A Positive Mood Induction for Reducing the Formation of Nocebo Effects from Side Effect Information

Exploratory study of nocebo effect in senior medical students

Background

Νocebo Effect is known to induce adverse symptoms after negative expectations which can be manifested on a physical and psychological level. As 6th year medical students often face a wide range of clinical challenges and may be prone to negative expectations or beliefs affecting their pre-clinical and clinical success, we want to investigate how they are affected by the Nocebo Effect.

Objective

To investigate whether a nocebo effect can be induced when exposing final-year students to the clinical context of their training.

Methods

We used verbal suggestions as a nocebo mechanism and by using three tools, the Illness Attitude Scales, the Symptom Checklist-90, and the State-Trait Anxiety Inventory, we examined the difference in scores on measures of psychometric parameters in 33 participants who were on their 6th year medical and attended three clinics for the first time during their education. The administrations were given before and after attending each clinic, and negative verbal suggestions were given prior to the first administration. We also measured whether the overall number of clinics, had an effect on psychometric parameters.

Results

The results revealed a significant increase in second administration overall in the three clinics in specific psychometric parameters but no statistically significant difference was observed after attending consecutive clinics.

Conclusion

Students reported the occurrence of adverse symptoms in the investigated psychometric parameters, which should be noted in order to avoid potential educational clinical failure.

Evidence and sources of placebo effects in transcranial direct current stimulation during a single session of visuospatial working memory practice

Transcranial direct current stimulation (tDCS) can be used to non-invasively augment cognitive training. However, the benefits of tDCS may be due in part to placebo effects, which have not been well-characterized. The purpose of this study was to determine whether tDCS can have a measurable placebo effect on cognitive training and to identify potential sources of this effect. Eighty-three right-handed adults were randomly assigned to one of three groups: control (no exposure to tDCS), sham tDCS, or active tDCS. The sham and active tDCS groups were double-blinded. Each group performed 20 min of an adapted Corsi Block Tapping Task (CBTT), a visuospatial working memory task. Anodal or sham tDCS was applied during CBTT training in a right parietal-left supraorbital montage. After training, active and sham tDCS groups were surveyed on expectations about tDCS efficacy. Linear mixed effects models showed that the tDCS groups (active and sham combined) improved more on the CBTT with training than the control group, suggesting a placebo effect of tDCS. Participants' tDCS expectations were significantly related to the placebo effect, as was the belief of receiving active stimulation. This placebo effect shows that the benefits of tDCS on cognitive training can occur even in absence of active stimulation. Future tDCS studies should consider how treatment expectations may be a source of the placebo effect in tDCS research, and identify ways to potentially leverage them to maximize treatment benefit.

The Nocebo Effect: A Bias in Clinical Practice-An Ethical Approach

BACKGROUND

The nocebo effect is often disregarded in medical practice and is certainly much less known than the placebo effect, although, in reality, both can influence therapeutic decision making and the quality of life of patients. However, the nocebo effect raises a number of issues not only of a practical nature related to clinical activity but also ethical dilemmas related to the observance of the patient's autonomy, nonmaleficence, or informed consent and the information on which it is based.

AREAS OF UNCERTAINTY

The ethical dilemmas raised by the nocebo effect revolve around how informed consent can be achieved, the accuracy and volume of information that is transmitted to the patient, and how to report negative side effects of therapeutic treatment.

DATA SOURCES

In September 2023, a narrative analysis of the literature was conducted using a combination of keywords such as nocebo, placebo, ethics, therapeutic relationship from PubMed, Scopus, Google Scholar, and so on, as well as from official documents developed at an international level (World Health Organization), for a period of 10 years (2012-2021).

RESULTS

Analyzing the articles that remarked upon the significant impact of ethics in nocebo research or in the therapeutic relationship, we can state that the existence of several relevant issues of interest have been detected regarding the ethical use of nocebo and its impact in research or in clinics and thus the need for proper knowledge and management of the impact of nocebo effects. The ethical paradox of obtaining informed consent with the 2 goals, first, the need for complete information and second, the preservation of the autonomy of the patient, respectively, that of "primum non-nocere" and of avoiding unnecessary harm by revealing probable adverse effects is a point of interest for numerous studies. The potential for a nocebo effect is present when we inform patients about the risks and benefits of treatment, there being a clear link between the moral and ethical duty to inform patients and the need to avoid situations that increase the nocebo impact on how the disease or the adverse effects of the treatment are perceived. Adapting information about the side effects of medicines should focus on ensuring a balance between transparency and caution, especially in patients with a high potential for nocebo effect.

CONCLUSIONS

The nocebo effect had for a long time been unknown or denied, although it can interfere with the results of the treatment used. As the nocebo phenomenon becomes increasingly known in medical practice, the clinical and ethical implications are identified by medical staff, and nocebo's adverse responses are no longer ignored.

Association between personality traits and placebo effects: a preregistered systematic review and meta-analysis

ABSTRACT

Placebo effects are ubiquitous yet highly variable between individuals and therefore strongly affect clinical trial outcomes such as pain relief. It is unclear whether dispositional psychological traits influence responsiveness to placebo. This preregistered meta-analysis and systematic review synthesized the literature investigating the association between personality traits and placebo effects. Based on 21 studies with 798 participants, we performed formal meta-analyses for 10 different personality traits, including behavioral inhibition, fun seeking, goal-drive persistence, reward responsiveness, empathic concern, empathic fantasy, perspective-taking, personal distress, optimism, and anxiety. We did not find evidence of associations between any of these traits and magnitude of placebo effects, which was supported by equivalence tests. Furthermore, we did not find evidence for moderating factors such as placebo manipulation type (conditioning or nonconditioning) or condition (pain or nonpain). These findings challenge the notion that personality influences responsiveness to placebos and contradict its utility for identifying placebo "responders" and "nonresponders."

Social communication pathways to COVID-19 vaccine side-effect expectations and experience

OBJECTIVE

Negative beliefs about medication and vaccine side-effects can spread rapidly through social communication. This has been recently documented with the potential side-effects from the COVID-19 vaccines. We tested if pre-vaccination social communications about side-effects from personal acquaintances, news reports, and social media predict post-vaccination side-effect experiences. Further, as previous research suggests that side-effects can be exacerbated by negative expectations, we assessed if personal expectations mediate the relationships between social communication and side-effect experience.

METHOD

In a prospective longitudinal survey (N = 551), COVID-19 vaccine side-effect information from three sources-social media posts, news reports, and first-hand accounts from personal acquaintances-as well as side-effect expectations, were self-reported pre-vaccination. Vaccination side-effect experience was assessed post-vaccination.

RESULTS

In multivariate regression analyses, the number of pre-vaccination social media post views (β = 0.17) and impressions of severity conveyed from personal acquaintances (β = 0.42) significantly predicted an increase in pre-vaccination side-effect expectations, and the same variables (βs = 0.11, 0.14, respectively) predicted post-vaccination side-effect experiences. Moreover, pre-vaccination side-effect expectations mediated the relationship between both sources of social communication and experienced side-effects from a COVID-19 vaccination.

CONCLUSIONS

This study identifies links between personal acquaintance and social media communications and vaccine side-effect experiences and provides evidence that pre-vaccination expectations account for these relationships. The results suggest that modifying side-effect expectations through these channels may change the side-effects following a COVID-19 vaccination as well as other publicly discussed vaccinations and medications.

Shared decision-making practices and patient values in pharmacist outpatient care for rheumatic disease: A multiple correspondence analysis

Purpose: To investigate the value-to-value relationships, relationship between values and patient background, continuation rate of treatment after shared decision-making (SDM), and disease status in order to clarify the values involved in drug therapy decisions for patients with rheumatic disease. Methods: We investigated patient values (efficacy of drug therapy [effectiveness], safety, economics, daily life, and other) and the continuance rate and disease status of treatment after 6 months in 94 patients with rheumatic disease aged ≥18 years who made decisions with pharmacists and physicians in the pharmacy outpatient clinic between September 2019 and April 2021. Multiple correspondence and K-means cluster analyses were performed to show the relationship between values and basic patient information. Results: Among the selected patients, 87% and 47% selected effectiveness for multiple selections and single selection, respectively. Effectiveness was at the center of the graph; three clusters containing other values were placed around it. History of allergy or side effects caused by biologics or Janus kinase inhibitors were in the safety cluster. The non-usage history of biologics or Janus kinase inhibitors was in the economic cluster. Conclusion: Effectiveness was the most important factor for patients with rheumatic disease; the values that patients consider important may shift from effectiveness to other values based on each patient's subjective experience with the treatment and/or the stage of life in which they were treated. It is important to positively link patient values and information about the treatment plan in shared decision-making while establishing rapport with the patient.

The association of affective state with the assimilation of daily pain expectancy and pain experience

ABSTRACT

Expectancies for pain and pain relief are central to experimental models of placebo analgesia and nocebo hyperalgesia, and are a promising target for clinical intervention in patients with chronic pain. Affective states may play an important role in modulating the degree to which expectancies influence pain, broadening the opportunities for intervention targets. However, findings to date have been mixed and mostly limited to laboratory designs. Few studies have examined the interplay of naturally occurring affective states, pain expectancies, and pain experiences in the course of daily life with chronic pain. In the present study, patients with temporomandibular disorder reported their daily pain expectancies and affective states each morning, and their daily pain experience each evening, over a two-week period. Multilevel modeling analyses revealed the association of morning pain expectancies with subsequent pain experiences was moderated by morning positive affective state (B=.04, SE=.02, t=2.00, p=.046), such that the congruent assimilation of a low pain expectancy with a low pain experience was starkest when morning positive affect was higher than usual. Relatedly, higher morning positive affect predicted greater odds of experiencing a match between pain expectancies and pain experience when the expectation was for low, but not high, pain levels (OR: 1.19, CI: 1.01-1.41, p=.03). Negative affect, in contrast, did not significantly influence the assimilation of high pain expectancies with high pain experiences. These findings extend prior experimental studies by showing that the association of daily pain expectancies with pain experience varies as a function of affective state.

A social affective neuroscience lens on placebo analgesia

Pain is a fundamental experience that promotes survival. In humans, pain stands at the intersection of multiple health crises: chronic pain, the opioid epidemic, and health disparities. The study of placebo analgesia highlights how social, cognitive, and affective processes can directly shape pain, and identifies potential paths for mitigating these crises. This review examines recent progress in the study of placebo analgesia through affective science. It focuses on how placebo effects are shaped by expectations, affect, and the social context surrounding treatment, and discusses neurobiological mechanisms of placebo, highlighting unanswered questions and implications for health. Collaborations between clinicians and social and affective scientists can address outstanding questions and leverage placebo to reduce pain and improve human health.

The Nocebo Effect: A Review of Contemporary Experimental Research

BACKGROUND

Nocebo effect, the occurrence of adverse symptoms fallowing an inactive treatment, is much less understood than its opposite, placebo effect. This systematic review of contemporary studies exploring the nocebo effect focuses on (1) the mechanisms underlying the nocebo effect, (2) the characteristics of participants exhibiting a more intensive nocebo response, and (3) the circumstances that might reduce or prevent the nocebo effect.

METHOD

We included experimental nocebo studies published in English that examined the occurrence of nocebo in various domains (i.e., types of sensations and symptoms) and different levels of nocebo response (e.g., performance, self-assessment) and in different populations of participants (healthy and clinical). Using Web of Science, PsycInfo and PubMed, we identified 25 papers (35 studies) that met our criteria with a total of N = 2614 participants, mostly healthy volunteers.

RESULTS

Nocebo was invoked by manipulating expectations, conditioning or both. A narrative content synthesis was conducted. Nocebo was successfully invoked in a range of domains (e.g., pain, nausea, itch, skin dryness) and levels (sensory, affective, psychological, and behavioral). Various characteristics of the conditioning procedure and participants' emotions, expectations, and dispositions are found to be related to the nocebo response, which sheds insight into the possible mechanisms of the nocebo effect. Strategies successful and unsuccessful in diminishing the nocebo response are identified. Limitations of this review include a small sample of studies.

CONCLUSION

These findings point to the universality of nocebo as well as to the importance of participant characteristics and experimental circumstances in invoking the nocebo effect. Further research should examine the nocebo effect in clinical populations.

Predicting Expectations of Side-Effects for Those Which Are Warned Versus Not Warned About in Patient Information Leaflets

BACKGROUND

Research investigating predictors of side-effect expectations is disparate and largely based on hypothetical vignettes.

PURPOSE

To carry out a secondary analysis of a randomized controlled trial and investigate the predictors of side-effect expectations for side-effects that were, or were not, warned about.

METHODS

Two hundred and three healthy adults completed measures concerning demographics, psychological factors, baseline symptoms, and medication-related beliefs before reading one of two types of patient information leaflet (PIL) (standard or positively framed PIL) for a sham medication and asking them about their side-effect expectations. Associations between these measures and side-effect expectations whilst controlling for the PIL received were assessed using regression analyses.

RESULTS

82.8% of participants expected side-effects that were warned about in the PIL, and 29.1% expected side-effects that were not warned about. Participants who were younger, from White backgrounds, less optimistic, experienced increased anxiety and received the standard PIL were more likely to expect side-effects that were warned about. Those with higher beliefs about medicine overuse and lower trust in medicine development were more likely to expect side-effects that were not warned about. Higher somatization, baseline symptoms, modern health worries scores, and lower trust in pharmaceutical companies were associated with increased expectations for all side-effects. The results suggest we can not only rely on altering side-effect risk communication to reduce side-effect expectations and therefore nocebo effects. We must also consider patients' beliefs about trust in medicines. More work is needed to investigate this in a patientsample in which the medication is known to them.

Nocebo Effects on Perceived Muscle Soreness and Exercise Performance Following Unaccustomed Resistance Exercise: A Pilot Study

The purpose of this study was to investigate the effects of nocebo administration on perceived soreness and exercise performance following unaccustomed resistance exercise. Untrained males were randomly assigned to one of two treatments: (1) control or (2) negative-belief. For the negative-belief group, participants were given a capsule before exercise containing 400 mg of an inert substance (gluten-free cornstarch) and were told the supplement would increase muscle soreness. The control group received no treatment. An algometer and pain scale was used to obtain soreness, and a goniometer was used to measure elbow range of motion (ROM). Participants completed an eccentric bicep curl pyramid with their non-dominant arm. Rate of perceived exertion (RPE) and repetitions were recorded. Then, 48 h after the initial exercise bout, participants repeated all procedures. Perceived soreness, ROM, average RPE, and total repetitions performed were analyzed. Perceived soreness was significantly higher in both control and negative-belief groups 48 h after exercise (p < 0.001; η² = 0.23). ROM was significantly lower 48 h post in the negative-belief group (p = 0.004; d = 1.83) while no differences existed for controls (p = 0.999; d = 0.16). Average RPE was unaffected between groups (p = 0.282; η² = 0.07). Total repetitions were significantly lower 48 h post in the negative-belief group (p < 0.001; d = 2.51) while no differences existed for the controls (p = 0.999; d = 0.08). Findings suggest that 48 h after unaccustomed resistance exercise, negative expectation does not worsen soreness but hinders ROM and exercise performance.

Maximizing placebo response in neurological clinical practice

The placebo effect is a widely recognized phenomenon in clinical research, with a negative perception that it could hide the "true" drug effect. In clinical care its positive potential to increase known drug effects has been neglected for too long. The placebo and nocebo responses have been described in many neurologic disorders such as Parkinson's, Huntington's and Alzheimer's diseases, restless leg syndrome, tics, essential tremor, dystonia, functional movement disorders, neuropathic pain, headaches, migraine, amyotrophic lateral sclerosis, myasthenia gravis, chronic inflammatory demyelinating polyneuropathy, multiple sclerosis and epilepsy. Knowledge regarding placebo mechanisms and their consequences on clinical outcome have greatly improved over the last two decades. This evolution has led to reconsiderations of the importance of placebo response in the clinic and has given several clues on how to improve it in daily practice. In this chapter, we first illustrate "why," e.g. the reasons (relevance to clinical practice, help in differential diagnosis/treatment of psychogenic movements, clinical impact, proven neurobiological grounds, health economic potential), and "how," e.g. the means (increase patients' knowledge, increase learning, improve patient-doctor relationship, increase Hawthorne effect, increase positive/decrease negative expectations (the Rosenthal effect), personalize placebo response), the placebo should be maximized (and nocebo avoided) in neurological clinical practice. Future studies regarding more specific neurobiological mechanisms will allow a finer tuning of placebo response in clinical practice. The use of placebo in clinical practice raises ethical issues, and a recent expert consensus regarding placebo use in the clinic is a first step to future guidelines necessary to this field.

A test of psychological and electrodermal changes immediately after the delivery of 3 analgesic treatment messages

Introduction:

Placebo analgesia often results when a pain reduction treatment message is delivered to a patient or research participant. Little information exists regarding the psychological changes that are immediately triggered by the delivery of a treatment message.

Objectives:

This experiment tested the impact of 3 different analgesic treatment messages on the expectations, feelings, and electrodermal activity of participants anticipating a pain stimulus.

Methods:

In laboratory sessions, healthy participants (N = 138) were randomly assigned to 1 of 4 conditions in a between-subject design. The design included a no treatment message control condition and 3 treatment message conditions: a standard analgesic message, an analgesic treatment with side-effect message, and a double-blind analgesic message. After the treatment message manipulation, measures were taken of: treatment efficacy expectations, pain experience expectations, pretask anxiety, positive affect, negative affect, and electrodermal activity.

Results:

Overall, the dependent measures showed relatively few correlations. Furthermore, across all 3 message conditions, treatment-specific expectations were greatly increased compared with the control condition. Finally, participants in the double-blind message condition displayed elevated negative affect.

Conclusion:

All 3 analgesic treatment messages produced a stronger immediate influence on treatment efficacy expectations than on the other dependent measures. Treatment messages can alter negative affect along with expectancies. The low correlations found between dependent measures suggest that different patterns of psychological responses may emerge from analgesic treatment messages depending on contextual factors.