Dataset Information

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

ABSTRACT:

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.

SUBMITTER: Frisaldi E

PROVIDER: S-EPMC10582987 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature

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Publications

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

Frisaldi Elisa E Shaibani Aziz A Benedetti Fabrizio F Pagnini Francesco F

BMJ open 20231017 10

<h4>Objectives</h4>This review aimed to summarise the existing knowledge about placebo and nocebo effects associated with pharmacological interventions and their mechanisms.<h4>Design</h4>Umbrella review, adopting the Assessment of Multiple Systematic Reviews 2 tool for critical appraisal.<h4>Data sources</h4>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, narrat ...[more]

PMID: 37848293

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Project description:BackgroundThere is a relationship between the application of physical restraints and negative physiological and psychological effects on critically ill patients. Many organizations have supported and advocated minimizing the use of physical restraints. However, it is still common practice in many countries to apply physical restraints to patients in intensive care.ObjectiveThis study aimed to assess the effectiveness of various non-pharmacological interventions used to minimize physical restraints in intensive care units and provide a supplement to the evidence summary for physical restraints guideline adaptation.MethodsBased on the methodology of umbrella review, electronic databases, including Cochrane Database of Systematic Reviews, Joanna Briggs Institute Database of Systematic Reviews and Implementation Reports, MEDLINE, EMBASE, CINAHL, Web of Science, PsycInfo/Psyc Articles/Psychology and Behavioral Science Collection, China National Knowledge Infrastructure, SinoMed, and Wanfang Data, were searched to identify systematic reviews published from January 2016 to December 2020. Two independent reviewers undertook screening, data extraction, and quality appraisal. The methodological quality of systematic reviews was evaluated by AMSTAR 2. Evidence quality of each intervention was assessed according to GRADE. The corrected covered area was calculated as a measure of overlap.ResultsA total of 47 systematic reviews were included in the umbrella review, of which six were evaluated as high quality, five were of moderate quality, and the rest were of low or critically low quality. The corrected covered area range was from 0.0 to 0.269, which indicated that there was mild overlap between systematic reviews. The included systematic reviews evaluated various types of non-pharmacological interventions for minimizing physical restraints in intensive care units, which included multicomponent interventions involving healthcare professionals' education, family engagement/support, specific consultations and communication, rehabilitation and mobilization (rehabilitation techniques, early mobilization, inspiratory muscle training), interventions related to reducing the duration of mechanical ventilation (weaning modes or protocols, ventilator bundle or cough augmentation techniques, early tracheostomy, high-flow nasal cannula), and management of specific symptoms (delirium, agitation, pain, and sleep disturbances).ConclusionThe number of systematic reviews related to physical restraints was limited. Multicomponent interventions involving healthcare professionals' education may be the most direct non-pharmacological intervention for minimizing physical restraints use in intensive care units. However, the quality of evidence was very low, and conclusions should be taken with caution. Policymakers should consider incorporating non-pharmacological interventions related to family engagement/support, specific consultations and communication, rehabilitation and mobilization, interventions related to reducing the duration of mechanical ventilation, and management of specific symptoms as part of the physical restraints minimization bundle. All the evidence contained in the umbrella review provides a supplement to the evidence summary for physical restraints guideline adaptation.Systematic review registrationhttps://www.crd.york.ac.uk/prospero/display_record.php?RecordID=242586, identifier: CRD42021242586.

Dataset Information

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

Objectives

Design

Data sources

Outcome measures

Results

Conclusions

Funding

Prospero registration number

Publications

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

Similar Datasets

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