Clinically meaningful nocebo effect occurs in acupuncture treatment: a systematic review

Mind games in dentistry: confounded evidence suggests a substantial nocebo response in dental impaction pain model

DESIGN

A systematic review and metaanalysis of randomized clinical trials (RCTs).

DATA SOURCES

Electronic search was conducted in PubMed, Embase, Scopus, Web of Science and the Cochrane Central Register of Controlled Trials (CENTRAL), on 22 May 2021.

SELECTION CRITERIA

Eligibility criteria included parallel-group placebo-controlled RCTs assessing analgesics after third molar (M3) surgery in healthy patients, reporting the number of patients with at least one drug-related adverse event (AE), and being published in English.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently screened all identified articles against the eligibility criteria, and performed quality assessment and data extraction. Any disagreements were resolved by discussion involving a third reviewer. The primary outcome was the pooled rate of drug-related AEs in placebo and active arms of RCTs assessing analgesic treatment following M3 surgery. Secondary outcome was the drug-related dropout rates in the same setting.

RESULTS

A total of 50 RCTs in 47 articles were included in the analyses. The pooled rates of patients with AE ≥ 1 in the placebo and active arms were 22.8% and 20.6%, respectively. The pooled drug-related dropout rates in the placebo and active arms were 0.24% and 0.08%, respectively. There were no significant risk differences in patients with AE ≥ 1 and drug-related dropouts (p = 0.61 and p = 0.94; respectively). High statistical heterogeneity was found for the proportion of patients with AE ≥ 1 (I2 = 79.7%, p < 0.001), but not for drug-related dropout rates (I2 = 0%, p = 1.00).

CONCLUSION

Patients in the placebo arm reported AEs at a similar frequency as patients receiving active treatment, suggesting that most analgesic-related AEs after M3 surgery may be attributed to the nocebo phenomenon.

Guided Self-rehabilitation Contract vs conventional therapy in chronic peripheral facial paresis: VISAGE, a multicenter randomized controlled trial

BACKGROUND

One year after persistent peripheral facial paresis (PFP), prescriptions of conventional rehabilitation are often downgraded into maintenance rehabilitation or discontinued, the patient entering what is seen as a chronic stage. This therapeutic choice is not consistent with current knowledge about behavior-induced plasticity, which is available all life long and may allow intense sensorimotor rehabilitation to remain effective. This prospective, randomized, multicenter single-blind study in subjects with chronic unilateral PFP evaluates changes in facial motor function with a Guided Self-rehabilitation Contract (GSC) vs. conventional therapy alone, carried out for six months.

METHODS

Eighty-two adult subjects with chronic unilateral PFP (> 1 year since facial nerve injury) will be included in four tertiary, maxillofacial surgery (2), otolaryngology (1) and rehabilitation (1) centers to be randomized into two rehabilitation groups. In the experimental group, the PM&R specialist will implement the GSC method, which for PFP involves intensive series of motor strengthening performed daily on three facial key muscle groups, i.e. Frontalis, Orbicularis oculi and Zygomatici. The GSC strategy involves: i) prescription of a daily self-rehabilitation program, ii) teaching of the techniques involved in the program, iii) encouragement and guidance of the patient over time, in particular by requesting a quantified diary of the work achieved to be returned by the patient at each visit. In the control group, participants will benefit from community-based conventional therapy only, according to their physician's prescription. The primary outcome measure is the composite score of Sunnybrook Facial Grading System. Secondary outcome measures include clinical and biomechanical facial motor function quantifications (Créteil Scale and 3D facial motion analysis through the Cara system), quality of life (Facial Clinimetric Evaluation and Short-Form 12), aesthetic considerations (FACE-Q scale) and mood representations (Hospital Anxiety and Depression scale). Participants will be evaluated every three months by a blinded investigator, in addition to four phone calls (D30/D60/D120/D150) to monitor compliance and tolerance to treatment.

DISCUSSION

This study will increase the level of knowledge on the effects of intense facial motor streng-          Facial paralysisthening prescribed through a GSC in patients with chronic peripheral facial paresis.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04074018 . Registered 29 August 2019.

PROTOCOL VERSION

Version N°4.0-04/02/2021.

Rapid overview of systematic reviews of nocebo effects reported by patients taking placebos in clinical trials

Background

Trial participants in placebo groups report experiencing adverse events (AEs). Existing systematic reviews have not been synthesized, leaving questions about why these events occur as well as their prevalence across different conditions unanswered.

Objectives

To synthesize the evidence of prevalence of AEs in trial placebo groups across different conditions.

To compare AEs in trial placebo groups with AEs reported in untreated groups within a subset of randomized trials.

Search methods

We searched PubMed for records with the word “nocebo” in the title and “systematic” in any field. We also contacted experts and hand-searched references of included studies.

Study eligibility

We included any systematic review of randomized trials where nocebo effects were reported. We excluded systematic reviews of non-randomized studies.

Participants and interventions

We included studies in any disease area.

Study appraisal and synthesis methods

We appraised the quality of the studies using a shortened version of the Assessment of Multiple Systematic Reviews tool (AMSTAR) tool. We reported medians and interquartile ranges (IQRs) of AEs. Among the trials within the review that included untreated groups, we compared the prevalence of AEs in untreated groups with the prevalence of AEs in placebo groups.

Results

We identified 20 systematic reviews. These included 1271 randomized trials and 250,726 placebo-treated patients. The median prevalence of AEs in trial placebo groups was 49.1% (IQR 25.7–64.4%). The median rate of dropouts due to AEs was 5% (IQR 2.28–8.4%). Within the 15 of trials that reported AEs in untreated groups, we found that the AE rate in placebo groups (6.51%) was higher than that reported in untreated groups (4.25%).

Limitations

This study was limited by the quality of included reviews and the small number of trials that included untreated groups.

Conclusions and implications of key findings

AEs in trial placebo groups are common and cannot be attributed entirely to natural history. Trial methodologies that reduce AEs in placebo groups while satisfying the requirement of informed consent should be developed and implemented.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-3042-4) contains supplementary material, which is available to authorized users.

Nonspecific adverse events in knee osteoarthritis clinical trials: a systematic review

Background

Adverse events (AEs) derived from nonspecific activity of treatments can impair the validity of trials, and even make it difficult to identify specific AEs associated with treatments. To better understand these nonspecific AEs, we investigated the AEs in placebo groups by using knee osteoarthritis clinical trials.

Methods

Randomized, placebo-controlled, knee osteoarthritis trials were identified by searching electronic databases. We determined the rate of patients with AEs and the rate of dropouts caused by AEs in the active and placebo groups. Furthermore, we calculated the rate of patients for individual AEs in the placebo groups. Finally, we performed secondary analyses to identify the factors associated with these rates.

Results

Overall, 272 papers reporting 281 trials were included in the analysis. The rates of patients with AEs were 31.8% in the active groups and 27.4% in the placebo groups. The rate of the placebo groups accounted for 86.2% of the rate of the active groups. The rates of dropouts caused by AEs were 5.2% in the active groups and 4.8% in the placebo groups. The rate of the placebo groups accounted for 92.3% of the rate of the active groups. AEs in the placebo groups included a number of clinical conditions, with elevated alanine aminotransferase (0.59%; 95% CI: 0.46 to 0.77) being the most common objective outcome and headache (4.48%; 95% CI: 4.20 to 4.79) being the most frequent subjective outcome. The rate of patients with AEs and the rate of dropouts caused by AEs were associated with the treatment type, delivery route, and study design.

Conclusions

The nonspecific AEs substantially accounted for the development of AEs in the active groups and included conditions involving the entire body.