Components of placebo effect: randomised controlled trial in patients with irritable bowel syndrome

Lack of Effects of the Presence of a Dog on Pain Perception in Healthy Participants-A Randomized Controlled Trial

Animal-assisted interventions (AAIs) have been shown to be effective in the treatment of pain. Studies suggest that relationships with animals can have comparable qualities to relationships with humans and that this enables animals to provide social support. Further, the presence of an animal can strengthen the therapeutic alliance between patients and treatment providers. This suggests that the analgesic effects of AAI might be mediated by social support from an animal or by strengthening the alliance between the patient and the treatment provider. To test these assumptions, we examined the effects of the presence of a dog on experimentally induced pain in a pain assessment and a pain therapy context. Hundred thirty-two healthy participants were randomly assigned to the conditions “pain,” “pain + dog,” “pain + placebo,” or “pain + placebo + dog.” We collected baseline and posttreatment measurements of heat-pain tolerance and the heat-pain threshold and of the corresponding subjective ratings of heat-pain intensity and unpleasantness as well as of participants' perceptions of the study investigator. The primary outcome was heat-pain tolerance. The presence of the dog did not influence the primary outcome (“pain” vs. “pain + dog”: difference = 0.04, CI = −0.66 to 0.74, p = 0.905; “pain + placebo” vs. “pain + placebo + dog”: difference = 0.43, CI = −0.02 to 0.88, p = 0.059). Participants did also not perceive the study investigator to be more trustworthy in the presence of the dog (“pain” vs. “pain + dog”: difference = 0.10, CI = −0.67 to 0.87, p = 0.796; “pain + placebo” vs. “pain + placebo + dog”: difference = 0.11, CI = −0.43 to 0.64, p = 0.695). The results indicate that the mere presence of a dog does not contribute to pain reduction and that the analgesic effects of AAI that previous studies have found is not replicated in our study as AAI did not increase perceived social support and had no effect on the alliance between the participant and the treatment provider. We assume that the animal most likely needs to be an integrated and plausible part of the treatment rationale so that participants are able to form a treatment-response expectation toward AAI.

Clinical Trial Registration: This study was preregistered as a clinical trial on www.clinicaltrials.gov (Identifier: NCT0389814).

Placebo effects and neuromodulation for depression: a meta-analysis and evaluation of shared mechanisms

There is growing evidence that placebo effects can meaningfully modulate the brain. However, there has been little consideration of whether these changes may overlap with regions/circuits targeted by depression treatments and what the implications of this overlap would be on measuring efficacy in placebo-controlled clinical trials. In this systematic review and meta-analysis, we searched PubMed/Medline and Google Scholar for functional MRI and PET neuroimaging studies of placebo effects. Studies recruiting both healthy subjects and patient populations were included. Neuroimaging coordinates were extracted and included for Activation Likelihood Estimation (ALE) meta-analysis. We then searched for interventional studies of transcranial magnetic stimulation (TMS) and deep brain stimulation (DBS) for depression and extracted target coordinates for comparative spatial analysis with the placebo effects maps. Of 1169 articles identified, 34 neuroimaging studies of placebo effects were included. There were three significant clusters of activation: left dorsolateral prefrontal cortex (DLPFC) (x = -41, y = 16, z = 34), left sub-genual anterior cingulate cortex (sgACC)/ventral striatum (x = -8, y = 18, z = -15) and the right rostral anterior cingulate cortex (rACC) (x = 4, y = 42, z = 10). There were two significant deactivation clusters: right basal ganglia (x = 20, y = 2, z = 7) and right dorsal anterior cingulate cortex (dACC) (x = 1, y = -5, z = 45). TMS and DBS targets for depression treatment overlapped with the left DLPFC cluster and sgACC cluster, respectively. Our findings identify a common set of brain regions implicated in placebo effects across healthy individuals and patient populations, and provide evidence that these regions overlap with depression treatment targets. We model the statistical impacts of this overlap and demonstrate critical implications on measurements of clinical trial efficacy for this field.

Patients' perceptions on non-specific effects of acupuncture: Qualitative comparison between responders and non-responders

BACKGROUND

Non-specific effect of acupuncture constitutes part of the overall effect generated via clinical encounter beyond needle insertion and stimulation. It is unclear how responders and non-responders of acupuncture experience non-specific effects differently. We aimed to compare their experiences in a nested qualitative study embedded in an acupuncture randomized trial on functional dyspepsia.

METHODS

Purposive sampling was used to capture experience of responders (n=15) and non-responders (n=15) to acupuncture via individual in-depth interviews. Design and analysis followed a framework analysis approach, with reference to an existing model on acupuncture non-specific effects. Themes emerging outside of this model were purposefully explored.

RESULTS

Responders had a more trusting relationship with acupuncturist in response to their expression of empathy. In turn they were more actively engaged in lifestyle modifications and dietary advice offered by acupuncturists. Non-responders were not satisfied with the level of reassurance regarding acupuncture safety. They were also expecting more peer support from fellow participants, regarded that as an empowerment process for initiating and sustaining lifestyle changes.

CONCLUSIONS

Our results highlighted key differences in acupuncture non-specific effect components experienced by responders and non-responders. Positive non-specific effects contributing to overall benefits could be enhanced by emphasizing on empathy expression from acupuncturists, trust-building, offering appropriate explanations on safety, and organizing patient support groups. Further research on the relative importance of each component is warranted.

Long-term effect of moxibustion on irritable bowel syndrome with diarrhea: a randomized clinical trial

BACKGROUND

Moxibustion is increasingly used for treatment of irritable bowel syndrome (IBS). This study investigated the long-term effects of moxibustion for IBS with diarrhea (IBS-D).

METHODS

Patients with IBS-D were assigned to receive moxibustion or sham moxibustion (52 each, 3× per week, 6 weeks) and were followed up to 24 weeks. The acupoints were bilateral ST25 and ST36, body surface temperatures at acupoints were 43°C ± 1°C and 37°C ± 1°C for the moxibustion and sham groups, respectively. Primary outcome was changes in IBS Adequate Relief (IBS-AR) from baseline to 6 weeks. Secondary outcomes included the following: IBS symptom severity scale (IBS-SSS), Bristol stool form scale (BSS), IBS quality of life (IBS-QOL), and Hospital Anxiety and Depression Scale (HADS).

RESULTS

Based on an intention-to-treat analysis, the rate of IBS-AR in the moxibustion group was significantly higher than the sham group at 6 weeks (76.9% versus 42.3%; p < 0.001); the mean decrease of total IBS-BSS score in the moxibustion group was lower than that of the sham group (-116.9 versus -61.5; p < 0.001), both of which maintained throughout the follow-up period. Five specific domains of the IBS-SSS were lower in the moxibustion group than the sham, throughout (p < 0.001). At week 6, the rate of reduction >50 points in IBS-SSS of the treatment group was significantly higher than that of the sham (p < 0.001), which persisted throughout the follow-up period. Similar long-lasting improvements were observed in BSS, stool frequency, and stool urgency (p < 0.001). Improvements of IBS-QOL and HADS were comparable between the groups.

CONCLUSIONS

Moxibustion treatment benefits the long-term relief of symptoms in IBS-D patients.

TRIAL REGISTRATION

Clinical trials.gov (NCT02421627). Registered on 20 April 2015.

Systematic Review and Meta-Analysis: Clinical, Endoscopic, Histological and Safety Placebo Rates in Induction and Maintenance Trials of Ulcerative Colitis

BACKGROUND AND AIMS

Quantifying placebo rates and the factors influencing them are essential to inform trial design. We provide a contemporary summary of clinical, endoscopic, histological and safety placebo rates in induction and maintenance clinical trials of ulcerative colitis, and identify factors influencing them.

METHODS

MEDLINE, EMBASE and the Cochrane library were searched from April 2014 to April 2020, updating a prior meta-analysis that searched from inception to April 2014. We included placebo-controlled trials of aminosalicylates, corticosteroids, immunosuppressives, small-molecules and biologics in adults with ulcerative colitis. Placebo rates were pooled using random-effects and mixed-effects meta-regression models to assess the associated study-level.

RESULTS

In 119 trials [92 induction, 27 maintenance] clinical, endoscopic and histological remission placebo rates for induction trials were 11% (95% confidence interval [CI] 9-13%), 19% [95% CI 15-23%] and 15% [95% CI 11-19%], respectively; for maintenance trials, clinical and endoscopic placebo remission rates were 18% [95% CI 12-25%] and 20% [95% CI 15-25%], respectively. Higher endoscopic subscore and a higher rate of exposure to prior biologic therapy at enrolment were associated with lower clinical and endoscopic placebo remission rates. Absence of central reading was associated with an increase in placebo endoscopic response and remission rates. More follow-up visits and increasing trial duration were associated with higher clinical placebo rates.

CONCLUSIONS

Placebo rates in ulcerative colitis trials vary according to the endpoint assessed, whether it is for assessment of response or remission, and whether the trial is designed for induction or maintenance. These contemporary rates across different endpoints and drug classes will help to inform trial design.

The neurologic pain signature responds to nonsteroidal anti-inflammatory treatment vs placebo in knee osteoarthritis

Supplemental Digital Content is Available in the Text.

fMRI-based measures, validated for nociceptive pain, respond to acute osteoarthritis pain, are not sensitive to placebo, and are mild-to-moderately sensitive to naproxen.

Introduction:

Many drug trials for chronic pain fail because of high placebo response rates in primary endpoints. Neurophysiological measures can help identify pain-linked pathophysiology and treatment mechanisms. They can also help guide early stop/go decisions, particularly if they respond to verum treatment but not placebo. The neurologic pain signature (NPS), an fMRI-based measure that tracks evoked pain in 40 published samples and is insensitive to placebo in healthy adults, provides a potentially useful neurophysiological measure linked to nociceptive pain.

Objectives:

This study aims to validate the NPS in knee osteoarthritis (OA) patients and test the effects of naproxen on this signature.

Methods:

In 2 studies (50 patients, 64.6 years, 75% females), we (1) test the NPS and other control signatures related to negative emotion in knee OA pain patients; (2) test the effect of placebo treatments; and (3) test the effect of naproxen, a routinely prescribed nonsteroidal anti-inflammatory drug in OA.

Results:

The NPS was activated during knee pain in OA (d = 1.51, P < 0.001) and did not respond to placebo (d = 0.12, P = 0.23). A single dose of naproxen reduced NPS responses (vs placebo, NPS d = 0.34, P = 0.03 and pronociceptive NPS component d = 0.38, P = 0.02). Naproxen effects were specific for the NPS and did not appear in other control signatures.

Conclusion:

This study provides preliminary evidence that fMRI-based measures, validated for nociceptive pain, respond to acute OA pain, do not appear sensitive to placebo, and are mild-to-moderately sensitive to naproxen.

Open-Label Placebo Treatment for Experimental Pain: A Randomized-Controlled Trial with Placebo Acupuncture and Placebo Pills

Objective: An open-label placebo (OLP) is a placebo treatment in which the patient is aware that the treatment is a placebo. OLPs are considered effective for reducing pain, and previous studies have shown a stronger placebo effect for placebo acupuncture than for placebo pills. In this study, the authors compared the analgesic effects of OLP pills, OLP acupuncture, and a no treatment condition in healthy participants, and then examined the factors contributing to the OLP effect. Design: Randomized controlled crossover trial. Settings/Location: College of Korean Medicine, Kyung Hee University, Seoul, Republic of Korea. Subjects: 34 healthy participants. Intervention: Participants received three different treatments ("OLP-pill," "OLP-acupuncture," and "no treatment") on three separate days in random order. Outcome Measurements: Before and after the treatment, heat pain stimuli were applied to the participants' hands, and pain tolerance, intensity, and unpleasantness were measured using a visual analog scale (range, 0-10). Results: Data of 31 participants were included in the analysis. The authors found significant analgesic effects of the placebo pill and placebo acupuncture in the OLP condition. Regression analyses revealed that expectations regarding treatment and practitioner identity influenced the analgesic effects of OLP acupuncture. There was no adverse event. Conclusions: Expectations regarding treatment and practitioner identity influenced the analgesic effect of placebo acupuncture without deception. These findings provide new information regarding the cognitive factors underlying pharmacologic and nonpharmacologic treatments. Clinical Trial Registration Number: KCT0004928.

Clinical effects of glabellar botulinum toxin injections on borderline personality disorder: A randomized controlled trial

BACKGROUND

Inhibition of frowning via injections of botulinum toxin A (BTX) into the glabellar region has shown beneficial effects in the treatment of major depression. Preliminary research suggests that improvements in the affective domain are not depression-specific, but may also translate to other psychiatric disorders.

AIM

This 16-week, single-blind, two-center randomized controlled trial investigated the influence of BTX on clinical symptoms of borderline personality disorder (BPD).

METHODS

Fifty-four patients with BPD were randomly assigned to treatment with BTX (n = 27) or a minimal acupuncture (ACU) control condition (n = 27). Clinical outcomes were followed at 2, 4, 6, 8, 12, and 16 weeks. Primary endpoint was the relative score change on the Zanarini Rating Scale for Borderline Personality Disorder (ZAN-BPD) 8 weeks after baseline relative to the control group and adjusted for treatment center. Secondary and additional outcome variables were self-rated borderline symptoms, comorbid symptoms of depression, psychological distress, and clinical global impression.

RESULTS

Participants showed significant improvements at the primary efficacy endpoint in both treatment groups (BTX: M = -0.39, SD = 0.39; ACU: M = -0.35, SD = 0.42), but no superior effect of the BTX condition in comparison with the control intervention was found-F(1,5323) = 0.017, p = 0.68). None of the secondary or additional outcomes yielded significant group differences. Side effects were mild and included headache, transient skin or muscle irritations, and dizziness.

CONCLUSION

Evidence regarding the efficacy of BTX for BDP remains limited, and the design of adequate control conditions presents an opportunity for further research.ClinicalTrials.gov registry: Botulinum Toxin A for Emotional Stabilization in Borderline Personality Disorder (BPD), NCT02728778, https://clinicaltrials.gov/ct2/show/NCT02728778.

The Strength of Alliance in Individual Psychotherapy and Patient's Wellbeing: The Relationships of the Therapeutic Alliance to Psychological Wellbeing, Satisfaction With Life, and Flourishing in Adult Patients Attending Individual Psychotherapy

OBJECTIVES

The central aim of the research was to verify and determine the strength of the relationships of therapeutic alliance to wellbeing, life satisfaction, and flourishing in patients attending individual psychotherapy. The relationships were assessed based on different sources of information about the quality of the working alliance: patient's evaluation and patient's and psychotherapist's joint evaluations.

DESIGN

The author applied Bordin's pantheoretical model of alliance and two different conceptions of wellbeing, operationalized as hedonistic and eudaimonic.

METHODS

The 411 participants included 252 patients and 159 psychotherapists. To test the hypotheses, 16 joint and separate models of structural relations were built and analyzed empirically using SEM. Correlations were analyzed between alliance factors and those of wellbeing, satisfaction, and flourishing.

RESULTS

The actual impact of working alliance quality on psychological wellbeing proved to be stronger compared to the relations between alliance and satisfaction or flourishing. The results of analyses revealed low, though usually positive and significant, correlations between the dimensions of alliance and those of wellbeing, life satisfaction, and flourishing.

CONCLUSIONS

The empirical data and the strategy of analyses brought the expected results, confirming that patient's and psychotherapist's perception of a strong therapeutic alliance is crucial for the optimization of patient's functioning and wellbeing. It turns out that the therapeutic alliance is, above all, a factor of wellbeing understood more deeply than merely as current pleasure. The study also showed that no factor isolated from other components of alliance increased the quality of patient's mental functioning more than others.

Intra-articular placebo effect in the treatment of knee osteoarthritis: a survey of the current clinical evidence

Knee osteoarthritis (KOA) is a debilitating disease characterized by chronic pain, stiffness, and decreased mobility. Intra-articular injectable therapies show good clinical efficacy in improving symptoms; however, these therapies and their comparators (intra-articular saline) have been associated with a large underlying placebo effect. We aimed to describe the existing evidence on the challenges, hypotheses, and potential solutions to mitigate the intra-articular placebo effect in clinical trials in KOA. A targeted literature review was conducted by searching Embase, MEDLINE®, and CENTRAL using predefined study selection criteria. All eligible studies identified were extracted for relevant data, and results were narratively summarized. Forty-three studies were included following screening. Challenges associated with the intra-articular placebo effect included its ability to mask the comparative efficacy of active treatments in trials (n = 7 studies), long-lasting effects (up to 6 months; n = 3), and substantial variation of placebo effect sizes across populations (n = 3). Hypotheses for the mechanism of the placebo effect included aspiration of synovial fluid during administration (n = 6) and dilution of inflammatory mediators (n = 2). Factors affecting the placebo effect size were more invasive routes of administration (e.g., injection versus oral; n = 4) and patient expectations (n = 2). Proposed solutions included the suggestion for readers to weigh the relevance of clinical trial evidence against the presence of large underlying placebo effects (n = 9), discontinuation of intra-articular saline as an appropriate placebo (n = 5), and inclusion of 'no treatment' or sham injection as a control (n = 4). The intra-articular placebo effect is a well-documented occurrence in KOA clinical trials, and it is suggested that it be accounted for when designing randomized controlled trials. Awareness and understanding of the intra-articular placebo effect in KOA are required for fair interpretation of clinical trial evidence.

Clinician Perspectives of Communication with Aboriginal and Torres Strait Islanders Managing Pain: Needs and Preferences

Poor communication is an important factor contributing to health disparity. This study sought to investigate clinicians’ perspectives about communicating with Aboriginal and Torres Strait Islander patients with pain. This multi-site and mixed-methods study involved clinicians from three pain management services in Queensland, Australia. Clinicians completed a survey and participated in focus groups. Clinicians rated the importance of communication training, their knowledge, ability, and confidence in communicating with Aboriginal and Torres Strait Islander patients using a 5-point Likert scale. Rating scores were combined into low (scores 1–2); moderate (score 3) and high (scores 4–5). Informed by an interpretive description methodology, thematic analysis of focus group data was used to identify the communication needs and training preferences of clinicians. Overall (N = 64), 88% of clinicians rated the importance of communication training when supporting Aboriginal and Torres Strait Islander patients as “high”. In contrast, far fewer clinicians rated as “high” their knowledge (28%), ability (25%) and confidence (28%) in effectively communicating with Aboriginal and Torres Strait Islander patients. Thematic analysis identified three areas of need: knowledge of Aboriginal and Torres Strait Islander cultures, health beliefs, and understanding cross-cultural cues. Communication skills can be learned and training, in the form of a tailored intervention to support quality engagement with Aboriginal and Torres Strait Islander patients, should combine cultural and communication aspects with biomedical knowledge.

Patient-clinician brain concordance underlies causal dynamics in nonverbal communication and negative affective expressivity

Patient-clinician concordance in behavior and brain activity has been proposed as a potential key mediator of mutual empathy and clinical rapport in the therapeutic encounter. However, the specific elements of patient-clinician communication that may support brain-to-brain concordance and therapeutic alliance are unknown. Here, we investigated how pain-related, directional facial communication between patients and clinicians is associated with brain-to-brain concordance. Patient-clinician dyads interacted in a pain-treatment context, during synchronous assessment of brain activity (fMRI hyperscanning) and online video transfer, enabling face-to-face social interaction. In-scanner videos were used for automated individual facial action unit (AU) time-series extraction. First, an interpretable machine-learning classifier of patients' facial expressions, from an independent fMRI experiment, significantly distinguished moderately painful leg pressure from innocuous pressure stimuli. Next, we estimated neural-network causality of patient-to-clinician directional information flow of facial expressions during clinician-initiated treatment of patients' evoked pain. We identified a leader-follower relationship in which patients predominantly led the facial communication while clinicians responded to patients' expressions. Finally, analyses of dynamic brain-to-brain concordance showed that patients' mid/posterior insular concordance with the clinicians' anterior insula cortex, a region identified in previously published data from this study¹, was associated with therapeutic alliance, and self-reported and objective (patient-to-clinician-directed causal influence) markers of negative-affect expressivity. These results suggest a role of patient-clinician concordance of the insula, a social-mirroring and salience-processing brain node, in mediating directional dynamics of pain-directed facial communication during therapeutic encounters.

What Do Placebo and Nocebo Effects Have to Do With Health Equity? The Hidden Toll of Nocebo Effects on Racial and Ethnic Minority Patients in Clinical Care

A placebo effect is a positive clinical response to non-specific elements of treatment with a sham or inert replica of a drug, device, or surgical intervention. There is considerable evidence that placebo effects are driven by expectation of benefit from the intervention. Expectation is shaped by a patient's past experience, observations of the experience of others, and written, verbal, or non-verbal information communicated during treatment. Not surprisingly, expectation in the clinical setting is strongly influenced by the attitude, affect, and communication style of the healthcare provider. While positive expectations can produce beneficial effects, negative information and experiences can lead to negative expectations, and consequently negative or nocebo effects. Key components identified and studied in the placebo and nocebo literature intersect with factors identified as barriers to quality care in the clinical setting for Black patients and other patients of color, including poor patient-clinician communication, medical mistrust, and perceived discrimination. Thus, in the context of discrimination and bias, the absence of placebo and presence of nocebo-generating influences in clinical settings could potentially reinforce racial and ethnic inequities in clinical outcomes and care. Healthcare inequities have consequences that ripple through the medical system, strengthening adverse short- and long-term outcomes. Here, we examine the potential for the presence of nocebo effects and absence of placebo effects to play a role in contributing to negative outcomes related to unequal treatment in the clinical encounter.

Placebo and nocebo responses in randomised, controlled trials of medications for ADHD: a systematic review and meta-analysis

The nature and magnitude of placebo and nocebo responses to ADHD medications and the extent to which response to active medications and placebo are inter-correlated is unclear. To assess the magnitude of placebo and nocebo responses to ADHD and their association with active treatment response. We searched literature until June 26, 2019, for published/unpublished double-blind, randomised placebo-controlled trials (RCTs) of ADHD medication. Authors were contacted for additional data. We assessed placebo effects on efficacy and nocebo effects on tolerability using random effects meta-analysis. We assessed the association of study design and patient features with placebo/nocebo response. We analysed 128 RCTs (10,578 children/adolescents and 9175 adults) and found significant and heterogenous placebo effects for all efficacy outcomes, with no publication bias. The placebo effect was greatest for clinician compared with other raters. We found nocebo effects on tolerability outcomes. Efficacy outcomes from most raters showed significant positive correlations between the baseline to endpoint placebo effects and the baseline to endpoint drug effects. Placebo and nocebo effects did not differ among drugs. Baseline severity and type of rating scale influenced the findings. Shared non-specific factors influence response to both placebo and active medication. Although ADHD medications are superior to placebo, and placebo treatment in clinical practice is not feasible, clinicians should attempt to incorporate factors associated with placebo effects into clinical care. Future studies should explore how such effects influence response to medication treatment. Upon publication, data will be available in Mendeley Data: PROSPERO (CRD42019130292).

Positive Treatment Expectations Shape Perceived Medication Efficacy in a Translational Placebo Paradigm for the Gut-Brain Axis

Placebo research has established the pivotal role of treatment expectations in shaping symptom experience and patient-reported treatment outcomes. Perceived treatment efficacy constitutes a relevant yet understudied aspect, especially in the context of the gut-brain axis with visceral pain as key symptom. Using a clinically relevant experimental model of visceral pain, we elucidated effects of pre-treatment expectations on post-treatment perceived treatment efficacy as an indicator of treatment satisfaction in a translational placebo intervention. We implemented positive suggestions regarding intravenous treatment with a spasmolytic drug (in reality saline), herein applied in combination with two series of individually calibrated rectal distensions in healthy volunteers. The first series used distension pressures inducing pain (pain phase). In the second series, pressures were surreptitiously reduced, modeling pain relief (pain relief phase). Using visual analog scales (VAS), expected and perceived treatment efficacy were assessed, along with perceived pain intensity. Manipulation checks supported that the induction of positive pre-treatment expectations and the modeling of pain relief were successful. Generalized Linear Models (GLM) were implemented to assess the role of inter-individual variability in positive pre-treatment expectations in perceived treatment efficacy and pain perception. GLM indicated no association between pre-treatment expectations and perceived treatment efficacy or perceived pain for the pain phase. For the relief phase, pre-treatment expectations (p = 0.024) as well as efficacy ratings assessed after the preceding pain phase (p < 0.001) were significantly associated with treatment efficacy assessed after the relief phase, together explaining 54% of the variance in perceived treatment efficacy. The association between pre-treatment expectations and perceived pain approached significance (p = 0.057) in the relief phase. Our data from an experimental translational placebo intervention in visceral pain support that reported post-treatment medication efficacy is shaped by pre-treatment expectations. The observation that individuals with higher positive expectations reported less pain and higher treatment satisfaction after pain relief may provide first evidence that perceived symptom improvement may facilitate treatment satisfaction. The immediate experience of symptoms within a given psychosocial treatment context may dynamically change perceptions about treatment, with implications for treatment satisfaction, compliance and adherence of patients with conditions of the gut-brain axis.

The placebo and nocebo effects in functional urology

A placebo is an inert substance normally used in clinical trials for comparison with an active substance. However, a placebo has been shown to have an effect on its own; commonly known as the placebo effect. A placebo is an essential component in the design of conclusive clinical trials but has itself become the focus of intense research. The placebo effect is partly the result of positive expectations of the recipient on the state of health. Conversely, a nocebo effect is when negative expectations from a substance lead to poor treatment outcomes and/or adverse events. Randomized controlled trials in functional urology have demonstrated the importance of the placebo and nocebo effects across different diseases such as overactive bladder, urinary incontinence, lower urinary tract symptoms and interstitial cystitis/painful bladder syndrome, as well as male and female sexual dysfunction. Understanding the true nature of the placebo-nocebo complex and the scope of its effect in functional urology could help urologists to maximize the positive effects of this phenomenon while minimizing its potentially negative effects.

Bibliometric Analysis of Functional Magnetic Resonance Imaging Studies on Acupuncture Analgesia Over the Past 20 Years

Background

Researches on the central mechanisms of acupuncture analgesia have been widely conducted worldwide. However, there is no bibliometric analysis of functional magnetic resonance imaging (fMRI) studies on acupuncture analgesia. This study visualized the current status, hot spots and frontiers of fMRI studies on acupuncture analgesia in the past 20 years to provide a theoretical basis for its clinical application.

Methods

All publications were obtained from Science Citation Index-Expanded (SCI-E) of Web of Science (WOS). We used CiteSpace to analyze publications, journals, cited journals, authors, cited authors, institutions, countries, references, and keywords. We also analyzed collaborative network maps and co-occurrence network maps.

Results

We retrieved a total of 797 articles. Regarding the volume of publications, the total number of annual publications showed a fluctuating but overall increasing trend. Evidence-based Complementary and Alternative Medicine (21 articles) was the most productive journal, and Pain (225 articles) was the most cited journal. The most productive author was Qin W (16 articles), and the most co-cited author was Hui KKS (111). The most prolific institution and country were Massachusetts General Hospital (34 articles) and USA (212 articles). “Pain” was the top-ranked for keyword frequency and centrality. “Functional connectivity” was the frontier hotspot for 2018–2021.

Conclusion

First, fMRI researches on acupuncture analgesia involved several countries (regions) and institutions, mainly located in the USA, China and Korea, and most of them were universities. In addition, the USA was a major contributor in this field. Second, in terms of disciplinary distribution, the literatures were mainly from clinical neurology, neuroscience, and radiology nuclear medicine medical imaging. Third, the keyword co-occurrence analysis showed that the hot keywords included pain, fMRI, and lower back pain. Fourth, through keyword clustering analysis, the hot disease was found to be lower back pain, and the hot contents were acupuncture specificity and frequency specificity. Fifth, a timeline analysis of the references identified that chronic low back pain and specificity will remain a hot topic for future research.

Psychological interventions for reducing anxiety in patients undergoing first-time colonoscopy: a pilot and feasibility study

OBJECTIVES

To assess the feasibility of a randomized controlled trial (RCT), evaluating the efficacy and patients' perceptions of a psychological intervention aimed at reducing anxiety levels in adults undergoing first-time colonoscopy.

METHODS

Adults undergoing first-time colonoscopy were randomized to a psychological intervention vs. sham intervention. The primary outcome was feasibility, defined as a recruitment rate of >50%. Patients' state anxiety was assessed before and after the intervention using the state-trait inventory for cognitive and somatic anxiety (STICSA) score. Follow-up interviews were performed within 1 week with a sample of patients and focus groups with clinical staff.

RESULTS

A total of 130 patients were recruited from 180 eligible patients (72%). Eighty were randomized and completed the study (n = 39) in the psychological intervention group and (n = 41) in the sham. In the psychological intervention group, pre- and postmedian STICSA scores were 29 and 24 (P < 0.001), respectively. In the sham group, pre- and postmedian scores were 31 and 25 (P < 0.001), respectively. Follow-up interviews with patients (n = 13) suggested that 100% of patients perceived the psychological intervention as beneficial and would recommend it to others.

CONCLUSION

The study was feasible. Patients in both groups improved their anxiety scores, but there were no significant differences between arms. Despite this, patients receiving psychological intervention perceived a benefit from the relaxation exercises.

Open-Label Placebo Treatment for Acute Postoperative Pain (OLP-POP Study): Study Protocol of a Randomized Controlled Trial

Introduction: Open-label placebos have been proposed as way of using long recognized analgesic placebo effects in an ethical manner. Recent evidence shows efficacy of open-label placebos for clinical conditions, but there is need for more research on open-label placebos in acute pain. In the treatment of acute postoperative pain, minimization of opioid related side effects remains one of the key challenges. Therefore, this study aims at investigating the potential of adding unconditioned open-label placebos to treatment as usual as a means of reducing opioid consumption and its related side effects in patients with acute postoperative pain. Methods and Analysis: This is the protocol of an ongoing single site randomized controlled trial. The first patient was enrolled in May 2020. In total, 70 patients suffering from acute postoperative pain following dorsal lumbar interbody fusion are randomized to either a treatment as usual group or an experimental intervention group. The treatment as usual group consists of participants receiving a patient-controlled morphine pump. On day 1 and 2 post-surgery, patients in the intervention group receive, in addition to treatment as usual, two open-label placebo injections per day along with an evidence-based treatment rationale explaining the mechanisms of placebos. The primary outcome is measured by means of self-administered morphine during day 1 and 2 post-surgery. Several other outcome measures including pain intensity and adverse events as well as potential predictors of placebo response are assessed. Analysis of covariance will be used to answer the primary research question and additional statistical techniques such as generalized linear mixed models will be applied to model the temporal course of morphine consumption. Discussion: This study will provide valuable insights into the efficacy of open-label placebos in acute pain and will potentially constitute an important step toward the implementation of open-label placebos in the clinical management of acute postoperative pain. In addition, it will shed light on a cost-efficient and patient-centered strategy to reduce opioid consumption and its related side effects, without any loss in pain management efficacy. Ethics and Dissemination: The "Ethikkommission Nordwest- und Zentralschweiz" (BASEC2020-00099) approved the study protocol. Results of the analysis will be submitted for publication in a peer-reviewed journal. Clinical Trial Registration: The study is registered at ClinicalTrials.gov (NCT04339023) and is listed in the Swiss national registry at kofam.ch (SNCTP000003720).

Reward anticipation buffers neuroendocrine and cardiovascular responses to acute psychosocial stress in healthy young adults

Research over the last 10 years suggests that the brain's reward system plays a crucial role in stress resilience. Notably, reward processing includes both an anticipatory (cue-triggered "wanting") phase and a consummatory ("liking") phase. However, previous studies manipulated rewards via direct reward administration, which makes it difficult to isolate the buffering effect of anticipating the reward stimulus. In the current study, we designed a paradigm to manipulate participants into generating reward anticipation or not and investigated whether reward anticipation can buffer psychological, neuroendocrine, and cardiovascular responses to psychosocial stress. A sample of 78 healthy young adults underwent the Trier Social Stress Test or placebo-Trier Social Stress Test after a reward anticipation task. Results showed that reward anticipation relieved subjective stress feelings, as well as the overall cortisol secretion and the increased heart rate induced by psychosocial stress. Taken together, these findings expanded our understanding of the role the reward system plays in stress resilience, and the possible psychological mechanism of the buffering effect for future stress study was also discussed.HIGHLIGHTSReward processing includes both an anticipatory and consummatory phasesThe buffering effect of anticipating the reward stimulus requires elucidationWe examined if said anticipation buffers varied responses to psychosocial stressReward anticipation relieved subjective stress, cortisol secretion, and heart rateWe clarified the role of the reward system in stress resilience.

Diagnoses of Exclusion in the Workup of Abdominal Complaints

Abdominal pain is a common complaint in the emergency department, comprising 8.8% of all visits. Despite advances in medicine and imaging, 20% to 30% of patients still leave the department without a definitive diagnosis, whichhis can be both distressing for patients and unsatisfying for providers. Diagnoses of exclusion can be perilous, and their application should be carefully considered in order to not overlook more emergent complaints. However, a working knowledge of diagnoses of exclusion can guide therapeutics and specialty referrals that can ultimately provide answers and relief to a patient population often at odds with available information and expectations.

Surgeons' behaviors and beliefs regarding placebo effects in surgery

Background and purpose - Emerging evidence from sham-controlled trials suggest that surgical treatment entails substantial non-specific treatment effects in addition to specific surgical effects. Yet, information on surgeons' actual behaviors and beliefs regarding non-specific treatment and placebo effects is scarce. We determined surgeons' clinical behaviors and attitudes regarding placebo effects.Methods - A national online survey was developed in collaboration with surgeons and administered via an electronic link.Results - All surgical clinics in Sweden were approached and 22% of surgeons participated (n = 105). Surgeons believed it was important for them to interact and build rapport with patients before surgery rather than perform surgery on colleagues' patients (90%). They endorsed the importance of non-specific treatment effects in surgery generally (90%) and reported that they actively harness non-specific treatment effects (97%), including conveying confidence and calm (87%), building a positive interaction (75%), and making eye contact (72%). In communication regarding the likely outcomes of surgery, surgeons emphasized accurate scientific information of benefits/risks (90%) and complete honesty (63%). A majority felt that the improvement after some currently performed surgical procedures might be entirely explained by placebo effects (78%). Surgeons saw benefits with sham-controlled surgery trials, nevertheless, they were reluctant to refer patients to sham controlled trials (46%).Interpretation - Surgeons believe that their words and behaviors are important components of their professional competence. Surgeons saw the patient-physician relationship, transparency, and honesty as critical. Understanding the non-specific components of surgery has the potential to improve the way surgical treatment is delivered and lead to better patient outcomes.

Patient expectations shape convalescence after major liver surgery - A prospective, randomized study

BACKGROUND

Several studies suggest an important influence of patient expectations on outcomes. We hypothesized that patient expectations with regard to length of postoperative stay influence convalescence after liver resections.

METHOD

This prospective, randomized study compared patients who were preoperatively either informed to be expected to stay 7-10 days (short arm) or 12-16 days (long arm) after major liver resections (≥4 segments). Additionally, psychological traits were assessed using questionnaires and the time to fulfillment of objective discharge criteria [oral analgesics only, first bowel movement, ability to tolerate solid food, full mobilization, no complications which need general anesthesia (>CD IIIa)] was defined as the primary endpoint.

RESULTS

Patients in the short arm reached the objective discharge criteria after 8.39 days (SD 3.60), while patients in the long arm needed 12.73 days (SD 3.43) (p = 0.001). The actual length of stay in the short arm was 12.00 (IQR 8-16) and 19.3 days in the long arm (IQR 14-26) (p = 0.008). A more pronounced self-efficacy correlated with earlier fulfillment of the objective discharge criteria (p = 0.048), whereas patients placing a high value on their health needed more time (p = 0.049).

CONCLUSION

The expectation of a shorter length of stay results in a quicker objective, physical patient convalescence after major liver resections.

A novel blinding protocol to test participant and therapist blinding during dry needling: a randomised controlled experiment

OBJECTIVES

Dry needling is widely used in physiotherapy. Lack of blinding in clinical trials means that dry needling effects and mechanisms remain unclear, with blinding issues accepted as an unavoidable barrier to better evidence. The authors aimed to overcome this barrier by designing a protocol to double-blind dry needling trials.

DESIGN

A prospectively registered randomised experiment tested a novel blinding protocol for blinding effectiveness.

SETTING

University physiotherapy clinic.

PARTICIPANTS

Therapists (n=15) and asymptomatic volunteers ('recipients') (n=45) were randomly allocated to real and/or sham interventions.

INTERVENTIONS

The protocol involved custom-made needles and cognitive and multisensory blinding techniques.

MAIN OUTCOME MEASURES

The primary outcome was guesses about allocation. The a priori criterion for successful blinding was ≤50% correct guesses (random chance). Secondary analyses explored blinding patterns using blinding indices.

RESULTS

Correct guesses were not different from 50% for therapists [41% (95%CI 30 to 50), n=120 guesses] or recipients [49% (95%CI 38 to 60), n=90 guesses]. Blinding indices supported the primary result but revealed that recipients were better at detecting real dry needling than sham.

CONCLUSION

Both therapists and recipients were successfully blinded, which contrasts with the widely held assumption that double-blinding is impossible for needling interventions. The authors recommend that any future trials can, and therefore should, blind therapists. However, secondary analyses revealed that recipients receiving real dry needling were less blinded than sham recipients, which may still create bias in clinical trials and suggests further work is needed to improve recipient blinding. Nonetheless, the current findings offer an opportunity to gain better evidence concerning the effects and mechanisms of dry needling.

STUDY REGISTRATION

https://osf.io/rkzeb/.

Effect of Briefing on Acupuncture Treatment Outcome Expectations, Pain, and Adverse Side Effects Among Patients With Chronic Low Back Pain: A Randomized Clinical Trial

IMPORTANCE

In observational studies, patients' treatment outcome expectations have been associated with better outcomes (ie, a placebo response), whereas concerns about adverse side effects have been associated with an in increase in the negative effects of treatments (ie, a nocebo response). Some randomized trials have suggested that communication from clinicians could affect the treatment outcomes by changing patients' expectations.

OBJECTIVE

To investigate whether treatment outcome expectations and reported adverse side effects could be affected by different briefing contents before a minimal acupuncture treatment in patients with chronic low back pain (CLBP).

DESIGN, SETTING, AND PARTICIPANTS

This randomized single-blinded clinical trial was conducted among patients with CLBP at 1 outpatient clinic in Switzerland who had a pain intensity of at least 4 on a numeric rating scale from 0 to 10. Different recruitment channels were used to enroll patients. Data were collected from May 2016 to December 2017 and were analyzed from June to November 2018.

INTERVENTIONS

Patients were randomized to receive either a regular expectation briefing or a high expectation briefing (effectiveness) and either a regular adverse side effect briefing or an intense adverse side effect briefing (adverse side effect) in a 2 × 2 factorial design. The intervention (briefing sessions and written materials) was standardized and delivered before the acupuncture treatment, with additional booster informative emails provided during the 4-week, 8-session acupuncture course.

MAIN OUTCOMES AND MEASURES

The primary end point was the patients' expectations regarding the effectiveness of the acupuncture treatment (Expectation for Treatment Scale [ETS]) after the briefing and the subsequent pain intensity (numeric rating scale). The primary end point for the adverse side effect briefing was the adverse side effect score at the end of the acupuncture treatment, derived from session-by-session assessments of adverse side effects.

RESULTS

A total of 152 patients with CLBP (mean [SD] age, 39.54 [12.52] years; 100 [65.8%] women) were included. The estimated group difference (regular vs high) for the ETS was -0.16 (95% CI -0.81 to 0.50, P = .64), indicating no evidence for a difference between intervention groups. There was also no evidence for a difference in pain intensity at the end of the acupuncture treatment between the groups with different expectation briefings. The adverse side effects score in the group with the intense adverse side effect briefing were estimated to be 1.31 times higher (95% CI, 0.94 to 1.82; P = .11) than after a regular adverse side effect briefing, but the finding was not statistically significant.

CONCLUSIONS AND RELEVANCE

In this study, suggestions regarding treatment benefits (placebo) and adverse side effects (nocebo) did not affect treatment expectations or adverse side effects. Information regarding adverse side effects might require more research to understand nocebo responses.

TRIAL REGISTRATION

German Clinical Trials Register Identifier: DRKS00010191.

How does semantic pain and words condition pain perception? A short communication

INTRODUCTION AND SCOPE

Language is one of the main tools with whom people describe their pain. The semantic value of words plays a fundamental role in the pain perception, intended as a complex process of modulation and processing in the brain. The priming effect is a cognitive process in which a certain stimulus can influence subsequent stimuli. It is therefore plausible that this effect plays a key role in the modulation and perception of pain. This study aimed to investigate the potential relationship between the semantic aspects of language, the priming effect, and the perception of pain.

METHODS AND RESULTS

A narrative review of the literature was conducted. Sixteen studies were included and categorized in four groups based on the effect of the verbal suggestion on the experimental acute pain and chronic pain and on the effect of pain-related words in free pain and post-surgical subjects.

CONCLUSIONS

There may be a link between language and pain, both at the behavioral and neural level. The processing of semantic information associated with pain influences the pain perception.

Blinding and expectancy confounds in psychedelic randomized controlled trials

Introduction: There is increasing interest in the potential for psychedelic drugs such as psilocybin, LSD and ketamine to treat several mental health disorders, with a growing number of randomized controlled trials (RCTs) being conducted to investigate the therapeutic effectiveness of psychedelics.Areas covered: We review previous literature on expectancy effects and blinding in the context of psychedelic RCTs - literature which strongly suggest that psychedelic RCTs might be confounded by de-blinding and expectancy. We conduct systematic reviews of psychedelic RCTs using Medline, PsychInfo and EMBASE (Jan 1990 - Nov 2020) and show that currently reported psychedelic RCTs have generally not reported pre-trial expectancy, nor the success of blinding procedures.Expert opinion: While psychedelic RCTs have generally shown promising results, with large effect sizes reported, we argue that treatment effect sizes in psychedelic RCTs are likely over-estimated due to de-blinding of participants and high levels of response expectancy. We suggest that psychedelic RCTs should routinely measure de-blinding and expectancy. Careful attention should be paid to clinical trial design and the instructions given to participants to allow these confounds to be reduced, estimated and removed from effect size estimates. We urge caution in interpreting effect size estimates from extant psychedelic RCTs.

What sixty years of research says about the effectiveness of patient education on health: a second order meta-analysis

Although meta-analyses have examined the association between patient education and health, the validity and quality of this evidence have not been comprehensively assessed. This second order meta-analysis combined previous meta-analyses that examined the effectiveness of patient education on health outcomes as an overall weighted grand mean d¯¯. Further, measures of methodological quality, meaningful variability across first order meta-analyses, and evidence for publication bias were examined. Forty meta-analyses were identified, investigating 156 associations between patient education and health summarizing data from over 776 studies including more than 74.947 patients. Quantitative analyses showed that patient education positively affects health outcomes with d¯¯ = 0.316 (95% CI [0.304, 0.329]). Summarizing data exclusively from randomized controlled trials indicated a causal effect. Patient education was effective for patients with neoplasms, diabetes, mental and behavioral disorders, diseases of the circulatory system, the respiratory system, and the musculoskeletal system. Patient education was effective in the reduction of medication use, pain, and visits to medical facilities, and significantly improved physiological, physical, psychological outcomes, and patients' general function. Overall, the findings reveal firm evidence for the effectiveness of patient education on health outcomes. However, theory-based interventions are lacking and need to be implemented to enable a successful transfer from theory to practice.

Progress of Acupuncture Therapy in Diseases Based on Magnetic Resonance Image Studies: A Literature Review

The neural mechanisms of acupuncture are not well-understood. Over the past decades, an increasing number of studies have used MRI to investigate the response of the brain to acupuncture. The current review aims to provide an update on acupuncture therapy in disease. The PubMed, Embase, Web of Science, and Cochrane Library databases were searched from inception to January 31, 2021. Article selection and data extraction were conducted by two review authors. A total of 107 publications about MRI in acupuncture were included, the collective findings of which were as follows: (1) stroke and GB34 (Yanglingquan) are the most studied disease and acupoint. Related studies suggested that the mechanism of acupuncture treatment for stroke may associate with structural and functional plasticity, left and right hemispheres balance, and activation of brain areas related to movement and cognition. GB34 is mainly used in stroke and Parkinson's disease, which mainly activates brain response in the premotor cortex, the supplementary motor area, and the supramarginal gyrus; (2) resting-state functional MRI (rs-fMRI) and functional connectivity (FC) analysis are the most frequently used approaches; (3) estimates of efficacy and brain response to acupuncture depend on the type of sham acupuncture (SA) used for comparison. Brain processing after acupuncture differs between patients and health controls (HC) and occurs mainly in disorder-related areas. Factors that influence the effect of acupuncture include depth of needling, number and locations of acupoints, and deqi and expectation effect, each contributing to the brain response. While studies using MRI have increased understanding of the mechanism underlying the effects of acupuncture, there is scope for development in this field. Due to the small sample sizes, heterogeneous study designs, and analytical methods, the results were inconsistent. Further studies with larger sample sizes, careful experimental design, multimodal neuroimaging techniques, and standardized methods should be conducted to better explain the efficacy and specificity of acupuncture, and to prepare for accurate efficacy prediction in the future.

Lay perspectives of the open-label placebo rationale: a qualitative study of participants in an experimental trial

OBJECTIVES

To analyse participants' concepts about the open-label placebo (OLP) effect; to explore their views about the discussion points that are applied in conventional OLP trials and to examine their experiences of taking part in an OLP trial.

DESIGN

A qualitative study using thematic analysis of semistructured interviews that were nested within a randomised controlled trial investigating experimental OLP analgesia (registered at ClinicalTrials.gov: NCT02578420).

PARTICIPANTS

30 healthy adults who took part in the randomised controlled trial.

RESULTS

Participants mostly conceptualised placebo as something that is inert and requires deception in order to be effective. Interviewees used a broad definition of placebos, going beyond a conventional notion of sugar pills. In contrast to the conventional OLP rationale, participants seldom emphasised classical conditioning as a mechanism of placebo effects, stressing a variety of other well-established components through which placebos might be therapeutic, whereas the conventional OLP disclosures state that 'a positive attitude helps but is not necessary', participants in our study applied other attitudes, such as 'it's worth a try'. When asked about their experiences during the trial, the majority emphasised that the concept of OLP was completely novel to them. Participants were rather sceptical about the efficacy of the intervention.

CONCLUSION

Integrating lay perspectives into the scientific rationale of OLP treatments might enhance the plausibility and credibility of the rationale in ethical treatments.

TRIAL REGISTRATION NUMBER

NCT02578420.

Education With Therapeutic Alliance Did Not Improve Symptoms in Patients With Chronic Low Back Pain and Low Risk of Poor Prognosis Compared to Education Without Therapeutic Alliance: A Randomized Controlled Trial

OBJECTIVES

To compare the effectiveness of an education intervention with or without the addition of the therapeutic alliance to no education intervention in patients with nonspecific chronic low back pain (LBP) and low risk of poor prognosis.

DESIGN

Randomized controlled trial. Randomization was performed using randomly generated numbers.

METHODS

Two hundred twenty-two patients with nonspecific chronic LBP and low risk of poor prognosis from 2 university physical therapy services in Taubaté, Brazil were randomized into 3 groups: education plus therapeutic alliance, education only, and no education. Primary outcomes were pain (measured with the numeric pain-rating scale) and patient-specific disability (measured with the Patient-Specific Functional Scale), assessed 1 month after randomization. The patients, therapists, and assessors were not blinded due to the nature of the intervention and self-reported outcomes.

RESULTS

Patients were recruited between November 2015 and February 2017. There was a loss of 17 (7.6%) follow-up assessments at 1 month, 28 (12.6%) at 6 months, and 31 (13.9%) at 12 months after randomization, and intention-to-treat analyses were conducted. There were no significant differences in pain between groups. However, there was a significant improvement in patient-specific disability for the education-plus-therapeutic alliance and education-only groups compared to no education after 1 month (mean difference, -1.41; 95% confidence interval: -2.31, -0.51 and -0.95; 95% confidence interval: -1.85, -0.04, respectively).

CONCLUSION

An education intervention did not provide clinically relevant improvements in patient-specific disability and did not influence pain in patients with nonspecific chronic LBP and low risk of poor prognosis. Additionally, there was no difference between interventions with or without emphasis on the therapeutic alliance. J Orthop Sports Phys Ther 2021;51(8):392-400. Epub 7 May 2021. doi:10.2519/jospt.2021.9636.

Placebo response and effect in randomized clinical trials: meta-research with focus on contextual effects

BACKGROUND

Contextual effects (i.e., placebo response) refer to all health changes resulting from administering an apparently inactive treatment. In a randomized clinical trial (RCT), the overall treatment effect (i.e., the post-treatment effect in the intervention group) can be regarded as the true effect of the intervention plus the impact of contextual effects. This meta-research was conducted to examine the average proportion of the overall treatment effect attributable to contextual effects in RCTs across clinical conditions and treatments and explore whether it varies with trial contextual factors.

METHODS

Data was extracted from trials included in the main meta-analysis from the latest update of the Cochrane review on "Placebo interventions for all clinical conditions" (searched from 1966 to March 2008). Only RCTs reported in English having an experimental intervention group, a placebo comparator group, and a no-treatment control group were eligible.

RESULTS

In total, 186 trials (16,655 patients) were included. On average, 54% (0.54, 95%CI 0.46 to 0.64) of the overall treatment effect was attributable to contextual effects. The contextual effects were higher for trials with blinded outcome assessor and concealed allocation. The contextual effects appeared to increase proportional to the placebo effect, lower mean age, and proportion of females.

CONCLUSION

Approximately half of the overall treatment effect in RCTs seems attributable to contextual effects rather than to the specific effect of treatments. As the study did not include all important contextual factors (e.g., patient-provider interaction), the true proportion of contextual effects could differ from the study's results. However, contextual effects should be considered when assessing treatment effects in clinical practice.

TRIAL REGISTRATION

PROSPERO CRD42019130257 . Registered on April 19, 2019.

Sensory Adaptation Training or Escitalopram for IBS With Constipation and Rectal Hypersensitivity: A Randomized Controlled Trial

INTRODUCTION

Rectal hypersensitivity is an important pathophysiological dysfunction in irritable bowel syndrome with predominant constipation (IBS-C), whose treatment remains challenging. In a randomized controlled trial, we compared the efficacy and safety of a novel sensori-behavioral treatment, sensory adaptation training (SAT) with escitalopram.

METHODS

Patients with IBS-C (Rome III) with rectal hypersensitivity received 6 biweekly sessions of SAT or escitalopram 10 mg daily for 3 months. SAT was performed by repetitive gradual distension of 10-cm long highly compliant rectal balloon above tolerability thresholds using barostat. Treatment effects on sensory thresholds and symptoms were compared. Coprimary outcome measures were those achieving improvements in rectal hypersensitivity (≥20% increase in ≥2/3 sensory thresholds) and pain (≥30% decrease).

RESULTS

We randomized 49 patients; 26 received SAT and 23 escitalopram. SAT significantly improved desire to defecate (Δ 13.5 ± 2.3 vs 2.2 ± 1.1 mm Hg, P = 0.0006) and maximum tolerability (Δ 14.8 ± 1.9 vs 1.6 ± 0.9 mm Hg, P < 0.0001) thresholds compared with escitalopram. There were significantly greater percentage of hypersensitivity responders with SAT than escitalopram (69% vs 17%, P < 0.001), but not pain responders (58% vs 44%, P = 0.4). Daily pain scores did not differ between groups (P = 0.8) or escitalopram (P = 0.06) but decreased with SAT (P = 0.0046) compared with baseline. SAT significantly increased rectal compliance (P < 0.019) and complete spontaneous bowel movements per week than escitalopram (P = 0.04). Five withdrew from adverse events with escitalopram and none with SAT.

DISCUSSION

SAT was significantly more efficacious in improving hypersensitivity and bowel symptoms in IBS-C than escitalopram. SAT is a promising novel treatment for IBS with rectal hypersensitivity.

Combination of acupuncture and medical training therapy on tension type headache: Results of a randomised controlled pilot study

OBJECTIVES

The aim of this study was to compare the effects of acupuncture and medical training therapy alone and in combination with those of usual care on the pain sensation of patients with frequent episodic and chronic tension-type headache.

DESIGN

This was a prospective single-centre randomised controlled trial with four balanced treatment arms. The allocation was carried out by pre-generated randomisation lists in the ratio 1:1:1:1 with different permutation block sizes.

SETTING

The study was undertaken in the outpatient clinic of Rehabilitation Medicine of the Hannover Medical School.Participants and interventions: Ninety-six adult patients with tension-type headache were included and randomised into usual care (n = 24), acupuncture (n = 24), medical training (n = 24), and combination of acupuncture and medical training (n = 24). One patient was excluded from analysis because of withdrawing her/his consent, leaving 95 patients for intention to treat analysis. Each therapy arm consisted of 6 weeks of treatment with 12 interventions. Follow-up was at 3 and 6 months.

MAIN OUTCOME MEASURES

Pain intensity (average, maximum and minimum), frequency of headache, responder rate (50% frequency reduction), duration of headache and use of headache medication.Clinical results: The combination of acupuncture and medical training therapy significantly reduced mean pain intensity compared to usual care (mean = -38%, standard deviation = 25%, p = 0.012). Comparable reductions were observed for maximal pain intensity (-25%, standard deviation = 20%, 0.014) and for minimal pain intensity (-35%, standard deviation = 31%, 0.03). In contrast, neither acupuncture nor medical training therapy differed significantly from usual care. No between-group differences were found in headache frequency, mean duration of headache episodes, and pain medication intake. At 3 months, the majority of all patients showed a reduction of at least 50% in headache frequency. At 6 months, significantly higher responder rates were found in all intervention groups compared to usual care.

CONCLUSIONS

In contrast to monotherapy, only the combination of acupuncture and medical training therapy was significantly superior in reduction of pain intensity compared to usual care.Trial registration: Registered on 11 February 2019. German Clinical Trials Register, DRKS00016723.

Blinding in Clinical Trials: Seeing the Big Picture

Blinding mitigates several sources of bias which, if left unchecked, can quantitively affect study outcomes. Blinding remains under-utilized, particularly in non-pharmaceutical clinical trials, but is often highly feasible through simple measures. Although blinding is generally viewed as an effective method by which to eliminate bias, blinding does also pose some inherent limitations, and it behooves clinicians and researchers to be aware of such caveats. This article will review general principles for blinding in clinical trials, including examples of useful blinding techniques for both pharmaceutical and non-pharmaceutical trials, while also highlighting the limitations and potential consequences of blinding. Appropriate reporting on blinding in trial protocols and manuscripts, as well as future directions for blinding research, will also be discussed.

Healing in a Social Context: The Importance of Clinician and Patient Relationship

When a patient presents to a health provider, the course of the disorder is composed of three effects: natural effects, specific effects, and contextual effects. Part of the contextual effect is due to the relationship between the healer and the patient. Social healing appears to be present in eusocial species and particularly well-developed in humans. Evidence for the importance of the relationship in healing is found in placebo studies, including placebo analgesics, medicine, and psychotherapy. Although the theory for how the relationship is therapeutic is not well-developed, four possible mechanisms are discussed. The implications for health care and the treatment of pain are discussed.

Placebo Effects on Stress, but Not on Pain Reports. A Multi-Experiment Study

Background

Contextual factors, such as participant/experimenter sex may moderate the placebo effects. We tested whether the participant and experimenter sex modulated placebo effects on experimentally induced pain and associated stress.

Objective

To investigate if (i) participant sex and (ii) experimenter sex influence placebo analgesia and subjective and physiological stress in two experiments employing a within-subjects and a mixed design, respectively. Placebo effects were investigated in pain reports, stress, and blood pressure.

Methods

Participants received painful stimulations and a placebo cream. In Experiment One (N = 59) participants underwent a placebo condition (PC) and a natural history condition (NHC) in random order. A placebo cream was applied in the PC and then the heat stimulation temperature was surreptitiously lowered. Identical stimulations were administered in the NHC, but with no cream, no information, and no lowered temperature. In Experiment Two, participants (N = 93) were randomly assigned to three groups receiving either a placebo cream with surreptitiously lowered intensity of electric stimuli (Placebo, PG), a placebo cream (Cream-Control, CCG) without changing the stimuli, or lowered intensity, but with no cream (Pain-Control, PCG) in a mixed design. All participants in both experiments received the same stimuli in the post-test as in the pre-test. Four experimenters (two females) in Experiment One, and five experimenters (two females) in Experiment Two conducted the studies.

Results

No placebo effect was seen on pain. However, there were placebo effects on stress, moderated by participant and experimenter sex: in Experiment One males in the PC had lower diastolic blood pressure (DBP) compared to males in the NHC. Participants in the PC had lower DBP compared to the NHC when tested by a female. In Experiment Two, participants expected more cream effectiveness when a female experimenter administered it, and reported lower stress in the PG compared to the PCG when tested by females.

Conclusion

Our findings highlight a distinction between placebo effects on pain and on associated stress. Secondly, female experimenters recorded lower physiological and subjective stress, higher effectiveness expectations, and lower pain from both sexes compared to male experimenters. Possible reasons for the failure to find a pain placebo effect are discussed.

Expectations about pain and analgesic treatment are shaped by medical providers' facial appearances: Evidence from five online clinical simulation experiments

RATIONALE

There is a robust link between patients' expectations and clinical outcomes, as evidenced by the placebo effect. Expectations depend in large part on the context surrounding treatment, including the patient-provider interaction. Prior work indicates that providers' behavior and characteristics, including warmth and competence, can shape patient outcomes. Yet humans rapidly form trait impressions of others before any in-person interaction. It is unknown whether these first impressions influence subsequent health care choices and expectations.

OBJECTIVE

Our goal was to test whether trait impressions of hypothetical medical providers, based exclusively on facial images, influence the choice of medical providers and expectations about pain and analgesia following hypothetical painful medical procedures.

METHOD

Across five online experiments, participants (total N = 1108) viewed and made judgments about hypothetical healthcare providers. Experiments 1-4 included computer-generated faces that varied in features associated with competence, while experiment 5 included real faces. We measured how apparent competence affected expectations about pain and anticipated analgesic use in all studies. We also measured warmth and similarity.

RESULTS

Across five online studies, participants selected providers who appeared more competent, based on facial visual information alone. Further, providers' apparent competence predicted participants' expectations about post-procedural pain and medication use. Participants' perception of their similarity to providers also shaped expectations about pain and treatment outcomes.

CONCLUSIONS

Results from our experimental simulations suggest that humans develop expectations about pain and health outcomes before even setting foot in the clinic, based exclusively on first impressions. These findings have strong implications for health care, as individuals increasingly rely on digital services to select healthcare providers and even receive treatment, a trend that is exacerbated as the world embraces telemedicine.

Placebo From an Enactive Perspective

Due to their complexity and variability, placebo effects remain controversial. We suggest this is also due to a set of problematic assumptions (dualism, reductionism, individualism, passivity). We critically assess current explanations and empirical evidence and propose an alternative theoretical framework-the enactive approach to life and mind-based on recent developments in embodied cognitive science. We review core enactive concepts such as autonomy, agency, and sense-making. Following these ideas, we propose a move from binary distinctions (e.g., conscious vs. non-conscious) to the more workable categories of reflective and pre-reflective activity. We introduce an ontology of individuation, following the work of Gilbert Simondon, that allow us to see placebo interventions not as originating causal chains, but as modulators and triggers in the regulation of tensions between ongoing embodied and interpersonal processes. We describe these interrelated processes involving looping effects through three intertwined dimensions of embodiment: organic, sensorimotor, and intersubjective. Finally, we defend the need to investigate therapeutic interactions in terms of participatory sense-making, going beyond the identification of individual social traits (e.g., empathy, trust) that contribute to placebo effects. We discuss resonances and differences between the enactive proposal, popular explanations such as expectations and conditioning, and other approaches based on meaning responses and phenomenological/ecological ideas.

Zusammenhänge zwischen Empathie, therapeutischer Haltung und Wirkeffizienz

Empathisch sein heißt, fühlen und verstehen können, was andere fühlen. Vermuten zu können, was das Gegenüber fühlt, denkt und wünscht, beruht auf der Fähigkeit, eigene Gefühle und Gedanken als getrennt von jenen anderer wahrnehmen und regulieren zu können. Definierte Therapieerfolge mit adäquatem Aufwand erreichen zu können, verlangt ein Fokussieren auf Wesentliches und Wichtiges. Die Empathie ist im Bereich der Psychotherapie jener Faktor, für den für sich genommen die höchste Effektstärke nachgewiesen werden konnte. Empathietraining ermöglicht eine bessere soziale Performance. Im Falle von Defiziten in sozialer Kompetenz ist störungsunabhängig ein besonders hoher Leidensdruck nachweisbar.

Pharmacologic Treatment in Functional Abdominal Pain Disorders in Children: A Systematic Review

CONTEXT

Functional abdominal pain disorders (FAPDs) are common in childhood, impacting quality of life and school attendance. There are several compounds available for the treatment of pediatric FAPDs, but their efficacy and safety are unclear because of a lack of head-to-head randomized controlled trials (RCTs).

OBJECTIVE

To systematically review the efficacy and safety of the pharmacologic treatments available for pediatric FAPDs.

DATA SOURCES

Electronic databases were searched from inception to February 2021.

STUDY SELECTION

RCTs or systematic reviews were included if the researchers investigated a study population of children (4-18 years) in whom FAPDs were treated with pharmacologic interventions and compared with placebo, no treatment, or any other agent.

DATA EXTRACTION

Two reviewers independently performed data extraction and assessed their quality. Any interresearcher disagreements in the assessments were resolved by a third investigator.

RESULTS

Seventeen articles representing 1197 children with an FAPD were included. Trials investigating antispasmodics, antidepressants, antibiotics, antihistaminic, antiemetic, histamine-2-receptor antagonist, 5-HT4-receptor agonist, melatonin, and buspirone were included. No studies were found on treatment with laxatives, antidiarrheals, analgesics, antimigraines, and serotonergics.

LIMITATIONS

The overall quality of evidence on the basis of the Grading of Recommendations, Assessment, Development and Evaluations system was very low to low.

CONCLUSIONS

On the basis of current evidence, it is not possible to recommend any specific pharmacologic agent for the treatment of pediatric FAPDs. However, agents such as antispasmodics or antidepressants can be discussed in daily practice because of their favorable treatment outcomes and the lack of important side effects. High-quality RCTs are necessary to provide adequate pharmacologic treatment. For future intervention trials, we recommend using homogenous outcome measures and instruments, a large sample size, and long-term follow-up.

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.

Does the placebo effect on hot flashes depend on the placebo dose?

PURPOSE

To investigate the presence of a placebo dose-response effect in four randomized, double-blind, placebo-controlled, multi-dose hot flash clinical trials conducted at Mayo Clinic.

METHODS

Hot flash score, frequency, and hot flash-related distress for each placebo dose level were summarized at each time point by mean and standard deviation and changes from baseline were plotted to visualize a possible placebo dose-effect response. Furthermore, a meta-analysis was conducted for each endpoint in the highest and lowest dosage arms across the four trials.

RESULTS

Longitudinal plots of mean hot flash scores, frequencies, and hot flash-related distress scores in patients taking placebo in each study showed a decline in hot flash scores over time without any clinically meaningful differences between the lowest and highest dosage arms in each study. The meta-analysis for each endpoint in the highest and lowest dosage arms across the four trials revealed no clinically important differences either.

CONCLUSION

While the current study cannot rule out the existence of a placebo dose-response effect in multi-dose placebo-controlled trials in patients with hot flashes or other conditions, it suggests, along with the available data in the placebo literature, that, at least in well-conducted multi-dose clinical trials in which the placebo was used as control, such an effect, if it exists at all, should be very small. Therefore, pooling data from different placebo subgroups is unlikely to compromise the validity of comparisons between the combined placebo arms and each treatment arm.

Electroacupuncture vs Prucalopride for Severe Chronic Constipation: A Multicenter, Randomized, Controlled, Noninferiority Trial

INTRODUCTION

This multicenter, randomized, noninferiority trial compared electroacupuncture with prucalopride for the treatment of severe chronic constipation (SCC).

METHODS

Participants with SCC (≤ 2 mean weekly complete spontaneous bowel movements [CSBMs]) were randomly assigned to receive either 28-session electroacupuncture over 8 weeks with follow-up without treatment over 24 weeks or prucalopride (2 mg/d before breakfast) over 32 weeks. The primary outcome was the proportion of participants with ≥3 mean weekly CSBMs over weeks 3-8, based on the modified intention-to-treat population, with -10% as the noninferior margin.

RESULTS

Five hundred sixty participants were randomized, 280 in each group. Electroacupuncture was noninferior to prucalopride for the primary outcome (36.2% vs 37.8%, with a difference of -1.6% [95% confidence interval, -8% to 4.7%], P < 0.001 for noninferiority); almost the same results were found in the per-protocol population. The proportions of overall CSBM responders through weeks 1-8 were similar in the electroacupuncture and prucalopride groups (24.91% vs 25.54%, with a difference of -0.63% [95% confidence interval, -7.86% to 6.60%, P = 0.864]). Except during the first 2-week treatment, no between-group differences were found in outcomes of excessive straining, stool consistency, and quality of life. Adverse events occurred in 49 (17.69%) participants in the electroacupuncture group and 123 (44.24%) in the prucalopride group. One non-treatment-related serious adverse event was recorded in the electroacupuncture group.

DISCUSSION

Electroacupuncture was noninferior to prucalopride in relieving SCC with a good safety profile. The effects of 8-week electroacupuncture could sustain for 24 weeks after treatment. Electroacupuncture is a promising noninferior alternative for SCC (see Visual Abstract, http://links.lww.com/AJG/B776).

A double-blind study of empathic support and expectation as mechanisms of symptom change

Objective: A novel brief intervention was used to investigate how empathic support and expectation can induce changes in mood, anxiety, and perceived stress. Method: Seventy-six undergraduates with high negative affect were assigned to three conditions of a program involving tasks with no known therapeutic benefit. In Group 1: Expectation Only, participants were given a deceptive description of the benefits of the program to quantify the magnitude of symptom change due to expectation alone. In Group 2: Empathic Support + Expectation, participants were also instructed to write about past and current sources of distress and provided with supportive notes each week to quantify the role of empathic support plus expectation. In Group 3: Control, participants were told they were "norming" the instruments. Results: Participants in Groups 1 and 2 demonstrated decreases in depression, anxiety, and rumination, with significant medium effect reductions found in the empathic support plus expectation condition. Conclusions: Evidence suggests that empathic support and expectation cause reduction of symptoms spanning depression and anxiety.

Nonpharmacological Interventions for Pediatric Migraine: A Network Meta-analysis

CONTEXT

Migraine is a common neurologic disorder in children and adolescents. However, a comparison of multiple nonpharmacological treatments is lacking.

OBJECTIVE

To examine whether nonpharmacological treatments are more effective than waiting list and whether there are differences between interventions regarding efficacy.

DATA SOURCES

Systematic review and network meta-analysis of studies in Medline, Cochrane, Embase, and PsycINFO published through August 5, 2019.

STUDY SELECTION

Randomized controlled trials of nonpharmacological treatments in children and adolescents diagnosed with episodic migraine.

DATA EXTRACTION

Effect sizes, calculated as standardized mean differences (SMDs) for the primary outcome efficacy, were assessed in a random-effects model.

RESULTS

Twelve studies (N = 576) were included. When interventions were classified into groups on the basis of similarity of treatment components, self-administered treatments, biofeedback, relaxation, psychological treatments, and psychological placebos were significantly more effective than waiting list with effect sizes ranging between SMD = 1.14 (95% confidence interval, 0.09 to 2.19) for long-term psychological placebos to SMD = 1.44 (95% confidence interval, 0.26 to 2.62) for short-term self-administered treatments. However, when all interventions were examined individually (ie, 1 node per intervention), none were significantly more effective compared with waiting list, mainly because of lack of statistical power.

LIMITATIONS

Because of our focus on pediatric migraine, only a small number of studies could be included.

CONCLUSIONS

Our findings reveal that components of nonpharmacological interventions are effective in treating pediatric migraine. Some effects have to be interpreted carefully because they are based on small studies. Future researchers should identify factors associated with individual responses in large, multicentered studies.