Placebo 2.0: the impact of expectations on analgesic treatment outcome

Effects of a preoperative psychological expectation-focused intervention in patients undergoing valvular surgery - the randomized controlled ValvEx (valve patients' expectations) study

BACKGROUND

Many patients experience a reduced quality of life for months after heart surgery. Besides medical factors, psychological factors such as preoperative expectations influence the recovery process. The ValvEx study investigated whether an expectation-focused preoperative intervention before heart valve surgery would (i) improve the postoperative recovery process by reducing illness-related disability and ii) impact secondary outcomes such as increased positive realistic expectations, and reduce preoperative anxiety.

METHODS

N = 89 patients undergoing heart valve surgery were randomized into 1 of 2 groups after a baseline assessment: Standard medical care (SOC) vs SOC plus psychological expectation-focused intervention (EXPECT) on the day of hospital admission. Further assessments were conducted on the evening before surgery, 4 to 6 days and 3 months after surgery. The primary outcome was illness-related disability. Constrained longitudinal data analyses were conducted to analyze the intervention effects, while the need for information was considered as a potential moderator.

RESULTS

No general effects were observed for the EXPECT intervention over time regarding the primary outcome illness-related disability (Pain Disability Index, PDI) and the secondary outcomes (P ≥ .167). The intervention effects were moderated by the individual need for information: Patients with a higher need for information who received the EXPECT intervention were less anxious on the evening before surgery (P = .020, d = 0.314) and less restricted in their quality of life 4 to 6 days after surgery compared to patients who received SOC (P = .005, d = 0.464).

CONCLUSIONS

The ValvEx study is the first multicentre study investigating the expectation-optimizing preoperative intervention in heart valve patients. The implementation of the EXPECT intervention seemed to optimize outcomes after heart valve surgery for certain patients, such as patients with a high need for information. It is possible that there were no direct effects of the EXPECT intervention because the intervention dose was too low. These preliminary findings need to be corroborated by larger multicenter trials. Trial registration The study was preregistered at ClinicalTrials (identifier: NCT04502121, https://clinicaltrials.gov/study/NCT04502121).

Patient-Reported Outcomes With Immediate-Loaded Zygomatic Implant Fixed Rehabilitation in Patients With Edentulous Atrophic Maxilla: A Retrospective Practice-Based Clinical Study

OBJECTIVE

To assess if immediate-loaded zygomatic implant-supported fixed rehabilitation meets the expectations of and satisfies patients with atrophic edentulous maxilla.

METHODS

This study included an analysis of data obtained from the dental records of 22 consecutive patients with atrophic edentulous maxillae who received immediate-loaded zygomatic implant-supported fixed rehabilitation between 2017 and 2020. Patients' expectations and satisfaction scores were recorded on a validated 100-mm visual analog scale (VAS). Data was analysed using descriptive statistics and generalized estimating equations.

RESULTS

The results showed a majority of patients had high expectations (VAS > 90) of the rehabilitation with regard to their general satisfaction (71%), aesthetics (71%), chewing (66%), speech (66%), and influence on social life (81%). At 6 months, a majority of the patients showed high general satisfaction (72%), and high satisfaction with aesthetics (77%), chewing (72%), speech (66%), and social life (72%) (VAS > 90). There was a statistically significant increase in the level of satisfaction with chewing from 2 weeks to 6 months after immediate loading (B = 0.309, SE = 0.138, 95% CI: 0.038, 0.580, p = 0.025). A statistically significant association was found between pre-treatment expectations and satisfaction with the rehabilitation's impact on speech, aesthetics, and social life. The satisfaction levels were not influenced by age and sex. All participants agreed that they would recommend this procedure to their peers.

CONCLUSIONS

The results of this study suggest that immediate-loaded zygomatic implant-supported fixed rehabilitation could meet the expectations and satisfy edentulous patients with atrophic maxilla.

Autonomic correlates of osteopathic manipulative treatment on facial functional mapping: an innovative approach based on thermal imaging

Osteopathic manipulative treatment (OMT) has shown efficacy in various clinical conditions and age groups. Understanding its neurobiological, particularly autonomic, mechanisms of action remain limited. Preliminary studies suggested a parasympathetic effect of OMT, evidenced by heart-rate-variability analysis. A cross-over RCT on healthy adults was conducted to compare OMT with sham therapy. Thirty-seven participants underwent two sessions (OMT and sham), comprising baseline, tactile treatment, and post-touch. Novel thermal imaging data analyses in combination with seed correlation analyses (SCA) were employed to explore the OMT effects on autonomic parameters. Particularly, the sham group exhibited an elevated warming effect on the cheeks, nose, and chin. Inversely, for the OMT group a conspicuous cooling trend in the nose, but not in the cheeks and chin was observed. Considering SCA maps, the intensity of the correlation for nose tip, glabella and GSR seeds showed higher values in the OMT compared to the sham group. The comparative analysis of thermal maps and SCA results represents a significant advancement in our understanding of the physiological mechanisms underlying OMT's effects on autonomic functions. By elucidating specific patterns of temperature change, correlation intensity and specific clusters, this research provides valuable insights for optimizing clinical practice and refining theoretical models of manual therapy.

Generalization and enhancement of the effects of an active placebo nasal spray on sadness

INTRODUCTION

The placebo effect, i.e., the psychobiological response arising from administering an inert treatment, influences various domains, such as pain perception and emotional regulation. Positive framing might enhance this effect. This study tested whether the effect of an active placebo (mimicking drug side effects to enhance treatment credibility) on is generalized between two different contexts of sadness induction and if positive framing of side effects enhances this effect.

METHODS

Ninety-six healthy participants were randomly assigned to one of three groups: Placebo+positive framing (PPF), Placebo+standard information (PSI), or no treatment control (NTC). Participants underwent a sadness induction protocol during an in-person lab session and a 20-min online follow-up at home six hours later. Primary outcome was self-reported sadness, secondary outcome was self-reported side effects.

RESULTS

Both the PPF and PSI groups showed a significant decrease in sadness compared to the NTC group after placebo administration during the lab session (p < 0.001) and at follow-up (p < 0.05). At follow-up, only the PPF group did not experience a significant increase in sadness. Positive framing did not improve side effect tolerability.

LIMITATIONS

Self-reported measures introduce subjective bias. The sample restriction to healthy volunteers limits generalizability. The six-hour period may not capture clinically relevant long-term effects.

CONCLUSIONS

The active placebo nasal spray effectively reduced sadness, with effects persisting for six hours and across different contexts. Positive framing did not enhance side effect tolerability but may have helped maintain effectiveness at follow-up. Further research is needed in clinical populations and to explore long-term effects.

Shaping Treatment Expectation to Optimize Efficacy of Interleukin 17A Antagonist Secukinumab in Psoriasis Patients

Purpose

Patients' treatment expectations significantly influence the effectiveness of medical and pharmacological treatments. This clinical proof-of-concept study aimed to enhance treatment outcomes by targeting positive treatment expectations of psoriasis patients beginning systemic anti-psoriatic therapy with secukinumab, an interleukin (IL)-17A antagonist.

Patients and Methods

We randomly assigned patients to three groups: a treatment as usual (TAU) group receiving the standard 300mg dose of secukinumab, a dose-control (DC) group with 75% dose reduction and an experimental (EXP) group receiving the same reduced dose along with a "cover story" designed to positively influence treatment expectations. We evaluated skin symptoms using the Psoriasis Area and Severity Index (PASI), the Dermatology Life Quality Index (DLQI), perceived itch, mood and plasma IL-17A levels at baseline and at 1, 2, 3, 4, 8, 12, and 16 weeks post intervention.

Results

The study included N = 120 patients (average age = 45.78 years, 34% female). A high baseline expectation level (8.1 of 10 points) was observed across all groups which could not be further increased by the EXP-group's "cover story". The EXP and DC groups did not differ with regard to reaching 75% improvement in PASI scores (PASI75), a DLQI score of 0 or 1 or at least 4 points improvement in itch. Over time, the EXP-group showed a faster decline in PASI scores and anxiety symptoms compared to the DC-group, but less improvement in quality of life. IL-17A levels significantly increased throughout the treatment, with no significant differences between groups despite the 75% dose reduction.

Conclusion

This study demonstrates an attempt to modify patients' treatment expectations to enhance the effectiveness of pharmacological therapy with secukinumab in psoriasis patients. However, verbal suggestion alone did not significantly improve clinical outcomes, suggesting that future studies should explore alternative approaches to leverage placebo effects to the benefit of patients with psoriasis.

Educational needs and preferences of adult patients with acute pain: a mixed-methods systematic review

ABSTRACT

Many patients experience acute pain, which has been associated with numerous negative consequences. Pain education has been proposed as a strategy to improve acute pain management. However, studies report limited effects with educational interventions for acute pain in adults, which can be explained by the underuse of the person-centered approach. Thus, we aimed to systematically review and synthetize current evidence from quantitative, qualitative and mixed-methods studies describing patients' needs and preferences for acute pain education in adults. We searched original studies and gray literature in 7 databases, from January 1990 to October 2023. Methodological quality was assessed with the Mixed Methods Appraisal Tool. A total of 32 studies were included (n = 1847 patients), two-thirds of which were qualitative studies of high methodological quality. Most of the studies were conducted over the last 15 years in patients with postsurgical and posttraumatic pain, identified as White, with a low level of education. Patients expressed the greatest need for education when it came to what to expect in pain intensity and duration, as well how to take the medication and its associated adverse effects. The most frequently reported educational preferences were for in-person education while involving caregivers and to obtain information first from physicians, then by other professionals. This review has highlighted the needs and preferences to be considered in pain education interventions, which should be embedded in an approach cultivating communication and partnership with patients and their caregivers. The results still need to be confirmed with different patient populations.

Patients' Experiences During the Long Journey Before Initiating Migraine Prevention with a Calcitonin Gene-Related Peptide (CGRP) Monoclonal Antibody (mAb)

INTRODUCTION

Migraine is under-diagnosed and under-treated. Many people with migraine do not seek medical care, and those who do may initially receive a different diagnosis and/or be dissatisfied with provided care on their journey before treatment with a CGRP-mAb (calcitonin-gene-related-peptide monoclonal antibody).

METHODS

This is a cross-sectional, self-reported, online survey of subjects in Lilly's Emgality® Patient Support Program in 2022. Questionnaires collected insights into subjects' prior experiences with migraine and interactions with healthcare professionals before receiving CGRP-mAbs.

RESULTS

Of the 250 participants with episodic and 250 with chronic migraine, 90% were female and white with a mean age of 26.2 years (± 11.9) at diagnosis and 40.6 (± 12.0) years at survey enrollment. Many participants (71%) suspected they had migraine before diagnosis, with 31% reluctant to seek help. Of these, approximately one-third were unaware of treatment, did not think that a physician could do anything more for migraine, would not take them seriously, or were reluctant due to a previous unhelpful experience. Participants mainly received information from friends/family (47%) or the internet (28%). Participants initially sought treatment due to an increase in migraine frequency (77%), attacks interfering with work or school (75%), or increased pain intensity (74%). Subjects saw a mean of 4.1 (± 4.3) healthcare providers before migraine diagnosis, and 20% of participants previously received a different diagnosis. Participants reported migraine causes included stress/anxiety/depression (42%), hormonal changes (30%), nutrition (20%), and weather (16%). Acute treatment of migraine included prescription (82%) and over-the-counter (50%) medications, changes in nutrition (62%), adjusting fluid intake (56%), and relaxation techniques (55%). Preventive medications included anticonvulsants (61%), antidepressants (44%), blood pressure-lowering medications (43%), and botulinum toxin A injections (17%). Most discontinuations were due to lack of efficacy or side effects.

CONCLUSION

People with migraine describe reluctance in seeking health care, and misunderstandings seem common especially in the beginning of their migraine journey. Graphical abstract available for this article.

The Power of a Good Word: Enhancing the Efficacy of Analgesics in Clinical Settings

INTRODUCTION

Communication between medical staff and patients about treatment efficacy elicits expectations of benefit and improves treatment outcomes. While demonstrated in multiple studies via different research methodologies, uniform communication protocols have not been adopted in clinical practice. Here, we summarize the results of two sister studies aimed at bridging this gap.

METHODS

Women undergoing C-section (study 1, randomized controlled trial) and patients undergoing general or otolaryngologic surgeries (study 2, control group design) were recruited and assigned to the "regular communication" (RC) or "enhanced communication" (EC) arms. The EC arm received positive information about treatment, while the RC arm received no such information. In both studies, the primary outcome was change in pain intensity; in study 2, an additional outcome was morphine consumption.

RESULTS

Eighty women successfully completed study 1, and 102 patients successfully completed study 2. In both studies, significant time*group interactions were observed (p < 0.001). The analgesic effect was virtually twice as large in the EC arm compared to the RC arm. In study 2, in the last two timepoints of assessment, participants in the EC arm also consumed fewer doses of opioids than participants in the RC arm (p < 0.001). No significant differences were found in vital signs.

CONCLUSIONS

We provide ecological evidence that positive information about treatment significantly decreases pain and opioid consumption during routine clinical care. This study and others could encourage healthcare providers to harness the powerful effects of patients' expectations of benefit to improve analgesics outcomes and, potentially, the outcomes of other symptoms.

INTRODUCTION

Communication between medical staff and patients about treatment efficacy elicits expectations of benefit and improves treatment outcomes. While demonstrated in multiple studies via different research methodologies, uniform communication protocols have not been adopted in clinical practice. Here, we summarize the results of two sister studies aimed at bridging this gap.

METHODS

Women undergoing C-section (study 1, randomized controlled trial) and patients undergoing general or otolaryngologic surgeries (study 2, control group design) were recruited and assigned to the "regular communication" (RC) or "enhanced communication" (EC) arms. The EC arm received positive information about treatment, while the RC arm received no such information. In both studies, the primary outcome was change in pain intensity; in study 2, an additional outcome was morphine consumption.

RESULTS

Eighty women successfully completed study 1, and 102 patients successfully completed study 2. In both studies, significant time*group interactions were observed (p < 0.001). The analgesic effect was virtually twice as large in the EC arm compared to the RC arm. In study 2, in the last two timepoints of assessment, participants in the EC arm also consumed fewer doses of opioids than participants in the RC arm (p < 0.001). No significant differences were found in vital signs.

CONCLUSIONS

We provide ecological evidence that positive information about treatment significantly decreases pain and opioid consumption during routine clinical care. This study and others could encourage healthcare providers to harness the powerful effects of patients' expectations of benefit to improve analgesics outcomes and, potentially, the outcomes of other symptoms.

Neural mechanisms underlying placebo and nocebo effects in tonic muscle pain

Pain is a highly subjective and multidimensional experience, significantly influenced by various psychological factors. Placebo analgesia and nocebo hyperalgesia exemplify this influence, where inert treatments result in pain relief or exacerbation, respectively. While extensive research has elucidated the psychological and neural mechanisms behind these effects, most studies have focused on transient pain stimuli. To explore these mechanisms in the context of tonic pain, we conducted a study using a 15-minute tonic muscle pain induction procedure, where hypertonic saline was infused into the left masseter of healthy participants. We collected real-time Visual Analogue Scale (VAS) scores and functional magnetic resonance imaging (fMRI) data during the induction of placebo analgesia and nocebo hyperalgesia via conditioned learning. Our findings revealed that placebo analgesia was more pronounced and lasted longer than nocebo hyperalgesia. Real-time pain ratings correlated significantly with neural activity in several brain regions. Notably, the putamen was implicated in both effects, while the caudate and other regions were differentially involved in placebo and nocebo effects. These findings confirm that the tonic muscle pain paradigm can be used to investigate the mechanisms of placebo and nocebo effects and indicate that placebo analgesia and nocebo hyperalgesia may have more distinct than common neural bases.

Interdisciplinary pain program participants with high catastrophizing scores improve function utilizing enriched therapeutic encounters and integrative health techniques: a retrospective study

Introduction

Pain catastrophizing describes helplessness, rumination, and magnification of a pain experience. High pain catastrophizing is an independent risk factor for disability, pain severity, inadequate treatment response, chronicity, and opioid misuse. Interdisciplinary pain programs (IPPs) are beneficial and cost-effective for individuals with chronic pain, but their functional impact on individuals with high pain catastrophizing is not well established. The emerging field of placebo studies suggests that patient-provider relationships, positive treatment expectations, and sociobiologically informed care trigger physiological responses that may enhance therapeutic interventions.

Methods

In this retrospective observational cohort study, we compared admission and discharge data for 428 adults with high-impact chronic pain (mean 8.5 years) who completed the Spaulding-Medford Functional Restoration Program (FRP). The interdisciplinary FRP team of physiatrists, behavioral health clinicians, physical therapists, and occupational therapists specializes in evidenced-based conventional rehabilitation, integrative health, and pain psychoeducation via enriched therapeutic encounters, fostering collaboration, validation, trust, self-efficacy, and positive expectations. Clinical outcome measures included the Canadian Occupational Performance Measure (COPM) assessing functional performance (COPM-PS) and satisfaction with function (COPM-SS), the Pain Numeric Rating Scale (NRS), the Pain Catastrophizing Scale (PCS), and the Patient Health Questionnaire-9 (PHQ-9).

Results

FRP participants with clinically elevated catastrophizing at baseline (PCS ≥30, mean PCS 39) achieved statistically significant improvements in function (mean delta -2.09, CHI2 = 15.56, p < 0.001), satisfaction with function (COPM-SS mean delta -2.50, CHI2 = 7.42, p = 0.007), pain (NRS mean delta 2.7), mood (PHQ-9 mean delta 1.87, p = 0.002), and catastrophizing (PCS mean delta 4.16, p < 0.001). Subgroup analysis revealed racial disparities in pain scores, and exploratory analysis showed a trend toward reducing opiate consumption.

Discussion

Despite the known association of adverse outcomes with high catastrophizing, FRP participation was associated with increased productive engagement, reduced pain, reduced maladaptive thought processes, and improved mood. Although causation and efficacy cannot be established from a retrospective design, this is the first study to identify functional improvement in patients with high-impact chronic pain and clinically relevant high pain catastrophizing who participate in an IPP combining conventional and complementary rehabilitation with psychoeducation. These enriched therapeutic encounters may enhance the treatment process by promoting trust, empathy, collaboration, and beneficial reframing of patients' experiences, expectations, and goals.

Inpatient's, therapist's and staff's expectations regarding treatment and their effects on placebo response in the psychiatric ward - results from an add-on oxytocin RCT

OBJECTIVES

Patient's and therapist's expectations are considered an important factor influencing placebo response in experimental and therapeutic settings. Nevertheless, the placebo effects of common neurological facilitators that promote treatment efficacy have not been explored. In the present study we examined the estimations of patients, therapists, and staff members, regarding their treatment type and assessed their influence on the facilitating effects of oxytocin.

METHODS

Patients (N = 87) were randomized and double-blindly allocated to receive either oxytocin or placebo, twice daily for a period of four weeks, as part of a larger randomized, double-blind, placebo-controlled trial. Patient's, therapist's and staff's expectations were assessed based on their estimation of treatment type (agent or placebo). Multilevel modeling and univariate and multivariate regression analysis were performed to assess the effects of patient's, therapist's, and staff's estimations on treatment outcome beyond the effects of treatment type.

RESULTS

Staff's, therapist's, and patient's estimations were significantly associated with treatment outcomes. Nevertheless, only therapist's and patient's estimations significantly predicted improvement beyond actual administration, with therapist's and patient's estimations associated with improvement in trait anxiety (STAI-T, B=-1.80, p < .05, and B=-2.02, p < .05, respectively); therapist's estimations were associated with improvement in general distress (OQ-45, B=-3.71, p < .05), and patient's estimations were associated with symptom relief (HSCL-11, B=-0.13, p < .05). Overall, patient's estimations had a higher relative contribution to treatment success, with standardized coefficients across scales ranging from - 0.06 to -0.26.

CONCLUSIONS

The neurobiological factors that promote treatment success are also influenced by patient's and therapist's expectations. Future studies should consider these effects when examining their impact in inpatient settings.

Dopamine has no direct causal role in the formation of treatment expectations and placebo analgesia in humans

Dopamine-based reward and learning mechanisms have been suggested to contribute to placebo effects. However, the exact role of dopaminergic neurotransmission in their generation and maintenance is still unclear. This study aimed to shed light on the causal role of dopamine in establishing positive treatment expectations, as well as on the magnitude and duration of their effect on pain. To this end, we used an established placebo analgesia paradigm in combination with 2 opposing pharmacological modulations of dopaminergic tone, i.e., the dopamine antagonist sulpiride and the dopamine precursor L-dopa which were both applied in an experimental, double-blind, randomized, placebo-controlled trial with a between-subject design in N = 168 healthy volunteers. The study medication successfully altered dopaminergic tone during the conditioning procedure. Contrary to our hypotheses, the medication did not modulate the formation of positive treatment expectation and placebo analgesia tested 1 day later. Placebo analgesia was no longer detectable on day 8 after conditioning. Using a combined frequentist and Bayesian approach, our data provide strong evidence against a direct dopaminergic influence on the generation and maintenance of placebo effects. Further exploration of the neurochemical mechanisms underlying placebo analgesia remains paramount in the quest to exploit these effects for optimal treatment outcomes. Trial registration: ClinicalTrials.gov German Clinical Trials Register, ID: DRKS00029366, https://drks.de/search/en/trial/DRKS00029366.

The impact of patients' pre-treatment expectations on immunosuppressive treatment outcomes in myasthenia gravis: A pilot correlational study

INTRODUCTION/AIMS

The impact of treatment expectations on active treatment outcomes has not been specifically investigated in neuromuscular disorders. We thus explored in myasthenia gravis (MG) the contribution of patients' pre-treatment expectations combined with an immunosuppressant drug on treatment outcomes.

METHODS

This pilot correlational study involved 17 patients with generalized MG, scheduled to start immunosuppressant azathioprine. At baseline, a healthcare professional administered: (i) the Stanford Expectations of Treatment Scale; (ii) a structured checklist paper form asking patients which side-effects they expected to develop after starting azathioprine, coupled with a standardized framing of statements. Quantitative Myasthenia Gravis (QMG) score and daily dose of concomitant drugs were assessed by neurologists as clinical outcomes. Clinical outcomes and side-effects were re-assessed at 3 and 6 months, and clinical outcomes were monitored at 18 months.

RESULTS

Clinically significant improvement in the QMG scores was achieved at 3 or 6 months. The level of state anxiety appeared to act as moderator of pre-treatment negative expectations (strong, positive, indicative correlation, rs = .733, p = .001). The latter were, in turn, associated with the fulfillment of side-effects that patients expected to develop with the new treatment (moderate, positive, indicative correlation, rs = .699, p = .002). No significant correlation emerged between positive and negative expectations.

DISCUSSION

Our findings show a very quick clinical response and also suggest that patients' expectations and anxiety contributed to treatment outcomes, highlighting the importance of promoting safety messages and education strategies around newly introduced treatments. Future goals include evaluating a larger cohort that includes a matched control group.

Pain, mindfulness, and placebo: a systematic review

Introduction

Pain is a complex phenomenon influenced by psychosocial variables, including the placebo effect. The effectiveness of mindfulness-based interventions (MBIs) for pain has been demonstrated in experimental studies and systematic reviews, but the mechanisms of action are only starting to be established. Whether the expectations of individuals experiencing pain can be manipulated during MBIs remains to be systematically evaluated, and what role placebo effects might play remains to be explored.

Methods

To evaluate the literature analyzing placebo effects in MBIs for pain, we performed a systematic review based on searches conducted in PubMed, Web of Science, and SCOPUS databases. Our search revealed a total of 272 studies, of which only 19 studies were included (10 acute pain and nine chronic pain), considering the inclusion and exclusion criteria related to expectations and placebo effects.

Results

From the 19 included studies, six measured placebo effects only in relation to the pharmacological intervention used in the study and not to an MBI.

Discussion

The results of the few studies that focused on the placebo effects of the MBIs indicate that placebo and expectations play a role in the MBIs' effects on pain. Although expectations and placebo effects are frequently discussed in the context of mindfulness and pain research, these results show that these factors are still not routinely considered in experimental designs. However, the results of the few studies included in this systematic review highlight a clear role for placebo and expectancy effects in the overall effects of MBIs for both acute and chronic pain, suggesting that routine measurement and further consideration in future studies are warranted. Additional research in this fascinating and challenging field is necessary to fully understand the connection between MBIs, placebo/expectations, and their effects on pain relief.

Neural circuit basis of placebo pain relief

Placebo effects are notable demonstrations of mind-body interactions1,2. During pain perception, in the absence of any treatment, an expectation of pain relief can reduce the experience of pain-a phenomenon known as placebo analgesia3-6. However, despite the strength of placebo effects and their impact on everyday human experience and the failure of clinical trials for new therapeutics7, the neural circuit basis of placebo effects has remained unclear. Here we show that analgesia from the expectation of pain relief is mediated by rostral anterior cingulate cortex (rACC) neurons that project to the pontine nucleus (rACC→Pn)-a precerebellar nucleus with no established function in pain. We created a behavioural assay that generates placebo-like anticipatory pain relief in mice. In vivo calcium imaging of neural activity and electrophysiological recordings in brain slices showed that expectations of pain relief boost the activity of rACC→Pn neurons and potentiate neurotransmission in this pathway. Transcriptomic studies of Pn neurons revealed an abundance of opioid receptors, further suggesting a role in pain modulation. Inhibition of the rACC→Pn pathway disrupted placebo analgesia and decreased pain thresholds, whereas activation elicited analgesia in the absence of placebo conditioning. Finally, Purkinje cells exhibited activity patterns resembling those of rACC→Pn neurons during pain-relief expectation, providing cellular-level evidence for a role of the cerebellum in cognitive pain modulation. These findings open the possibility of targeting this prefrontal cortico-ponto-cerebellar pathway with drugs or neurostimulation to treat pain.

How side effects can improve treatment efficacy: a randomized trial

While treatment side effects may adversely impact patients, they could also potentially function as indicators for effective treatment. In this study, we investigated whether and how side effects can trigger positive treatment expectations and enhance treatment outcomes. In this pre-registered trial (DRKS00026648), 77 healthy participants were made to believe that they will receive fentanyl nasal sprays before receiving thermal pain in a controlled experimental setting. However, nasal sprays did not contain fentanyl, rather they either contained capsaicin to induce a side effect (mild burning sensation) or saline (inert). After the first session, participants were randomized to two groups and underwent functional MRI. One group continued to believe that the nasal sprays could contain fentanyl while the other group was explicitly informed that no fentanyl was included. This allowed for the independent manipulation of the side effects and the expectation of pain relief. Our results revealed that nasal sprays with a side effect lead to lower pain than inert nasal sprays without side effects. The influence of side effects on pain was dependent on individual beliefs about how side effects are related to treatment outcome, as well as on expectations about received treatment. Functional MRI data indicated an involvement of the descending pain modulatory system including the anterior cingulate cortex and the periaqueductal gray during pain after experiencing a nasal spray with side effects. In summary, our data show that mild side effects can serve as a signal for effective treatment thereby influencing treatment expectations and outcomes, which is mediated by the descending pain modulatory system. Using these mechanisms in clinical practice could provide an efficient way to optimize treatment outcome. In addition, our results indicate an important confound in clinical trials, where a treatment (with potential side effects) is compared to placebo.

Prehabilitation: The underutilised weapon for chronic pain management

Objective

Prehabilitation encompasses preparatory clinical intervention(s) delivered during the period between diagnosis and treatment commencement. Despite widespread successful usage preoperatively, psychological prehabilitation is neglected in outpatient chronic pain management. Although pain management waitlists are associated with treatment attrition and psychological and physical decline, this time window is underutilised in preventing escalation. Waitlists present an under-explored opportunity to 'prehabilitate' patients waiting for treatment. This topical review aimed to: (1) examine the effectiveness of psychological prehabilitation for pain services; (2) evaluate the psychological and physical decline associated with waiting for pain management; (3) highlight key psychological prehabilitative targets for increasing treatment engagement; (4) promote pain management psychological prehabilitation within personalised pain medicine, building recommendations for future interventions.

Methods

Studies regarding the impact of waitlists and prehabilitation for chronic pain were reviewed.

Results

Findings demonstrated that the psychological constructs of patient expectations, health locus of control, self-efficacy and pain catastrophizing dynamically influence attrition, treatment engagement and outcomes while waiting. These constructs are amenable to change, emphasising their potential utility within a targeted waitlist intervention.

Conclusions

Prehabilitating chronic pain patients towards treatment engagement could circumvent cycles of failed treatment seeking, preventing psychological and physical decline, and reducing healthcare utilisation. Utilising the waitlist to identify psychosocial risk factors (external health locus of control, low self-efficacy and high pain catastrophizing) would identify who requires additional support to prevent increased risk of treatment failure, enhancing personalised care before prescribed treatment is accessed. This review cements the urgent need for pain services to engage proactively with prehabilitation innovation.

Reframing pain: the power of individual and societal factors to enhance pain treatment

The effectiveness of analgesics can be increased if synergistic behavioural, psychological, and pharmacological interventions are provided within a supportive environment.

Working with patients' treatment expectations - what we can learn from homeopathy

The usual homeopathic remedy, "globules," does not contain any pharmacologically active ingredient. However, many patients and practitioners report beneficial effects of homeopathic treatment on various health outcomes. Experimental and clinical research of the last two decades analyzing the underlying mechanisms of the placebo effect could explain this phenomenon, with patients' treatment expectations as the predominant mechanism. Treatment expectations can be optimized through various factors, such as prior information, communication, and treatment context. This narrative review analyses how homeopathy successfully utilizes these factors. Subsequently, it is discussed what evidence-based medicine could learn from homeopathic practice to optimize treatment expectations (e.g., using an empathic, patient-centered communication style, deliberately selecting objects in practice rooms, or using clear treatment rituals and salient contextual stimuli) and thereby treatment effectiveness. Homeopathic remedy does not work beyond the placebo effect but is recommended or prescribed as an active treatment by those who believe in it. Thus, practitioners need to understand the manner in which homeopathy (as an example of inert treatment) works and are advised to reintegrate its underlying effective placebo mechanisms into evidence-based medicine. This promises to increase treatment efficacy, tolerability, satisfaction, and compliance with evidence-based treatments, and addresses the desires patients are trying to satisfy in homeopathy in an ethical, fully informed way that is grounded in evidence-based medicine.

Expectancy Effects in Psychedelic Trials

Clinical trials of psychedelic compounds like psilocybin, lysergic acid diethylamide (LSD), and N,N-dimethyltrptamine (DMT) have forced a reconsideration of how nondrug factors, such as participant expectations, are measured and controlled in mental health research. As doses of these profoundly psychoactive substances increase, so does the difficulty in concealing the treatment condition in the classic double-blind, placebo-controlled trial design. As widespread public enthusiasm for the promise of psychedelic therapy grows, so do questions regarding whether and how much trial results are biased by positive expectancy. First, we review the key concepts related to expectancy and its measurement. Then, we review expectancy effects that have been reported in both micro- and macrodose psychedelic trials from the modern era. Finally, we consider expectancy as a discrete physiological process that can be independent of, or even interact with, the drug effect. Expectancy effects can be harnessed to improve treatment outcomes and can also be actively managed in controlled studies to enhance the rigor and generalizability of future psychedelic trials.

Updating beliefs about pain following advice: Trustworthiness of social advice predicts pain expectations and experience

Prior expectations influence pain experience. These expectations, in turn, rely on prior pain experience, but they may also be socially influenced. Yet, most research has focused on self rather than social expectations about pain, and hardly any studies examined their combined effects on pain. Here, we adopted a Bayesian learning perspective to investigate how explicitly communicated social expectations ('advice about pain tolerance') affect own pain expectations, and ultimately pain tolerance, under varying conditions of social epistemic uncertainty (trustworthiness of the advice). N = 72 female participants took part in a coldpressor (cold water) task before (self-learning baseline) and after (socially-influenced learning) receiving advice about their likely pain tolerance from a confederate, the trustworthiness of whom was experimentally manipulated. We used path analysis to test the hypothesis that social advice from a highly trustworthy confederate would influence participants' expectations about pain more than advice from a less trustworthy source, and that the degree of this social influence would in turn predict pain tolerance. We further used a simplified, Bayesian learning, computational approach for explicit belief updating to examine the role of latent parameters of precision optimisation in how participants subsequently changed their future pain expectations (prospective posterior beliefs) based on the combined effect of the confederate's advice on their own pain expectations, and their own task experience. Results confirmed that participants adjusted their pain expectations towards the confederate's advice more in the high- vs. low-trustworthiness condition, and this advice taking predicted their pain tolerance. Furthermore, the confederate's trustworthiness influenced how participants weighted the confederate's advice in relation to their own expectations and task experience in forming prospective posterior beliefs. When participants received advice from a less trustworthy confederate, their own sensory experience was weighted more highly than their socially-influenced prior expectations. Thus, explicit social advice appears to impact pain by influencing one's own pain expectations, but low social trustworthiness leads to these expectations becoming more malleable to novel, sensory learning.

Learning by observing: a systematic exploration of modulatory factors and the impact of observationally induced placebo and nocebo effects on treatment outcomes

Introduction

Observational learning (OL) refers to learning through observing other people's behavior. OL has been suggested as an effective and simple tool to evoke treatment expectations and corresponding placebo and nocebo effects. However, the exact mechanisms by which OL shapes treatment outcomes, its moderating factors and possible areas of application remain unclear. We thus reviewed the existing literature with two different literature searches to answer the following questions: Which influencing factors contribute to OL-induced placebo and nocebo effects (in healthy volunteers and patients) and how large are these effects (search 1)? In which medical fields has OL been used so far to modulate treatment expectancy and treatment outcomes in patients, their caregivers, and at-risk groups (search 2)? We also aimed to explore whether and how the assessment of treatment expectations has been incorporated.

Methods

We conducted two independent and comprehensive systematic literature searches, both carried out on September 20, 2022.

Results

We identified 21 studies that investigated OL-mediated placebo and nocebo effects for pain and itch, the (placebo) efficacy of sham treatment on anxiety, and the (nocebo) induction of medication side effects (search 1). Studies showed that OL can efficiently induce placebo and nocebo effects across different presentation modes, with medium effect sizes on average: placebo effects, d = 0.79 (range: d = -0.36-1.58), nocebo effects, d = 0.61 (range: d = 0.04-1.5). Although several moderating factors have been investigated, their contribution to OL-induced effects remains unclear because of inconsistent results. Treatment expectation was assessed in only four studies. Regarding medical applications of OL (search 2), we found 12 studies. They showed that OL was effectively applied in preventive, therapeutic and rehabilitative interventions and that it was mainly used in the field of psychosomatics.

Discussion

OL effects on treatment outcomes can be both positive and negative. Future research should investigate which individuals would benefit most from OL and how OL can be implemented most effectively to induce placebo and avoid nocebo effects in clinical settings.

Systematic review registration

This work was preregistered at the Center for Open Science as open-ended registration (doi: 10.17605/OSF.IO/FVHKE). The protocol can be found here: https://archive.org/details/osf-registrations-fvhke-v1.

Influence of Role Expectancy on Patient-Reported Outcomes Among Patients With Migraine: A Randomized Clinical Trial

Importance

It is usually assumed that an individual's classification as a patient or a healthy person is determined by the presence or absence of disease, but little is known about whether the mere awareness of being a patient or a healthy control can play an important role for reporting outcomes.

Objective

To investigate whether assignment to the role of a patient or a healthy control has an effect on patient-reported outcomes.

Design, Setting, and Participants

This single center, double-blind, 3-group randomized clinical trial included consecutive patients from a tertiary headache clinic based at a single center in Germany who were invited to participate between October 2019 and June 2023. Statistical analysis was performed from January to March 2024.

Intervention

Patients with migraine were randomized into 2 groups. The first group was told that this study was centered on migraine symptoms, whereas the second group was told that healthy controls were being sought for a study about patients with vertigo. A third group of age- and sex-matched headache-free participants served as controls. All participants viewed 2 standardized roller coaster videos and provided ratings of their perceived levels of motion sickness and dizziness.

Main Outcomes and Measures

The primary outcome was self-reported vestibular symptoms. Secondary outcomes included differences in motion sickness, headache burden, and migraine disability. Outcomes were assessed using standardized questionnaires.

Results

The final sample included 366 participants: 122 patients with migraine assigned the role of patient (MP) (migraine as patient): mean [SD] age, 37.56 [12.93] years; 105 [86.1%] female), 122 patients with migraine assigned the role of healthy participant (MH) (migraine as healthy): mean [SD] age, 37.03 [13.10] years; 107 [87.7%] female), and 122 headache-free controls (HC): mean [SD] age, 37.55 [11.56] years; 100 [82.0%] female). The assigned role of the individuals with migraine (MP vs MH) had a significant effect on self-disclosure of (1) estimation that symptoms (dizziness) will occur under specific conditions (self-reported vestibular symptoms: 79 MP [64.8%]; 29 MH [23.8%]; 9 HC [7.4%]; P < .001), (2) the increase of such symptoms (dizziness) after viewing the roller coaster video, and (3) the reported frequency (median [IQR] self-reported monthly headache days for MP: 7 [4-15] days; for MH: 5 [2-10] days; P = .008) and severity (median [IQR] migraine disability assessment score for MP: 35 [20-64] points; for MH: 25 [11-47] points; P = .005) of migraine symptoms. Statistically significant changes were also found for self-reported headache frequency and disability caused by migraine.

Conclusions and Relevance

This randomized clinical trial found an effect of expectations regarding the role of a patient with respect to clinical and study outcomes. These findings suggest that role expectations should be taken into account when, for example, invasive treatments are discussed.

Trial Registration

ClinicalTrials.gov Identifier: NCT06322550.

Pre-treatment expectations and their influence on subjective symptom change in Crohn's disease

BACKGROUND

Treatment expectations reportedly shape treatment outcomes, but have not been studied in the context of multimodal therapy in Crohn's disease (CD). Therefore, the current study investigated the role of treatment expectations for subjective symptom changes in CD patients who have undergone an integrative multimodal therapy program.

METHODS

Validated questionnaires were completed at the start of the treatment program and post intervention. Pre-treatment expectations and experienced symptom change were assessed with the Generic Rating Scale for Previous Treatment Experiences, Treatment Expectations, and Treatment Effects (GEEE); stress levels were quantified with the Perceived Stress Scale (PSS-10) and disease specific quality of life was quantified with the disease-specific Inflammatory Bowel Disease Questionnaire (IBDQ). We performed multiple linear and Bayesian regression to determine how expectations related to symptom change.

RESULTS

N = 71 CD patients (66.2% female) were included. Stronger expectations regarding symptom improvement (b = 0.422, t = 3.70, p < .001) were associated with higher experienced symptom improvement. Additionally, Bayesian analysis provided strong evidence for including improvement expectations as a predictor of improvement experience (BFinclusion = 13.78).

CONCLUSIONS

In line with research in other disorders, we found that positive treatment expectations were associated with experienced symptom improvement. In contrast, we found no indication that an experience of symptom worsening was associated with positive or negative baseline treatment expectations. Induction of positive expectations might be a potential avenue for improving treatment outcomes in CD therapy.

Open-label placebo treatment does not enhance cognitive abilities in healthy volunteers

The use of so-called 'smart drugs' such as modafinil to improve cognitive performance has recently attracted considerable attention. However, their side effects have limited user enthusiasm. Open-label placebo (OLP) treatment, i.e., inert treatments that are openly disclosed to individuals as having no active pharmacological ingredient, has been shown to improve various medical symptoms and conditions, including those related to cognitive performance. OLP treatment could therefore be an exciting alternative to pharmacological cognitive enhancers. Here, we used a randomized-controlled design to investigate the effect of a 21-day OLP treatment on several sub-domains of cognitive performance in N = 78 healthy volunteers. Subjective and objective measures of cognitive performance as well as different measures of well-being were obtained before and after the treatment period. Using a combination of classic Frequentist and Bayesian analysis approaches showed no additional benefit from OLP treatment in any of the subjective or objective measures of cognitive performance. Our study thus highlights possible limitations of OLP treatment in boosting cognitive performance in healthy volunteers. These findings are discussed in the light of expectancy-value considerations that may determine OLP efficacy.

The influence of psychological traits and prior experience on treatment expectations

BACKGROUND

Placebo and nocebo responses are modulated by the treatment expectations of participants and patients. However, interindividual differences predicting treatment expectations and placebo responses are unclear. In this large-scale pooled analysis, we aim to investigate the influence of psychological traits and prior experiences on treatment expectations.

METHODS

This paper analyses data from six different placebo studies (total n = 748). In all studies, participants' sociodemographic information, treatment expectations and prior treatment experiences and traits relating to stress, somatization, depression and anxiety, the Big Five and behavioral inhibition and approach tendencies were assessed using the same established questionnaires. Correlation coefficients and structural equation models were calculated to investigate the relationship between trait variables and expectations.

RESULTS

We found small positive correlations between side effect expectations and improvement expectations (r = 0.187), perceived stress (r = 0.154), somatization (r = 0.115), agitation (r = 0.108), anhedonia (r = 0.118), and dysthymia (r = 0.118). In the structural equation model previous experiences emerged as the strongest predictors of improvement (β = 0.32, p = .005), worsening (β = -0.24, p = .005) and side effect expectations (β = 0.47, p = .005). Traits related to positive affect (β = - 0.09; p = .007) and negative affect (β = 0.04; p = .014) were associated with side effect expectations.

DISCUSSION

This study is the first large analysis to investigate the relationship between traits, prior experiences and treatment expectations. Exploratory analyses indicate that experiences of symptom improvement are associated with improvement and worsening expectations, while previous negative experiences are only related to side effect expectations. Additionally, a proneness to experience negative affect may be a predictor for side effect expectation and thus mediate the occurrence of nocebo responses.

Placebo and nocebo effects and mechanisms associated with pharmacological interventions: an umbrella review

OBJECTIVES

This review aimed to summarise the existing knowledge about placebo and nocebo effects associated with pharmacological interventions and their mechanisms.

DESIGN

Umbrella review, adopting the Assessment of Multiple Systematic Reviews 2 tool for critical appraisal.

DATA SOURCES

MEDLINE/PubMed, Scopus, Web of Science, PsycINFO, Cochrane Central Register of Controlled Trial were searched in September 2022, without any time restriction, for systematic reviews, narrative reviews, original articles. Results were summarised through narrative synthesis, tables, 95% CI.

OUTCOME MEASURES

Mechanisms underlying placebo/nocebo effects and/or their effect sizes.

RESULTS

The databases search identified 372 studies, for a total of 158 312 participants, comprising 41 systematic reviews, 312 narrative reviews and 19 original articles. Seventy-three per cent of the examined systematic reviews were of high quality.Our findings revealed that mechanisms underlying placebo and/or nocebo effects have been characterised, at least in part, for: pain, non-noxious somatic sensation, Parkinson's disease, migraine, sleep disorders, intellectual disability, depression, anxiety, dementia, addiction, gynaecological disorders, attention-deficit hyperactivity disorder, immune and endocrine systems, cardiovascular and respiratory systems, gastrointestinal disorders, skin diseases, influenza and related vaccines, oncology, obesity, physical and cognitive performance. Their magnitude ranged from 0.08 to 2.01 (95% CI 0.37 to 0.89) for placebo effects and from 0.32 to 0.90 (95% CI 0.24 to 1.00) for nocebo effects.

CONCLUSIONS

This study provides a valuable tool for clinicians and researchers, identifying both results ready for clinical practice and gaps to address in the near future.

FUNDING

Università Cattolica del Sacro Cuore, Milan, Italy with the 'Finanziamento Ponte 2022' grant.

PROSPERO REGISTRATION NUMBER

CRD42023392281.

Study protocol: effects of treatment expectation toward repetitive transcranial magnetic stimulation (rTMS) in major depressive disorder-a randomized controlled clinical trial

BACKGROUND

Patients' expectations toward any given treatment are highly important for the effectiveness of such treatment, as has been demonstrated for several disorders. In particular, in major depressive disorder (MDD), one of the most frequent and most serious mental disorders with severe consequences for the affected, the augmentation of available treatment options could mean a ground-breaking success. Repetitive transcranial magnetic stimulation (rTMS), a new, non-invasive, and well-tolerated intervention with proven effects in the treatment of MDD, appears particularly suitable in this context as it is assumed to exert its effect via structures implicated in networks relevant for both expectation and depression.

METHODS

All patients will receive rTMS according to its approval. Half of the patients will be randomized to a psychological intervention, which is a comprehensive medical consultation aiming to improve positive treatment expectations; the control group will receive a conventional informed consent discussion (in the sense of a treatment-as-usual condition). As outcome parameters, instruments for both self-assessment and external assessment of depression symptoms will be applied. Furthermore, psycho-immunological parameters such as inflammation markers and the cortisol awakening response in saliva will be investigated. Resting-state functional magnetic resonance imaging (rs fMRI) will be performed to analyze functional connectivity, including the cerebellum, and to identify neuronal predictors of expectation effects. In addition, possible cerebellar involvement will be assessed based on a cerebellar-dependent motor learning paradigm (i.e., eyeblink conditioning).

DISCUSSION

In this study, the effects of treatment expectations towards rTMS are investigated in patients with MDD. The aim of this study is to identify the mechanisms underlying the expectation effects and, beyond that, to expand the potential of non-invasive and well-tolerated treatments of MDD.

TRIAL REGISTRATION

German Registry of Clinical Studies (DRKS DRKS00028017. Registered on 2022/03/07. URL: https://www.drks.de/drks_web/ .

The role of the communicated treatment rationale on treatment outcome: study protocol for a randomized controlled trial

BACKGROUND

Placebo effects are a well-established phenomenon in the treatment of depression. However, the mechanism underlying these effects are not fully understood. Treatment expectations are considered one explanation for why placebos work. Treatment expectations are likely to be affected by clinician-patient interactions. This study aims to investigate the role of the communicated treatment rationale in modulating treatment expectations and its effects on the treatment outcomes of a pharmacological and a psychological active placebo intervention for depression. In this study, treatment expectations are modulated by presenting illness models that are either congruent or incongruent with the treatment intervention that follows.

METHODS

This 2 × 2 randomized controlled trial will involve patients with major depression. Participants will either receive a biological or a psychological illness model from a clinician. Following this, they are randomly assigned to receive either a pharmacological or a psychological active placebo intervention. The illness model and the treatment are either congruent or incongruent with each other, resulting in four groups. In addition, a natural course control group will be included.

DISCUSSION

This study will provide insights into the mechanism of expectation modulation in active placebo treatments for major depression. The results may provide insights for clinicians to improve their communication with patients by focusing on treatment expectations. By identifying the factors that contribute to placebo effects, this study has the potential to improve the effectiveness of existing depression treatments and reduce the burden of this highly prevalent mental health condition.

TRIAL REGISTRATION

This trial has been registered prospectively at ClinicalTrials.gov under the identifier: NCT04719663. Registered on January 22, 2021.

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.

Expectation focused and frequency enhanced cognitive behavioural therapy for patients with major depression (EFFECT): a study protocol of a randomised active-control trial

INTRODUCTION

The effectiveness of psychotherapy in depression is subject of an ongoing debate. The mechanisms of change are still underexplored. Research tries to find influencing factors fostering the effect of psychotherapy. In that context, the dose-response relationship should receive more attention. Increasing the frequency from one to two sessions per week seems to be a promising start. Moreover, the concept of expectations and its influence in depression can be another auspicious approach. Dysfunctional expectations and the lack of their modification are central in symptom maintenance. Expectation focused psychological interventions (EFPI) have been investigated, primarily in the field of depression. The aim of this study is to compare cognitive behavioural therapy (CBT) once a week with an intensified version of CBT (two times a week) in depression as well as to include a third proof-of-principle intervention group receiving a condensed expectation focused CBT.

METHODS AND ANALYSIS

Participants are recruited through an outpatient clinic in Germany. A current major depressive episode, diagnosed via structured clinical interviews should present as the main diagnosis. The planned randomised-controlled trial will allow comparisons between the following treatment conditions: CBT (one session/week), condensed CBT (two sessions/week) and EFPI (two sessions/week). All treatment arms include a total dose of 24 sessions. Depression severity applies as the outcome variable (Beck Depression Inventory II, Montgomery Asberg Depression Rating Scale). A sample size of n=150 is intended.

ETHICS AND DISSEMINATION

The local ethics committee of the Department of Psychology, Philipps-University Marburg approved the study (reference number 2020-68 v). The final research article including the study results is intended to be published in international peer-reviewed journals.

TRIAL REGISTRATION NUMBER

German Clinical Trials Registry (DRKS00023203).

No long-term effects after a 3-week open-label placebo treatment for chronic low back pain: a 3-year follow-up of a randomized controlled trial

ABSTRACT

Chronic low back pain is prevalent, highly disabling, and a relevant socioeconomic health concern. Although allocated to placebo groups, patients in randomized controlled trials show significant pain relief, pointing to the relevance of placebo effects. Overcoming ethical and legal concerns related to deceptive placebos, recent studies have demonstrated the efficacy of short-term treatments for chronic low back pain with open-label (ie, nondeceptive) placebos. However, data on long-term efficacy of open-label placebos are sparse. Here, we report a 3-year follow-up of our previously published randomized controlled trial demonstrating pain reduction, improvement in disability, and depressive symptoms after a 3-week treatment with open-label placebos. Including records from 89 previously enrolled patients, we investigated changes between the groups with and without previous open-label placebo treatment in pain intensity (primary outcome), disability and mood (secondary outcomes), biopsychosocial factors and lifestyle (exploratory outcomes) from parent baseline to follow-up. Over the 3-year period, there were no differences in any outcome between groups with and without open-label placebo treatment. Therefore, our follow-up data do not support the previously suggested assumption that a 3-week open-label placebo treatment has long-term effects. This study was preregistered on April 14, 2020, in the German Clinical Trials Register (registration number DRKS00021405).

Conscious connected breathing with breath retention intervention in adults with chronic low back pain: protocol for a randomized controlled pilot study

BACKGROUND

Chronic pain is a major source of human suffering, and chronic low back pain (cLBP) is among the most prevalent, costly, and disabling of pain conditions. Due to the significant personal and societal burden and the complex and recurring nature of cLBP, self-management approaches that can be practiced at home are highly relevant to develop and test. The respiratory system is one of the most integrated systems of the body, and breathing is bidirectionally related with stress, emotion, and pain. Thus, the widespread physiological and psychological impact of breathing practices and breathwork interventions hold substantial promise as possible self-management strategies for chronic pain. The primary aim of the current randomized pilot study is to test the feasibility and acceptability of a conscious connected breathing with breath retention intervention compared to a sham control condition.

METHODS

The rationale and procedures for testing a 5-day conscious connected breathing with breath retention intervention, compared to a deep breathing sham control intervention, in 24 adults (18-65 years) with cLBP is described. Both interventions will be delivered using standardized audio recordings and practiced over 5 days (two times in-person and three times at-home), and both are described as Breathing and Attention Training to reduce possible expectancy and placebo effects common in pain research. The primary outcomes for this study are feasibility and acceptability. Feasibility will be evaluated by determining rates of participant recruitment, adherence, retention, and study assessment completion, and acceptability will be evaluated by assessing participants' satisfaction and helpfulness of the intervention. We will also measure other clinical pain, psychological, behavioral, and physiological variables that are planned to be included in a follow-up randomized controlled trial.

DISCUSSION

This will be the first study to examine the effects of a conscious connected breathing with breath retention intervention for individuals with chronic pain. The successful completion of this smaller-scale pilot study will provide data regarding the feasibility and acceptability to conduct a subsequent trial testing the efficacy of this breathing self-management practice for adults with cLBP.

TRIAL REGISTRATION

Clinicaltrials.gov, identifier NCT04740710 . Registered on 5 February 2021.

Pain, from perception to action: A computational perspective

Pain is driven by sensation and emotion, and in turn, it motivates decisions and actions. To fully appreciate the multidimensional nature of pain, we formulate the study of pain within a closed-loop framework of sensory-motor prediction. In this closed-loop cycle, prediction plays an important role, as the interaction between prediction and actual sensory experience shapes pain perception and subsequently, action. In this Perspective, we describe the roles of two prominent computational theories-Bayesian inference and reinforcement learning-in modeling adaptive pain behaviors. We show that prediction serves as a common theme between these two theories, and that each of these theories can explain unique aspects of the pain perception-action cycle. We discuss how these computational theories and models can improve our mechanistic understandings of pain-centered processes such as anticipation, attention, placebo hypoalgesia, and pain chronification.

[Placebo effects in analgesia : Influence of expectations on the efficacy and tolerability of analgesic treatment]

Expectations of patients influence the perception and neuronal processing of acute and chronic pain and modulate the effectiveness of analgesic treatment. The expectation of treatment is not only the most important determinant of placebo analgesia. Expectations of treatment also influence the efficacy and tolerability of "active" pharmacological and non-pharmacological treatment of pain. Recent insights into the psychological and neurobiological mechanisms underlying the clinically relevant effects of treatment expectations enable and call for the systematic integration and modulation of treatment expectations into analgesic treatment concepts. Such a strategy promises to optimize analgesic treatment and to prevent or reduce the burden of unwanted side effects and the misuse of analgesics, particularly of opioids. This review highlights the current concepts, recent achievements and also challenges and key open research questions.

Placebo and nocebo effects: from observation to harnessing and clinical application

Placebo and nocebo effects are salubrious benefits and negative outcomes attributable to non-specific symbolic components. Leveraging advanced experimental and analytical approaches, recent studies have elucidated complicated neural mechanisms that may serve as a solid basis for harnessing the powerful self-healing and self-harming capacities and applying these findings to improve medical practice and minimize the unintended exacerbation of symptoms in medical practice. We review advances in employing psychosocial, pharmacological, and neuromodulation approaches to modulate/harness placebo and nocebo effects. While these approaches show promising potential, translating these research findings into clinical settings still requires careful methodological, technical, and ethical considerations.

Personalised exercise therapy and self-management support for people with multimorbidity: Development of the MOBILIZE intervention

BACKGROUND

To our knowledge, there is no intervention which includes personalised exercise therapy and self-management support for people with multimorbidity, although these interventions may be as effective as for people with single chronic conditions. Therefore, we developed a novel intervention, including personalised exercise therapy and self-management support for people with multimorbidity.

METHODS

We followed the Medical Research Council framework and conducted one scoping review, five systematic reviews, two registry-based studies, one qualitative interview study and a mixed-methods feasibility study. Following an iterative approach, together with feedback from people with multimorbidity and relevant stakeholders, we developed the MOBILIZE intervention.

RESULTS

The intervention included 24 (60 minutes) sessions of personalised exercise therapy and 24 (30 minutes) sessions of self-management support twice a week for 12 weeks, delivered in small groups by specifically trained physiotherapists. The intervention targets physiological, psychosocial, behavioural, and contextual factors to improve health-related quality of life and physical function in people living with multimorbidity.

CONCLUSIONS

We developed a personalised exercise therapy and self-management support programme for people with multimorbidity. The intervention will be tested for its safety and effectiveness in a randomised controlled trial.

The effect of a methadone reformulation on opioid agonist treatment outcomes: A population-based study in British Columbia, Canada, 2013-14

INTRODUCTION

The province of British Columbia, Canada, changed the existing oral anhydrous methadone solution to a 10-times more concentrated pre-mixed solution, Methadose®, on February 1, 2014. We aimed to assess the immediate effects of the methadone reformulation on missed doses, days off methadone, changes in medication dosing and dispensations of opioids for pain, and hospitalizations and mortality among all people receiving treatment at or near the time of the change.

METHODS

We conducted a population-based retrospective cohort study including all individuals receiving at least one methadone dispensation in the 12 months prior to the study period. We executed a difference-in-differences analysis by estimating a multivariate regression model to compare outcomes in the three months before and after the reformulation (November 1, 2013 to April 30, 2014) versus a time-lagged control cohort with similar characteristics observed during an equivalent nonoverlapping interval. We used daily individual-level linked health administrative data capturing missed doses, days off methadone, changes in methadone dosing, concurrent dispensations of opioids for pain, hospitalizations, and mortality. We stratified the cohorts into three subgroups: (i) those receiving OAT for ≥12 months; (ii) those receiving OAT for <12 months; and (iii) those not receiving OAT at the start of the study period. We conducted sensitivity analyses and placebo tests to assess the robustness of our results.

RESULTS

Among the 16,339 individuals receiving methadone during the study period, the reformulation was associated with more instances of methadone dose increases (34.5% [95% Confidence Interval (CI): 27.4%, 41.5%]). For those retained in treatment ≥12 months prior to the study period (n = 7449), the reformulation was associated with more instances of methadone dose increases (50.2% [39.5%, 60.8%]) and dispensations of opioids for pain (62.2% [40.8%, 83.5%]), as well as an increase in missed doses (41.9% [29.1%, 54.7%]) and days off methadone (62.6% [39.7%, 85.4%]). We found no statistically significant change in risk of hospitalization or mortality. Sensitivity analyses supported our results.

CONCLUSION

Our results reinforce the need expressed by people receiving methadone for greater client involvement in the planning and implementation of regulatory changes that may impact client care, especially those patients with a relatively long treatment history.

Observing treatment outcomes in other patients can elicit augmented placebo effects on pain treatment: a double-blinded randomized clinical trial with patients with chronic low back pain

ABSTRACT

Clinical research on social observational learning (SoL) as an underlying mechanism for inducing expectancy and eliciting analgesic placebo effects is lacking. This double-blinded randomized controlled clinical trial investigated the influence of SoL on medication-augmenting placebo effects in 44 patients with chronic low back pain. Our hypothesis was that observing positive drug effects on pain and mobility in another patient could increase pain reduction and functional capacity. To test this, we compared the effects of observing positive treatment outcomes in a sham patient (the social learning group [SoLG]) vs hearing the same sham patient report neutral effects (the control group). In the SoLG, the sham patient told peers about pain reduction due to amitriptyline and demonstrated his improved mobility by bending forwards and sideways while he told the control group only that he was taking amitriptyline. The primary outcome was a reduction in clinical low back pain self-ratings. The secondary outcome was perceptions of pain-related disability. The exploratory outcome was mood and coping statements. Data collection occurred before and after the intervention and 2 weeks later. After the intervention, pain decreased in both groups (F [1, 41] = 7.16, P < 0.05, d = 0.83), with no difference between groups. However, the SoLG showed a significantly larger decrease in perceived disability (F [1, 41] = 5, P < 0.05, d = 0.63). The direct observation of patient with chronic low back pain of positive treatment outcomes in the sham patient seems to have enhanced the treatment effects while indirect verbal reports of reduced pain did not.

[Neurobiological and neurochemical mechanisms of placebo analgesia]

BACKGROUND

The efficacy of pain therapies can be substantially modulated by treatment expectations, which is reflected by the substantial placebo effects observed in pain (so called placebo analgesia).

QUESTION

What is currently known about the neurobiological and neurochemical mechanisms underlying placebo analgesia?

MATERIALS AND METHODS

A focused presentation of key publications in the field embedded in a structured overview of the mechanistic concepts and current theories according to recent evidence.

RESULTS

Experimental studies with functional neuroimaging showed that the effect of placebo analgesia is reflected by changes in brain activity related to pain processing and cognitive control. The important neurotransmitters involved include opioids and dopamine.

CONCLUSION

Placebo analgesia is associated with complex neurobiological and -physiological mechanisms. An advanced comprehension of these processes should be applied to optimize existing and future therapeutic approaches in pain therapy.

Erwartungsfokussierte psychotherapeutische Interventionen bei Depression: ein Behandlungsmanual

Hintergrund

Kognitive Verhaltenstherapie (KVT) ist bei Depression langfristig wirksam, jedoch besteht Verbesserungsbedarf. In der Forschung zum Placeboeffekt und der Neurowissenschaft wird die zentrale Bedeutung von Erwartungen immer deutlicher. Neue Therapieansätze zur Modifikation dysfunktionaler Erwartungen (erwartungsfokussierte psychotherapeutische Interventionen, EFPI) scheinen ein vielversprechender Baustein zur Verbesserung der klassischen KVT zu sein.

Ziel der Arbeit

Die wesentlichen Bausteine eines EFPI-Behandlungsmanuals bei Depression werden vorgestellt.

Material und Methoden

Das Manual ist auf 24 Sitzungen (Kurzzeittherapie) ausgelegt. Es umfasst 5 Sitzungen Psychoedukation zu Erwartungsformulierung, -überprüfung und -verletzung sowie zur kognitiven Immunisierung (nachträgliche Umbewertung erwartungsverletzender Erfahrungen). Nach der Psychoedukation folgt eine Phase, in der in jeder Sitzung ein Verhaltensexperiment durchgeführt oder geplant wird. Die Verhaltensexperimente sollen zentrale krankheitsaufrechterhaltende Erwartungen herausfordern („Erwartungsverletzung“). Zusätzlich werden kognitive Immunisierungsstrategien besprochen und nach Möglichkeit verhindert. In der letzten Sitzung erfolgen eine Zusammenfassung und Konsolidierung des Erarbeiteten im Sinne einer Rückfallprophylaxe. Das Manual wurde in einer kleinen Pilotstudie (n = 5) erprobt.

Ergebnisse

Die EFPI-Therapie wurde von allen Beteiligten gut angenommen. Eine umfassende Evaluation erfolgt derzeit.

Diskussion

Das EFPI-Manual stellt die Fokussierung einer KVT auf möglichst viele, deutliche Erwartungsüberprüfungen bei zusätzlicher Adressierung kognitiver Immunisierung dar. Gezielt können persistierende, dysfunktionale Erwartungen von Personen mit Depression behandelt werden.

Impact of the COVID-19 pandemic on patients with chronic pain in Germany: associations with expectations and control beliefs

Background

While the COVID‐19 pandemic is affecting people's well‐being worldwide, it may place a particularly high burden on people with chronic pain, as pain is known to be influenced by societal and psychological conditions.

Methods

In this observational study, we conducted telephone interviews with 196 patients with chronic pain to assess the impact of the pandemic on various aspects of their pain and everyday life. The initial interviews were conducted between April and May 2020 and were followed up by a second interview between August and December 2020.

Results

A substantial percentage of patients (39% at the first and 32% at the second interview) reported an increase in pain intensity due to the pandemic. Exploratory analyses revealed that patients who already suffered from greater pain and who experienced greater restrictions due to the pandemic were more likely to express pain worsening. Psychological factors such as negative expectations about the development of their pain and pain treatment and a high external locus of control were also associated with increases in pain.

Conclusions

These findings illustrate the complexity of chronic pain, suggesting that not only the impact of the pandemic on various areas of life but also the severity of the pain‐symptoms themselves and psychological factors influence the course of patients' symptoms during the pandemic.

Significance

This study underlines the importance of psychosocial factors in chronic pain and demonstrates that the societal and psychological impact of the COVID‐19 pandemic can affect patients' pain and their ability to cope with it. The extent to which patients experience pain aggravation seems to interact with other psychological factors such as pain expectations and control beliefs.

[Seeing others is believing-analgesic placebo effects through observational learning?]

Hintergrund

Es gibt viele Studien zur Placeboanalgesie und deren zugrundliegenden Wirkmechanismen, die eine Behandlung von Patient:innen mit chronischen Schmerzen signifikant verbessern können. Beobachtungslernen als ein Wirkmechanismus wurde hingegen noch wenig untersucht.

Fragestellung

Das Ziel der Arbeit ist es, einen Überblick über die aktuelle Forschungslage zu Placeboanalgesie durch Beobachtungslernen zu geben. Dabei soll geklärt werden, ob Beobachtungslernen überhaupt einen signifikanten Placeboeffekt auslösen kann und durch welche Faktoren dieses Lernen beeinflusst wird.

Material und Methoden

Dafür wurden die Forschungsdatenbanken nach Studien zur Placeboanalgesie durch Beobachtungslernen durchsucht.

Ergebnisse

Nach der Anwendung der Ein- und Ausschlusskriterien verblieben 12 Studien. Es gab nur eine Studie, die an Patient:innen mit chronischen Schmerzen durchgeführt wurde. Die geringe Anzahl an Studien lässt noch keine allgemeingültigen Aussagen zu, aber es gibt erste Hinweise für die folgenden Aussagen: Beobachtungslernen von Placeboeffekten ist unter Laborbedingungen möglich und eine Aufmerksamkeitslenkung ist wichtig. Die Effektstärken reichen von klein bis groß. Die Effekte von klassischer Konditionierung und Beobachtungslernen sind vergleichbar. Live-Modelle, Videoaufnahmen und Bilder lösen ähnliche Effekte aus. Beobachtungslernen führt zu einer Erwartungsänderung.

Diskussion

Die vorliegende Evidenz liefert die Grundlage dafür, dass theoretisch und auch praktisch klinisch signifikante Effekte möglich sind. Weitere Studien sind nötig, um diese Aussagen verlässlich auch auf chronische Schmerzpatient:innen zu beziehen.

Analgetische Placeboeffekte und Implikationen für die Behandlung chronischer Schmerzen

Die Behandlung von chronischen Schmerzen kann langwierig sein. Erste Ansätze zur Nutzung von Placeboeffekten bei der Behandlung von chronischen Schmerzen zeigen erfolgversprechende Ergebnisse und können dazu beitragen, die z. T. frustranen Therapieoptionen zu verbessern. Daher sollten Placeboeffekte zur verbesserten Behandlung genutzt werden. Im derzeitigen Modell zur Entstehung von Placeboeffekten spielt die Erwartung eine zentrale Rolle. Eine positive oder negative Erwartung wird durch psychologische und biologische „State“- und „Trait“-Faktoren der Patient:innen sowie die früheren Lernerfahrungen, die der:die Patient:in mitbringt, beeinflusst. Aus diesem Modell ergeben sich Implikationen für die klinische Praxis: Positive Erwartungen sollten unterstützt werden, wobei unrealistische Erwartungen wiederum den Placeboeffekt reduzieren. Negative Erwartungen sollten kritisch diskutiert werden. Es sollte im interdisziplinären Team eine gemeinsame Botschaft an die Patient:innen vermittelt werden. Open-Label-Placebos können als Intervention genutzt werden, um die Selbstwirksamkeit zu steigern.

Music-Induced Analgesia in Healthy Participants Is Associated With Expected Pain Levels but Not Opioid or Dopamine-Dependent Mechanisms

Music interventions accommodate the profound need for non-pharmacological pain treatment. The analgesic effect of listening to music has been widely demonstrated across studies. Yet, the specific mechanisms of action have still to be elucidated. Although the endogenous opioid and dopamine systems have been suggested to play an important role, a direct link has not been established. In addition, the involvement of placebo mechanisms is likely while largely unexplored. We examined the analgesic effect of music in healthy participants (n = 48) using a 3 × 3 within-subjects design with pharmacological manipulations and a matched, auditory control for music. Participants were exposed to thermal pain stimuli while listening to three auditory excerpts: music (active condition), nature sound (matched, auditory contextual condition), and noise (neutral control condition). The participants rated their expected and perceived pain levels in relation to each of the auditory excerpts. To investigate the involvement of the endogenous opioid and dopamine systems, the test session was performed three times on separate days featuring a double-blind randomized oral administration of naltrexone (opioid antagonist), haloperidol (dopamine antagonist), and an inactive agent (control). Our results support an analgesic effect of music. Contrary to current hypotheses, neither of the antagonists attenuated the effect of music. Yet, the participants' expectations for pain relief predicted their perceived pain levels during the auditory excerpts—even when controlling for a gradual learning effect. In conclusion, we demonstrate that the analgesic effect of music is at least partially mediated by expectations of an analgesic effect—a core mechanism in placebo effects—but not by opioid and dopamine-dependent mechanisms.