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International Review of Neurobiology 2020The power of placebos is commonly associated with the placebo effect. In contrast, detrimental effects related to the use of a placebo are little studied and less well... (Review)
Review
The power of placebos is commonly associated with the placebo effect. In contrast, detrimental effects related to the use of a placebo are little studied and less well recognized. This chapter covers the nocebo and lessebo effects defined, respectively, as expectation of harm in the form of adverse events in a placebo arm and reduction of therapeutic benefit due to the uncertainty of being allocated to placebo. The lessebo effect is a more recent concept and has been described only in depression, schizophrenia and Parkinson's disease. The nocebo response was evaluated in many neurological diseases, including epilepsy, multiple sclerosis, Parkinson's disease, Alzheimer's disease, restless leg syndrome, among others. Meta-analyses of randomized controlled trials in these conditions reveal a significant variability of the magnitude of the nocebo response and that factors related to study design, study participants or neurological disease can be associated with a nocebo response, although with the opposing findings across conditions. The knowledge about neurobiological mechanisms of the nocebo effect is poor for neurological diseases, and most of the information has been generated in pain. Functional neuroimaging suggests the existence of a distinct network for the anticipation and the experience of a hyperalgesia nocebo response. Different types of neurotransmitters have been involved, including cholecystokinin, dopamine and opioids. Recognizing the potential impact of nocebo and lessebo effects, mitigating strategies are in development with application to clinical research and clinical practice, such as a contextualized informed consent process, alternative study designs and enhancement of patient-physician communication.
Topics: Anticipation, Psychological; Conditioning, Psychological; Controlled Clinical Trials as Topic; Humans; Informed Consent; Nervous System Diseases; Nocebo Effect; Patient Selection; Placebo Effect; Placebos
PubMed: 32563285
DOI: 10.1016/bs.irn.2020.04.005 -
International Review of Neurobiology 2020The placebo effect in many areas of neurological therapeutics is common and prominent. The importance of the response means that any new treatment must account for the... (Review)
Review
The placebo effect in many areas of neurological therapeutics is common and prominent. The importance of the response means that any new treatment must account for the placebo effect, but this in turn raises major challenges as to how to conduct scientifically meaningful research in an ethically acceptable fashion. Basic principles that may be in tension with one another are those of beneficence and respect for autonomy. It may be challenging to respect autonomy if the scientific design of a study depends upon the use of deception, but this is often mitigated by the information provided to trial participants as part of the informed consent process. Deception is a particular challenge if placebos are to be used in a clinical/therapeutic setting, outside the context of a clinical trial. While practice-based placebo use may on occasion be both beneficial and ethically acceptable, close attention must then be paid to ensuring that basic ethical principles are respected and that placebos are either prescribed in an open and honest fashion, or that any deception is authorized.
Topics: Deception; Ethics, Medical; Humans; Informed Consent; Nervous System Diseases; Placebo Effect; Placebos
PubMed: 32563286
DOI: 10.1016/bs.irn.2020.03.030 -
International Review of Neurobiology 2020Placebos impact epilepsy in a number of ways. Through randomized clinical trials, explicit clinical use, and also through implicit clinical use, placebos play a role in... (Review)
Review
Placebos impact epilepsy in a number of ways. Through randomized clinical trials, explicit clinical use, and also through implicit clinical use, placebos play a role in epilepsy. This chapter will discuss the reasons placebo is used, the determinants of placebo response in epilepsy, observations about placebo specific to epilepsy, and ways in which clinical trial design is impacted by placebo.
Topics: Animals; Anticonvulsants; Clinical Trials as Topic; Epilepsy; Humans; Models, Statistical; Outcome Assessment, Health Care; Placebo Effect; Placebos; Research Design
PubMed: 32563290
DOI: 10.1016/bs.irn.2020.03.033 -
Perspectives in Biology and Medicine 2023The objective of this essay is to develop the argument that placebos are a species of metaphor and to demonstrate that an analysis of the figurative trope can help us...
The objective of this essay is to develop the argument that placebos are a species of metaphor and to demonstrate that an analysis of the figurative trope can help us elucidate the power of the placebo response. The cognitive and embodied responses to both metaphors and placebos stem from the transfer of meaning between two domains, each with rich allusive properties that in turn depend on highly ramified and interconnected neural webs. Metaphors and placebos require an appropriate cultural backdrop for their linguistic and cognitive work and are dependent on shared social forms of life. More specifically, metaphors rely on an intersubjective connection and imply that a relational entanglement between doctor and patient is necessary to the effect of placebos in the clinical setting.
Topics: Humans; Metaphor; Placebo Effect; Placebos; Physician-Patient Relations; Cognition
PubMed: 38661934
DOI: 10.1353/pbm.2023.a902033 -
Naunyn-Schmiedeberg's Archives of... Nov 2022Our aims were to provide updated information on placebo/nocebo effect and the potential use of placebo in clinical practice. This article can only provide a rough... (Review)
Review
Our aims were to provide updated information on placebo/nocebo effect and the potential use of placebo in clinical practice. This article can only provide a rough overview on the placebo and nocebo effect and is intended to serve as a starting point for the reader to go deeper into the corresponding literature. The placebo effect has been observed in multiple medical conditions, after oral administration, with manual therapies as well as with surgery and invasive procedures. The use of placebo in clinical trials is fundamental, although the ethics of its use is under discussion. The placebo may behave like a drug from the pharmacokinetic and pharmacodynamic point of view and can also be associated with adverse events (nocebo effect). Placebo can modify treatment by increasing or decreasing the effects of drugs. The factors associated with the occurrence of placebo effect are multiple, but in addition to those that depend on the placebo itself, the doctor-patient relationship would be the most important. As a result of findings that were published in the last two decades, the psycho-neurobiological basis of placebo is becoming better understood, although further studies are needed. In conclusion, the placebo effect in the clinic exhibits weak to moderate intensity. Placebo, in addition to its use in the clinical trial, should be considered another therapeutic remedy either as stand alone or in association with treatment, and could be useful in certain circumstances. The use of placebo should be regulated by the European health authorities through a guide in clinical practice that will improve patient care.
Topics: Humans; Nocebo Effect; Physician-Patient Relations; Placebo Effect
PubMed: 35943515
DOI: 10.1007/s00210-022-02280-w -
Acta Orthopaedica Oct 2021
Topics: Humans; Placebo Effect
PubMed: 34431744
DOI: 10.1080/17453674.2021.1969155 -
Annals of Behavioral Medicine : a... Oct 2022Choice has been proposed as a method of enhancing placebo effects. However, there have been no attempts to systematically evaluate the magnitude, reliability, and... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Choice has been proposed as a method of enhancing placebo effects. However, there have been no attempts to systematically evaluate the magnitude, reliability, and moderators of the influence of choice on the placebo effect.
PURPOSE
To estimate the effect size of choice on the placebo effect and identify any moderators of this effect.
METHODS
Web of Science, PsycINFO, EMBASE, and PubMed were systematically searched from inception to May 2021 for studies comparing placebo treatment with any form of choice over its administration (e.g., type, timing) to placebo treatment without choice, on any health-related outcome. Random-effects meta-analysis was then used to estimate the effect size associated with the influence of choice on the placebo effect. Meta-regression was subsequently employed to determine the moderating effect of factors such as type of choice, frequency of choice, and size of the placebo effect without choice.
RESULTS
Fifteen independent studies (N = 1,506) assessing a range of conditions, including pain, discomfort, sleep difficulty, and anxiety, met inclusion criteria. Meta-analysis revealed that choice did significantly enhance the placebo effect (Hedges' g = 0.298). Size of the placebo effect without choice was the only reliable moderator of this effect, whereby a greater effect of choice was associated with smaller placebo effects without choice.
CONCLUSIONS
Treatment choice can effectively facilitate the placebo effect, but this effect appears more pronounced in contexts where the placebo effect without choice is weaker. Because most evidence to date is experimental, translational studies are needed to test whether providing choice in clinical scenarios where placebo effects are weaker may help boost the placebo effect and thereby improve patient outcomes.
Topics: Anxiety Disorders; Humans; Placebo Effect; Reproducibility of Results; Research Design; Sleep Initiation and Maintenance Disorders
PubMed: 35022650
DOI: 10.1093/abm/kaab111 -
European Journal of Obstetrics,... Mar 2020To determine whether electronic bladder diaries are associated with a larger placebo effect than paper diaries in studies of overactive bladder (OAB). To identify any... (Review)
Review
OBJECTIVE
To determine whether electronic bladder diaries are associated with a larger placebo effect than paper diaries in studies of overactive bladder (OAB). To identify any other factors in study design that may influence the placebo effect.
STUDY DESIGN
This is a secondary analysis of a previous systematic review and network meta-analysis on the efficacy and tolerability of mirabegron. Each study was analysed and placebo response rate (PRR) was calculated. Statistical analysis was used to look for associations with different factors and PRR.
RESULTS
The PRR was considerable in the studies analysed (10.5 % when calculated for change in number of micturitions over 24 h and 41.2 % for change in urgency urinary incontinence episodes over 24 h). Paper bladder diaries were associated with a significantly larger placebo response rate than electronic (10.76 % vs 10.22 %), although this may be clinically small. The size of study had a moderate positive correlation with PRR. Length of bladder diary was not associated with increased PRR.
CONCLUSIONS
The PRR in studies of OAB is varied and significant. It is clear that it can be affected by factors in study design including type of bladder diary. When designing clinical studies this should be borne in mind. Equally, when attempting to optimise patient care, the benefit of the therapeutic encounter should be remembered.
Topics: Acetanilides; Adrenergic beta-3 Receptor Agonists; Data Collection; Humans; Patient Reported Outcome Measures; Placebo Effect; Thiazoles; Urinary Bladder, Overactive
PubMed: 32018195
DOI: 10.1016/j.ejogrb.2020.01.023 -
Journal of Sport Rehabilitation May 2021While placebo effects are well recognized within clinical medicine, "nocebo effects" have received much less attention. Nocebo effects are problems caused by negative... (Review)
Review
While placebo effects are well recognized within clinical medicine, "nocebo effects" have received much less attention. Nocebo effects are problems caused by negative expectations derived from information or treatment provided during a clinical interaction. In this review, we examine how nocebo effects may arise following pediatric concussion and how they may worsen symptoms or prolong recovery. We offer several suggestions to prevent, lessen, or eliminate such effects. We provide recommendations for clinicians in the following areas: terminology selection, explicit and implicit messaging to patients, evidence-based recommendations, and awareness of potential biases during clinical interactions. Clinicians should consider the empirically grounded suggestions when approaching the care of pediatric patients with concussion.
Topics: Brain Concussion; Child; Humans; Nocebo Effect; Placebo Effect
PubMed: 34050035
DOI: 10.1123/jsr.2020-0519 -
International Review of Neurobiology 2020
Topics: Humans; Nervous System Diseases; Placebo Effect
PubMed: 32563295
DOI: 10.1016/S0074-7742(20)30100-8