A comprehensive review of the placebo effect: recent advances and current thought

Efficacy and safety of acupuncture monotherapy or combined with pelvic floor muscle training for female stress urinary incontinence: a systematic review and meta-analysis

Background

Stress urinary incontinence (SUI) is involuntary urine leakage during effort. Pelvic floor muscle training (PFMT) is a common physical therapy for SUI, but has low adherence and its long-term effectiveness is uncertain. Drug therapy has side-effect problems and surgery has risks. Acupuncture's role in improving SUI is also unclear based on previous studies.

Objectives

This systematic review and meta-analysis evaluated the efficacy and safety of acupuncture individually or combined with PFMT in improving symptoms and women's health-related quality of life of SUI.

Design

A systematic review and meta-analysis were conducted.

Patients

Women with stress urinary incontinence were treated with electroacupuncture (EA) individually or acupuncture combined with PFMT.

Results

In the analysis comparing urinary leakage 1 h and the ICIQ-SF score, electroacupuncture (EA) intervention was significantly associated with improvements in both urine leakage (MD = 4.69, 95% CI 2.83 to 6.55, I2 = 62%) and ICIQ-SF (MD = 2.61, 95% CI 1.64 to 3.58, I2 = 65%). The results were robust for the sensitivity analyses. EA was not associated with an increased incidence of adverse events compared to placebo EA (RR = 1.08, 95% CI 0.50 to 2.35, I2 = 0%). When comparing the group receiving pelvic floor muscle training (PFMT) combined with acupuncture to the PFMT only group, the combination therapy was found to improve urine leakage 1 h (MD = 1.91, 95% CI 0.96 to 2.86, I2 = 80%) and improve ICIQ-SF (MD = 2.63, 95% CI 1.60 to 3.65, I2 = 75%) in patients with SUI, despite significant heterogeneity observed. Subgroup analyses based on urine leakage 1 h revealed that subjects with mild stress urinary incontinence showed improvements (MD = 1.46, 95% CI 0.82 to 2.10, I2 = 58%), as did those with moderate stress urinary incontinence (MD = 4.9, 95% CI 1.72 to 8.08, I2 = 77%). There were significant differences between these subgroups (I2 = 77%, p = 0.04). In the subgroup analysis of intervention types, manual acupuncture showed no significant effect when combined (MD = 1.11, 95% CI -0.61 to 2.83, I2 = 86%).

Conclusion

The findings from this meta-analysis indicate that EA is more effective at improving the clinical symptoms and quality of life in patients with SUI compared to placebo EA, and it does not increase the risk of adverse events. Moreover, the therapeutic effect of SUI treatment with EA combined with pelvic floor muscle training (PFMT) elicits a more positive response than PFMT alone. This suggests that EA, either as a standalone therapy or as an adjunct to PFMT, can offer beneficial outcomes for individuals with stress urinary incontinence, expanding the range of clinical treatment options available.

Systematic Review Registration

The meta-analysis was registered in PROSPERO (CRD42022381409).

The role of pain expectancy and its confidence in placebo hypoalgesia and nocebo hyperalgesia

ABSTRACT

Placebo hypoalgesia and nocebo hyperalgesia, which exemplify the impact of expectations on pain, have recently been conceptualised as Bayesian inferential processes, yet empirical evidence remains limited. Here, we explore whether these phenomena can be unified within the same Bayesian framework by testing the predictive role of expectations and their level of precision (ie, expectation confidence) on pain, with both predictors measured at the metacognitive level. Sixty healthy volunteers underwent a pain test (ie, 8 noxious electrical stimuli) before (Baseline) and after (T0, T1, T2) receiving a sham treatment associated with hypoalgesic (placebo), hyperalgesic (nocebo), or neutral (control) verbal suggestions, depending on group allocation. Trial-by-trial expectations, their precision, and perceived pain were measured. Skin conductance response (SCR) was also recorded as an autonomic response marker. Bayesian linear mixed models analyses revealed that, for both placebo and nocebo, pain was predicted by expectations alone and by their interaction with expectations precision. In addition, the discrepancy between expected and perceived pain was predicted by expectation precision, with greater alignment between expected and perceived pain when precision was higher. This suggests that both placebo and nocebo responses are well described from a Bayesian perspective. A main effect of time for SCR was observed, suggesting habituation to painful stimuli. Our data provide evidence indicating that both placebo hypoalgesia and nocebo hyperalgesia can be unified within the same Bayesian framework in which not only expectations but also their level of precision, both measured at the metacognitive level, are key determinants of the pain inferential process.

Subcutaneous Administration of Therapeutic Monoclonal Antibody Drug Products Using a Syringe in Blinded Clinical Trials: Advances and Key Aspects Related to Blinding/Matching/Masking Strategies for Placebo Formulation

Therapeutic monoclonal antibody (mAb) drug products are increasingly used to treat both chronic and acute diseases. These mAb drug products are often developed for subcutaneous (SC) injection to simplify dosing compared with intravenous (IV) infusion. For SC injection, the mAb liquid drug product is typically filled in a vial for use with a syringe or in a prefilled syringe, which can then be assembled into a safety syringe device or an autoinjector for direct administration. A placebo is an inert formulation (one without an active ingredient) that lacks pharmacological activity or a therapeutic effect. It serves as a control in blinded clinical trials to evaluate the efficacy of a new treatment. A suitable blinding/matching/masking strategy is crucial to ensure that study participants cannot distinguish between the active mAb formulation and the placebo. The success of these strategies is pivotal in ensuring the accuracy and reliability of clinical trial results. This Review summarizes recent advances and key considerations related to placebo strategies. It covers the benefits and challenges of SC injection of therapeutic mAbs compared to IV infusion, the placebo effect, the significance of blinding/matching/masking, and various strategies. Strategies discussed include the use of traditional placebos (e.g., normal saline, 5% w/v dextrose solution, and formulation buffer of the active mAb), syringe blinding, the use of different gauge syringe needles, novel (custom) placebos, dilution, independent administration, and multiple injections. Additional topics covered include the incidence of antidrug antibodies (ADAs), the benefits and challenges associated with different strategies, and regulatory expectations regarding custom placebos. By addressing these critical aspects, the Review aims to contribute to the growing body of knowledge and ongoing efforts to enhance the effectiveness of formulation blinding, matching, and masking in clinical trials.

Does a Prolonged Sham Theta Burst Stimulation Intervention Regimen Outperform Standard Care in Terms of Functional Recovery and Pain Relief After an Upper Limb Fracture?

OBJECTIVE

In a recent sham-controlled 13-session prolonged continuous theta burst stimulation intervention protocol, recovery from upper limb fracture at both 1 and 3 months was better than anticipated in patients assigned to the sham intervention group. To determine whether potential placebo effect and close patient monitoring affected recovery, the current study aimed to compare clinical outcomes between sham-treated participants who also received standard care with similarly injured patients who only received standard care.

METHODS

Twenty participants with isolated upper limb fractures from the sham group were seen 13 times post-fracture (1 baseline session, 10 treatments, and 2 follow-ups [1 and 3 months]) over 3 months. They completed the self-reported Disabilities of Arm, Shoulder, and Hand (DASH) questionnaire and the Numerical Rating Scale for pain assessment at 1 and 3 months post-fracture. Two control groups were recruited: 43 participants at 1 month post-fracture and another 40 participants at 3 months post-fracture. These control groups completed the same questionnaires online, without any lab visits.

RESULTS

At 1 month, patients from the sham group reported significantly less functional impairments on the DASH (p = .010). At 3 months, significantly more patients from the control group reported functional limitations (72.5% versus sham's 40%, p = .015).

CONCLUSIONS

Although preliminary, these findings suggest clinically significant beneficial effects of the sham intervention over the standard care groups. This positive sham intervention effect may be attributed to a placebo response that includes the placebo effect associated with sham rTMS, but also the impact of various factors such as the close monitoring of the injury.

Nutritional practices to manage menstrual cycle related symptoms: a systematic review

Certain nutritional practices may reduce menstrual-related symptoms, but there is no current consensus on what foods/supplements are sufficiently evidenced to warrant promotion to reduce menstrual symptoms of naturally menstruating individuals. This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Two online databases were searched for published experimental studies that investigated the effects of foods/supplements on menstrual-related symptoms in eumenorrhoeic women. Extracted data and study characteristics were tabulated and grouped on the basis of food/supplement intervention and dosage compared with UK dietary reference values (DRV) and safe upper limits. In total, twenty-eight studies and twenty-one different foods/supplement interventions were included in the review. None of the studies reported a negative effect on symptoms, twenty-three reported a positive effect and five had no effect. Eighteen different ways of measuring menstrual-related symptoms were described across the studies. The results indicate a lack of consistency in studies to confidently provide information to eumenorrheic, naturally menstruating women regarding the use of foods/supplements to reduce menstrual symptoms. Determination of menstrual-related symptoms varied along with dose and duration of food or supplements provided. These data provide some evidence for the use of vitamin D, calcium, zinc and curcumin to reduce menstrual-related symptoms of non-hormonal contraceptive users, on an individual basis; however, further investigation is required prior to implementation with a focus on robust protocols to determine and measure changes in menstrual symptoms, with interventions adhering to DRV and safe upper limits.

Nocebo Effect on Pain Perception and Attention with Children With and Without Attention Deficit And/Or Hyperactivity Disorder

OBJECTIVE

Attention deficit disorder with or without hyperactivity (ADHD) has negative consequences for children. The effectiveness of medical interventions and educational outcomes are strongly influenced by expectations, which can be modulated by nocebo effects. The aims of this study were to compare the nocebo effect on pain perception and attention in children with and without ADHD as well as to characterize the associations of the nocebo effect with personal variables, such as anxiety, sleep, and pain catastrophizing.

METHODS

Data were collected from 30 children with and without ADHD. The nocebo effect was induced using an inactive pill, "increasing" pain perception and attention deficits. Experimental thermal pain was evoked using a thermode and recorded using a computerized visual analog scale. Attention abilities were measured with the Stop-Signal Task. We also used questionnaires to measure personal variables.

RESULTS

When combining groups, the nocebo treatment led to comparable nocebo effects for pain (increased pain perception) and attention (increased time needed for inhibition). When comparing groups, the nocebo effect on pain perception was similar for children with and without ADHD. Inattention, learning problems, anxiety, and sleep problems were associated with the nocebo response for pain and attention.

CONCLUSION

This exploratory study conducted in an experimental setting emphasizes the importance of managing children's expectations for pain perception and attention as well as the potentially deleterious impact of negative suggestions on elementary school children.

Enhancing placebo analgesia: Unravelling the powerful interplay of ownership and verbal suggestion

BACKGROUND

Placebo analgesic research demonstrates pain reduction after using a placebo analgesic. Recent studies have documented that sometimes possessing a placebo analgesic induces placebo analgesia. These prior studies used a 'cream' as the stimulus and proposed that the effect is driven by an expectancy of obtaining benefits from the owned analgesic. This paper examines three pivotal components of placebo analgesia: placebo form, ownership and expectancy induced by verbal suggestion. We investigate analgesic expectancy between cream versus oil form of placebo stimulus and systematically isolate the effects of ownership, verbal suggestion and their interaction, comparing with the effect of use, to decipher the dynamics of placebo analgesia.

METHODS

Study 1 (N = 46) evaluated analgesic expectancy between cream and oil. Study 2 (N = 119) exposed participants to a placebo analgesic oil and randomized them into PU (possess and use), PA (possess and anticipate), P (possess-only) or A (anticipate-only) conditions. Pain outcomes were assessed using a cold pressor test. Comparing PA and P conditions assessed the verbal suggestion effect, comparing PA and A conditions evaluated the possession effect, while comparing PU and PA conditions shed light on the use effect.

RESULTS

In Study 1, participants showed comparable analgesic expectancy for cream and oil. In Study 2, both PA and PU groups performed equally well, reporting higher pain threshold, F(3, 115) = 5.14, p = 0.002,η p 2  = 0.12; and a greater probability of persistent hand submersion than P and A groups, X2(3) = 8.06, p = 0.045.

CONCLUSION

The findings highlight the significance of integrating possession with expectancy to induce placebo analgesia, which has clinical implications.

SIGNIFICANCE

This study delves into the intricate dynamics of placebo analgesia, shedding light on the significant influence of ownership and verbal suggestion. Through a meticulous exploration of the relationship between ownership and expectancy induced by verbal suggestion, we propose novel avenues for enhancing placebo responses. This research has implications for clinical practice and pain management strategies, potentially revolutionizing approaches to pain relief and therapeutic outcomes. Our findings contribute to a paradigm shift in understanding placebo analgesia, emphasizing the pivotal interaction between ownership and verbal suggestion.

Placebo effects in neuropathic pain conditions

Management of neuropathic pain is exceptionally challenging and development of new drugs and ways to optimize treatment effects in clinical practice are needed. Over the last decade, some of the mechanisms underlying placebo effects have been elucidated and some of the insights have the potential to improve the treatment for neuropathic pain. Research suggests that the increasing placebo responses observed in randomized controlled trials (RCTs) for neuropathic pain pose challenges for the development and availability of new effective pain medications. In neuropathic pain, these placebo responses are typically not controlled for the natural history of pain and other confounding factors. Thus, our knowledge about the magnitude and mechanisms of placebo effects in neuropathic pain is sparse. A few mechanistic studies investigating placebo effects by controlling for natural history of pain have found large placebo analgesia effects in neuropathic pain. Psychological factors such as expectations and emotions play a substantial role in inducing the placebo effects. Here, we review placebo effects and the psychological and neurobiological mechanisms contributing to the placebo effects. The knowledge obtained from studies of placebo mechanisms can help improve the information that can be obtained from RCTs and potentially improve development of new pain medications and optimize treatment of neuropathic pain in clinical practice.

Lightening the mind with audiovisual stimulation as an accessible alternative to breath-focused meditation for mood and cognitive enhancement

In this randomized, controlled, and double-blind experiment with a relatively large sample (n = 262), a novel technique of audiovisual stimulation (AVS) was demonstrated to substantially improve self-reported mood states by reducing several negative affects, including anxiety and depression, and enhancing performance on mood-sensitive cognitive tasks. Most of the AVS effects were highly similar whether binaural beats were present or not and regardless of the duration of experience. Remarkably, the mood benefits from AVS closely aligned with those achieved through breath-focused meditation with additional evidence that a brief AVS exposure of approximately five minutes may be sufficient or even optimal for improving mood to a comparable or greater degree than meditation sessions of equal or longer durations (11-22 min). These exciting findings position AVS as a promising avenue for mood and cognition enhancement and a potentially more accessible "plug-and-play" alternative to meditation, which is especially relevant considering the high attrition rates commonly observed in meditation practices.

The Role of Attention in Placebo and Nocebo Effects

BACKGROUND

Although some existing models propose that attention may be crucially implicated in placebo/nocebo effects, empirical research on this aspect remains limited and scattered.

PURPOSE

This systematic review aims to provide an inclusive overview of studies that have either directly manipulated or assessed attention within the context of placebo and nocebo procedures so to gain a synthetized picture of the role of this variable in placebo/nocebo effects. Importantly, only studies in which attention represented a mechanism or mediator of the placebo/nocebo response, and not a primary outcome, were included.

METHODS

A systematic search was conducted across multiple databases, including PubMed, Scopus, PsycINFO, Web of Science, and Embase, to identify peer-reviewed studies. These studies were subjected to methodological evaluation and eligibility criteria for inclusion.

RESULTS

We identified and classified 12 studies into three categories based on their focus: (i) those that directly assessed attention, (ii) those that directly manipulated participants' attention, and (iii) those that combined both a direct manipulation and assessment of attention. In all selected studies attention acted as a mechanism or mediator of the placebo/nocebo response, and was not considered a primary outcome of the placebo/nocebo manipulation.

CONCLUSIONS

The synthesis of the included studies reveals that the role of attention in placebo and nocebo effects is still a topic of debate, marked by variations in how attention is conceptualized and measured. Results suggest that attention has significant clinical implications, particularly in optimizing therapeutic efficacy by directing patients' focus toward signs of healing and away from indicators of illness or distress. To advance our understanding, future research should explore these attentional mechanisms, in conjunction with neurophysiological correlates.

Expectation generation and its effect on subsequent pain and visual perception

Bayesian accounts of perception, such as predictive processing, suggest that perceptions integrate expectations and sensory experience, and thus assimilate to expected values. Furthermore, more precise expectations should have stronger influences on perception. We tested these hypotheses in a paradigm that manipulates both the mean value and the precision of cues within-person. Forty-five participants observed cues-presented as ratings from 10 previous participants-with varying cue means, variances (precision), and skewness across trials. Participants reported expectations regarding the painfulness of thermal stimuli or the visual contrast of flickering checkerboards. Subsequently, similar cues were each followed by a visual or noxious thermal stimulus. While perceptions assimilated to expected values in both modalities, cues' precision mainly affected visual ratings. Furthermore, behavioral and computational models revealed that expectations were biased towards extreme values in both modalities, and towards low-pain cues specifically. fMRI analysis revealed that the cues affected systems related to higher-level affective and cognitive processes-including assimilation to the cue mean in a neuromarker of endogenous contributions to pain and in the nucleus accumbens, and activity consistent with aversive prediction-error-like encoding in the periaqueductal gray during pain perception-but not systems related to early perceptual processing. Our findings suggest that predictive processing theories should be combined with mechanisms such as selective attention to better fit empirical findings, and that expectation generation and its perceptual effects are mostly modality-specific and operate on higher-level processes rather than early perception.

Examining the association of vaccine-related mindsets and post-vaccination antibody response, side effects, and affective outcomes

Background

Although vaccines are largely effective and safe, there is variability in post-vaccination experience regarding antibody response, side effects, and affective outcomes. Vaccine mindsets, specific beliefs about the vaccine, may be associated with post-vaccination experience. This is important since mindsets are malleable and may help decrease vaccine hesitancy and improve post-vaccination experience.

Methods

In a prospective study, we measured overall positive vaccine mindset and specific mindsets regarding efficacy, body response, and side effects. We tested whether vaccine mindsets before vaccination predicted neutralizing antibody response, side effects, vaccine-related stress, and affective outcomes (general stress, sadness, and happiness). Antibody response was assessed one month and six months after participants completed a SARS-CoV-2 vaccination series. Side effect experience and affective reactions were assessed daily on the vaccination day and the subsequent five days.

Results

There was no significant association between the aggregate vaccine mindset score and neutralizing antibody response; however, people with a more positive vaccine mindset reported fewer side effects, less same-day vaccine-related anxiety, and improved affective outcomes after vaccination. In secondary analyses, when specific mindsets were explored, the mindset that vaccine side effects are a sign of treatment efficacy predicted higher antibodies, but not side effects experience and vaccine-related anxiety. Vaccine efficacy and body-response mindsets predicted fewer side effects, vaccine-related anxiety, and improved affective outcomes after vaccination.

Conclusion

These findings underscore the potential of vaccine mindsets in enhancing the overall post-vaccination experience and, in some cases, increasing antibody response.

Efficacy and safety of fentanyl inhalant for the treatment of breakthrough cancer pain: a multicenter, randomized, double-blind, placebo-controlled trial

BACKGROUND

Breakthrough cancer pain (BTcP) has a negative impact on patients' quality of life, general activities, and is related to worse clinical outcomes. Fentanyl inhalant is a hand-held combination drug-device delivery system providing rapid, multi-dose (25μg/dose) administration of fentanyl via inhalation of a thermally generated aerosol. This multicenter, randomized, placebo-controlled, multiple-crossover, double-blind study evaluated the efficacy, safety, and tolerability of fentanyl inhalant in treating BTcP in opioid-tolerant patients.

METHODS

The trial was conducted in opioid-tolerant cancer patients with 1 ~ 4 BTcP outbursts per day. Each patient was treated and observed for 6 episodes of BTcP (4 with fentanyl inhalant, 2 with placebo). During each episode of targeted BTcP, patients were allowed up to six inhalations, with an interval of at least 4 min between doses. Primary outcome was the time-weighted sum of PID (pain intensity difference) scores at 30 min (SPID30).

RESULTS

A total of 335 BTcP episodes in 59 patients were treated. The mean SPID30 was -97.4 ± 48.43 for fentanyl inhalant-treated episodes, and -64.6 ± 40.25 for placebo-treated episodes (p < 0.001). Significant differences in PID for episodes treated with fentanyl inhalant versus placebo was seen as early as 4 min and maintained for up to 60 min. The percentage of episodes reported PI (pain intensity) scores ≤ 3, a ≥ 33% or ≥ 50% reduction in PI scores at 30 min, PR30 (pain relief scores at 30 min) and SPID60 favored fentanyl inhalant over placebo. Only 4.4% of BTcP episodes required rescue medication in fentanyl inhalant group. Most AEs were of mild or moderate severity and typical of opioid drugs.

CONCLUSION

Treatment with fentanyl inhalant was shown to be a promising therapeutic option for BTcP, with significant pain relief starting very soon after dosing. Confirmation of effectiveness requires a larger phase III trial.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT05531422 registered on 6 September 2022 after major amendment, NCT04713189 registered on 14 January 2021.

Is non-invasive neuromodulation a viable technique to improve neuroplasticity in individuals with acquired brain injury? A review

Objective

This study aimed to explore and evaluate the efficacy of non-invasive brain stimulation (NIBS) as a standalone or coupled intervention and understand its mechanisms to produce positive alterations in neuroplasticity and behavioral outcomes after acquired brain injury (ABI).

Data sources

Cochrane Library, Web of Science, PubMed, and Google Scholar databases were searched from January 2013 to January 2024.

Study selection

Using the PICO framework, transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS) randomized controlled trials (RCTs), retrospective, pilot, open-label, and observational large group and single-participant case studies were included. Two authors reviewed articles according to pre-established inclusion criteria.

Data extraction

Data related to participant and intervention characteristics, mechanisms of change, methods, and outcomes were extracted by two authors. The two authors performed quality assessments using SORT.

Results

Twenty-two studies involving 657 participants diagnosed with ABIs were included. Two studies reported that NIBS was ineffective in producing positive alterations or behavioral outcomes. Twenty studies reported at least one, or a combination of, positively altered neuroplasticity and improved neuropsychological, neuropsychiatric, motor, or somatic symptoms. Twenty-eight current articles between 2020 and 2024 have been studied to elucidate potential mechanisms of change related to NIBS and other mediating or confounding variables.

Discussion

tDCS and TMS may be efficacious as standalone interventions or coupled with neurorehabilitation therapies to positively alter maladaptive brain physiology and improve behavioral symptomology resulting from ABI. Based on postintervention and follow-up results, evidence suggests NIBS may offer a direct or mediatory contribution to improving behavioral outcomes post-ABI.

Conclusion

More research is needed to better understand the extent of rTMS and tDCS application in affecting changes in symptoms after ABI.

Smartphone-Delivered Attentional Bias Modification Training for Mental Health: Systematic Review and Meta-Analysis

BACKGROUND

Smartphone-delivered attentional bias modification training (ABMT) intervention has gained popularity as a remote solution for alleviating symptoms of mental health problems. However, the existing literature presents mixed results indicating both significant and insignificant effects of smartphone-delivered interventions.

OBJECTIVE

This systematic review and meta-analysis aims to assess the impact of smartphone-delivered ABMT on attentional bias and symptoms of mental health problems. Specifically, we examined different design approaches and methods of administration, focusing on common mental health issues, such as anxiety and depression, and design elements, including gamification and stimulus types.

METHODS

Our search spanned from 2014 to 2023 and encompassed 4 major databases: MEDLINE, PsycINFO, PubMed, and Scopus. Study selection, data extraction, and critical appraisal were performed independently by 3 authors using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. When necessary, we pooled the standardized mean difference with a 95% CI. In addition, we conducted sensitivity, subgroup, and meta-regression analyses to explore moderator variables of active and placebo ABMT interventions on reducing symptoms of mental health problems and attentional bias.

RESULTS

Our review included 12 papers, involving a total of 24,503 participants, and we were able to conduct a meta-analysis on 20 different study samples from 11 papers. Active ABMT exhibited an effect size (Hedges g) of -0.18 (P=.03) in reducing symptoms of mental health problems, while the overall effect remained significant. Similarly, placebo ABMT showed an effect size of -0.38 (P=.008) in reducing symptoms of mental health problems. In addition, active ABMT (Hedges g -0.17; P=.004) had significant effects on reducing attentional bias, while placebo ABMT did not significantly alter attentional bias (Hedges g -0.04; P=.66).

CONCLUSIONS

Our understanding of smartphone-delivered ABMT's potential highlights the value of both active and placebo interventions in mental health care. The insights from the moderator analysis also showed that tailoring smartphone-delivered ABMT interventions to specific threat stimuli and considering exposure duration are crucial for optimizing their efficacy. This research underscores the need for personalized approaches in ABMT to effectively reduce attentional bias and symptoms of mental health problems.

TRIAL REGISTRATION

PROSPERO CRD42023460749; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=460749.

Placebo-related improvement with methylphenidate treatment in children with ADHD

Non-specific effects of methylphenidate treatment, including expectancy and regression to the mean effects, contribute to the overall effect of methylphenidate on attention-deficit/hyperactivity disorder (ADHD) symptoms. Knowledge on the extent to which non-specific effects contribute to the overall effect and whether regression to the mean explains part of the non-specific effects, is currently lacking. A double-blind, randomized, placebo-controlled, cross-over trial was used to compare parent and teacher ratings of child ADHD symptoms at baseline and during treatment with placebo and 5, 10, 15 and 20 mg of methylphenidate, twice daily. Participants were 5-13-year-old children with a DSM-5 diagnosis of ADHD (N = 45). The extent to which non-specific effects contributed to the effects of methylphenidate was determined by ADHD symptom reductions observed with placebo versus reductions observed with active doses of methylphenidate. The influence of regression to the mean was examined by estimating the contribution of baseline ADHD symptom severity to the effects observed with placebo treatment. Data were analyzed using multilevel analyses. We observed significant non-specific effects of methylphenidate for parent-rated ADHD symptoms, but not for teacher-rated symptoms. For parent reported hyperactive/impulsive symptoms, higher baseline symptoms predicted larger effects with placebo, indicating regression to the mean effects. For parent-reports, a significant part of the overall effect of methylphenidate treatment is explained by non-specific effects. Our findings stress the importance of taking non-specific effects into account when evaluating methylphenidate treatment, by including teacher-reports and using a double baseline assessment during titration. Comparing active medication with a placebo in the titration trial has the potential to identify non-specific effects.

A systematic review and meta-analysis of the placebo effect on both semen quality and male infertility

INTRODUCTION

Placebo influence on such objective indicators, as sperm quality and infertility, has not been studied previously, but some studies report that placebo may distort even objective outcomes. The aim of current study is to assess the placebo effect on fertility in patients suffering from sperm abnormalities and/or infertility.

EVIDENCE ACQUISITION

We conducted a search of two databases (Scopus and MEDLINE) and identified placebo-controlled clinical trials which focused on sperm abnormalities and/or male infertility treatment. Primary outcomes included changes in semen parameters (volume, total count, sperm concentration in semen, progressive motility, morphology (normal cells)). Secondary outcomes included DNA fragmentation and change in pregnancy rate.

EVIDENCE SYNTHESIS

Seventy-seven articles published from 1983 to 2022 were included. Statistically significant changes were observed for the following values: total sperm count, mean change 0.16 (95% CI 0.05, 0.26); P=0.004, I2=75.1%; and progressive motility, mean change 0.13 (95% CI 0.02, 0.24); P=0.026, I2=84.9%. In contrast, placebo did not affect sperm concentration, sperm volume, sperm morphology or DNA fragmentation index. The publication bias for all the values measured with Egger's test and funnel plots was low.

CONCLUSIONS

The current meta-analysis indicated a statistically significant increase of total sperm count and progressive motility in the placebo group. In contrast, placebo did not affect sperm concentration, sperm volume, sperm morphology and DNA fragmentation index. These findings should be considered while planning or analyzing placebo-controlled clinical trials.

Identification of group differences in predictive anticipatory biasing of pain during uncertainty: preparing for the worst but hoping for the best

ABSTRACT

Pain anticipation during conditions of uncertainty can unveil intrinsic biases, and understanding these biases can guide pain treatment interventions. This study used machine learning and functional magnetic resonance imaging to predict anticipatory responses in a pain anticipation experiment. One hundred forty-seven participants that included healthy controls (n = 57) and individuals with current and/or past mental health diagnosis (n = 90) received cues indicating upcoming pain stimuli: 2 cues predicted high and low temperatures, while a third cue introduced uncertainty. Accurate differentiation of neural patterns associated with specific anticipatory conditions was observed, involving activation in the anterior short gyrus of the insula and the nucleus accumbens. Three distinct response profiles emerged: subjects with a negative bias towards high pain anticipation, those with a positive bias towards low pain anticipation, and individuals whose predictions during uncertainty were unbiased. These profiles remained stable over one year, were consistent across diagnosed psychopathologies, and correlated with cognitive coping styles and underlying insula anatomy. The findings suggest that individualized and stable pain anticipation occurs in uncertain conditions.

Preserving the placebo effect after disclosure: A new perspective on non-deceptive placebos

The present study explores whether a particular style of placebo disclosure could serve as a tool to foster a renewed trust in one's own inherent resources and elicit a meaningful placebo effect. In a motor performance task, two placebo groups received inert transcutaneous electrical nerve stimulation (TENS) in each of four sessions along with information on its force-enhancing properties. Before the final session, one of the placebo groups was informed about the placebo, which was portrayed as a means to unleash an inherent potential. Along with force, we systematically monitored task-specific self-efficacy to test whether this variable would be differentially modulated in the two placebo groups. Compared to two control groups, placebo groups showed higher force and self-efficacy in the last session. No differences in self-efficacy were observed in the placebo groups even after revealing the placebo procedure, suggesting that the disclosure was effective in 'safeguarding' individuals' self-efficacy. These findings may have important implications, paving the way for the use of placebos that not only are ethically permissible but also support individuals' self-efficacy.

Placebo treatment affects brain systems related to affective and cognitive processes, but not nociceptive pain

Drug treatments for pain often do not outperform placebo, and a better understanding of placebo mechanisms is needed to improve treatment development and clinical practice. In a large-scale fMRI study (N = 392) with pre-registered analyses, we tested whether placebo analgesic treatment modulates nociceptive processes, and whether its effects generalize from conditioned to unconditioned pain modalities. Placebo treatment caused robust analgesia in conditioned thermal pain that generalized to unconditioned mechanical pain. However, placebo did not decrease pain-related fMRI activity in brain measures linked to nociceptive pain, including the Neurologic Pain Signature (NPS) and spinothalamic pathway regions, with strong support for null effects in Bayes Factor analyses. In addition, surprisingly, placebo increased activity in some spinothalamic regions for unconditioned mechanical pain. In contrast, placebo reduced activity in a neuromarker associated with higher-level contributions to pain, the Stimulus Intensity Independent Pain Signature (SIIPS), and affected activity in brain regions related to motivation and value, in both pain modalities. Individual differences in behavioral analgesia were correlated with neural changes in both modalities. Our results indicate that cognitive and affective processes primarily drive placebo analgesia, and show the potential of neuromarkers for separating treatment influences on nociception from influences on evaluative processes.

Personal belief on elastic tape and tape tension affect perceived performance, but not muscle activity and endurance

BACKGROUND

Previous studies reported inconsistent outcomes on elastic taping for three potential reasons: 1) poor control of placebo effect; 2) no consensus regarding the optimal tape tension; and 3) lack of investigation on muscle endurance, as the proposed tape recoiling force may not promote peak force generation but exert a consistently low force and improve submaximal contraction.

PURPOSE

This study compared the effects of elastic tape and its tension on muscle activity and endurance in people with extremely positive and negative personal belief on elastic tape.

METHODS

Using a validated instrument, we identified 20 participants with extremely positive personal belief on elastic tape (+ belief), and 20 with extremely negative personal belief (- belief). They performed wrist isometric endurance tests under three taping conditions (i.e. no tape, 50%, and 100% tension). We measured isometric wrist extensor muscle endurance, electromyography muscle activity, and self-perceived performance for each condition.

RESULTS

The differences between the two groups in isometric muscle endurance (p = .85) and muscle activity (p = .53) were not statistically significant, regardless of tape conditions. However, participants with + belief reported better perceived performance than those with - belief (p < .001, partial eta squared = 0.70). Specifically, 100% tape tension yielded stronger self-perceived performance than 50% tension (Cohen's d = 0.91) and no tape (Cohen's d = 1.86). On the other hand, participants with - belief perceived similar performance across tape tensions (p = .55).

CONCLUSION

Elastic tape does not modulate muscle activity and enhance muscle endurance. People with a strong positive personal belief on elastic tape may perceive a better performance with a greater tape tension.

Placebo and Nocebo Effects on Sports and Exercise Performance: A Systematic Literature Review Update

Sports performance could be affected by placebo and nocebo effects. The last literature review on placebo and nocebo effects on sports and exercise performance was published in 2019. In the past five years, several new studies have been published. This review aimed to update the previous synthesis and evaluate the results of new studies focusing on placebo or nocebo interventions in sports and exercise by determining the form and magnitude of their effect. Hence, we searched for empirical studies published from 2019 until the end of May 2024 indexed in PubMed, Medline, Web of Science, EBSCO, and Google Scholar databases. The search yielded 20 eligible studies with control or baseline-control conditions, focusing on nutritional, mechanical, and other mixed ergogenic aids. They yielded small to large placebo effects (Cohen's d) for nutritional (d = 0.86), mechanical (d = 0.38), cream and gel (d = 0.05), and open-label placebo (d = 0.16) interventions. The pooled effect size for placebo effects was moderate to large (d = 0.67), larger than in the earlier review, suggesting that placebo effects can improve motor performance even more than previously reported. However, based on five measures from three studies, the nocebo effects were almost twice as large (d = 1.20). Accordingly, the current findings support and expand the last review in the field by yielding additional support for placebo and nocebo effects in sports and exercise.

Placebo effects of repetitive transcranial magnetic stimulation on negative symptoms and cognition in patients with schizophrenia spectrum disorders: a systematic review and meta-analysis

Background

Negative symptoms and cognitive impairments are highly frequent in schizophrenia spectrum disorders (SSD), associated with adverse functional outcomes and quality of life. Repetitive transcranial magnetic stimulation (rTMS) has been considered a promising therapeutic option in SSD. However, placebo effects of rTMS on these symptoms remained unclear.

Objective

To investigate placebo effects of rTMS on alleviating negative symptoms and cognitive impairment in patients with SSD and to explore potential moderators.

Methods

We systematically searched five electronic databases up to 15 July 2023. Randomized, double-blind, sham-controlled trials investigating effects of rTMS on negative symptoms or cognition in patients with SSD were included. The pooled placebo effect sizes, represented by Hedges' g, were estimated using the random-effects model. Potential moderators were explored through subgroup analysis and meta-regression.

Results

Forty-four randomized controlled trials with 961 patients (mean age 37.53 years; 28.1% female) in the sham group were included. Significant low-to-moderate pooled placebo effect sizes were observed for negative symptoms (g=0.44, p<0.001), memory (g=0.31, p=0.010), executive function (g=0.35, p<0.001), working memory (g=0.26, p=0.004), and processing speed (g=0.36, p=0.004). Subgroup analysis indicated that placebo effects were affected by sham stimulation methods, rTMS targeting approaches, and stimulation frequency.

Conclusions

Placebo effects of rTMS on negative symptoms and cognition in patients with SSD are significant in a small-to-moderate magnitude, which might be mediated by rTMS parameters. Our findings will provide new insights for practitioners to further optimize and establish standardized rTMS protocols for future RCTs tackling cardinal symptoms in SSD.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42023390138.

Cross-sectional study of psychiatric disorders in patients with chronic musculoskeletal pain and individuals without pain

BACKGROUND

Musculoskeletal chronic pain is a leading cause of global disability and laboral incapacity. However, there is a lack of population-based studies that investigate the relationship between chronic pain and mental disorders with a control group, particularly among low- and middle-income countries. Chronic pain is a serious public health problem in terms of human suffering, and in terms of socioeconomic implications. Frequent association with different mental disorders increases disability, decreases quality of life, and makes diagnosis and treatment challenging. The present study aimed to evaluate the presence of mental disorders in patients with chronic musculoskeletal pain and compare with a control group without pain.

METHODS

We selected 100 patients in a regular follow-up at the Musculoskeletal Pain Outpatient Clinic of the University Hospital and compared them with 100 painless individuals from the control group from June 2016 to June 2018. The instruments used were the Mini International Neuropsychiatric Interview (MINI-PLUS) and a structured questionnaire to collect sociodemographic data. Statistical analysis used t-test, chi-square, Fisher's exact test, Mann-Whitney, Kolmogorov-Smirnov tests, and multiple logistic regression.

RESULTS

In the sample evaluated, the majority of patients were women (83%), of brown color (54%), with lower-level education (51%), lower salary range (73%) and high absenteeism rate at work (60,7%). Patients with chronic pain had more psychiatric disorders (88% vs. 48% in the control group; p < 0.001). The most frequent diagnoses were anxiety disorders with panic attacks (44%), generalized anxiety (36%), mixed anxiety and depression disorder (33%), social phobia (30%), agoraphobia (29%), suicide risk (28%), and major depression (27%).

CONCLUSION

Positive correlations of mental disorders and chronic musculoskeletal pain have been documented. This suggests that psychiatric components must be taken into account in the management of chronic pain syndromes. The use of Mini Plus as a diagnostic tool for psychiatric disorders can contribute to optimizing the diagnosis and treatment of patients with chronic pain and encourage the creation of policies with strategies and criteria for quick access to Multi-professional Services.

Written Imaginal Exposure for Hoarding Disorder: A Preliminary Pilot Study

ABSTRACT

Hoarding disorder (HD) is marked by difficulty discarding possessions. Many refuse treatment or drop out, which may be due to treatment's incorporation of in-home decluttering, which is feared and avoided. Thus, strategies to prepare patients for decluttering/discarding are needed. Imaginal exposure (IE), or imagining one's worst fears about discarding, could be one such strategy. This pilot preliminarily tested a short-duration IE intervention compared with a control intervention. Over 3 days, adults diagnosed with HD (n = 32) were randomly assigned to either write about and imagine their worst fears about discarding (IE condition) or a neutral topic (control writing [CW] condition). The IE condition showed significant improvements in HD symptoms from preintervention to 1-week follow-up, with medium to large effects; however, the CW condition did as well. Comparing change scores between conditions, the IE condition's improvements were not significantly different than the CW condition's. Overall, IE was helpful in improving HD symptoms, but this pilot did not indicate that it was more helpful than CW. This raises important questions about possible demand characteristics, placebo effects, or regression to the mean, and it has implications for the design and methodology of other studies assessing IE's utility.

Practitioner warmth and empathy attenuates the nocebo effect and enhances the placebo effect

Augmented patient-practitioner interactions that enhance therapeutic alliance can increase the placebo effect to sham treatment. Little is known, however, about the effect of these interactions on maladaptive health outcomes (i.e., the nocebo effect). Healthy participants (N = 84) were randomised to a 3-day course of Oxytocin nasal drops (actually, sham treatment) in conjunction with a high-warmth interaction (Oxy-HW: N = 28), a low-warmth interaction (Oxy-LW: N = 28) or to a no treatment control group (NT: N = 28). All participants were informed that the Oxytocin treatment could increase psychological well-being but was associated with several potential side effects. Treatment-related side effects, unwarned symptoms, and psychological well-being were measured at baseline and all post-treatment days. Side effect reporting was increased in the Oxy-LW condition compared to the other groups across all days. Conversely, increased psychological well-being was observed in the Oxy-HW condition, relative to the other conditions, but only on Day 1. Among those receiving treatment, positive and negative expectations, and treatment-related worry, did not vary by interaction-style, while psychological well-being and side effect reporting were inversely associated at the level of the individual. Results have important implications for practice, suggesting poorer quality interactions may not only reduce beneficial health outcomes but also exacerbate those that are maladaptive.

Boosting open-label placebo effects in acute induced pain in healthy adults (BOLPAP-study): study protocol of a randomized controlled trial

Introduction

Pain is a highly prevalent symptom in the hospital setting, but treatment options remain limited. Harnessing the placebo effect in an ethical manner could provide a new possibility to reduce pain in clinical practice. So called open-label placebos (OLP) have been shown to elicit significant effects in reducing acute pain. But, before implementation, more knowledge concerning the properties of OLPs is needed. This study aims to assess the duration of analgesic effects from OLP and to determine the possibility of boosting such effects.

Methods and analysis

This is the protocol of an ongoing (first patient enrolled in March 2023) single-site randomized trial investigating OLPs in two parts (i.e., substudies). In both parts, pain will be induced in healthy adults using an intradermal electrical stimulation model. Participants in Part 1 will have two study visits: An interventional visit with one OLP injection accompanied by an evidence-based treatment rationale and a control visit with no treatment. For Part 2, participants will be randomized into three groups: (1) A fixed-time "Booster" group including one single repetition of the OLP injection at a fixed time point, (2) an on-demand "Booster" group including one single repetition of the OLP injection on-demand, and (3) a control group who will receive just one OLP injection. Differences in pain ratings over time (using the Numeric Rating Scale) will be analyzed with several two-sample t-tests. The time point for a fixed-time "Booster" in Part 2 will be derived from Part 1 with additional statistical tools such as a broken-stick mixed-effect model.

Discussion

This study aims to further characterize the analgesic effects of OLPs. In doing so, it will provide valuable information needed for later implementation of OLPs in clinical practice, where they could play a role in multimodal analgesic concepts.

Ethics and dissemination

The "Ethikkommission Nordwest- und Zentralschweiz" (BASEC 2023-00296) approved the study protocol. Results of the analysis will be submitted for publication in a peer-reviewed journal.

Clinical Trial Registration

This study is registered at ClinicalTrials.gov (NCT05819476) and is listed in the Swiss National Registry at kofam.ch (SNCTP000005470).

Nicotine-related beliefs induce dose-dependent responses in the human brain

Beliefs have a powerful influence on our behavior, yet their neural mechanisms remain elusive. Here we investigate whether beliefs could impact brain activities in a way akin to pharmacological dose-dependent effects. Nicotine-dependent humans were told that nicotine strength in an electronic cigarette was either 'low', 'medium' or 'high', while nicotine content was held constant. After vaping, participants underwent functional neuroimaging and performed a decision-making task known to engage neural circuits affected by nicotine. Beliefs about nicotine strength induced dose-dependent responses in the thalamus, a key binding site for nicotine, but not in other brain regions such as the striatum. Nicotine-related beliefs also parametrically modulated the connectivity between the thalamus and ventromedial prefrontal cortex, a region important for decision-making. These findings reveal a high level of precision in the way beliefs influence the brain, offering mechanistic insights into humans' heterogeneous responses to drugs and a pivotal role of beliefs in addiction.

The difference in all-cause mortality between COVID-19 patients treated with standard of care plus placebo and those treated with standard of care alone: a network meta-analysis of randomised controlled trials of immunomodulatory kinase inhibitors

OBJECTIVES

The aim of this network meta-analysis (NMA) was to assess whether participants assigned to a placebo and standard of care (SoC) group had different major coronavirus disease 2019 (COVID-19)-related outcomes than those assigned to SoC alone.

DESIGN

Frequentist model-based NMA.

SETTING

We searched for randomised controlled trials (RCTs) of Janus kinase/Bruton tyrosine kinase inhibitors for the management of COVID-19.

PARTICIPANTS

Patients with COVID-19 infection.

MAIN OUTCOME MEASURES

The primary outcome was the 28-day all-cause mortality, and secondary outcomes were: (1) use of mechanical ventilation; (2) secondary bacterial infection; (3) acceptability (i.e. drop-out rate); and (4) safety (i.e. serious adverse events). We conducted an NMA using the frequentist model. Effect sizes were estimated using odds ratios (ORs) with 95% confidence intervals (95% CIs).

RESULTS

We identified 14 eligible RCTs enrolling a total of 13,568 participants with COVID-19. Participants assigned to placebo plus SoC had a significantly higher risk of 28-day all-cause mortality than those receiving SoC alone (OR = 1.39, 95% CI = 1.07-1.79). This finding did not change substantially by subgroup analysis stratified by epidemiology factor, pandemic history progression and statistical methodologic consideration. In addition, none of the treatments investigated were associated with a significantly different risk of secondary bacterial infection, acceptability or safety compared with the SoC group.

CONCLUSIONS

This NMA suggested a higher all-cause mortality in patients treated with placebo plus SoC compared with those treated with SoC alone. However, caution is advised in interpreting these results due to the absence of a direct head-to-head comparison. Future research should critically evaluate the necessity of placebo administration in COVID-19 RCTs and consider alternative study designs to minimise potential biases.Trial registration: The current study was approved by the Institutional Review Board of the Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan (TSGHIRB No. B-109-29) and registered in PROSPERO (CRD42022376217).

Can Pharmacological Conditioning as an Add-On Treatment Optimize Standard Pharmacological Treatment in Patients with Recent-Onset Rheumatoid Arthritis? A Proof-of-Principle Randomized Clinical Trial

Medication regimens using conditioning via variable reinforcement have shown similar or improved therapeutic effects as full pharmacological treatment, but evidence in patient populations is scarce. This proof-of-principle double-blind randomized clinical trial examined whether treatment effects in recent-onset rheumatoid arthritis (RA) can be optimized through pharmacological conditioning. After four months of standardized treatment (n = 46), patients in clinical remission (n = 19) were randomized to the Control group (C), continuing standardized treatment (n = 8), or the Pharmacological Conditioning (PC) group, receiving variable treatment according to conditioning principles (n = 11). After eight months, treatment was tapered and discontinued linearly (C) or variably (PC). Standard treatment led to large improvements in disease activity and HRQoL in both groups. The groups did not differ in the percentage of drug-free clinical remission obtained after conditioning or continued standard treatment. The PC group did show a larger decrease in self-reported disease activity (Cohen's d = 0.9) and a smaller increase in TNF-α levels (Cohen's d = 0.7) than the C group. During all phases, more differences between groups were found for the patients who followed protocol than for the intention-to-treat sample. Although the results are not conclusive, pharmacological conditioning may have some advantages in terms of disease progression and stability, especially during the conditioning phase, compared with standard clinical treatment. The effects may be particularly beneficial for patients who show a good initial response to increased medication dosages.

Mapping expectancy-based appetitive placebo effects onto the brain in women

Suggestions about hunger can generate placebo effects on hunger experiences. But, the underlying neurocognitive mechanisms are unknown. Here, we show in 255 women that hunger expectancies, induced by suggestion-based placebo interventions, determine hunger sensations and economic food choices. Functional magnetic resonance imaging in a subgroup (n = 57/255) provides evidence that the strength of expecting the placebo to decrease hunger moderates medial prefrontal cortex activation at the time of food choice and attenuates ventromedial prefrontal cortex (vmPFC) responses to food value. Dorsolateral prefrontal cortex activation linked to interference resolution formally mediates the suggestion-based placebo effects on hunger. A drift-diffusion model characterizes this effect by showing that the hunger suggestions bias participants' food choices and how much they weigh tastiness against the healthiness of food, which further moderates vmPFC-dlPFC psychophysiological interactions when participants expect decreased hunger. Thus, suggestion-induced beliefs about hunger shape hunger addressing economic choices through cognitive regulation of value computation within the prefrontal cortex.

The Placebo Effect in Exercise and Mental Health Research

This chapter describes the placebo effect in the context of physical activity and mental health. Following a brief historical overview, definitions for placebos, placebo effects, and related terminology are discussed. Next, three major methodological challenges posed from studying the placebo effect in the context of exercise are described. Additionally, the role of a primary psychological mechanism of placebo and nocebo effects - expectations - will be summarized through the lens of key terminology. Findings from relevant chronic and acute exercise studies that have measured or manipulated exercise-associated expectations will be presented. The chapter concludes with recommendations for controlling or quantifying the placebo effect in exercise and mental health research and its implications in clinical practice.

Chewing performance of patients with worn dentition before and after restorations: A scoping review

BACKGROUND

Tooth wear is a multifactorial complex process related to the loss of dental tissue, due to chemical or mechanical processes, by abrasion, attrition, erosion. Restorative treatment represents an attempt to rebuild and recreate the lost structure.

OBJECTIVE

This scoping review aims to investigate whether restorative treatment of worn dentition (either with direct or indirect adhesive composite adhesive procedures or with prosthetic techniques) can have an impact on the masticatory performance parameters.

METHODS

A scoping review was conducted on multiple databases (Pubmed, Medline CENTRAL, ICTRP), following the PRISMA guidelines. Abstracts of research papers were screened for suitability, and full-text articles were obtained for those who satisfied the inclusion and exclusion criteria.

RESULTS

Only one article meet the inclusion criteria of the review. Restorative treatment of worn dentition although have a positive impact on the self-report ability to chew, has no effect on the masticatory performance test.

CONCLUSION

At the moment, not enough evidence to comment on the actual therapeutic role of restorative treatment on tooth wear is available. Clinicians, before taking any clinical decision, should carefully discuss with patients the needs and expectations of the treatment plan.

Communication, Cognition and Competency Development in Healthcare: A Model for Integrating Cognitive Ethnography and Communication Skills Training in Clinical Interventions

OBJECTIVES

The aim of this study was to conduct and evaluate the Blended Learning communication skills training program. The key objective was to investigate (i) how clinical intervention studies can be designed to include cognitive, organizational, and interactive processes, and (ii) how researchers and practitioners could work with integrated methods to support the desired change.

METHODS

The method combined design and implementation of a 12-week Blended Learning communication skills training program based on the Calgary-Cambridge Guide. The training was implemented in a patient clinic at a Danish university hospital and targeted all healthcare professionals at the clinic. Cognitive ethnography was used to document and evaluate healthcare professionals' implementation and individual competency development, and support the design of in-situ simulation training scenarios.

RESULTS

Thirteen participants completed the program. The synergy within the teams, as well as the opportunities for participants to coordinate, share, discuss, and reflect on the received knowledge with a colleague or on-site researcher, affected learning positively. The knowledge transfer process was affected by negative feedback loops, such as time shortages, issues with concept development and transfer, disjuncture between the expectations of participants and instructors of the overall course structure, as well as participant insecurity and a gradual loss of motivation and compliance.

CONCLUSION

We propose a novel 3-step model for clinical interventions based on our findings and literature review. This model will effectively support the implementation of educational interventions in health care by narrowing the theory-practice gap. It will also stimulate desired change in individual behavior and organizational culture over time. Furthermore, it will work for the benefit of the clinic and may be more suitable for the implementation of communication projects than, for example, randomized setups.

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

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

Existence of Quantum Pharmacology in Sartans: Evidence in Isolated Rabbit Iliac Arteries

Quantum pharmacology introduces theoretical models to describe the possibility of ultra-high dilutions to produce biological effects, which may help to explain the placebo effect observed in hypertensive clinical trials. To determine this within physiology and to evaluate novel ARBs, we tested the ability of known angiotensin II receptor blockers (ARBs) (candesartan and telmisartan) used to treat hypertension and other cardiovascular diseases, as well as novel ARBs (benzimidazole-N-biphenyl tetrazole (ACC519T), benzimidazole-bis-N,N'-biphenyl tetrazole (ACC519T(2)) and 4-butyl-N,N0-bis[[20-2Htetrazol-5-yl)biphenyl-4-yl]methyl)imidazolium bromide (BV6(K+)2), and nirmatrelvir (the active ingredient in Paxlovid) to modulate vascular contraction in iliac rings from healthy male New Zealand White rabbits in responses to various vasopressors (angiotensin A, angiotensin II and phenylephrine). Additionally, the hemodynamic effect of ACC519T and telmisartan on mean arterial pressure in conscious rabbits was determined, while the ex vivo ability of BV6(K+)2 to activate angiotensin-converting enzyme-2 (ACE2) was also investigated. We show that commercially available and novel ARBs can modulate contraction responses at ultra-high dilutions to different vasopressors. ACC519T produced a dose-dependent reduction in rabbit mean arterial pressure while BV6(K+)2 significantly increased ACE2 metabolism. The ability of ARBs to inhibit contraction responses even at ultra-low concentrations provides evidence of the existence of quantum pharmacology. Furthermore, the ability of ACC519T and BV6(K+)2 to modulate blood pressure and ACE2 activity, respectively, indicates their therapeutic potential against hypertension.

Drug-Free Noninvasive Thermal Nerve Block: Validation of Sham Devices

Headache is a leading cause of disability and suffering. One major challenge in developing device treatments is demonstrating their efficacy given devices' often-high placebo rate. This paper reviews the importance of validating sham devices as part of finalizing the design for larger-scale prospective randomized controlled trials in patients with chronic headache as well as the results of a prospective, single-blind trial to validate two potential sham noninvasive thermal nerve block devices. Study participants were trained to self-administer thermal nerve block treatment using sham devices in an office visit. Two different sham systems with different temperature profiles were assessed. Devices were offered for patients to use daily at-home for one week to assess the durability of sham placebo effects before participants were given active treatment in a second office visit followed by another optional week of self-administered active treatment at-home use. Sham treatments reduced pain scores by an average of 31% from 6.0 ± 2.3 to 4.3 ± 3.3, including two participants who fell asleep during the in-office treatment and woke up with no pain, but whose pain recurred after returning home during at-home use of the sham system. In-office active treatments reduced pain scores by 52% from 6.7 ± 2.1 to 3.3 ± 2.9 with sustained pain relief during optional at-home use. Successful blinding for the study was confirmed with an ideal Bang's Blinding Index of 0 and an ideal James' Blinding Index of 1. Both the sham and active treatments were viewed by participants as highly credible, and credibility increased from the beginning to end of sham treatments on average.

Impact of Low-Dose Dronabinol Therapy on Cognitive Function in Cancer Patients Receiving Palliative Care: A Case-Series Intervention Study

Background

Cannabis may offer therapeutic benefits to patients with advanced cancer not responding adequately to conventional palliative treatment. However, tolerability is a major concern. Cognitive function is a potential adverse reaction to tetrahydrocannabinol containing regimens. The aim of this study was to test cognitive function in patients being prescribed dronabinol as an adjuvant palliative therapy.

Methods

Adult patients with advanced cancer and severe related pain refractory to conventional palliative treatment were included in this case-series study. Patients were examined at baseline in conjunction with initiation of dronabinol therapy and at a two-week follow-up using three selected Wechsler's adult intelligence scale III neurocognitive tests: Processing Speed Index (PSI), Perceptual Organization Index (POI), and Working Memory Index (WMI). Patients were also assessed using pain visual analog scale, Major Depression Inventory, and Brief Fatigue Inventory.

Results

Eight patients consented to take part in the study. Two patients discontinued dronabinol therapy, one due to a complaint of dizziness and another critical progression of cancer disease, respectively. The remaining six patients were successfully treated with a daily dosage of 12.5 mg dronabinol (p = 0.039). PSI (p = 0.020), POI (p = 0.034.), and WMI (p = 0.039).

Conclusions

Cognitive function improved in this group of patients with advanced cancer in conjunction with low-dose dronabinol therapy. The cause is likely multifactorial including reported relief of cancer-associated symptoms. Further clinical investigation is required.

Chronic fatigue syndromes: real illnesses that people can recover from

The 'Oslo Chronic Fatigue Consortium' consists of researchers and clinicians who question the current narrative that chronic fatigue syndromes, including post-covid conditions, are incurable diseases. Instead, we propose an alternative view, based on research, which offers more hope to patients. Whilst we regard the symptoms of these conditions as real, we propose that they are more likely to reflect the brain's response to a range of biological, psychological, and social factors, rather than a specific disease process. Possible causes include persistent activation of the neurobiological stress response, accompanied by associated changes in immunological, hormonal, cognitive and behavioural domains. We further propose that the symptoms are more likely to persist if they are perceived as threatening, and all activities that are perceived to worsen them are avoided. We also question the idea that the best way to cope with the illness is by prolonged rest, social isolation, and sensory deprivation.Instead, we propose that recovery is often possible if patients are helped to adopt a less threatening understanding of their symptoms and are supported in a gradual return to normal activities. Finally, we call for a much more open and constructive dialogue about these conditions. This dialogue should include a wider range of views, including those of patients who have recovered from them.

Placebo effects on all-cause mortality of patients with COVID-19 in randomized controlled trials of interleukin 6 antagonists: A systematic review and network meta-analysis

AIM

Many randomized controlled trials (RCTs) have investigated the use of interleukin 6 antagonists for the treatment of coronavirus disease 2019 (COVID-19), yielding inconsistent results. This network meta-analysis (NMA) aimed to identify the source of these inconsistent results by reassessing whether participants treated with standard of care (SoC) plus placebo have different all-cause mortality from those treated with SoC alone and to reevaluate the efficacy of interleukin 6 antagonists in the treatment of COVID-19.

METHODS

We conducted a systematic search for relevant RCTs from the inception of electronic databases through 1 September 2022. The primary outcome was all-cause mortality. The secondary outcomes were the incidences of major medical events, secondary infections, all-cause discontinuation, and serious adverse events.

RESULTS

The results of NMA of 33 RCTs showed that patients with COVID-19 treated with SoC plus placebo had lower odds of all-cause mortality than those who received SoC alone (OR, 0.75 [95% confidence interval, 0.58-0.97]). This finding remained consistent after excluding studies with no incident deaths. In addition, when we consider the impact of the widely promoted COVID-19 vaccination and newly developed antiviral treatment strategy, the results from the analysis of the RCT published in 2021 and 2022 remained similar.

CONCLUSION

These findings suggest the potential influence of placebo effects on the treatment outcomes of COVID-19 in RCTs. When evaluating the efficacy of treatment strategies for COVID-19, it is crucial to consider the use of placebo in the design of clinical trials.

The Fragility of Statistical Significance in Sham Orthopaedic Surgery: A Systematic Review of Randomized Controlled Trials

OBJECTIVES

The purpose of this study was to determine the stability of statistical findings among sham surgery randomized controlled trials (RCTs) in orthopaedic surgery using fragility analysis.

METHODS

PubMed systematic review was conducted to include studies reporting dichotomous outcomes pertaining to sham surgery. The final review included eight RCTs involving only partial meniscectomies and vertebroplasties from 2009 to 2020. With a fixed sample size with dichotomous outcome measures (events versus non-events), the Total Fragility Index (TFI), which is composed of the fragility index (FI) and reverse fragility index (RFI), was calculated by altering the ratio of events to non-events in an iterative fashion until results were reversed from significant to nonsignificant findings (FI) or vice versa (RFI). The TFI, FI, and RFI were divided by their sample sizes to obtain the respective total fragility quotient, fragility quotient (FQ), and reverse fragility quotient. Median fragility indices and quotients were reported for all studies.

RESULTS

The eight RCTs included 50 dichotomous outcomes involving either partial meniscectomies or vertebroplasties, with a median TFI and total fragility quotient of 5 [interquartile range (IQR) 4 to 6] and 0.035 (IQR 0.028 to 0.048), respectively, indicating that a median of five total patients or 3.5 per 100 patients would need to experience a different outcome to reverse significant or insignificant findings for each of the eight trials. Among the 8 statistically significant ( P < 0.05) outcome events (16%), the respective FI and FQ were 2 (IQR 1 to 5) and 0.018 (IQR 0.010 to 0.044). Among the 42 statistically insignificant outcome events (84%), the respective RFI and reverse fragility quotient were 5 (IQR 4 to 6) and 0.04 (IQR 0.034 to 0.048). The median number of patients lost to follow-up was 1.5 (IQR 0.5 to 2).

CONCLUSION

The unstable findings in partial meniscectomy and vertebroplasty sham surgical RCTs undermine their study conclusions and recommendations. We recommend using fragility analysis in future sham surgical RCTs to contextualize statistical findings.

LEVEL OF EVIDENCE

Level IV; Systematic Review.

Toward Parsimony in Bias Research: A Proposed Common Framework of Belief-Consistent Information Processing for a Set of Biases

One of the essential insights from psychological research is that people's information processing is often biased. By now, a number of different biases have been identified and empirically demonstrated. Unfortunately, however, these biases have often been examined in separate lines of research, thereby precluding the recognition of shared principles. Here we argue that several-so far mostly unrelated-biases (e.g., bias blind spot, hostile media bias, egocentric/ethnocentric bias, outcome bias) can be traced back to the combination of a fundamental prior belief and humans' tendency toward belief-consistent information processing. What varies between different biases is essentially the specific belief that guides information processing. More importantly, we propose that different biases even share the same underlying belief and differ only in the specific outcome of information processing that is assessed (i.e., the dependent variable), thus tapping into different manifestations of the same latent information processing. In other words, we propose for discussion a model that suffices to explain several different biases. We thereby suggest a more parsimonious approach compared with current theoretical explanations of these biases. We also generate novel hypotheses that follow directly from the integrative nature of our perspective.

How Do Expectations Modulate Pain? A Motivational Perspective

Expectations can profoundly modulate pain experience, during which the periaqueductal gray (PAG) plays a pivotal role. In this article, we focus on motivationally evoked neural activations in cortical and brainstem regions both before and during stimulus administration, as has been demonstrated by experimental studies on pain-modulatory effects of expectations, in the hope of unraveling how the PAG is involved in descending and ascending nociceptive processes. This motivational perspective on expectancy effects on the perception of noxious stimuli sheds new light on psychological and neuronal substrates of pain and its modulation, thus having important research and clinical implications.

A systematic review and activation likelihood estimation meta-analysis of fMRI studies on arousing or wake-promoting effects in Buddhist meditation

Conventional Buddhist texts illustrate meditation as a condition of relaxed alertness that must fend against extreme hypoarousal (sleep, drowsiness) and extreme hyperarousal (restlessness). Theoretical, neurophysiological, and neuroimaging investigations of meditation have highlighted the relaxing effects and hypoarousing without emphasizing the alertness-promoting effects. Here we performed a systematic review supported by an activation-likelihood estimate (ALE) meta-analysis in an effort to counterbalance the surfeit of scholarship emphasizing the hypoarousing and relaxing effects of different forms of Buddhist meditation. Specifically, the current systematic review-cum-meta-analytical review seeks to highlight more support for meditation's wake-promoting effects by drawing from neuroimaging research during wakefulness and meditation. In this systematic review and meta-analysis of 22 fMRI studies, we aim to highlight support for Buddhist meditation's wake-promoting or arousing effects by identifying brain regions associated with alertness during meditation. The most significant peaks were localized medial frontal gyrus (MFG) and precuneus. We failed to determine areas ostensibly common to alertness-related meditation such as the medial prefrontal cortex (mPFC), superior parietal lobule, basal ganglia, thalamus, most likely due to the relatively fewer fMRI investigations that used wakefulness-promoting meditation techniques. Also, we argue that forthcoming research on meditation, related to alertness or wakefulness, continues to adopt a multi-modal method to investigate the correlation between actual behaviors and neural networks connected to Buddhist meditation. Moreover, we recommend the implementation of fMRI paradigms on Buddhist meditation with clinically diagnosed participants to complement recent trends in psychotherapy such as mindfulness-based cognitive therapy (MBCT).

Probiotic responder identification in cross-over trials for constipation using a Bayesian statistical model considering lags between intake and effect periods

Recent advances in microbiome research have led to the further development of microbial interventions, such as probiotics and prebiotics, which are potential treatments for constipation. However, the effects of probiotics vary from person to person; therefore, the effectiveness of probiotics needs to be verified for each individual. Individuals showing significant effects of the target probiotic are called responders. A statistical model for the evaluation of responders was proposed in a previous study. However, the previous model does not consider the lag between intake and effect periods of the probiotic. It is expected that the lag exists when probiotics are administered and when they are effective. In this study, we propose a Bayesian statistical model to estimate the probability that a subject is a responder, by considering the lag between intake and effect periods. In synthetic dataset experiments, the proposed model was found to outperform the base model, which did not factor in the lag. Further, we found that the proposed model could distinguish responders showing large uncertainty in terms of the lag between intake and effect periods.

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.

Placebo treatment affects brain systems related to affective and cognitive processes, but not nociceptive pain

Placebo analgesia is a replicable and well-studied phenomenon, yet it remains unclear to what degree it includes modulation of nociceptive processes. Some studies find effects consistent with nociceptive effects, but meta-analyses show that these effects are often small. We analyzed placebo analgesia in a large fMRI study (N = 392), including placebo effects on brain responses to noxious stimuli. Placebo treatment caused robust analgesia in both conditioned thermal and unconditioned mechanical pain. Placebo did not decrease fMRI activity in nociceptive pain regions, including the Neurologic Pain Signature (NPS) and pre-registered spinothalamic pathway regions, with strong support from Bayes Factor analyses. However, placebo treatment affected activity in pre-registered analyses of a second neuromarker, the Stimulus Intensity Independent Pain Signature (SIIPS), and several associated a priori brain regions related to motivation and value, in both thermal and mechanical pain. Individual differences in behavioral analgesia were correlated with neural changes in both thermal and mechanical pain. Our results indicate that processes related to affective and cognitive aspects of pain primarily drive placebo analgesia.

Predictors of Clinical Remission to Placebo in Clinical Trials of Crohn's Disease

BACKGROUND

In placebo-controlled clinical trials for Crohn's disease (CD), some placebo-treated patients demonstrate improvement. However, it is unclear what factors contribute to placebo response and remission.

METHODS

This was a post hoc analysis of 3 placebo-controlled clinical trial programs (GEMINI-2, UNITI-1/2, and CLASSIC-1) of moderate-severe CD evaluating the efficacy of vedolizumab, ustekinumab, and adalimumab. Baseline predictors of clinical remission at the end of induction (week 4/6), defined as Crohn's Disease Activity Index <150 were evaluated among placebo-treated patients. Clinical response (decrease in Crohn's Disease Activity Index ≥100 points from baseline) at the end of induction was also evaluated. Univariate analyses were performed and predictors with P < .10 were included in multivariable analyses.

RESULTS

A total of 683 patients (148 from GEMINI-2, 470 from UNITI-1/2, and 65 from CLASSIC-1) treated with placebo were included. Of the predictors evaluated, C-reactive protein <5 mg/L (odds ratio [OR], 1.66; 95% confidence interval [CI], 1.04-2.67; P = .035), albumin >40 g/L (OR, 1.57; 95% CI, 1.05-2.93; P = .023), and disease duration <5 years (OR, 1.70; 95% CI, 1.05-2.75; P = .032) were included in the multivariable model for clinical remission. Disease duration <5 years was the only variable that retained significance on multivariable analysis (adjusted OR, 1.67; 95% CI, 1.02-2.73; P = .040). For clinical response, isolated ileal disease and disease duration <1 year were included in the multivariable model, of which only the latter retained significance (adjusted OR, 1.84; 95% CI, 1.04-3.24; P = .035).

CONCLUSIONS

Strategies that reduce placebo response rates in clinical trials of CD should be considered, including stratification or exclusion of subjects by disease duration and mild disease severity as measured by objective biomarkers.

Longitudinal Meta-Analysis of Historical Parkinson's Disease Trials to Inform Future Trial Design

BACKGROUND

The outcome of clinical trials in neurodegeneration can be highly uncertain due to the presence of a strong placebo effect.

OBJECTIVES

To develop a longitudinal model that can enhance the success of future Parkinson's disease trials by quantifying trial-to-trial variations in placebo and active treatment response.

METHODS

A longitudinal model-based meta-analysis was conducted on the total score of Unified Parkinson's Disease Rating Scale (UPDRS) Parts 1, 2, and 3. The analysis included aggregate data from 66 arms (observational [4], placebo [28], or investigational-drug-treated [34]) from 4 observational studies and 17 interventional trials. Inter-study variabilities in key parameters were estimated. Residual variability was weighted by the size of study arms.

RESULTS

The baseline total UPDRS was estimated to average at 24.5 points. Disease score was estimated to worsen by 3.90 points/year for the duration of the treatments; whilst notably, arms with a lower baseline progressed faster. The model captured the transient nature of the placebo response and sustained symptomatic drug effect. Both placebo and drug effects peaked within 2 months; although, 1 year was needed to observe the full treatment difference. Across these studies, the progression rate varied by 59.4%, the half-life for offset of placebo response varied by 79.4%, and the amplitude for drug effect varied by 105.3%.

CONCLUSION

The longitudinal model-based meta-analysis describes UPDRS progression rate, captures the dynamics of the placebo response, quantifies the effect size of the available therapies, and sets the expectation of uncertainty for future trials. The findings provide informative priors to enhance the rigor and success of future trials of promising agents, including potential disease modifiers. © 2023 GSK. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Cultural evolution from the producers' standpoint

Standard approaches to cultural evolution focus on the recipients or consumers. This does not take into account the fitness costs incurred in producing the behaviours or artefacts that become cultural, i.e. widespread in a social group. We argue that cultural evolution models should focus on these fitness costs and benefits of cultural production, particularly in the domain of 'symbolic' culture. In this approach, cultural products can be considered as a part of the extended phenotype of producers, which can affect the fitness of recipients in a positive way (through cooperation) but also in a detrimental way (through manipulation and exploitation). Taking the producers' perspective may help explain the specific features of many kinds of cultural products.