An Integrative Review of the Influence of Expectancies on Pain

Initial validation of the expectancies for Benzodiazepine Analgesia Scale

Chronic pain populations exhibit greater prevalence of benzodiazepine (BZD) prescription (vs. the general population) and greater likelihood of BZD use not as prescribed and dependence symptoms. Individuals report taking BZDs for pain relief, potentially contributing to maintenance/escalation of BZD use and hazardous couse with prescription opioids. Identifying cognitive factors underlying pain-BZD use relations represents a critical step toward understanding the role of pain in BZD use trajectories. Outcome expectancies for substance-related analgesia have been implicated in pain-substance use comorbidity (e.g., alcohol), and there is reason to believe these processes may extend to BZD use. The present study aimed to examine psychometric properties of a newly adapted Expectancies for Benzodiazepine Analgesia (EBA) scale and probe associations between EBA scores and prescription opioid use behaviors. Participants were 306 adults (38.9% females) endorsing chronic pain and current BZD prescription who completed an online survey. Results provided initial support for psychometric validity of the EBA: evidence of single-factor structure with good model fit (Bollen-Stine bootstrap p = .101), excellent internal consistency (α = .93), and evidence of concurrent validity via correlations with pain variables, likelihood of BZD use not as prescribed, BZD dependence symptoms, and self-reported BZD use for pain relief. Exploratory findings among participants prescribed opioids indicated positive covariation between EBA scores and behaviors associated with higher risk opioid use. This is, to our knowledge, the first study to assess analgesia expectancies for BZD use. BZD analgesic expectancies warrant further study as a treatment target in comorbid pain and BZD use. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Nocebo hyperalgesia and other expectancy-related factors in daily fibromyalgia pain: Combining experimental and electronic diary methods

OBJECTIVE

Expectancies are known to shape pain experiences, but it remains unclear how different types of expectancies contribute to daily pain fluctuations in fibromyalgia. This combined experimental and diary study aims to provide insights into how experimentally-derived nocebo hyperalgesia and other, diary-derived, expectancy-related factors are associated with each other and with daily pain in fibromyalgia.

METHODS

Forty-one female patients with fibromyalgia first participated in a lab procedure measuring nocebo hyperalgesia magnitude, then filled out an electronic diary 3 times a day over 3 weeks regarding the expectancy-related factors of pain expectancy, anxiety, optimism, and pain-catastrophizing thoughts, and current pain intensity.

RESULTS

Our results indicate that experimentally-induced nocebo hyperalgesia was not significantly related to diary-assessed expectancy-related factors and did not predict daily fibromyalgia pain. Higher levels of the self-reported expectancy-related factors pain expectancy and pain catastrophizing, but not anxiety and optimism, predicted moment-to-moment pain increases in fibromyalgia, after controlling for current pain, moment-of-day and all other expectancy-related factors.

CONCLUSION

Our exploratory research findings indicate that self-reported expectancy-related factors, particularly pain expectancy and pain catastrophizing, are potentially more relevant for predicting daily pain experience than experimentally-induced nocebo hyperalgesia. Further translation of nocebo hyperalgesia is needed from experimental to Ecological Momentary Assessment research. Our findings imply that targeting the decrease in pain expectancy and catastrophizing thoughts e.g., via Cognitive Behavioral Therapy, have potential for improving daily pain levels in fibromyalgia.

Expectations underlie the effects of unpredictable pain: a behavioral and electroencephalogram study

ABSTRACT

Previous studies on the potential effects of unpredictability on pain perception and its neural correlates yielded divergent results. This study examined whether this may be explained by differences in acquired expectations. We presented 41 healthy volunteers with laser heat stimuli of different intensities. The stimuli were preceded either by predictable low, medium, or high cues or by unpredictable low-medium, medium-high, or low-high cues. We recorded self-reports of pain intensity and unpleasantness and laser-evoked potentials (LEPs). Furthermore, we investigated whether dynamic expectations that evolved throughout the experiment based on past trials were better predictors of pain ratings than fixed (nonevolving) expectations. Our results replicate previous findings that unpredictable pain is higher than predictable pain for low-intensity stimuli but lower for high-intensity stimuli. Moreover, we observed higher ratings for the medium-high unpredictable condition than the medium-low unpredictable condition, in line with an effect of expectation. We found significant interactions (N1, N2) for the LEP components between intensity and unpredictability. However, the few significant differences in LEP peak amplitudes between cue conditions did not survive correction for multiple testing. In line with predictive coding perspectives, pain ratings were best predicted by dynamic expectations. Surprisingly, expectations of reduced precision (increased variance) were associated with lower pain ratings. Our findings provide strong evidence that (dynamic) expectations contribute to the opposing effects of unpredictability on pain perception; therefore, we highlight the importance of controlling for them in pain unpredictability manipulations. We also suggest to conceptualize pain expectations more often as dynamic constructs incorporating previous experiences.

How should uncertainty about upcoming painful procedures be communicated? An experimental study into highly uncertain pain predictions

OBJECTIVE

Uncertainty is unavoidable in the context of painful medical procedures. It is important to investigate the impact of different ways of communicating uncertainty on upcoming pain.

METHODS

In our exploratory study, healthy participants (n = 30) were repeatedly presented with three highly uncertain pain predictions communicated by a hypothetical doctor. A direct statement of high uncertainty ("I don't know") was compared to more indirect predictions (social prediction: "It varies widely among people"; range prediction: "… not painful at all to very highly painful"), followed by individually calibrated electrical stimuli of non-, moderately, or very highly painful intensity.

RESULTS

The direct expression of uncertainty led to the most intense pain sensation (for moderately painful stimuli only), lowest and most certain pain expectations, lowest trust in the hypothetical doctor, and lowest feeling of being well-informed, especially as compared to the social prediction. No differential effects on anxiety were observed.

CONCLUSIONS

Expressing high uncertainty indirectly, with reference to the common experiences of others, may be beneficial for optimizing pain experiences and enhancing patients' trust in a medical professional.

PRACTICE IMPLICATIONS

Our findings inform on how high uncertainty about upcoming pain may impact patient and health outcomes, pointing to some advantages of indirect communication.

The Optimal Learning Cocktail for Placebo Analgesia: A Randomized Controlled Trial Comparing Individual and Combined Techniques

This study investigated for the first time the effects of individual and combined application of 3 learning techniques (verbal suggestions, classical conditioning, and observational learning) on placebo analgesia and extinction. Healthy participants (N = 206) were assigned to 8 different groups in which they were taught through either a verbal suggestion, a conditioning paradigm, a video observing someone, or any combination thereof that a placebo device (inactive transcutaneous electric nerve stimulation [TENS]) was capable of alleviating heat pain, whereas one group did not (control). Placebo analgesia was quantified as the within-group difference in experienced pain when the placebo device was (sham) 'activated' or 'inactivated' during equal pain stimuli, and compared between groups. Placebo analgesia was induced in groups with 2 or 3 learning techniques. Significantly stronger placebo analgesia was induced in the combination of all 3 learning techniques as compared to the individual learning techniques or control condition, underlining the additional contribution of 3 combined techniques. Extinction did not differ between groups. Furthermore, pain expectancies, but not state anxiety or trust, mediated placebo analgesia. Our findings emphasize the added value of combining 3 learning techniques to optimally shape expectancies that lead to placebo analgesia, which can be used in experimental and clinical settings. PERSPECTIVE: This unique experimental study compared the individual versus combined effects of 3 important ways of learning (verbal suggestions, classical conditioning, and observational learning) on expectation-based pain relief. The findings indicate that placebo effects occurring in clinical practice could be optimally strengthened if healthcare providers apply these techniques in combination.

The effect of psychological factors on pain outcomes: lessons learned for the next generation of research

Big data and machine learning techniques offer opportunities to investigate the effects of psychological factors on pain outcomes. Nevertheless, these advances can only deliver when the quality of the data is high and the underpinning causal assumptions are considered. We argue that there is room for improvement and identify some challenges in the evidence base concerning the effect of psychological factors on the development and maintenance of chronic pain. As a starting point, 3 basic tenets of causality are taken: (1) cause and effect differ from each other, (2) the cause precedes the effect within reasonable time, and (3) alternative explanations are ruled out. Building on these tenets, potential problems and some lessons learned are provided that the next generation of research should take into account. In particular, there is a need to be more explicit and transparent about causal assumptions in research. This will lead to better research designs, more appropriate statistical analyses, and constructive discussions and productive tensions that improve our science.

Placebo hypoalgesia induced by operant conditioning: a comparative study on the effects of verbal, token-based, and social rewards and punishers

Operant conditioning was shown to be a mechanism of placebo hypoalgesia; however, only verbal rewards and punishers were applied in the previous study. We aimed to induce placebo hypoalgesia using more clinically relevant consequences: token-based and social. Participants were divided into three experimental groups (with verbal, social, and token-based rewards and punishers); and two control groups (with and without placebo application). During operant conditioning, participants in the experimental groups received thermal stimuli of equal intensity and were rewarded for reporting lower pain and punished for reporting higher pain compared to their pretest pain levels. The control groups did not receive any consequences. Our results revealed placebo hypoalgesia was induced by operant conditioning only in the experimental groups with social and token-based reinforcement, compared to the control groups. The hypoalgesic effect found in the group that received verbal reinforcement did not differ significantly from the control group with the placebo application. Moreover, expectations about upcoming pain intensity were found to be a mediator, and the number of reinforcers received during conditioning was a predictor of placebo hypoalgesia. These findings highlight the potential benefits of incorporating token-based and social consequences for optimizing treatment outcomes in pain management.

Past Adversity Influencing Now (PAIN): perspectives on the impact of temporal language on the persistence of pain

Persistent pain is a significant healthcare issue, often unresponsive to traditional treatments. We argue for incorporating non-biomedical perspectives in understanding pain, promoting more comprehensive solutions. This article explores how language, specifically time-related terms, may affect the persistence (stickiness) of pain. We delve into how language influences one's experience of the world, especially in understanding pain through spatial metaphors. Notably, time perceptions differ across languages and cultures and there is no absolute construct of temporal pain experience. In English, time is viewed linearly as past, present, and future. We introduce a framework called Past Adversity Influencing Now (PAIN) which includes various temporal phases of pain; Past Perfect, Past Imperfect, Present, Future Imperfect, and Future Perfect. We suggest that past negative memories (emotional memory images) can "trap" individuals in a "sticky" pain state. We speculate that the process of diagnosing pain as "chronic" may solidify this "stickiness", drawing from the ancient Greek idea of "logos", where pain communicates a message across time and space needing recognition. Our PAIN framework encourages examining pain through a temporal lens, guiding individuals towards a more positive future.

Nocebo Hyperalgesia in Patients With Fibromyalgia and Healthy Controls: An Experimental Investigation of Conditioning and Extinction Processes at Baseline and 1-Month Follow-up

Nocebo effects are adverse treatment outcomes that are not ascribed to active treatment components. Potentially, their magnitude might be higher in patients with chronic pain compared to healthy controls since patients likely experience treatment failure more frequently. The current study investigated group differences in the induction and extinction of nocebo effects on pressure pain at baseline (N = 69) and 1-month follow-up (N = 56) in female patients with fibromyalgia and matched healthy controls. Nocebo effects were first experimentally induced via classical conditioning combined with instructions on the pain-increasing function of a sham transcutaneous electrical nerve stimulation device, then decreased via extinction. One month later, the same procedures were repeated to explore their stability. Results suggest that nocebo effects were induced in the healthy control group during baseline and follow-up. In the patient group, nocebo effects were only induced during follow-up, without clear group differences. Extinction was only observed during baseline in the healthy control group. Further comparisons of nocebo effects and extinction indicated no significant changes across sessions, possibly suggesting their overall magnitudes were stable over time and across groups. In conclusion, contrary to our expectations, patients with fibromyalgia did not have stronger nocebo hyperalgesia; instead, they might be less responsive to nocebo manipulations than healthy controls. PERSPECTIVE: The current study is the first to investigate group differences in experimentally manipulated nocebo hyperalgesia between chronic pain and healthy populations at baseline and 1-month follow-up. Since nocebo effects are common in clinical settings, their investigation in different populations is essential to explain and minimize their adverse effects during treatment.

The Relationship between Nociceptive Detection Thresholds and Pressure- and Electrical Pain Thresholds: An Explorative Study in Rheumatoid Arthritis Patients

Recently, methods have been developed enabling the characterization of the nociceptive function at the detection threshold level by measuring nociceptive detection thresholds (NDTs), rather than at the level of the pain threshold via pain threshold (PT) measurements. Both NDT and PT measurements aim to characterize (parts of) the nociceptive system. To date it is unclear if, and if so to what extent, the two outcomes relate to one another. In this study, the primary aim is to explore the relationship between the two measures in patients with rheumatoid arthritis (RA). As secondary aim, we explore differences in NDT between these RA patients with age- and sex-matched healthy controls (HC) from a readily existing dataset. In total 46 RA patients have been recruited, whereby the pressure- (PPT; bilaterally at two locations) and electrical (EPT) pain threshold were evaluated, as well as the NDTs. Significant, positive correlations were found between the EPT and PPT (R=0.54-0.60), but not with the NDTs (R≤0.25). As compared to HC, higher NDTs were found in the RA group. As the presence of a statistically significant weak relationship can only be evaluated using a larger sample size, our results indicate that there is no moderate or stronger relation between PT and NDT outcomes. This implicates that the two outcomes are not strongly driven by the same (nociceptive) mechanism(s). Future research into NDTs and what factors and/or mechanisms affect the outcome, could yield relevant insights into how to use and interpret the results of this relatively new method.Clinical Relevance - The evaluation of nociceptive detection thresholds, in isolation or together with conventionally evaluated pain thresholds, might provide valuable and complementary insights into nociceptive (dis)function in man.

The Biology of Placebo and Nocebo Effects on Experimental and Chronic Pain: State of the Art

(1) Background: In recent years, placebo and nocebo effects have been extensively documented in different medical conditions, including pain. The scientific literature has provided strong evidence of how the psychosocial context accompanying the treatment administration can influence the therapeutic outcome positively (placebo effects) or negatively (nocebo effects). (2) Methods: This state-of-the-art paper aims to provide an updated overview of placebo and nocebo effects on pain. (3) Results: The most common study designs, the psychological mechanisms, and neurobiological/genetic determinants of these phenomena are discussed, focusing on the differences between positive and negative context effects on pain in experimental settings on healthy volunteers and in clinical settings on chronic pain patients. Finally, the last section describes the implications for clinical and research practice to maximize the medical and scientific routine and correctly interpret the results of research studies on placebo and nocebo effects. (4) Conclusions: While studies on healthy participants seem consistent and provide a clear picture of how the brain reacts to the context, there are no unique results of the occurrence and magnitude of placebo and nocebo effects in chronic pain patients, mainly due to the heterogeneity of pain. This opens up the need for future studies on the topic.

Local brain oscillations and interregional connectivity differentially serve sensory and expectation effects on pain

Pain emerges from the integration of sensory information about threats and contextual information such as an individual's expectations. However, how sensory and contextual effects on pain are served by the brain is not fully understood so far. To address this question, we applied brief painful stimuli to 40 healthy human participants and independently varied stimulus intensity and expectations. Concurrently, we recorded electroencephalography. We assessed local oscillatory brain activity and interregional functional connectivity in a network of six brain regions playing key roles in the processing of pain. We found that sensory information predominantly influenced local brain oscillations. In contrast, expectations exclusively influenced interregional connectivity. Specifically, expectations altered connectivity at alpha (8 to 12 hertz) frequencies from prefrontal to somatosensory cortex. Moreover, discrepancies between sensory information and expectations, i.e., prediction errors, influenced connectivity at gamma (60 to 100 hertz) frequencies. These findings reveal how fundamentally different brain mechanisms serve sensory and contextual effects on pain.

Recovery expectations can be assessed with single-item measures: findings of a systematic review and meta-analysis on the role of recovery expectations on return-to-work outcomes after musculoskeletal pain conditions

ABSTRACT

The objective of this systematic review is to quantify the association between recovery expectations and return-to-work outcomes in adults with musculoskeletal pain conditions. In addition, this review has the second objective to compare the predictive utility of single-item and multi-item recovery expectation scales on return-to-work outcomes. Relevant articles were selected from Embase, PsycINFO, PubMed, Cochrane, and manual searches. Studies that assessed recovery expectations as predictors of return-to-work outcomes in adults with musculoskeletal pain conditions were eligible. Data were extracted on study characteristics, recovery expectations, return-to-work outcomes, and the quantitative association between recovery expectations and return-to-work outcomes. Risk of bias was assessed using the Effective Public Health Practice Project. Odds ratios were pooled to examine the effects of recovery expectations on return-to-work outcomes. Chi-square analyses compared the predictive utility of single-item and multi-item recovery expectation scales on return-to-work outcomes. Thirty studies on a total of 28,741 individuals with musculoskeletal pain conditions were included in this review. The odds of being work disabled at follow-up were twice as high in individuals with low recovery expectations (OR = 2.06 [95% CI 1.20-2.92] P < 0.001). Analyses also revealed no significant differences in the predictive value of validated and nonvalidated single-item measures of recovery expectations on work disability (χ 2 = 1.68, P = 0.19). There is strong evidence that recovery expectations are associated with return-to-work outcomes. The results suggest that single-item measures of recovery expectations can validly be used to predict return-to-work outcomes in individuals with musculoskeletal pain conditions.

Pain Acceptance Among Retired National Football League Athletes: Implications for Clinical Intervention

Over 80% of National Football League (NFL) retirees experience daily pain. Pain acceptance is an important psychological construct implicated in the intensity of chronic pain, though these findings have not been extended to NFL retirees. Therefore, the current study examined the association between pain acceptance and pain intensity among former NFL athletes. NFL retirees (N = 90) recruited from 2018 to 2019 completed questionnaires that assessed pain, substance use, and NFL career information. Multiple linear regression examined the association between current pain acceptance and pain intensity while adjusting for other risk factors of pain. NFL retirees reported average scores of 33.31 (SD = 10.00), and 2.18 (SD = 2.40) on measures of pain acceptance and pain intensity, respectively. After covariate adjustment, greater pain acceptance (β = -0.538, p < .001) was associated with lower pain intensity. These findings can further inform the behavioral and mental health care of retired NFL athletes.

The effects of cannabidiol and analgesic expectancies on experimental pain reactivity in healthy adults: A balanced placebo design trial

Despite its frequent use for pain relief, no experimental pain research has tested the analgesic effects of cannabidiol (CBD) in humans. The goal of this study was to experimentally test the effects of CBD and expectancies for receiving CBD on human pain reactivity. Using a crossover, 2 × 2 factorial balanced placebo design, drug administration (given inactive substance or given active CBD) and verbal instruction sets (told inactive substance or told active CBD) were experimentally manipulated. Fifteen healthy adults each completed four separate experimental sessions. Participants were randomly assigned to different counterbalanced manipulation conditions at each session: control (told inactive-given inactive); expectancy (told active CBD-given inactive); drug (told inactive-given active CBD); and expectancy + drug (told active CBD-given active CBD). Primary outcomes were pain threshold, tolerance, intensity, unpleasantness, conditioned pain modulation (CPM), and offset analgesia (OA). There was a significant main effect of instructions on OA, such that the OA response was significantly larger when participants were told that they received CBD, regardless of drug content. Pain unpleasantness was significantly reduced in the drug, expectancy, and expectancy + drug conditions, relative to the control condition. The drug and expectancy conditions separately improved CPM, whereas the expectancy + drug and control conditions produced the lowest CPM change scores. We did not detect significant effects for pain threshold, tolerance, or intensity. Our results indicated that separate pain outcomes can be differentially affected by CBD and/or expectancies for receiving CBD. Future investigations of the psychological and pharmacological mechanisms underlying CBD analgesia are warranted. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The Influence of Expectancies on Pain and Function Over Time After Total Knee Arthroplasty

OBJECTIVE

Expectancies have a well-documented influence on the experience of pain, responses to treatment, and postsurgical outcomes. In individuals with osteoarthritis, several studies have shown that expectations predict increased pain and disability after total knee replacement surgery. Despite the growing recognition of the importance of expectancies in clinical settings, few studies have examined the influence of expectancies throughout postsurgical recovery trajectories. The objective of the present study was to examine the role of presurgical expectancies on pain and function at 6-week, 6-month, and 1-year follow-ups after total knee arthroplasty.

DESIGN AND PARTICIPANTS

Data were collected from patients scheduled for total knee arthroplasty 1 week before surgery and then at 6 weeks, 6 months, and 1 year after surgery. Correlational and multivariable regression analyses examined the influence of expectancies on patients' perceptions of pain reduction and functional improvement at each time point. Analyses controlled for age, sex, body mass index, presurgical pain intensity and function, pain catastrophizing, anxiety, and depression.

RESULTS

Results revealed that expectancies significantly predicted pain reduction and functional improvement at 1-year follow-up. However, expectancies did not predict outcomes at the 6-week and 6-month follow-ups. Catastrophizing and depressive symptoms emerged as short-term predictors of postsurgical functional limitations at 6-week and 6-month follow-ups, respectively.

CONCLUSIONS

The results suggest that targeting high levels of catastrophizing and depressive symptoms could optimize short-term recovery after total knee arthroplasty. However, the results demonstrate that targeting presurgical negative expectancies could prevent prolonged recovery trajectories, characterized by pain and loss of function up to 1 year after total knee arthroplasty.

Genome-wide association study of pain sensitivity assessed by questionnaire and the cold pressor test

ABSTRACT

We deployed an online pain sensitivity questionnaire (PSQ) and an at-home version of the cold pressor test (CPT) in a large genotyped cohort. We performed genome-wide association studies on the PSQ score (25,321 participants) and CPT duration (6853). We identified one new genome-wide significant locus associated with the PSQ score, which was located in the TSSC1 (also known as EIPR1 ) gene (rs58194899, OR = 0.950 [0.933-0.967], P -value = 1.9 × 10 -8 ). Although high pain sensitivity measured by both PSQ and CPT was associated with individual history of chronic and acute pains, genetic correlation analyses surprisingly suggested an opposite direction: PSQ score was inversely genetically correlated with neck and shoulder pain ( rg = -0.71), rheumatoid arthritis (-0.68), and osteoarthritis (-0.38), and with known risk factors, such as the length of working week (-0.65), smoking (-0.36), or extreme BMI (-0.23). Gene-based analysis followed by pathway analysis showed that genome-wide association studies results were enriched for genes expressed in the brain and involved in neuronal development and glutamatergic synapse signaling pathways. Finally, we confirmed that females with red hair were more sensitive to pain and found that genetic variation in the MC1R gene was associated with an increase in self-perceived pain sensitivity as assessed by the PSQ.

Interest in Digital Peer-Delivered Interventions and Preferences to Improve Pain Self-Efficacy and Reduce Loneliness amongst Patients with Chronic Pain: A Mixed Methods Co-Design Study (Preprint)

BACKGROUND

Two important factors that prolong and exacerbate chronic noncancer pain (CNCP) and disability are low pain self-efficacy and loneliness. Yet, few interventions have shown long-term sustained improvements in pain self-efficacy, and there are no evidence-based treatments that target social connectedness in people living with CNCP. More effective and accessible interventions designed to target self-efficacy and social connectedness could ease the burden of CNCP.

OBJECTIVE

To co-design accessible interventions to increase pain self-efficacy, social connection, pain-related outcomes, and quality of life, this study explored patients' interest and preferences for digital peer-delivered interventions for CNCP as well as implementation barriers and enablers.

METHODS

This cross-sectional mixed methods study was part of a larger longitudinal cohort study. Adult Australian residents (N=186) with CNCP diagnosed by a medical professional or pain specialist were included. Participants were initially recruited through advertising on professional pain social media accounts and websites. Questions examined whether patients were interested in digital peer-delivered interventions and their preferences for specific features (eg, Newsfeed). Pain self-efficacy and loneliness were assessed using validated questionnaires, and the association between these factors and interest in digital peer-delivered support was explored. Open-ended questions explored implementation barriers, enablers, and suggestions for consideration in intervention design.

RESULTS

There was interest in accessing digital peer-delivered interventions, with almost half of the sample indicating that they would access it if it was available. Those who indicated an interest in digital peer interventions reported both lower pain self-efficacy and greater loneliness than those who were not interested. Intervention content that incorporated education, links to health services and resources, and delivery of support by peer coaches were the most frequently preferred intervention features. Three potential benefits were identified: shared experience, social connection, and shared pain management solutions. Five potential barriers were identified: negative focus on pain, judgment, lack of engagement, negative impact on mental health, privacy and security concerns, and unmet personal preferences. Finally, there were 8 suggestions from participants: moderation of the group, interest subgroups, professional-led activities, psychological strategies, links to professional pain resources, newsletter, motivational content, live streaming, and online meetups.

CONCLUSIONS

Digital peer-delivered interventions were of particular interest to those with CNCP who had lower levels of pain self-efficacy and higher levels of loneliness. Future co-design work could tailor digital peer-delivered interventions to these unmet needs. Intervention preferences and implementation barriers and enablers identified in this study could guide further co-design and the development of such interventions.

Counterconditioning as Treatment to Reduce Nocebo Effects in Persistent Physical Symptoms: Treatment Protocol and Study Design

Persistent physical symptoms have a high prevalence and a large impact for patients and society. To date, treatment effects for these symptoms are often limited. Nocebo effects (i.e., negative outcomes that are not attributable to active treatment components) have a substantial influence on treatment success and can be established via learning through classical conditioning. Therefore, interventions aimed at reducing nocebo effects by means of counterconditioning, in which an alternative association (inhibiting the previous association) is learned, could be a promising method for improving physical symptoms. In experimental studies, counterconditioning has been shown promising in reducing experimentally-induced nocebo effects on pain and itch. Application of counterconditioning procedures to reduce nocebo effects on clinical symptoms has yet to be researched. This paper provides a protocol of a 6-week counterconditioning intervention aimed at reducing nocebo effects and clinical pain in patients with fibromyalgia. A study in patients with fibromyalgia is proposed to examine the feasibility and potential effectiveness of this counterconditioning intervention as a novel treatment method for reducing nocebo effects and generalization to clinical pain symptoms. Results can help design an optimized treatment protocol for reducing nocebo effects, based on the experiences of participants and the first indications of treatment efficacy.

How expectancy violations facilitate learning to cope with pain - An experimental approach

BACKGROUND

Expectations of painful sensations constitute a core feature of chronic pain. An important clinical question is whether such expectations are revised when disconfirming experiences are made (e.g., less pain than expected). This study examined how people adjust their pain expectations when the experience of decreasing pain is expected vs. unexpected.

METHODS

In a novel randomized between-subjects design, a subclinical sample of people who frequently experience pain was provided with painful thermal stimulations. Unbeknownst to participants, the temperature applied was decreased from trial to trial. Based on the experimental instructions provided, this experience of decreasing pain was expected in one condition (expectation-confirmation; n = 34), whereas it was unexpected in another (expectation-disconfirmation; n = 39).

RESULTS

Perceived pain intensity was lower in the expectation-confirmation condition than in the expectation-disconfirmation condition (p = .014, η_p² = 0.083). The expectation-confirmation condition also showed a greater adjustment of their pain expectations than the expectation-disconfirmation condition (p = .046, η_p² = 0.047). Across groups, large expectation violations (i.e., less pain than expected) were associated with increases in pain tolerance and the ability to cope with pain at a one-week follow-up.

CONCLUSIONS

In terms of assimilation, perceived pain intensity was shaped in the direction of pain expectations. The greater adjustment of expectations in the expectation-confirming condition is consistent with a confirmation bias in pain perception. Though participants who experienced large discrepancies between expected and experienced pain were hesitant to adjust their pain expectations immediately, expectation violations increased their ability to cope with pain one week later, suggesting some beneficial longer-term effects of expectation violations.

Beyond Pain Scales: A Critical Phenomenology of the Expression of Pain

In this paper, we discuss the qualitative dimension of painful experiences by exploring the role of imagination and metaphorical association in the conceptualization and expression of pain. We employ an engaged critical-phenomenological approach to offer original analysis influenced by the perspectives of people in pain. The paper is organized into three parts. Part 1 reviews literature on the expression of pain, its communication, and its reception—attending in particular to the emphasis on verbalizing pain in healthcare contexts. We here discuss benefits and limitations of standard methods aimed at facilitating the meaningful expression of pain (such as “pain scales”) from the perspectives of patients and practitioners, respectively. We suggest that these methods might be importantly complemented by facilitating creative expression of painful lived experiences with respect to personal lifeworlds. Part 2 deals with the role of imagination and metaphorical association in making sense of pain. We explore how imagination is a cognitive and affective mode of experiencing the world which plays a crucial role in determining how pain is experienced, as well as helping to make sense of pain figuratively in relation to the lifeworld. In Part 3, we draw from principles of engaged phenomenology to foreground case studies in which projects have been able facilitate the intersubjective expression of pain. These examples demonstrate the value of attending to the contours of painful lifeworlds in their specificity, affording both agency and accessibility in their communication, while remaining mindful of the complex power relations which govern perceived legitimacy and testimony relating to the transformation of pain. The overall paper aims to contribute to literature on qualitative pain research on both theoretical and practical levels. By exploring the expression of pain through phenomenology, we aim to enrich current debate on the qualitative experience of pain. We also seek to critically highlight the socio-political dimensions which frame painful experiences, their expression, their lived significance, and their treatment.

Age progression in hypnosis for pain and fatigue in individuals with disabilities

The purpose of this paper is to describe in detail a specific age progression approach that we use in our clinical practice and clinical trials in interventions including hypnosis for chronic pain and fatigue in individuals with disabilities. Moreover, we present preliminary evidence regarding the effects of the hypnosis sessions that use age progression suggestions compared to hypnosis sessions that provide different suggestions, as well as to sessions that did not include hypnotic procedures. Findings indicate that age progression suggestions for pain management with individuals participating in hypnosis treatment resulted in substantial immediate reductions in pain intensity, which were greater than pain reductions associated with treatments sessions providing pain education or cognitive therapy. In addition, age progression sessions provided to individuals receiving online hypnosis treatment for fatigue resulted in immediate large reductions in fatigue severity. Although the design of these two studies does not allow to report specific or long-term effects of the age progression techniques, findings indicate that including age progression suggestions to hypnosis protocols for pain and fatigue management is effective for reducing the immediate level of both symptoms. The development and continued evaluation of hypnotic interventions that increase or restore hope in, and optimism, for the future has the potential for enhancing the psychosocial well-being and quality of life of individuals with pain and fatigue.

Increasing the Effectiveness of a Physical Activity Smartphone Intervention With Positive Suggestions: Randomized Controlled Trial

Background

eHealth interventions have the potential to increase the physical activity of users. However, their effectiveness varies, and they often have only short-term effects. A possible way of enhancing their effectiveness is to increase the positive outcome expectations of users by giving them positive suggestions regarding the effectiveness of the intervention. It has been shown that when individuals have positive expectations regarding various types of interventions, they tend to benefit from these interventions more.

Objective

The main objective of this web-based study is to investigate whether positive suggestions can change the expectations of participants regarding the effectiveness of a smartphone physical activity intervention and subsequently enhance the number of steps the participants take during the intervention. In addition, we study whether suggestions affect perceived app effectiveness, engagement with the app, self-reported vitality, and fatigue of the participants.

Methods

This study involved a 21-day fully automated physical activity intervention aimed at helping participants to walk more steps. The intervention was delivered via a smartphone-based app that delivered specific tasks to participants (eg, setting activity goals or looking for social support) and recorded their daily step count. Participants were randomized to either a positive suggestions group (69/133, 51.9%) or a control group (64/133, 48.1%). Positive suggestions emphasizing the effectiveness of the intervention were implemented in a web-based flyer sent to the participants before the intervention. Suggestions were repeated on days 8 and 15 of the intervention via the app.

Results

Participants significantly increased their daily step count from baseline compared with 21 days of the intervention (t₁₀₇=−8.62; P<.001) regardless of the suggestions. Participants in the positive suggestions group had more positive expectations regarding the app (B=−1.61, SE 0.47; P<.001) and higher expected engagement with the app (B=3.80, SE 0.63; P<.001) than the participants in the control group. No effects of suggestions on the step count (B=−22.05, SE 334.90; P=.95), perceived effectiveness of the app (B=0.78, SE 0.69; P=.26), engagement with the app (B=0.78, SE 0.75; P=.29), and vitality (B=0.01, SE 0.11; P=.95) were found. Positive suggestions decreased the fatigue of the participants during the 3 weeks of the intervention (B=0.11, SE 0.02; P<.001).

Conclusions

Although the suggestions did not affect the number of daily steps, they increased the positive expectations of the participants and decreased their fatigue. These results indicate that adding positive suggestions to eHealth physical activity interventions might be a promising way of influencing subjective but not objective outcomes of interventions. Future research should focus on finding ways of strengthening the suggestions, as they have the potential to boost the effectiveness of eHealth interventions.

Trial Registration

Open Science Framework 10.17605/OSF.IO/CWJES; https://osf.io/cwjes

Temporal–spectral signaling of sensory information and expectations in the cerebral processing of pain

Pain is not only shaped by sensory information but also by an individual’s expectations. Here, we investigated how commonly analyzed electroencephalography (EEG) responses to pain signal sensory information, expectations, and discrepancies thereof (prediction errors) in the processing of pain. Bayesian analysis confirmed that pain perception was shaped by objective sensory information and expectations. In contrast, EEG responses at different latencies (including the N1, N2, and P2 components) and frequencies (including alpha, beta, and gamma oscillations) were shaped by sensory information but not by expectations. Thus, EEG responses to pain are more involved in signaling sensory information than in signaling expectations or prediction errors. Expectation effects are obviously mediated by other brain mechanisms than the effects of sensory information on pain.

The perception of pain is shaped by somatosensory information about threat. However, pain is also influenced by an individual’s expectations. Such expectations can result in clinically relevant modulations and abnormalities of pain. In the brain, sensory information, expectations (predictions), and discrepancies thereof (prediction errors) are signaled by an extended network of brain areas which generate evoked potentials and oscillatory responses at different latencies and frequencies. However, a comprehensive picture of how evoked and oscillatory brain responses signal sensory information, predictions, and prediction errors in the processing of pain is lacking so far. Here, we therefore applied brief painful stimuli to 48 healthy human participants and independently modulated sensory information (stimulus intensity) and expectations of pain intensity while measuring brain activity using electroencephalography (EEG). Pain ratings confirmed that pain intensity was shaped by both sensory information and expectations. In contrast, Bayesian analyses revealed that stimulus-induced EEG responses at different latencies (the N1, N2, and P2 components) and frequencies (alpha, beta, and gamma oscillations) were shaped by sensory information but not by expectations. Expectations, however, shaped alpha and beta oscillations before the painful stimuli. These findings indicate that commonly analyzed EEG responses to painful stimuli are more involved in signaling sensory information than in signaling expectations or mismatches of sensory information and expectations. Moreover, they indicate that the effects of expectations on pain are served by brain mechanisms which differ from those conveying effects of sensory information on pain.

The Effects of Pain Expectancy and Desire for Pain Relief on the Memory of Pain in Half Trail Marathon Runners

Purpose

It has been shown that the memory of pain induced by running might be underestimated. Our previous study showed the contribution of emotional factors to this process. This study aimed to investigate the cognitive factors that might influence the memory of this type of pain, ie expectancy of pain intensity, expectancy of pain unpleasantness, and desire for pain relief.

Participants and Methods

A total of 49 half-marathon runners rated the intensity and unpleasantness of pain immediately after completing a run and one month later. Participants rated the expected intensity and unpleasantness of the upcoming pain before starting the run, as well as the desire for pain relief after its completion. Those who also participated in the previous edition of the half marathon were asked to recall the pain experienced due to that run.

Results

Participants underestimated remembered pain intensity and unpleasantness. The desire for pain relief mediated the memory of pain intensity (p < 0.05), while expectancy of pain intensity influenced memory of pain intensity (a × b) through its effect on the experienced pain (bootstrapped point estimate = 0.08; 95% CI: 0.02–0.32). The remembered intensity of pain experienced during the previous half marathon affected the current pain experience directly (p < 0.05) or indirectly (a × b) by generating pain-related expectancy (bootstrapped point estimate = 0.11; 95% CI: 0.01–0.46). The cognitive variables did not influence the memory of pain unpleasantness.

Conclusion

The memory of pain induced by sports activity may change due to cognitive factors; however, further research is needed to investigate their role in shaping the memory of the sensory and affective dimensions of pain.

Conditioning to Enhance the Effects of Repetitive Transcranial Magnetic Stimulation on Experimental Pain in Healthy Volunteers

OBJECTIVE

In this proof-of-concept study we sought to explore whether the combination of conditioning procedure based on a surreptitious reduction of a noxious stimulus (SRPS) could enhance rTMS hypoalgesic effects [i.e., increase heat pain threshold (HPT)] and augment intervention expectations in a healthy population.

METHODS

Forty-two healthy volunteers (19-35 years old) were enrolled in a randomized crossover-controlled study and were assigned to one of two groups: (1) SRPS and (2) No SRPS. Each participant received two consecutive sessions of active or sham rTMS over the M1 area of the right hand on two visits (1) active, (2) sham rTMS separated by at least one-week interval. HPT and the temperature needed to elicit moderate heat pain were measured before and after each rTMS intervention on the right forearm. In the SRPS group, conditioning consisted of deliberately decreasing thermode temperature by 3°C following intervention before reassessing HPT, while thermode temperature was held constant in the No SRPS group. Intervention expectations were measured before each rTMS session.

RESULTS

SRPS conditioning procedure did not enhance hypoalgesic effects of rTMS intervention, neither did it modify intervention expectations. Baseline increases in HPT were found on the subsequent intervention session, suggesting variability of this measure over time, habituation or a possible "novelty effect."

CONCLUSION

Using a SRPS procedure in healthy volunteers did not enhance rTMS modulating effects on experimental pain sensation (i.e., HPT). Future studies are therefore needed to come up with a conditioning procedure which allows significant enhancement of rTMS pain modulating effects in healthy volunteers.

Improving consultations for persistent musculoskeletal low back pain in orthopaedic spine settings: an intervention development

BACKGROUND

There is a need to improve consultations between patients with persistent musculoskeletal low back pain and orthopaedic spine clinicians when surgery is not indicated. Poor communication and lack of education about self- management in these consultations have been shown to be associated with increased distress and higher subsequent health care seeking.

AIM

To develop a standardised intervention to improve spine care consultations for patients for whom surgery is not beneficial.

METHOD

The intervention was developed in six stages. The first three stages included: interviews with patients, an interactive workshop with clinicians from a mix of disciplines, and interviews with spine clinicians about their perspective of the recommendations, their perceived difficulties and potential improvements. Information from these stages was synthesised by an expert panel, creating a draft intervention structure and content. The main features of the intervention and the materials developed were then reviewed by patients and spine clinicians. Finally, the research team incorporated the recommended amendments to produce the intervention.

RESULTS

In total, 36 patients and 79 clinicians contributed to the development of the intervention. The final intervention includes three components: a pre-consultation letter with information suggesting that surgery is one possible intervention amongst many, introducing the staff, and alerting patients to bring with them a potted history of interventions tried previously. The intervention includes short online training sessions to improve clinicians' communication skills, during the consultation, in reference to listening skills, validation of patients' pain, and use of appropriate language. Clinicians are also supplied with a list of evidence-based sources for advice and further information to share with patients. Finally, post consultation, a follow up letter includes a short summary of the patients' clinical journey, the results of their examination and tests, and a reminder of recommendations for self-management.

CONCLUSION

The intervention includes aspects around patient education and enhanced clinician skills. It was developed with input from a multitude of stakeholders and is based on patients' perceptions of what they would find reassuring and empowering when surgery is excluded. The intervention has the potential to improve the patients care journey and might lead to changes in practice in spine clinicians.

No Evidence of Altered Reactivity to Experimentally Induced Pain Among Regular Cannabis Users

OBJECTIVES

Recent years have seen an increase in the adoption of cannabinoid medicines, which have demonstrated effectiveness for the treatment of chronic pain. However, the extent to which frequent cannabis use (CU) influences sensitivity to acute pain has not been systematically examined. Such a determination is clinically relevant in light of hypersensitivity to pain associated with prolonged use of other analgesics such as opioids, and reports of increased pain sensitivity to experimentally induced pain during acute cannabis intoxication. This study explored differences in measures of pain intensity and tolerance. The authors hypothesized that individuals who report frequent CU would demonstrate greater experimental pain sensitivity.

MATERIALS AND METHODS

Frequent cannabis users (≥3× per week; n=40) and nonusers (n=40) were compared on pain sensitivity, pain tolerance, and pain intensity in response to a cold-pressor task. Group differences were examined.

RESULTS

Frequent CU was not associated with hyperalgesia as cannabis users and nonusers did not exhibit differences on measures of pain tolerance (t (78)=-0.05; P=0.96), sensitivity (t (78)=-0.83; P=0.41), or intensity (t (78)=0.36; P=0.72).

DISCUSSION

Frequent cannabis users did not demonstrate hyperalgesia. This finding should help to inform evaluations of the relative harms and benefits of cannabis analgesic therapies.

Patient expectations about a clinical diagnostic test may influence the clinician's test interpretation

BACKGROUND

With medical information widely available, patients often have preconceived ideas regarding diagnostic procedures and management strategies.

OBJECTIVES

To investigate whether expectations, such as beliefs about the source of symptoms and knowledge about diagnostic tests, influence pain perception during a clinical diagnostic test.

DESIGN

Cross-sectional study.

METHODS

Pain was induced by intramuscular hypertonic saline infusion in the thenar muscles. In line with sample size calculations, fifteen participants were included. All participants received identical background information regarding basic median nerve biomechanics and basic concepts of differential diagnosis via mechanical loading of painful structures. Based on different explanations about the origin of their induced pain, half of the participants believed (correctly) they had 'muscle pain' and half believed (incorrectly) they had 'nerve pain'. Pain intensity and size of the painful area were evaluated in five different positions of the median nerve neurodynamic test (ULNT1 _MEDIAN). Data were analysed with two-way analyses of variance.

RESULTS

/findings: Changes in pain in the ULNT1 _MEDIAN positions were different between the 'muscle pain' and 'nerve pain' group (p < 0.001). In line with their expectations, the 'muscle pain' group demonstrated no changes in pain throughout the test (p > 0.38). In contrast, pain intensity (p ≤ 0.003) and size of the painful area (p ≤ 0.03) increased and decreased in the 'nerve pain' group consistent with their expectations and the level of mechanical nerve loading.

CONCLUSION

Pain perception during a clinical diagnostic test may be substantially influenced by pain anticipation. Moreover, pain was more aligned with beliefs and expectations than with the actual pathobiological process.

Underpredicting pain: an experimental investigation into the benefits and risks

ABSTRACT

Expectancies can shape pain and other experiences. Generally, experiences change in the direction of what is expected (ie, assimilation effects), as seen with placebo effects. However, in case of large expectation-experience discrepancies, experiences might change away from what is expected (ie, contrast effects). Previous research has demonstrated contrast effects on various outcomes, but not pain. We investigated the effects of strong underpredictions of pain on experienced pain intensity. In addition, we assessed related outcomes including (certainty of) expectations, fear of pain, pain unpleasantness, autonomic responses, and trust. Healthy participants (study 1: n = 81 and study 2: n = 123) received verbal suggestions that subsequent heat stimuli would be moderately or highly painful (correct prediction), mildly painful (medium underprediction; study 2 only), or nonpainful (strong underprediction). Both studies showed that participants experienced less intense pain upon strong underprediction than upon correct prediction (ie, assimilation). Expected pain, fear of pain, and pain unpleasantness were generally also lowered. However, strong underprediction simultaneously lowered certainty of expectations and trust in the experimenter. Study 2 indicated that the effects of strong underprediction vs medium underprediction generally did not differ. Moreover, study 2 provided some indications for reduced heart rate and skin conductance levels but increased skin conductance responses upon strong underprediction. In conclusion, even strong underpredictions of pain can reduce pain (ie, cause assimilation), although not significantly more than medium underpredictions. However, strong underpredictions can cause uncertainty and undermine trust. These findings suggest that healthcare providers may wish to be cautious with providing overly positive information about painful medical procedures.

Pain psychology in the 21st century: lessons learned and moving forward

Background and aims In the spring of 2019, Professor Steven J. Linton, the founder of the Center for Health and Medical Psychology (CHAMP) at Örebro University, Sweden, formally retired. As a tribute to his scholarly work covering decades of influence and inspiration to the field of pain psychology, the research center organized a topical conference titled "Pain in the 21st century: Where do we come from and where are we going?", which resulted in this state-of the-art synthesis. The aim of this declaration is to highlight lessons learned but not in the least is meant to inspire and guide our continued journey forward, developing pain psychology into the 21st century. Methods Several collaborators of Professor Linton have summarized and reflected on the current state-of-the-art of pain psychology from the perspective of his input to the field, as well as on developments from the last years of advancements in pain psychology. Results The topics have been divided into six themed sections covering the fear avoidance model, transdiagnostics, secondary prevention, risk- and protective factors, communication and contextual factors. The sections cover a broad spectrum, from basic experimental studies, integrating emotion and motivational theories into current theoretical models, to applied research on the effect of early interventions as well as sophisticated emotion-focused treatment models for pain patients with concurrent emotional ill-health. Conclusions There have been major advancements within pain psychology research during the last decades, moving the field towards a more comprehensive picture, taking emotional and motivational aspects into account to understand pain sufferers. Although psychologically informed interventions in general mainly focus on the individual, it has been put forward that pain management is highly influenced by the surrounding environment, including communication with health care providers, and the occupational and social context. Implications Professor Steven J. Linton has been at the forefront of pain psychology research during the last decades, and inspired by his work this journey will continue into the 21st century, with the ultimate goal of enhancing the understanding and treatment for all people suffering from persistent and disabling pain.

Predicting health-related quality of life in dialysis patients: Factors related to negative outcome expectancies and social support

OBJECTIVES

Dialysis patients report a low health-related quality of life (HRQOL) due to high disease burden and far-reaching consequences of dialysis treatment. This study examined several cognitive-behavioral and social factors, with a focus on negative outcome expectancies, that might be relevant for HRQOL in end-stage kidney disease (ESKD) patients treated with dialysis.

METHODS

Patients treated with hemodialysis or peritoneal dialysis were recruited from Dutch hospitals and dialysis centers. Patients completed self-report questionnaires at baseline (n = 175) and six months follow-up (n = 130). Multiple regression analyses were performed.

RESULTS

Higher scores on factors related to negative outcome expectancies at baseline, especially helplessness and worrying, and less perceived social support were significantly related to worse HRQOL six months later. When controlling for baseline HRQOL, besides sex and comorbidity, helplessness remained significantly predictive of worse HRQOL six months later, indicating that helplessness is associated with changes in HRQOL over time.

CONCLUSIONS

Negative outcome expectancies and social support are relevant markers for HRQOL and/or changes in HRQOL over time.

PRACTICE IMPLICATIONS

Negative outcome expectancies could be prevented or diminished by enhanced treatment information, an improved patient-clinician relationship, and interventions that promote adaptive and realistic expectations. Additionally, increasing supportive social relationships could be a relevant treatment focus.

Expectancies as predictors of symptom improvement after antimicrobial therapy for persistent symptoms attributed to Lyme disease

INTRODUCTION/OBJECTIVE

Expectancies about symptom improvement or deterioration are reliable predictors of symptom progression and treatment outcomes (symptom resolution or symptomatic improvement) in many (non-)pharmacological studies and treatments. This study examined predictors of symptom improvement after antimicrobial therapy for persistent symptoms attributed to Lyme disease, hypothesizing particularly pre-treatment expectancies regarding symptom improvement to be predictive.

METHODS

A predictive study was performed on pre-treatment and post-treatment individual characteristics, including expectancies, and physical and mental health-related quality of life (HRQoL) from the PLEASE-trial comparing randomized 12-weeks of doxycycline, clarithromycin-hydroxychloroquine, or placebo following 2 weeks of intravenous ceftriaxone. At end-of-treatment (14 weeks after trial start) and follow-up (52 weeks), complete data of 231 and 170 (of initial 280) patients with persistent symptoms temporally related to a history of erythema migrans or otherwise confirmed symptomatic Lyme disease, or accompanied by B. burgdorferi IgG or IgM antibodies, were examined through hierarchical regression analyses.

RESULTS

In addition to pre-treatment HRQoL, pre-treatment expectancies regarding symptom improvement were consistently associated with stronger physical and mental HRQoL improvements at both end-of-treatment and follow-up (95% CI range: .09;.54, p < .01 to .27;.92, p < .001). Post-treatment expectancies regarding having received antibiotics vs. placebo was associated with more HRQoL improvement at end-of-treatment, but not at follow-up (95% CI-range 1.00;4.75, p = .003 to -7.34; -2.22, p < .001).

CONCLUSIONS

The present study shows that, next to pre-treatment functioning, patients' pre-treatment and post-treatment expectancies regarding improvement of persistent symptoms attributed to Lyme disease relate to a more beneficial symptom course. Expectancies of patients may be relevant to explain and potentially improve patient outcomes (e.g., by optimized communication about treatment success).

TRIAL REGISTRATION

ClinicalTrials.gov, NCT01207739 (Registration date: 23-09-2010) Key Points • As there is currently no sufficient symptom resolution or symptomatic improvement for many patients with persistent symptoms attributed to Lyme disease, it is relevant to know which factors determine symptom progression and predict heterogeneity in treatment response. • Next to pre-treatment functioning, expectancies regarding symptom improvement and having received antimicrobial study medication are associated with a more beneficial symptom course after both shorter-term and longer-term antimicrobial treatment. • Expectancies are relevant to consider in treatment studies and may be useful in clinical settings to improve symptom course and treatment outcome (e.g., by optimized communication about treatment success).

Direct and mediated effects of treatment context on low back pain outcome: a prospective cohort study

OBJECTIVES

Contextual components of treatment previously associated with patient outcomes include the environment, therapeutic relationship and expectancies. Questions remain about which components are most important, how they influence outcomes and comparative effects across treatment approaches. We aimed to identify significant and strong contextual predictors of patient outcomes, test for psychological mediators and compare effects across three treatment approaches.

DESIGN

Prospective cohort study with patient-reported and practitioner-reported questionnaire data (online or paper) collected at first consultation, 2 weeks and 3 months.

SETTING

Physiotherapy, osteopathy and acupuncture clinics throughout the UK.

PARTICIPANTS

166 practitioners (65 physiotherapists, 46 osteopaths, 55 acupuncturists) were recruited via their professional organisations. Practitioners recruited 960 adult patients seeking treatment for low back pain (LBP).

PRIMARY AND SECONDARY OUTCOMES

The primary outcome was back-related disability. Secondary outcomes were pain and well-being. Contextual components measured were: therapeutic alliance; patient satisfaction with appointment systems, access, facilities; patients' treatment beliefs including outcome expectancies; practitioners' attitudes to LBP and practitioners' patient-specific outcome expectancies. The hypothesised mediators measured were: patient self-efficacy for pain management; patient perceptions of LBP and psychosocial distress.

RESULTS

After controlling for baseline and potential confounders, statistically significant predictors of reduced back-related disability were: all three dimensions of stronger therapeutic alliance (goal, task and bond); higher patient satisfaction with appointment systems; reduced patient-perceived treatment credibility and increased practitioner-rated outcome expectancies. Therapeutic alliance over task (η_p²=0.10, 95% CI 0.07 to 0.14) and practitioner-rated outcome expectancies (η_p²=0.08, 95% CI 0.05 to 0.11) demonstrated the largest effect sizes. Patients' self-efficacy, LBP perceptions and psychosocial distress partially mediated these relationships. There were no interactions with treatment approach.

CONCLUSIONS

Enhancing contextual components in musculoskeletal healthcare could improve patient outcomes. Interventions should focus on helping practitioners and patients forge effective therapeutic alliances with strong affective bonds and agreement on treatment goals and how to achieve them.

A measure of expectancies for alcohol analgesia: Preliminary factor analysis, reliability, and validity

Rates of alcohol consumption are substantially higher among persons with pain, and recent research has focused on elucidating bidirectional pain-alcohol effects. Expectancies for alcohol analgesia could influence the degree to which alcohol confers acute pain-relieving effects, and may amplify the propensity to respond to pain with drinking behavior. However, no validated measures of expectancies for alcohol analgesia are available. Therefore, we developed a five-item measure of Expectancies for Alcohol Analgesia (EAA), which assesses the perceived likelihood that alcohol will reduce pain. The goal of this project was to examine psychometric properties of the EAA among a sample of 273 current alcohol users with chronic pain (M_age = 32.9; 34% female) who completed an online survey of pain and substance use. Confirmatory factor analysis (CFA) results indicated that the hypothesized single-factor structure of the EAA provided good model fit (Bollen-Stine bootstrap p = .13). The EAA also showed excellent internal consistency (α = 0.97), and scores were positively associated with quantity/frequency of alcohol use, alcohol outcome expectancies, coping-related drinking motives, and pain severity (ps < 0.01). These findings provide initial support regarding the single-factor structure, reliability, and validity of the EAA. Examination of predictive utility and further validation are important next steps.

Two birds with one stone.-Addressing depressive symptoms, emotional tension and worry improves tinnitus-related distress and affective pain perceptions in patients with chronic tinnitus

BACKGROUND

Psychological factors link the co-occurrence of tinnitus-related distress and pain perceptions in patients with chronic tinnitus.

OBJECTIVE

This study examines, if treatment-related changes in these factors ameliorate both tinnitus-related distress and pain perceptions in a sample of patients with chronic tinnitus.

METHODS

N = 1238 patients with chronic tinnitus provided pre- and post-treatment ratings of tinnitus-related distress and affective or sensory pain perceptions alongside measures of depressive symptoms and perceived stress. Treatment comprised an intensive tinnitus-specific multimodal treatment program. Using serial indirect-effects analyses, we examined association patterns between baseline values and change rates of those variables that were found to respond to treatment.

RESULTS

Small effect sizes emerged for changes in tinnitus-related distress, affective (but not sensory) pain perceptions, depressive symptoms, emotional tension and worry. At pre- or post-treatment respectively, baseline values and change rates intercorrelated. Across timepoints, (1) baseline tinnitus-related distress and affective pain perceptions were positively associated with improvements in tinnitus-related distress, affective pain perceptions and depressive symptoms. (2) Baseline depressive symptoms or emotional tension mediated positive associations between baseline tinnitus-related distress and improvement in affective pain perceptions. (3) Change in depressive symptoms mediated the effect of baseline tinnitus-related distress on change in affective pain perceptions-partly through associated change in emotional tension or worry. Mood-independent aspects of emotional tension were negatively associated with improvement in affective pain perceptions.

CONCLUSIONS

Depressive symptoms, emotional tension and worry emerge as key predictors of treatment response and transdiagnostic treatment targets for alleviating tinnitus-related distress and functionally associated affective pain perceptions.

Pain sensitivity and autonomic nervous system parameters as predictors of dry eye symptoms after LASIK

PURPOSE

Differences in pain processing and autonomic function among patients have been implicated in the development of chronic pain after surgery. This study was designed to evaluate whether pain and autonomic metrics predict severity of chronic dry eye (DE) symptoms after LASIK, as there is increasing evidence that DE symptoms may be manifestations of persistent post-operative ocular pain.

METHODS

Secondary analysis of prospective randomized clinical trial. Patients were treated with either pregabalin or placebo. As no significant differences in DE symptoms were detected by treatment allocation at six months, all participants were grouped together for the present analyses. Subjects were evaluated pre-LASIK with regard to evoked pain sensitivity (utilizing quantitative sensory testing), autonomic metrics and DE and ocular pain symptoms (via validated questionnaires). Measures of DE and ocular pain were assessed post-LASIK, and the Dry Eye Questionnaire 5 (DEQ5) score 6-months after surgery was the primary outcome of interest.

RESULTS

43 individuals were randomized to pregabalin (n = 21) or placebo (n = 22). 42 completed the 6-month visit. Several baseline autonomic metrics correlated with 6-month post-operative DEQ5 scores, including lower systolic (r -0.37, p = 0.02) and diastolic blood pressure (r -0.32, p = 0.04). Ocular pain at 6 months was also negatively correlated with blood pressure (r -0.31, p = 0.047). The presence of painful aftersensations was a significant predictor of chronic DE symptoms at 6 months (mean DEQ5 scores: 8.0 ± 1.9 versus 5.0 ± 5.0, p = 0.009).

CONCLUSIONS

Heightened parasympathetic tone and prolonged pain sensitivity measured prior to surgery predicted greater DE symptom severity 6 months after LASIK.

TRIAL REGISTRATION

NCT02701764.

Understanding Pain Catastrophizing: Putting Pieces Together

The present narrative review addresses issues concerning the defining criteria and conceptual underpinnings of pain catastrophizing. To date, the concept of pain catastrophizing has been extensively used in many clinical and experimental contexts and it is considered as one of the most important psychological correlate of pain chronicity and disability. Although its extensive use, we are still facing important problems related to its defining criteria and conceptual understanding. At present, there is no general theoretical agreement of what catastrophizing really is. The lack of a consensus on its definition and conceptual issues has important consequences on the choice of the pain management approaches, defining and identifying problems, and promoting novel research. Clinical and research work in absence of a common theoretical ground is often trivial. It is very surprising that clinical and experimental work has grown extensively in the past years, without a common ground in the form of a clear definition of pain catastrophizing and overview of its conceptual basis. Improving the efficacy and efficiency of pan catastrophizing related treatments requires an understanding of the theoretical construct. So far, most interventions have only demonstrated modest effects in reducing pain catastrophizing. Therefore, clarifying the construct may be an important precursor for developing more targeted and effective interventions, thereby easing some of the burden related to this aspect of pain. In our review, we have extracted and de-constructed common elements that emerge from different theoretical models with the aim to understand the concept of catastrophizing, which components can be modulated by psychological interventions, and the general role in pain processing. The analysis of the literature has indicated essential key elements to explain pain catastrophizing: emotional regulation, catastrophic worry (as repetitive negative thinking), rumination, behavioral inhibition and behavioral activation (BIS/BAS) systems, and interoceptive sensitivity. The present paper attempts to integrate these key elements with the aim to re-compose and unify the concept within a modern biopsychosocial interpretation of catastrophizing.

Biopsychosocial Characteristics of Patients With Chronic Pain Expecting Different Levels of Pain Relief in the Context of Multidisciplinary Treatments

OBJECTIVES

Evidence suggests that patients' expectations predict chronic pain treatment outcomes. Although patients vary in terms of expected pain relief, little is known about individual factors related to such variations. This study aims to investigate how patients with various levels of pain relief expectations differ on the basis of biopsychosocial baseline characteristics in the context of multidisciplinary chronic pain treatment.

MATERIALS AND METHODS

Data from 3110 individuals with chronic pain attending one of 3 multidisciplinary pain treatment centers were considered. Participants completed a self-reported measure of pain relief expectations and provided information pertaining to biological, psychological, and social variables.

RESULTS

A backward stepwise regression helped identify biopsychosocial variables that significantly predicted expected pain relief. Subsequent analyses suggest that patients reporting low, moderate, high, and very high expectations of pain relief differed significantly in terms of pain duration and depressive symptoms. Significant between-group differences were also found with regard to overall physical health, age, sex, and ethnicity.

DISCUSSION

Identifying characteristics related to different levels of pain relief expectations is a fundamental step in generating a more comprehensive understanding of how expectations can be of use in the successful management of chronic pain conditions.

Placebo and nocebo effects for itch and itch-related immune outcomes: A systematic review of animal and human studies

Placebo and nocebo effects can influence somatic symptoms such as pain. For itch and other dermatological symptoms these effects have been far less investigated. This review systematically integrates evidence from both animal (mainly rodents) and human trials on placebo and nocebo effects in itch, itch-related symptoms and conditions of the skin and mucous membranes, and related immune outcomes (e.g., histamine). Thirty-one animal studies, and fifty-five human studies (k = 21 healthy participants, k = 34 patients) were included. Overall, studies consistently show that placebo and nocebo effects can be induced by various methods (e.g., suggestions, conditioning and social cues), despite high heterogeneity across studies. Effects of suggestions were found consistently across subjective and behavioral parameters (e.g., itch and scratching in humans), whereas conditioning was likely to impact physiological parameters under certain conditions (e.g., conditioning of histamine levels in stressed rodents). Brain areas responsible for itch processing were associated with nocebo effects. Future research may investigate how variations in methods impact placebo and nocebo effects, and whether all symptoms and conditions can be influenced equally.

Effects of Music and Relaxation Suggestions on Experimental Pain

Pain is a significant public healthcare challenge. There is growing support for the use of music and suggestive techniques as adjuvant pain treatments. The purpose of this study was to (1) examine the effects of music listening combined with relaxation suggestions compared to music alone and silence on experimental pain, and (2) to explore the potential mechanisms of music-induced analgesia. Sixty-six healthy females were randomized to receive either (1) music plus relaxation suggestions, (2) music alone, or (3) silence. Pain and psychological constructs were assessed following two cold-pressor trials. Between-group comparisons indicated that music and suggestions for relaxation are not superior to music alone for pain. More research is needed to explore the effect of analgesic suggestions in combination with music to further investigate music's potential in clinical pain management.

Let's talk about pain catastrophizing measures: an item content analysis

BACKGROUND

Concerns have been raised about whether self-report measures of pain catastrophizing reflect the construct as defined in the cognitive-behavioral literature. We investigated the content of these self-report measures; that is, whether items assess the construct 'pain catastrophizing' and not other theoretical constructs (i.e., related constructs or pain outcomes) using the discriminant content validity method.

METHOD

Items (n = 58) of six pain catastrophizing measures were complemented with items (n = 34) from questionnaires measuring pain-related worrying, vigilance, pain severity, distress, and disability. Via an online survey, 94 participants rated to what extent each item was relevant for assessing pain catastrophizing, defined as "to view or present pain or pain-related problems as considerably worse than they actually are" and other relevant constructs (pain-related worrying, vigilance, pain severity, distress, and disability).

RESULTS

Data were analyzed using Bayesian hierarchical models. The results revealed that the items from pain-related worrying, vigilance, pain severity, distress, and disability questionnaires were distinctively related to their respective constructs. This was not observed for the items from the pain catastrophizing questionnaires. The content of the pain catastrophizing measures was equally well, or even better, captured by pain-related worrying or pain-related distress.

CONCLUSION

Based upon current findings, a recommendation may be to develop a novel pain catastrophizing questionnaire. However, we argue that pain catastrophizing cannot be assessed by self-report questionnaires. Pain catastrophizing requires contextual information, and expert judgment, which cannot be provided by self-report questionnaires. We argue for a person-centered approach, and propose to rename 'pain catastrophizing' measures in line with what is better measured: 'pain-related worrying'.

Learning to fear pain after observing another's pain: An experimental study in schoolchildren

BACKGROUND

Children of individuals with chronic pain have an increased vulnerability to experience pain problems, possibly through observation of pain in their parents. As pain-related fear (PRF) is a critical factor in the development and maintenance of chronic pain, the current experimental study examined the acquisition of PRF through observational learning and subsequent extinction after first-hand experience of the feared stimulus.

METHODS

Healthy children (8-16 years) observed either their mother or a stranger performing two cold pressor tasks (CPT) filled with coloured water. In a differential conditioning procedure, one colour (CS+) was combined with genuine painful facial expressions and the other colour (CS-) with neutral facial expressions. Following this observation phase, children performed both CPTs (10°C) themselves.

RESULTS

Children expected the CS+ to be more painful than the CS- and they reported being more afraid and hesitant to immerse in the CS+ compared to the CS-. Moreover, this fear was reflected in children's level of arousal in anticipation of CPT performance. This learned association extinguished after performing both CPTs. Effects were not moderated by whether the child observed their mother or a stranger, by the child's pain catastrophizing, trait PRF or trait anxiety. Remarkably, learning effects increased when the child perceived a larger difference between the model's painful and neutral facial expressions.

CONCLUSIONS

This study provides evidence for observational learning of PRF and subsequent extinction in schoolchildren. This acquisition of PRF by observing parental pain may contribute to vulnerabilities in children of parents with chronic pain.

SIGNIFICANCE

Children may acquire pain-related fear by observing pain in others and this learned fear can diminish after first-hand experience. Remarkably, observational learning did not depend on the children's relationship with the model, but it did depend on the intensity of pain that is perceived. A better understanding of the impact of observing (parental) pain may help clarify the intergenerational transmission of risk for pain and inform the development of preventive programs.

Neural and behavioral changes driven by observationally-induced hypoalgesia

Observing successful pain treatment in others can induce anticipatory neural processes that, in turn, relieve pain. Previous studies have suggested that social learning and observation influence placebo hypoalgesia. Here, we used electroencephalography (EEG) to determine the neurophysiological changes associated with pain relief acquired through the observation. Thirty-one participants observed a demonstrator undergo painful heat stimulations paired with a "control" cream and non-painful ones paired with a "treatment" cream, which actually were both Vanicreams. After their observation, the participants then received the same creams and stimulations. We found that the treatment cream led to lower self-reported pain intensity ratings than the control cream. Anticipatory treatment cues elicited smaller P2 in electrodes F1, Fz, FC1, and FCz than the control condition. The P2 component localization indicated a higher current density in the right middle frontal gyrus, a region associated with attentional engagement. In placebo responders, the sensorimotor cortex activity captured in electrodes C3, Cz, and C4 indicated that hypoalgesia was positively correlated with resting state peak alpha frequency (PAF). These results suggest that observationally-induced placebo hypoalgesia may be driven by anticipatory mechanisms that modulate frontal attentional processes. Furthermore, resting state PAF could serve as a predictor of observationally-induced hypoalgesia.

How to prevent, minimize, or extinguish nocebo effects in pain: a narrative review on mechanisms, predictors, and interventions

Possible factors that contribute to nocebo effects on pain are explored. Strategies that can prevent, minimize, or extinguish nocebo effects in clinical settings are suggested.

Nocebo effects, such as side effects due to negative expectations regarding the pain treatment, are a concern for health care providers and come with significant costs. This narrative review focuses on underlying mechanisms and possible factors that contribute to the susceptibility to the nocebo effect on pain and related outcomes and suggests strategies that can prevent, minimize, or extinguish nocebo effects in clinical settings. Nocebo effects are the result of psychological (eg, conditioning, verbal suggestions, and observational learning) and neurobiological (eg, cholecystokinin and dopamine regulation) mechanisms. Evidence from clinical and experimental studies lead to various recommendations and strategies to alter the nocebo effect in order to optimize pain treatments, such as providing patients with enhanced information, optimizing patient–physician communication and relationships, and offering psychoeducation on coping skills in order to manage patient expectations. The current literature from both clinical and experimental studies provides a better understanding of the nocebo effect and possible factors that modulate its strength on treatment outcomes. This allows for the development of evidence-based strategies aimed at the prevention, minimization, and treatment of the nocebo effect in pain conditions and possible other somatic disorders.