poorly understood and studies on pain perception in patients with PTSD show inconsistent results suggesting that different sensory profiles exist among individuals with PTSD. Here, we (1) systematically summarize the current literature on experimentally evoked pain perception in patients with PTSD compared to subjects without PTSD, and (2) assess whether the nature of the traumatic event is associated with different patterns in pain perception. The main outcome measures were pain threshold, pain tolerance, and pain intensity ratings as well as measures of temporal summation of pain and conditioned pain modulation. A systematic search of MEDLINE, EMBASE, Web of Science, PsycINFO, and CINAHL identified 21 studies for the meta-analysis, including 422 individuals with PTSD and 496 PTSD-free controls. No main effect of PTSD on any outcome measure was found. However, stratification according to the nature of trauma revealed significant differences of small to medium effect sizes. Combat-related PTSD was associated with increased pain thresholds, whereas accident-related PTSD was associated with decreased pain thresholds. No clear relationship between PTSD and experimentally evoked pain perception exists. The type of trauma may affect pain thresholds differently indicating the presence of different subgroups with qualitative differences in pain processing.

Time Course of Attention Interruption After Transient Pain Stimulation

Although pain has been shown to affect attentional performance, little is known about the time course of attention interruption after pain stimulus perception. The present study examined the time course of the effects of transient heat pain stimulation on 2 components of attention. Three groups of subjects performed attention tasks under pain, warmth, and no-stimulation control conditions, respectively. The pain and warmth groups received brief physical stimulation. Attention tasks were presented 0 ms, 250 ms, 750 ms, or 1500 ms after the end of stimulation. The 2 attention tasks, namely the spatial cue task (Experiment 1, N = 92) and a Stroop task (Experiment 2, N = 86), were conducted separately. In Experiment 1, attentional orientation of the pain and warmth groups was significantly impaired for at least 1.5 seconds after the physical stimulation had ended. Interestingly, this effect lasted longer for the warmth group than for the pain group. In Experiment 2, pain stimulation had no effect on executive attention at any time. We concluded that attentional orientation is selectively disrupted by both pain and warmth stimuli, but recovers earlier from pain. PERSPECTIVE: This article is concerned with the subsequent interruptive effect of pain on attentional orientation and executive attention by using the spatial cue task and the Stroop task, respectively. These measures offer options for investigating the time course of attention interruption after transient pain stimulation.

Pain from torture: assessment and management

INTRODUCTION

Survivors of torture are for many reasons at particularly high risk for inadequate assessment and management of pain. Among the many health problems associated with torture, persistent pain is frequent, particularly pain in the musculoskeletal system. The pathophysiology underlying post-torture pain is largely unknown, but pain inflicted in torture may have profound effects on neurophysiology and pain processing.

METHODS

A narrative review of assessment and treatment studies, informed by clinical experience, was undertaken.

RESULTS

The clinical presentation in survivors of torture shares characteristics with other chronic primary pain syndromes, including chronic widespread pain. Unfortunately, such pain is often misunderstood and dismissed as a manifestation of psychological distress, both in specialist psychosocially oriented torture services and in mainstream health care. This means that pain is at risk of not being recognized, assessed, or managed as a problem in its own right.

CONCLUSIONS

The available research literature on rehabilitation for torture survivors is predominantly targeted at mental health problems, and studies of effectiveness of pain management in torture survivors are lacking. Rehabilitation is identified as a right in the UN Convention on Torture, aiming to restore as far as possible torture survivors' health and capacity for full participation in society. It is therefore important that pain and its consequences are adequately addressed in rehabilitative efforts. This article summarizes the current status on assessment and management of pain problems in the torture survivor.