Placebo effect in child and adolescent psychiatric trials

Cannabinoids as alleviating treatment for core symptoms of autism spectrum disorder in children and adolescents: a systematic review

INTRODUCTION

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder affecting about 1% of children. The disorder is characterized by difficulties within three core symptoms: social interactions, communication, and restricted or repetitive behavior. There is currently no approved psychopharmacological treatment; however, it is hypothesized that ASD symptoms might be ameliorated by manipulating the endocannabinoid (eCB) system.This study aims to review the existing research on cannabinoids as a potential effective treatment for the core symptoms of ASD in children and adolescents.

METHODS

A literature search was conducted on PubMed, Embase, APA PsychInfo, and Cochrane. The available literature was screened, and studies were included if: the study population consisted of children/adolescents, the treatment involved cannabinoids, and the outcome assessed was the impact on core ASD symptoms.

RESULTS

The search yielded five studies, two RCTs and three cohort studies. All the included studies reported an effect of the cannabinoid treatment; however, most of these effects were non-significant and not related to core symptoms. Only one study found a significant improvement on all three core symptoms. The risk of bias was rated as "high" or "very high" in four studies and as "low" in one study.

DISCUSSION

Although the included studies did not find substantial results regarding core ASD symptoms, they all reported that cannabinoid treatment had other positive effects. However, Long term outcome is unknown, and safety aspects are scarcely discussed.

CONCLUSION

Based on this review, the effect of cannabinoid treatment on ASD core symptoms is not clear; therefore, further studies are required.

Self-Guided Digital Intervention for Depression in Adolescents: Feasibility and Preliminary Efficacy Study

BACKGROUND

Depression in adolescents is a large and growing problem; however, access to effective mental health care continues to be a challenge. Digitally based interventions may serve to bridge this access gap for adolescents in need of care. Digital interventions that deliver components of cognitive behavioral therapy (CBT) have been shown to reduce symptoms of depression, and virtual reality (VR) may be a promising adjunctive component. However, research on these types of treatments in adolescents and young adults is limited.

OBJECTIVE

This study aims to evaluate the feasibility, acceptability, and preliminary efficacy of Spark (v1.0), a 5-week, self-guided, CBT-based digital program using a mobile app and VR experiences to target symptoms of depression in adolescents.

METHODS

A single-arm, open-label study of the Spark program was conducted with a community sample of 30 adolescents and young adults aged 12 to 21 years with self-reported moderate to severe depression symptoms. Participants completed a weekly depression assessment (Patient Health Questionnaire-8) in the app during the 5-week intervention period as well as web-based baseline, postintervention, and 1-month follow-up self-report assessments. The participants also completed a qualitative postintervention interview. For participants aged <18 years, caregivers completed assessments at baseline and postintervention time points. Feasibility outcomes included recruitment rate (the proportion of participants who enrolled in the study divided by the total number of participants screened for eligibility) and retention rate (the proportion of participants who completed postintervention assessments divided by the total number of participants who received the intervention). Acceptability outcomes included engagement with the program and quantitative and qualitative feedback about the program. Preliminary efficacy was evaluated based on the Patient Health Questionnaire-8.

RESULTS

The study recruitment (31/66, 47%) and retention (29/30, 97%) rates were high. Participants provided higher ratings for the ease of use of the Spark program (8.76 out of 10) and their enjoyment of both the mobile app (7.00 out of 10) and VR components (7.48 out of 10) of the program, whereas they provided lower ratings for the program's ability to improve mood (4.38 out of 10) or fit into their daily routines (5.69 out of 10). We observed a clinically and statistically significant reduction in depression scores at postintervention (mean difference 5.36; P<.001) and 1-month follow-up (mean difference 6.44; P<.001) time points.

CONCLUSIONS

The Spark program was found to be a feasible and acceptable way to deliver a self-guided CBT-focused intervention to adolescents and young adults with symptoms of depression. Preliminary data also indicated that the Spark program reduced the symptoms of depression in adolescents and young adults. Future studies should evaluate the efficacy of this intervention in an adequately powered randomized controlled trial.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04165681; https://classic.clinicaltrials.gov/ct2/show/NCT04165681.

The Future of Child and Adolescent Clinical Psychopharmacology: A Systematic Review of Phase 2, 3, or 4 Randomized Controlled Trials of Pharmacologic Agents Without Regulatory Approval or for Unapproved Indications

We aimed to identify promising novel medications for child and adolescent mental health problems. We systematically searched https://clinicaltrials.gov/ and https://www.clinicaltrialsregister.eu/ (from 01/01/2010-08/23/2022) for phase 2 or 3 randomized controlled trials (RCTs) of medications without regulatory approval in the US, Europe or Asia, including also RCTs of dietary interventions/probiotics. Additionally, we searched phase 4 RCTs of agents targeting unlicensed indications for children/adolescents with mental health disorders. We retrieved 234 ongoing or completed RCTs, including 26 (11%) with positive findings on ≥ 1 primary outcome, 43 (18%) with negative/unavailable results on every primary outcome, and 165 (70%) without publicly available statistical results. The only two compounds with evidence of significant effects that were replicated in ≥ 1 additional RCT without any negative RCTs were dasotraline for attention-deficit/hyperactivity disorder, and carbetocin for hyperphagia in Prader-Willi syndrome. Among other strategies, targeting specific symptom dimensions in samples stratified based on clinical characteristics or established biomarkers may increase chances of success in future development programmes.

Improving treatment outcomes for adolescents with borderline personality disorder through a socioecological approach

BACKGROUND

There is a dearth of studies evaluating treatment efficacy for adolescents diagnosed with borderline personality disorder. The few available randomized controlled trials that have been conducted show modest results and treatments appear to have equivalent effects. The current paper draws on (a) the lessons learnt from the last 50 years of psychotherapy research in general and (b) recent advances in mentalization-based understanding of why treatment works, which together point to the importance of following a socioecological approach in the treatment of personality problems in adolescence - a developmental period that insists on a treatment approach that goes beyond the therapist-client dyad.

CASE PRESENTATION

Here, we describe such an approach, and offer a clinical case example with a young 16-year old girl diagnosed with borderline personality disorder, to illustrate what a shift toward a more socioecological approach would entail.

CONCLUSIONS

The clinical impact of the socioecological approach and the potential benefits as illustrated in the current case illustration, offers a framework that justifies and allows for the expansion of service delivery for youth with borderline personality disorder beyond dyadic therapist-client work.

Efficacy and Safety of Duloxetine in Children and Adolescents with Major Depressive Disorder in Japan: A Randomized Double-Blind Placebo-Controlled Clinical Trial Followed by an Open-Label Long-Term Extension Trial

Objective: The goal of this study was to evaluate the efficacy and safety of duloxetine in children and adolescents (9-17 years of age) with major depressive disorder (MDD) in Japan. Methods: This study consists of two clinical trials. First, a 6-week, randomized double-blind placebo-controlled clinical trial (RCT) was conducted. The primary endpoint of RCT was the change in Children's Depression Rating Scale-Revised (CDRS-R) total scores from baseline. Following RCT, an open-label long-term extension trial (OLE) was conducted to investigate the longer-term safety of duloxetine for ∼1 year. Results: In RCT, CDRS-R total score changes from baseline to 6 weeks after the start of administration (primary endpoint) were -21.03 in the duloxetine group (n = 74) and -22.42 in the placebo group (n = 74). No significant difference was observed in the primary endpoint between the groups (p = 0.5587). In addition, no significant difference was observed in secondary endpoints such as CDRS-R response rates. The proportion of patients with ≥1 treatment-emergent adverse event (TEAE) in RCT was significantly higher in the duloxetine group (78.7%) than in the placebo group (62.2%), and most were mild or moderate in severity. Changes in CDRS-R total scores during OLE, in consecutive patients from the duloxetine group in RCT (n = 63), or placebo group (n = 59) in RCT, and newly enrolled patients (n = 28), were -12.1, -11.3, and -17.8, respectively. The proportion of patients with ≥1 TEAE in OLE was 90.5%, 88.1%, and 89.3% in the respective groups, and most of them were mild or moderate in severity. Conclusions: Duloxetine did not show superiority to placebo in efficacy in children and adolescents with MDD in Japan. Overall reported TEAEs were consistent with the currently available duloxetine safety profile and no new safety finding was observed in the two clinical trials.

Sustained, Multifaceted Improvements in Mental Well-Being Following Psychedelic Experiences in a Prospective Opportunity Sample

In the last 15 years, psychedelic substances, such as LSD and psilocybin, have regained legitimacy in clinical research. In the general population as well as across various psychiatric populations, mental well-being has been found to significantly improve after a psychedelic experience. Mental well-being has large socioeconomic relevance, but it is a complex, multifaceted construct. In this naturalistic observational study, a comprehensive approach was taken to assessing well-being before and after a taking a psychedelic compound to induce a "psychedelic experience." Fourteen measures of well-being related constructs were included in order to examine the breadth and specificity of change in well-being. This change was then analysed to examine clusters of measures changing together. Survey data was collected from volunteers that intended to take a psychedelic. Four key time points were analysed: 1 week before and 2 weeks, 4 weeks, and 2 years after the experience (N = 654, N = 315, N = 212, and N = 64, respectively). Change on the included measures was found to cluster into three factors which we labelled: 1) "Being well", 2) "Staying well," and 3) "Spirituality." Repeated Measures Multivariate Analysis of Variance revealed all but the spirituality factor to be improved in the weeks following the psychedelic experience. Additional Mixed model analyses revealed selective increases in Being Well and Staying Well (but not Spirituality) that remained statistically significant up to 2 years post-experience, albeit with high attrition rates. Post-hoc examination suggested that attrition was not due to differential acute experiences or mental-health changes in those who dropped out vs. those who did not. These findings suggest that psychedelics can have a broad, robust and sustained positive impact on mental well-being in those that have a prior intention to use a psychedelic compound. Public policy implications are discussed.

The bottom-up approach: Non-invasive peripheral neurostimulation methods to treat migraine: A scoping review from the child neurologist's perspective

Migraine is a common and invalidating disorder worldwide. Patients of all ages experience the disorder as very impairing regarding their personal and occupational lives. The current approach in migraine therapy is multimodal including lifestyle management, psychoeducation and, if available, psychotherapeutic interventions, and pharmacotherapy. The lack of non-pharmacological and non-invasive treatment options call for new and innovative therapeutic approaches. Peripheral neurostimulation is a relatively new method in migraine management offering a painless and non-pharmacological way of targeting specific mechanisms involved in migraine. This review summarizes 15 recent randomized clinical trials to provide an overview of non-invasive peripheral neurostimulation methods currently available for the treatment of migraine. Efficacy, tolerability, and safety of the different interventions and their feasibility in the pediatric setting are evaluated. Vagal nerve stimulation (VNS), remote electrical neuromodulation (REN) and supraorbital nerve stimulation (SNS) are considered effective in treating acute migraine attacks, the latter being more pronounced in migraine without aura. Regarding migraine prevention, occipital nerve stimulation (ONS) and supraorbital nerve stimulation (SNS) demonstrated efficacy, whereas repetitive neuromuscular magnetic stimulation (rNMS) may represent a further effective option in episodic migraine. REN and rNMS were found to be well-accepted with fewer patients discontinuing treatment than those receiving direct cranial nerve stimulation. In summary, peripheral neurostimulation represents a promising option to complement the multimodal therapy concept for pediatric migraine. In particular, rNMS opens a new field for research and treatment fitting the requirements of "non-invasiveness" for children. Given the reported efficacy, safety, and feasibility, the therapy decision should be made on an individual level.

Effects of open-label placebos in clinical trials: a systematic review and meta-analysis

Open-label placebos (OLPs) are placebos without deception in the sense that patients know that they are receiving a placebo. The objective of our study is to systematically review and analyze the effect of OLPs in comparison to no treatment in clinical trials. A systematic literature search was carried out in February 2020. Randomized controlled trials of any medical condition or mental disorder comparing OLPs to no treatment were included. Data extraction and risk of bias rating were independently assessed. 1246 records were screened and thirteen studies were included into the systematic review. Eleven trials were eligible for meta-analysis. These trials assessed effects of OLPs on back pain, cancer-related fatigue, attention deficit hyperactivity disorder, allergic rhinitis, major depression, irritable bowel syndrome and menopausal hot flushes. Risk of bias was moderate among all studies. We found a significant overall effect (standardized mean difference = 0.72, 95% Cl 0.39–1.05, p < 0.0001, I² = 76%) of OLP. Thus, OLPs appear to be a promising treatment in different conditions but the respective research is in its infancy. More research is needed, especially with respect to different medical and mental disorders and instructions accompanying the OLP administration as well as the role of expectations and mindsets.

Placebo response in pharmacological and dietary supplement trials of autism spectrum disorder (ASD): systematic review and meta-regression analysis

Background

Placebo response in autism spectrum disorder (ASD) might dilute drug-placebo differences and hinder drug development. Therefore, this meta-analysis investigated placebo response in core symptoms.

Methods

We searched ClinicalTrials.gov, CENTRAL, EMBASE, MEDLINE, PsycINFO, WHO-ICTRP (up to July 8, 2018), and PubMed (up to July 4, 2019) for randomized pharmacological and dietary supplement placebo-controlled trials (RCTs) with a minimum of seven days of treatment. Single-group meta-analyses were conducted using a random-effects model. Standardized mean changes (SMC) of core symptoms in placebo arms were the primary outcomes and placebo positive response rates were a secondary outcome. Predictors of placebo response were investigated with meta-regression analyses. The protocol was registered with PROSPERO ID CRD42019125317.

Results

Eighty-six RCTs with 2360 participants on placebo were included in our analysis (87% in children/adolescents). The majority of trials were small, single-center with a duration of 8–12 weeks and published after 2009. Placebo response in social-communication difficulties was SMC = − 0.32, 95% CI [− 0.39, − 0.25], in repetitive behaviors − 0.23[− 0.32, − 0.15] and in scales measuring overall core symptoms − 0.36 [− 0.46, − 0.26]. Overall, 19%, 95% CI [16–22%] of participants were at least much improved with placebo. Caregiver (vs. clinician) ratings, lower risk of bias, flexible-dosing, larger sample sizes and number of sites, less recent publication year, baseline levels of irritability, and the use of a threshold of core symptoms at inclusion were associated with larger placebo response in at least a core symptom domain.

Limitations

About 40% of the trials had an apparent focus on core symptoms. Investigation of the differential impact of predictors on placebo and drug response was impeded by the use of diverse experimental interventions with essentially different mechanisms of action. An individual-participant-data meta-analysis could allow for a more fine-grained analysis and provide more informative answers.

Conclusions

Placebo response in ASD was substantial and predicted by design- and participant-related factors, which could inform the design of future trials in order to improve the detection of efficacy in core symptoms. Potential solutions could be the minimization and careful selection of study sites as well as rigorous participant enrollment and the use of measurements of change not solely dependent on caregivers.

Efficacy, Safety, and Acceptability of Pharmacologic Treatments for Pediatric Migraine Prophylaxis: A Systematic Review and Network Meta-analysis

IMPORTANCE

Migraine is one of the most common neurologic disorders in children and adolescents. However, a quantitative comparison of multiple preventive pharmacologic treatments in the pediatric population is lacking.

OBJECTIVE

To examine whether prophylactic pharmacologic treatments are more effective than placebo and whether there are differences between drugs regarding efficacy, safety, and acceptability.

DATA SOURCES

Systematic review and network meta-analysis of studies in MEDLINE, Cochrane, Embase, and PsycINFO published through July 2, 2018.

STUDY SELECTION

Randomized clinical trials of prophylactic pharmacologic treatments in children and adolescents diagnosed as having episodic migraine were included. Abstract, title, and full-text screening were conducted independently by 4 reviewers.

DATA EXTRACTION AND SYNTHESIS

Data extraction was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis network meta-analysis guidelines. Quality was assessed with the Cochrane Risk of Bias tool. Effect sizes, calculated as standardized mean differences for primary outcomes and risk ratios for discontinuation rates, were assessed in a random-effects model.

MAIN OUTCOMES AND MEASURES

Primary outcomes were efficacy (ie, migraine frequency, number of migraine days, number of headache days, headache frequency, or headache index), safety (ie, treatment discontinuation owing to adverse events), and acceptability (ie, treatment discontinuation for any reason).

RESULTS

Twenty-three studies (2217 patients) were eligible for inclusion. Prophylactic pharmacologic treatments included antiepileptics, antidepressants, calcium channel blockers, antihypertensive agents, and food supplements. In the short term (<5 months), propranolol (standard mean difference, 0.60; 95% CI, 0.03-1.17) and topiramate (standard mean difference, 0.59; 95% CI, 0.03-1.15) were significantly more effective than placebo. However, the 95% prediction intervals for these medications contained the null effect. No significant long-term effects for migraine prophylaxis relative to placebo were found for any intervention.

CONCLUSIONS AND RELEVANCE

Prophylactic pharmacologic treatments have little evidence supporting efficacy in pediatric migraine. Future research could (1) identify factors associated with individual responses to pharmacologic prophylaxis, (2) analyze fluctuations of migraine attack frequency over time and determine the most clinically relevant length of probable prophylactic treatment, and (3) identify nonpharmacologic targets for migraine prophylaxis.

Placebo response rates and potential modifiers in double-blind randomized controlled trials of second and newer generation antidepressants for major depressive disorder in children and adolescents: a systematic review and meta-regression analysis

Children and adolescents with major depressive disorder (MDD) appear to be more responsive to placebo than adults in randomized placebo-controlled trials (RCTs) of second and newer generation antidepressants (SNG-AD). Previous meta-analyses obtained conflicting results regarding modifiers. We aimed to conduct a meta-analytical evaluation of placebo response rates based on both clinician-rating and self-rating scales. Based on the most recent and comprehensive study on adult data, we tested whether the placebo response rates in children and adolescents with MDD also increase with study duration and number of study sites. We searched systematically for published RCTs of SNG-AD in children and/or adolescents (last update: September 2017) in public domain electronic databases and additionally for documented studies in clinical trial databases. The log-transformed odds of placebo response were meta-analytically analyzed. The primary and secondary outcomes were placebo response rates at the end of treatment based on clinician-rating and self-rating scales, respectively. To examine the impact of study duration and number of study sites on placebo response rates, we performed simple meta-regression analyses. We selected other potential modifiers of placebo response based on significance in at least one previous pediatric meta-analysis and on theoretical considerations to perform explorative analyses. We applied sensitivity analyses with placebo response rates closest to week 8 to compare our data with those reported for adults. We identified 24 placebo-controlled trials (2229 patients in the placebo arms). The clinician-rated placebo response rates ranged from 22 to 62% with a pooled response rate of 45% (95% CI 41-50%). The number of study sites was a significant modifier in the simple meta-regression analysis [odds ratio (OR) 1.01, 95% CI 1.01-1.02, p = 0.0003, k = 24) with more study sites linked to a higher placebo response. Study duration was not significantly associated with the placebo response rate. The explorative simple analyses revealed that publication year may be an additional modifier. However, in the explorative multivariable analysis including the number of study sites and the publication year only the number of study sites reached a p value ≤ 0.05. The self-rated placebo response rates ranged from 1 to 68% with a pooled response rate of 26% (95% CI 10-54%) (k = 6; n = 396). This meta-analysis confirms a high pooled placebo response rate in children and adolescents based on clinician ratings, which exceeds that observed in the most recent meta-analysis of placebo effects in adults (36%; 95% CI 35-37%) published in 2016. However, and similar to findings in adults, the pooled response rates based on self-ratings were substantially lower. In accordance with previous meta-analyses, we corroborated the number of study sites as significant modifier. In comparison to the recent adult meta-analysis, the substantially lower number of pediatric studies entails a reduced power to detect modifiers. Future studies should provide more precise and homogenous information to support discovery of potential modifiers and consider no-treatment-if ethically permissible-to allow differentiation between placebo and spontaneous remission rates. If these differ, practicing clinicians should facilitate placebo effects as an addition to the verum effect to maximize benefits. Further research is required to explain the discrepant response rates between clinician and self-ratings.

The Impact of Placebo Response Rates on Clinical Trial Outcome: A Systematic Review and Meta-Analysis of Antidepressants in Children and Adolescents with Major Depressive Disorder

Objective: The high placebo response rate may hamper the discovery of antidepressants in children and adolescents with major depressive disorder (MDD). The aim of the study was to clarify the relationship between the placebo response rate and clinical trial outcomes of the use of antidepressants in children and adolescents, and distinguish main factors responsible to placebo response rate. Methods: The PubMed and Cochrane Library databases were searched for double-blind randomized placebo-controlled trials of the new-generation antidepressants for the acute treatment of MDD in children and adolescents. The response rate differences (RDs) between placebo group and treatment group under different level of placebo response rate were pooled by random-effects meta-analysis. The classification thresholds for low, medium, and high placebo response rate were set at <40%, 40%-50%, and ≥50%, respectively. Predictors of placebo response rate were explored using meta-regression. Results: The analysis included 18 trials with 4365 participants. This study found that the lower the placebo response rate, the greater the efficacy differences between antidepressants and placebo. In the high, moderate, and low placebo response rate subgroups, the response RDs (95% CI) between antidepressants and placebo were 8 (1-14)%, 10 (2-17)%, and 21 (9-32)%, respectively. The meta-regression showed that the number of study sites was the factor most associated with placebo response rate, and that response rate increased 3% with every additional 10 study sites. Conclusions: The clinical outcome was related to the placebo response rates in the clinical trials of antidepressants in children and adolescents with MDD. The efficacy differences between antidepressants and placebo will be maximized when placebo response rates are reduced. The number of study sites was the factor most associated with the placebo response rates.

Lidocaine spray as a local analgesic for intravenous cannulation: a randomized clinical trial

OBJECTIVES

Lidocaine spray is an effective analgesic of mucous membranes. Lidocaine spray is also used during intravenous (i.v.) cannulation, especially in children. However, the analgesic effect of lidocaine spray during i.v. cannulation has not been studied. We aimed to assess the analgesic effectiveness of lidocaine spray during i.v. cannulation.

METHODS

We conducted a randomized, double-blinded, placebo-controlled trial in seventeen healthy adults who received an i.v. cannulation in the right and left elbow, respectively, where the order of application of 60 mg lidocaine spray (Xylocaine 10% pump spray) or placebo spray (chlorhexidine gluconate 0.5% in 70% alcohol base) before i.v. cannulation was randomized. Thus, each participant had an i.v. cannulation in both arms: one with lidocaine spray and the other with placebo spray. The primary outcome was pain intensity assessed by a 100 mm Visual Analogue Scale. The secondary outcomes were adverse events, success rate of i.v. cannulation and the degree of difficulty of i.v. cannulation as estimated by the nurse performing the i.v cannulation.

RESULTS

The pain score (Visual Analogue Scale) during i.v. cannulation was 18.0 mm (interquartile range: 5.0-34.5 mm) after lidocaine application and 21.0 mm (interquartile range: 11.0-30.5) after placebo application. These scores were not significantly different (95% confidence interval: -9.0-11.0, P=0.698). No adverse events occurred and all i.v. cannulations were successful at first attempt.

CONCLUSION

Local administration of lidocaine is not effective in reducing pain during i.v. cannulation.

Completeness of protocols for clinical trials in children submitted to ethics committees

AIM

Studies of published clinical trials involving children have shown frequent omissions in key aspects of design and conduct, but these problems may be artefactual and due to editorial processes and space limitations. To determine actual design and conduct, we analysed the completeness of key domains in trial protocols involving children submitted to Human Research Ethics Committees.

METHODS

The ethics committees of all eight children's hospitals in Australia were invited to participate. De-identified trial protocols submitted for review in 2012 were evaluated using a checklist derived from Consolidated Standards of Reporting Trials, the Cochrane Risk of Bias Tool and Good Clinical Practice guidelines.

RESULTS

Four ethics committees agreed to participate, and 69 protocols were analysed. The domains almost always reported were clustered around the background and trial plan (planned interventions for each group (99%), specific objectives (97%) and scientific background (96%)). Risk-of-bias domains such as random sequence generation and blinding of participants were often reported (75-90%). Domains least reported were clustered around the statistical analysis plan (66%), specified intention-to-treat analysis (54%), the justification for the proposed trial based upon a systematic review (48%) and age-specific outcomes (48%).

CONCLUSIONS

Protocols of trials involving children assessed by ethics committees generally include details on background and basic design, but many key domains in trial design and conduct are not covered. Despite widespread recognition of how problems in the design and conduct of trials may lead to unreliable results, investigators still appear to be omitting key elements in trial protocols.

Low-dose methoxyflurane analgesia in adolescent patients with moderate-to-severe trauma pain: a subgroup analysis of the STOP! study

Introduction

The undertreatment of acute pain presents a significant challenge in the Emergency Department. This post hoc subgroup analysis of a previously reported randomized controlled UK study reports the efficacy and safety of low-dose methoxyflurane analgesia in treating adolescent patients with moderate-to-severe trauma pain.

Patients and methods

Three hundred patients (96 in the adolescent subgroup) aged ≥12 years requiring analgesia for acute trauma pain (pain score of 4-7 on the Numerical Rating Scale) at triage were randomized 1:1 to methoxyflurane (up to 6 mL) or placebo (normal saline), both administered using a Penthrox^® inhaler. The patient could request rescue medication (paracetamol/opioids) at any time. The primary endpoint was the change from baseline in visual analog scale (VAS) pain intensity.

Results

Mean VAS pain score for the adolescent subgroup at baseline was ~ 61 mm. Adjusted mean change in VAS pain intensity from baseline to 5, 10, 15, and 20 minutes was -24.5, -28.1, -31.6, and -31.7 mm for methoxyflurane and -14.6, -18.8, -19.2, and -23.7 mm for placebo, with a statistically significant treatment effect in favor of methoxyflurane overall across all four time points (-9.9 mm; 95% CI: -17.4, -2.4 mm; P=0.0104). Median time to first pain relief was significantly shorter with methoxyflurane (1 minute) than placebo (3 minutes, P<0.0001). Pain relief was reported within 1-10 inhalations in 95.7% of methoxyflurane-treated patients and 64.6% of placebo-treated patients. Rescue medication was requested by two (4.3%) methoxyflurane-treated patients and three (6.3%) placebo-treated patients. Over 95% of patients, physicians, and nurses rated methoxyflurane treatment as "Excellent", "Very Good" or "Good" compared with between 64% and 68% for placebo. The incidence of adverse events was higher with methoxyflurane (51%) than placebo (42%), mostly comprising mild/transient dizziness and headache.

Conclusion

This subgroup analysis shows that low-dose inhaled methoxyflurane is a rapid-acting and effective analgesic in adolescent patients presenting with moderate-to-severe trauma pain.

Trial registration

Clinicaltrials.gov identifier: NCT01420159, EudraCT number: 2011-000338-12.

Omega-3 Fatty Acids as a Treatment for Pediatric Depression. A Phase III, 36 Weeks, Multi-Center, Double-Blind, Placebo-Controlled Randomized Superiority Study

Background: Depressive disorders in childhood and adolescence are a major health problem and often follow a chronic course with severe consequences in later life. Depressive disorders cause the highest burden of disease in this age group across all medical conditions. Treatment adherence is usually very poor, and the use of antidepressant drugs is heavily debated, as suicidal ideations may increase, in particular in the early phase of treatment. Omega-3 fatty acids rich in eicosapentaenoic acid have shown some promising results in over a dozen small scale randomized controlled trials (RCTs) in adult major depressive disorders, with only very few published RCTs in children and adolescents. High-quality phase III RCTs are missing. Methods and Design: The omega-3-pMDD trial is a carefully designed phase III RCT to assess the efficacy and safety of omega-3 fatty acids in the early course of pediatric major depressive disorder (MDD). The study is designed as a multi-center, double-blinded, placebo-controlled, randomized clinical trial enrolling 220 patients aged 8 to 17 years meeting DSM-IV criteria for major depressive disorder of at least moderate symptom severity. After a single-blinded placebo-lead-in phase (7 to 10 days) patients are randomly assigned to omega-3 fatty acids or placebo over 36 weeks. Primary outcomes are changes in depression severity, as well as remission and recovery rates. Secondary outcome measures include the omega-3 index and inflammatory parameters as predictors of response. Data analysis will be performed in the intention-to-treat sample using a (generalized) linear random intercept regression model. Through sampling of blood, hair, saliva, and urine, further putative biological markers for depression and omega-3 fatty response will be investigated. Discussion: This trial addresses if omega-3 fatty acids play a role in the pathogenesis of pediatric MDDs and have antidepressant properties, in particular in clinically depressed children and adolescents with a pre-existing omega-3 fatty acid deficiency, increased markers of oxidative stress, and/or markers of (low grade) inflammation. Ethics and Dissemination: The study was approved by the local ethics committees. The results will be published in peer-reviewed journals irrespective of specific outcomes. Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT03167307.

The Short-Term Placebo Response in Children With Attention-Deficit Hyperactivity Disorder (ADHD)

To assess short-term placebo response in 6- to 13-year-old children with ADHD, children who were administered a double-blind placebo-methylphenidate trial, 1 week each, were included in the analysis. Conners' parents and Teacher Rating scales, the Aggregate Neurobehavioral Student Health and Educational Review inventory, and the Matching Familiar Figure Test were employed. A reduction of 30% or more in one or more of the teachers report subscales was observed in 18.8% of the participants. Attention test performance resulted in 58% of children exhibiting reduction in error rates and 36.2% exhibited longer latency period. Significant correlations between placebo response and methylphenidate response in all of the teachers report subscales were found. Base line severity, learning problem and emotional status were found associated with placebo response. Short-term placebo response should be accounted for in children with ADHD.

Atypical age-dependency of executive function and white matter microstructure in children and adolescents with autism spectrum disorders

Executive function (EF) performance is associated with measurements of white matter microstructure (WMS) in typical individuals. Impaired EF is a hallmark symptom of autism spectrum disorders (ASD) but it is unclear how impaired EF relates to variability in WMS. Twenty-one male youth (8-18 years) with ASD and without intellectual disability and twenty-one typical male participants (TP) matched for age, intelligence quotient, handedness, race and parental socioeconomic status were recruited. Five EF domains were assessed and several DTI-based measurements of WMS [fractional anisotropy (FA), mean diffusivity (MD) and radial diffusivity (RD)] were estimated for eighteen white matter tracts. The ASD group had lower scores for attention (F = 8.37, p = 0.006) and response inhibition (F = 13.09, p = 0.001). Age-dependent changes of EF performance and WMS measurements were present in TP but attenuated in the ASD group. The strongest diagnosis-by-age effect was found for forceps minor, left anterior thalamic radiation and left cingulum angular bundle (all p's ≤ 0.002). In these tracts subjects with ASD tended to have equal or increased FA and/or reduced MD and/or RD at younger ages while controls had increased FA and/or reduced MD and/or RD thereafter. Only for TP individuals, increased FA in the left anterior thalamic radiation was associated with better response inhibition, while reduced RD in forceps minor and left cingulum angular bundle was related to better problem solving and working memory performance respectively. These findings provide novel insight into the age-dependency of EF performance and WMS in ASD, which can be instructive to cognitive training programs.

Pain and placebo in pediatrics: a comprehensive review of laboratory and clinical findings

Pain modulation by placebo mechanisms is one of the most robust and best-studied phenomena, yet almost all research investigating the mechanisms and implications of the placebo analgesia are based on adult research. After highlighting crucial aspects that need to be considered in studying pain modulation in children, this comprehensive review examines studies related to pain modulation with an emphasis on factors such as age, neural development and pain measures. We critically discuss psychological mechanisms underlying placebo effects, including (1) verbally induced expectations, (2) conditioning and learning mechanisms, and (3) child-parent-physician interactions. Taken together, research suggests that placebo mechanisms can affect therapeutic outcomes and potentially be exploited clinically to improve clinical outcomes in pediatric population. Recommendations for further investigating the mechanistic bases and harnessing placebo effects for supportive therapeutic applications are given.

Placebo effects in children: a review

Of more than 155,000 PubMed citations found with the search term "placebo," only ~9,000 (5.8%) included the terms "children" or "adolescents." When all these papers were screened, only ~2,000 of them investigated the placebo effect per se, and of those, only ~50 (2.5%) discussed the placebo effect in children and adolescents. In this narrative review, we explore four aspects of the placebo response in children and adolescents: (i) the legal and ethical limitations and restrictions for the inclusion of children in clinical trials as well as in experimental (placebo) research that may explain the poor knowledge base; (ii) the question of whether or not the placebo effect is larger in children and adolescents as compared with adults; (iii) whether the mechanisms underlying the placebo effect are similar between children and adults; and (iv) whether mediators and moderators of the placebo effect are comparable between children and adults. We finally discuss some of the consequences from the current placebo research in adults that may affect both experimental and clinical research in children and adolescents.