Magnitude of the Placebo Response Across Treatment Modalities Used for Treatment-Resistant Depression in Adults: A Systematic Review and Meta-analysis

A narrative review of the placebo effect: historical roots, current applications, and emerging insights

PURPOSE

Placebo is a term to define physiologically inactive compounds used in treatment that causes physical and emotional changes. The placebo effect, driven by expectation and conditioning, plays a significant role in various conditions like pain, depression, and Parkinson's disease, while the nocebo effect can hinder treatment outcomes. Understanding mechanisms such as neuromodulation and genetics has gained importance in modern medicine. This review aims to explore the clinical relevance of placebo responses, particularly in neuropsychiatric disorders, and their potential in personalized medicine. By integrating placebo research into healthcare, it highlights opportunities to enhance treatment efficacy, improve patient well-being, and reduce reliance on pharmacological interventions.

METHODS

A comprehensive literature search was conducted in PubMed, Scopus, and Google Scholar databases. Recent studies were reviewed to evaluate placebo effects, and the variability of the placebo response in neuropsychiatric disorders was summarized.

RESULTS

Placebo effects significantly impact treatment outcomes across various conditions, including Parkinson's disease, depression, pain syndromes, and epilepsy. The mechanisms involve neurobiological and psychological factors, with evidence suggesting that placebo interventions can modulate neurotransmitter activity and improve patient well-being.

CONCLUSION

Integrating placebo research into clinical practice may enhance treatment outcomes, reduce drug dependency, and support personalized medicine by tailoring interventions to individual placebo responsiveness. Understanding placebo and nocebo mechanisms can optimize therapeutic strategies while minimizing unnecessary pharmacological treatments.

Oral esketamine for patients with severe treatment-resistant depression: Effectiveness, safety, and tolerability of a six-week open-label treatment program

BACKGROUND

Oral esketamine for patients with treatment-resistant depression (TRD) could offer certain advantages over other routes, such as intravenous or intranasal, but it has not been systematically studied in a real-world setting.

AIMS

Here we present results from a relatively large naturalistic study to evaluate the effectiveness, tolerability, and safety of oral esketamine in patients with TRD.

METHODS

One hundred eighty-five adults with severe TRD (average of 8.1 antidepressant trials plus electroconvulsive therapy in 63% without beneficial outcome) received oral esketamine treatment twice-weekly for 6 weeks with individually titrated doses ranging from 0.5 to 3 mg/kg. Outcome measures included change from baseline to week 6 on the Hamilton Depression Rating Scale (HDRS17), Minimal Clinically Important Difference (MCID), response, remission, self-reported symptom improvement, functioning, and side effects.

RESULTS

Oral esketamine treatment improved depressive symptom severity on the HDRS17 from 21.2 to 15.8 (p < 0.001). MCID, response, and remission rates were 47.1%, 26.8% and 15.6% respectively. In 45.9% of participants, treatment was continued after 6 weeks to maintain initial positive effects. Side effects were reported frequently but were overall well tolerated. The drop-out rate was 7.6%. We found no significant adverse effects associated with urinary tract or cognition.

CONCLUSIONS

Repeated treatment with oral esketamine is effective in improving depressive symptom severity in highly treatment-resistant depressive patients. It is safe, well tolerated, and patient-friendly. Considering the level of treatment resistance, outcomes were in the range of studies investigating other routes of (es)ketamine administration.

Specific symptomatology profile associated with treatment resistant depression: A multicentric study from the Group for the Study of Resistant Depression with a focus on sex

BACKGROUND

Clinical predictors of treatment-resistant depression could improve treatment strategies. Depressive symptom profiles at baseline are potential outcome predictors, but little evidence is available, and sex-specific profiles have been scarcely investigated.

METHODS

Baseline symptom scores of 1294 patients with major depressive disorder were assessed by the Montgomery-Åsberg depression rating scale (MADRS) as part of a multicenter study by the "Group for the Studies of Resistant Depression". Treatment outcomes were assessed according to the MADRS after ≥4 weeks of naturalistic treatment. We tested if individual MADRS item scores at baseline were associated with treatment outcome in the whole sample and in sex-stratified subgroups.

RESULTS

A specific baseline symptom profile was associated with non-response in the whole sample. In particular, apparent and reported sadness, reduced sleep, lassitude, inability to feel, and pessimistic thoughts were the only MADRS items that scored higher at baseline in patients with subsequent lack of response. In the sex-stratified analysis, females showed a similar profile overall, however they showed higher baseline levels of inner tension, inability to feel, and pessimistic thoughts compared to males, and these symptoms were associated with lack of response in females but not in males. Neurovegetative symptoms were poorly predictive. Overall baseline severity related to poor response.

LIMITATIONS

This is a post-hoc analysis. The naturalistic design of the study with a retrospective assessment is potential limitations.

CONCLUSION

A specific baseline symptom profile characterized by higher sadness, reduced sleep and anhedonic features may be indicative of poor treatment outcome. Females showed a distinctive baseline profile associated with poor response.

Opioids diminish the placebo antidepressant response: Observational post hoc findings from a randomized controlled ketamine trial

BACKGROUND

The endogenous opioid system is thought to play a role in the placebo antidepressant response. A recent trial comparing the rapid antidepressant effects of ketamine versus placebo in surgical patients, some of whom were on chronic opioid therapy, revealed a substantial placebo effect. This finding provided an opportunity to test the hypothesis that opioid agonist exposure interacts with placebo antidepressant responses.

METHODS

This post hoc analysis utilized data from a previously reported randomized, anesthesia-blinded, placebo-controlled trial of intravenous ketamine in depressed patients undergoing routine surgery. Mixed-effects models were used to determine whether baseline opioid use influenced antidepressant responses to the trial interventions, as measured by the Montgomery-Åsberg Depression Rating Scale (MADRS) over 1 to 14 days post-treatment.

RESULTS

The analysis showed that baseline opioid use significantly reduced post-treatment depression severity in patients who received placebo, but not in those who received ketamine. This reduction was independent of baseline depression severity, baseline pain intensity, and ethnicity. Additionally, there was negligible correlation between postoperative pain intensity and depression severity.

LIMITATIONS

This post hoc analysis was conducted on a small sample, and the findings need to be confirmed by prospective controlled studies.

CONCLUSIONS

Opioid use at baseline attenuated the placebo antidepressant response independently of pain in depressed patients who received the study treatment under general anesthesia for routine surgery. The antidepressant response was preserved in opioid users who received intravenous ketamine.

Functional connectivity subtypes during a positive mood induction: Predicting clinical response in a randomized controlled trial of ketamine for treatment-resistant depression

Ketamine has shown promise in rapidly improving symptoms of depression and most notably treatment-resistant depression (TRD). However, given the heterogeneity of TRD, biobehavioral markers of treatment response are necessary for the personalized prescription of intravenous ketamine. Heterogeneity in depression can be manifested in discrete patterns of functional connectivity (FC) in default mode, ventral affective, and cognitive control networks. This study employed a data-driven approach to parse FC during positive mood processing to characterize subgroups of patients with TRD prior to infusion and determine whether these connectivity-based subgroups could predict subsequent antidepressant response to ketamine compared to saline infusion. 152 adult patients with TRD completed a baseline assessment of FC during positive mood processing and were randomly assigned to either ketamine or saline infusion. The assessment utilized Subgroup-Group Iterative Multiple Model Estimation to recover directed connectivity maps and applied Walktrap algorithm to determine data-driven subgroups. Depression severity was assessed pre- and 24-hr postinfusion. Two connectivity-based subgroups were identified: Subgroup A (n = 110) and Subgroup B (n = 42). We observed that treatment response was moderated by an infusion type by subgroup interaction (p = .040). For patients receiving ketamine, subgroup did not predict treatment response (β = -.326, p = .499). However, subgroup predicted response for saline patients. Subgroup B individuals, relative to A, were more likely to be saline responders at 24-hr postinfusion (β = -2.146, p = .007). Thus, while ketamine improved depressive symptoms uniformly across both subgroups, this heterogeneity was a predictor of placebo response. (PsycInfo Database Record (c) 2025 APA, all rights reserved).

Infraslow Closed-Loop Brain Training for Anxiety and Depression (ISAD): A pilot randomised, sham-controlled trial in adult females with internalizing disorders

INTRODUCTION

The core resting-state networks (RSNs) have been shown to be dysfunctional in individuals with internalizing disorders (IDs; e.g., anxiety, depression). Source-localised, closed-loop brain training of infraslow (≤ 0.1 Hz) EEG signals may have the potential to reduce symptoms associated with IDs and restore normal core RSN function.

METHODS

We conducted a pilot randomized, double-blind, sham-controlled, parallel-group (3-arm) trial of infraslow neurofeedback (ISF-NFB) in adult females (n = 60) with IDs. Primary endpoints, which included the Hospital Anxiety and Depression Scale (HADS) and resting-state EEG activity and connectivity, were measured at baseline and post 6 sessions.

RESULTS

This study found credible evidence of strong nonspecific effects as evidenced by clinically important HADS score improvements (i.e., reductions) across groups. An absence of HADS score change differences between the sham and active groups indicated a lack of specific effects. Although there were credible slow (0.2-1.5 Hz) and delta (2-3.5 Hz) band activity reductions in the 1-region ISF-NFB group relative to sham within the targeted region of interest (i.e., posterior cingulate), differences in activity and connectivity modulation in the targeted frequency band of interest (i.e., ISFs = 0.01-0.1 Hz) were lacking between sham and active groups. Credible positive associations between changes in HADS depression scores and anterior cingulate cortex slow and delta activity also were found.

CONCLUSIONS

Short-term sham and genuine ISF-NFB resulted in rapid, clinically important improvements that were nonspecific in nature and possibly driven by placebo-related mechanisms. Future ISF-NFB trials should consider implementing design modifications that may better induce differential modulation of ISFs between sham and treatment groups, thereby enhancing the potential for specific clinical effects in ID populations.

TRIAL REGISTRATION

The trial was prospectively registered with the Australia New Zealand Clinical Trials Registry (ANZCTR; Trial ID: ACTRN12619001428156).

Lack of association between pretreatment glutamate/GABA and major depressive disorder treatment response

Studies have shown gamma-amino-butyric acid (GABA) and Glx (a combination of glutamate and glutamine) to be altered in major depressive disorder (MDD). Using proton Magnetic Resonance Spectroscopy (1H-MRS), this study aimed to determine whether lower pretreatment GABA and Glx levels in the medial frontal cortex, a region implicated in MDD pathophysiology, are associated with better antidepressant treatment response. Participants with MDD (N = 74) were antidepressant naïve or medication-free for at least three weeks before imaging. Two MEGA-PRESS 1H-MRS acquisitions were collected, interleaved with a water unsuppressed reference scan. GABA and Glx concentrations were quantified from an average difference spectrum, with preprocessing using Gannet and spectral fitting using TARQUIN. Following imaging, participants were randomized to escitalopram or placebo for 8 weeks in a double-blind design. Multivariable logistic regression models were applied with treatment type and age as covariates. Bayes Factor hypothesis testing was used to interpret the strength of the evidence. No significant association was found between pretreatment Glx, GABA, or Glx/GABA and depression remission status or the continuous outcome, percent change in symptom severity. In an exploratory analysis, no significant correlation was found between pretreatment Glx, GABA or Glx/GABA and days to response. Bayes factor analysis showed strong evidence towards the null hypotheses in all cases. To date, there are no replicated biomarkers in psychiatry. To address this, well-powered, placebo-controlled trials need to be undertaken and reported. The present analysis suggests pretreatment GABA, Glx, or their ratio cannot predict antidepressant treatment response. Future direction including examining glutamate and glutamine separately or examining biological subtypes of MDD separately.Trial Name: Advancing Personalized Antidepressant Treatment Using PET/MRI.Registration Number: NCT02623205 URL: https://clinicaltrials.gov/ct2/show/NCT02623205.

Emerging Medications for Treatment-Resistant Depression: A Review with Perspective on Mechanisms and Challenges

Background/Objectives: Non-response to initial treatment options for major depressive disorder (MDD) is a common clinical challenge with profound deleterious impacts for affected patients. Few treatments have received regulatory approval for treatment-resistant depression (TRD). Methods: A systematic search of United States and European Union clinical trials registries was conducted to identify Phase II, III, or IV clinical trials, with a last update posted on or after 1 January 2020, that were evaluating medications for TRD. For both the US and EU registries, the condition term "treatment resistant depression" and associated lower-level terms (per registry search protocol) were used. For the US registry, a secondary search using the condition term "depressive disorders" and the modifying term "inadequate" was also performed to capture registrations not tagged as TRD. Two additional searches were also conducted in the US registry for the terms "suicide" and "anhedonia" as transdiagnostic targets of investigational medications. Trials were categorized based on the primary mechanism of action of the trial's investigational medication. Results: Fifty clinical trials for TRD, 20 for anhedonia, and 25 for suicide were identified. Glutamate system modulation was the mechanism currently with the most compounds in development, including antagonists and allosteric modulators of NMDA receptors, AMPA receptors, metabotropic type 2/3 glutamate receptors, and intracellular effector molecules downstream of glutamate signaling. Psychedelics have seen the greatest surge among mechanistic targets in the past 5 years, however, with psilocybin in particular garnering significant attention. Other mechanisms included GABA modulators, monoamine modulators, anti-inflammatory/immune-modulating agents, and an orexin type 2 receptor antagonist. Conclusions: These investigations offer substantial promise for more efficacious and potentially personalized medication approaches for TRD. Challenges for detecting efficacy in TRD include the heterogeneity within the TRD population stemming from the presumed variety of biological dysfunctions underlying the disorder, comorbid disorders, chronic psychosocial stressors, and enduring effects of prior serotonergic antidepressant medication treatments.

Unilateral and bilateral theta burst stimulation for treatment-resistant depression: Follow up on a naturalistic observation study

OBJECTIVES

Theta burst stimulation (TBS) is a novel and faster modality of transcranial magnetic stimulation, which is showing promise as a treatment-resistant depression (TRD) treatment. Though TBS can be applied unilaterally or bilaterally, few studies have compared the effectiveness of both approaches in a naturalistic clinical sample. In this retrospective chart review, we aimed to: (1) replicate previous bilateral sequential TBS effectiveness in a larger cohort of patients at a single centre, (2) present treatment outcome data between unilateral and bilateral TBS approaches, (3) investigate baseline factors associated with our observed outcomes, and (4) examine the sustainability of response, with follow-up data up to 6 months from patients.

METHODS

We included 161 patients who received TBS (unilateral: n = 64 (40%), 45.55 ± 14.25 years old, 55% females; bilateral: n = 97 (60%), 47.67 ± 15.11 years old, 58% females).

RESULTS

Firstly, we observed 47% response and 34% remission in the bilateral group, replicating findings from a smaller naturalistic study from our group; patients receiving unilateral TBS displayed 36% response and 26% remission, with no significant differences found between unilateral and bilateral TBS in remission and response rates. Secondly, bilaterally stimulated patients needed fewer treatments than those stimulated unilaterally (27 vs 29 on average respectively, t [159] = 3.31, p = .001), and had significantly lower anxiety symptoms post treatment (GAD-7) relative to patients receiving unilateral stimulation, F (1,148) = 3.95, p = .049. Thirdly, no baseline factors were found to predict treatment outcomes. Lastly, after six months, 69% of patients who met the response criteria did not require additional treatment or a change in medication.

CONCLUSIONS

Our findings support the efficacy and tolerability of TBS in TRD and indicate that bilateral TBS may have a superior anxiolytic effect and offer a slightly faster time to response.

Placebo effects in randomized trials of pharmacological and neurostimulation interventions for mental disorders: An umbrella review

There is a growing literature exploring the placebo response within specific mental disorders, but no overarching quantitative synthesis of this research has analyzed evidence across mental disorders. We carried out an umbrella review of meta-analyses of randomized controlled trials (RCTs) of biological treatments (pharmacotherapy or neurostimulation) for mental disorders. We explored whether placebo effect size differs across distinct disorders, and the correlates of increased placebo effects. Based on a pre-registered protocol, we searched Medline, PsycInfo, EMBASE, and Web of Knowledge up to 23.10.2022 for systematic reviews and/or meta-analyses reporting placebo effect sizes in psychopharmacological or neurostimulation RCTs. Twenty meta-analyses, summarising 1,691 RCTs involving 261,730 patients, were included. Placebo effect size varied, and was large in alcohol use disorder (g = 0.90, 95% CI [0.70, 1.09]), depression (g = 1.10, 95% CI [1.06, 1.15]), restless legs syndrome (g = 1.41, 95% CI [1.25, 1.56]), and generalized anxiety disorder (d = 1.85, 95% CI [1.61, 2.09]). Placebo effect size was small-to-medium in obsessive-compulsive disorder (d = 0.32, 95% CI [0.22, 0.41]), primary insomnia (g = 0.35, 95% CI [0.28, 0.42]), and schizophrenia spectrum disorders (standardized mean change = 0.33, 95% CI [0.22, 0.44]). Correlates of larger placebo response in multiple mental disorders included later publication year (opposite finding for ADHD), younger age, more trial sites, larger sample size, increased baseline severity, and larger active treatment effect size. Most (18 of 20) meta-analyses were judged 'low' quality as per AMSTAR-2. Placebo effect sizes varied substantially across mental disorders. Future research should explore the sources of this variation. We identified important gaps in the literature, with no eligible systematic reviews/meta-analyses of placebo response in stress-related disorders, eating disorders, behavioural addictions, or bipolar mania.

Placebo and nocebo effects in gambling disorder pharmacological trials: a meta-analysis

BACKGROUND

Placebo and nocebo effects are widely reported across psychiatric conditions, yet have seldom been examined in the context of gambling disorder. Through meta-analysis, we examined placebo effects, their moderating factors, and nocebo effects, from available randomised, controlled pharmacological clinical trials in gambling disorder.

METHODS

We searched, up to 19 February 2024, a broad range of databases, for double-blind randomised controlled trials (RCTs) of medications for gambling disorder. Outcomes were gambling symptom severity and quality of life (for efficacy), and drop outs due to medication side effects in the placebo arms.

RESULTS

We included 16 RCTs (n = 833) in the meta-analysis. The overall effect size for gambling severity reduction in the placebo arms was 1.18 (95%CI 0.91-1.46) and for quality of life improvement was 0.63 (0.42-0.83). Medication class, study sponsorship, trial duration, baseline severity of gambling and publication year significantly moderated effect sizes for at least some of these outcome measures. Author conflict of interest, placebo run-in, gender split, severity scale choice, age of participants or unbalanced randomisation did not moderate effect sizes. Nocebo effects leading to drop out from the trial were observed in 6% of participants in trials involving antipsychotics, while this was less for other medication types.

CONCLUSION

Placebo effects in trials of pharmacological treatment of gambling disorder are large, and there are several moderators of this effect. Nocebo effects were measureable and may be influenced by medication class being studied. Practical implications of these new findings for the field are discussed, along with recommendations for future clinical trials.

S. Sanches P, P. Silva D, Torres ILS, Fregni F, Caumo W. Modulation of neural networks and symptom correlated in fibromyalgia: A randomized double-blind multi-group explanatory clinical trial of home-based transcranial direct current stimulation

BACKGROUND

Transcranial direct current stimulation (tDCS) might modulate neural activity and promote neural plasticity in patients with fibromyalgia (FM). This multi-group randomized clinical trial compared home-based active tDCS (HB-a-tDCS) on the left dorsolateral prefrontal cortex (l-DLPFC) or home-based sham tDCS (HB-s-tDCS), and HB-a-tDCS or HB-s-tDCS on the primary motor cortex (M1) in the connectivity analyses in eight regions of interest (ROIs) across eight resting-state electroencephalography (EEG) frequencies.

METHODS

We included 48 women with FM, aged 30 to 65, randomly assigned to 2:1:2:1 to receive 20 sessions during 20 minutes of HB-a-tDCS 2mA or HB-s-tDCS, over l-DLPFC or M1, respectively. EEG recordings were obtained before and after treatment with eyes open (EO) and eyes closed (EC).

RESULTS

In the EC condition, comparing pre to post-treatment, the HB-a-tDCS on l-DLPFC decreased the lagged coherence connectivity in the delta frequency band between the right insula and left anterior cingulate cortex (ACC) (t = -3.542, p = .048). The l-DLPFC HB-a-tDCS compared to HB-s-tDCS decreased the lagged coherence connectivity in the delta frequency band between the right insula and left ACC (t = -4.000, p = .017). In the EO condition, the l-DLPFC HB-a-tDCS compared to M1 HB-s-tDCS increased the lagged coherence connectivity between the l-DLPFC and left ACC in the theta band (t = -4.059, p = .048). Regression analysis demonstrated that the HB-a-tDCS effect on the l-DLPFC was positively correlated with sleep quality. On the other hand, the HB-a-tDCS on l-DLPFC and HB-s-tDCS on M1 were positively correlated with pain catastrophizing.

CONCLUSIONS

These results show that HB-a-tDCS affects the neural connectivity between parts of the brain that control pain's emotional and attentional aspects, which are most noticeable at lower EEG frequencies in a rest state. This effect on neural oscillations could serve as a neural marker associated with its efficacy in alleviating fibromyalgia symptoms.

CLINICAL TRIAL REGISTRATION

identifier [NCT03843203].

Masking Influences: A Systematic Review of Placebo Control and Masking in Psychedelic Studies

Psychedelic-assisted therapy is becoming increasingly acknowledged as an effective therapeutic intervention for various psychiatric illnesses. However, the evaluation of masking success is rarely reported in trials. The objective of the present systematic review was to evaluate placebo-control and masking in studies exploring psychedelic-assisted therapy. Nine (k = 9) studies dating between January 2010 and March 2023 were retrieved using six databases, following strict inclusion and exclusion criteria. The results show that almost 78% of the studies had, at best, "poor" masking success. At the same time, 60% of active placebo and 75% of inactive placebo studies showed large effect sizes. In other words, masking influences, including benign unmasking, cannot be excluded. We therefore conclude that efficacy of psilocybin, Ayahuasca, or LSD is only one of the possible interpretations of large, positive changes in symptomatology for patients suffering from, for example, alcohol use disorder, anxiety with or without life-threatening disease, anxiety and/or depression with life-threatening cancer, treatment-resistant depression or major depressive disorder. We recommend care be taken to increase successful masking procedures and discuss alternative treatment designs to better control for potential masking influences.

Opioids Diminish the Placebo Antidepressant Response: A Post Hoc Analysis of a Randomized Controlled Ketamine Trial

Background

The endogenous opioid system is thought to play a role in the placebo antidepressant response. A recent trial comparing the rapid antidepressant effects of ketamine versus placebo in surgical patients, some of whom were on chronic opioid therapy, revealed a substantial placebo effect. This finding provided an opportunity to test the hypothesis that opioid agonist exposure interacts with placebo antidepressant responses.

Methods

This post hoc analysis utilized data from a previously reported randomized, anesthesia-blinded, placebo-controlled trial of intravenous ketamine in depressed patients undergoing routine surgery. Mixed-effects models were used to determine whether baseline opioid use influenced antidepressant responses to the trial interventions, as measured by the Montgomery-Åsberg Depression Rating Scale (MADRS) over 1 to 14 days post-treatment.

Results

In the placebo arm, baseline opioid use was associated with a 10-point increase (95% CI: 0.81-19.4) in MADRS scores across all post-treatment time points, indicating worse depression in this subgroup. In an alternative model using percent change in MADRS scores, the difference between opioid users and non-users was 38.4% (95% CI: 8.59-68.2), with opioid users experiencing less improvement. For ketamine-treated participants, baseline opioid use did not significantly impact MADRS scores or the percent change in MADRS scores. Pain intensity was not a significant predictor of MADRS outcomes, and the correlation between post-treatment MADRS scores and pain intensity was negligible (R=0.12).

Limitations

This analysis was unregistered and conducted on a small sample; the findings need to be confirmed by prospective controlled studies.

Conclusions

Opioid use at baseline attenuated the placebo antidepressant response independently of pain in depressed patients who received the study treatment under general anesthesia for routine surgery. The antidepressant response was preserved in opioid users who received intravenous ketamine.

Breakthroughs and challenges for generating brain network-based biomarkers of treatment response in depression

Treatment outcomes widely vary for individuals diagnosed with major depressive disorder, implicating a need for deeper understanding of the biological mechanisms conferring a greater likelihood of response to a particular treatment. Our improved understanding of intrinsic brain networks underlying depression psychopathology via magnetic resonance imaging and other neuroimaging modalities has helped reveal novel and potentially clinically meaningful biological markers of response. And while we have made considerable progress in identifying such biomarkers over the last decade, particularly with larger, multisite trials, there are significant methodological and practical obstacles that need to be overcome to translate these markers into the clinic. The aim of this review is to review current literature on brain network structural and functional biomarkers of treatment response or selection in depression, with a specific focus on recent large, multisite trials reporting predictive accuracy of candidate biomarkers. Regarding pharmaco- and psychotherapy, we discuss candidate biomarkers, reporting that while we have identified candidate biomarkers of response to a single intervention, we need more trials that distinguish biomarkers between first-line treatments. Further, we discuss the ways prognostic neuroimaging may help to improve treatment outcomes to neuromodulation-based therapies, such as transcranial magnetic stimulation and deep brain stimulation. Lastly, we highlight obstacles and technical developments that may help to address the knowledge gaps in this area of research. Ultimately, integrating neuroimaging-derived biomarkers into clinical practice holds promise for enhancing treatment outcomes and advancing precision psychiatry strategies for depression management. By elucidating the neural predictors of treatment response and selection, we can move towards more individualized and effective depression interventions, ultimately improving patient outcomes and quality of life.

The impact of cannabidiol placebo on amygdala-based neural responses to an acute stressor

BACKGROUND

Cannabidiol (CBD) impacts brain regions implicated in anxiety reactivity and stress reactivity (e.g., amygdala, anterior cingulate cortex (ACC), anterior insula (AI)); however, placebo-controlled studies are mixed regarding CBD's anxiolytic effects. We previously reported that CBD expectancy alone can alter subjective, physiological, and endocrine markers of stress/anxiety; however, it is unclear whether these findings reflect altered brain reactivity. This study evaluated whether CBD expectancy independently alters amygdala resting-state functional connectivity (rsFC) with the ACC and AI following acute stress.

METHOD

Thirty-eight (20 females) healthy adults were randomly assigned to receive accurate or inaccurate information regarding the CBD content of a CBD-free oil administered during a single experimental session. Following a baseline resting state MRI scan, participants administered their assigned oil sublingually, engaged in a stress task (serial subtraction with negative feedback) inside the scanner, and underwent another resting state MRI scan. Amygdala rsFC with the ACC and AI was measured during each scan, and the subjective state was assessed at six time points. Outcomes were analyzed using ANCOVA.

RESULTS

CBD expectancy (vs CBD-free expectancy) was associated with significantly weaker rsFC between the left amygdala and right ACC (p = 0.042), but did not systematically alter amygdala-AI rsFC (p-values > 0.05). We also replicated our previously reported CBD expectancy effects on subjective stress/anxiety in the scanner context.

CONCLUSION

CBD placebo effects may be sufficient to alter neural responses relevant to its purported anxiolytic and stress-relieving properties. Future work is needed to replicate these results and determine whether CBD expectancy and pharmacology interact to alter neural anxiety reactivity and stress reactivity.

Efficacy of a Standalone Smartphone Application to Treat Postnatal Depression: A Randomized Controlled Trial

INTRODUCTION

Smartphone app interventions based on cognitive-behavioral therapy (CBT) are promising scalable alternatives for treating mental disorders, but the evidence of their efficacy for postpartum depression is limited. We assessed the efficacy of Motherly, a standalone CBT-based smartphone app, in reducing symptoms of postpartum depression.

METHODS

Women aged 18-40 with symptoms of postpartum depression were randomized either to intervention (Motherly app) or active control (COMVC app). The primary outcome was symptoms of depression measured by the Edinburgh Postnatal Depression Scale (EPDS) at post-treatment. Secondary outcomes were anxiety symptoms, parental stress, quality of sleep, behavioral activation, availability of response-contingent positive reinforcement, and clinical improvement at post-treatment and 1-month follow-up. Exploratory analyses were performed to investigate if app engagement was associated with treatment response.

RESULTS

From November 2021 to August 2022, 1,751 women volunteered, of which 264 were randomized, and 215 provided primary outcome data. No statistically significant differences were found between groups at post-treatment: intervention: mean (SD): 12.75 (5.52); active control: 13.28 (5.32); p = 0.604. There was a statistically significant effect of the intervention on some of the secondary outcomes. Exploratory analyses suggest a dose-response relationship between Motherly app engagement and outcomes.

CONCLUSION

Our standalone app intervention did not significantly reduce postnatal depression symptoms when compared to active control. Exploratory findings suggest that negative findings might be associated with insufficient app engagement. Consistent with current literature, our findings suggest that standalone app interventions for postpartum depression are not ready to be implemented in clinical practice.

Cariprazine in the acute treatment of unipolar and bipolar depression: A systematic review and meta-analysis

BACKGROUND

Cariprazine has emerged as a promising augmenting treatment agent for unipolar depression and as a monotherapy option for bipolar depression. We evaluated cariprazine's efficacy in treating acute major depressive episodes in individuals with major depressive disorder (MDD) or bipolar disorder.

METHODS

A systematic review was conducted on MEDLINE, Embase, PsycINFO, Scopus and Web of Science, ClinicalTrials.gov and ScanMedicine. Study quality was assessed using the RoB 2 tool. Pairwise and dose-response meta-analyses were conducted with RStudio. Evidence quality was assessed with GRADE.

RESULTS

Nine RCTs meeting inclusion criteria encompassed 4889 participants. Cariprazine, compared to placebo, significantly reduced the MADRS score (MD = -1.49, 95 % CI: -2.22 to -0.76) and demonstrated significantly higher response (RR = 1.21, 95 % CI: 1.12 to 1.30) and remission (RR = 1.19, 95 % CI: 1.06 to 1.34) rates. Subgroup analysis unveiled statistically significant reductions in MADRS score in MDD (MD = -1.15, 95 % CI: -2.04 to -0.26) and bipolar I disorder (BDI) (MD = -2.53, 95 % CI: -3.61 to -1.45), higher response rates for both MDD (RR = 1.19, 95 % CI: 1.08 to 1.31) and BDI (RR = 1.27, 95 % CI: 1.10 to 1.46), and higher remission rates only for BDI (RR = 1.41, 95 % CI: 1.24 to 1.60). A higher rate of treatment discontinuation due to adverse events was observed.

LIMITATIONS

Reliance solely on RCTs limits generalisability; strict criteria might not reflect real-world diversity.

CONCLUSIONS

Cariprazine demonstrates efficacy in treating major depressive episodes, although variations exist between MDD and BDI and tolerability may be an issue.

Probiotics and magnesium orotate for the treatment of major depressive disorder: a randomised double blind controlled trial

Following on from our pilot studies, this study aimed to test the efficacy of a combination of probiotics (Lactobacillus acidophilus, Bifidobacterium bifidum, Streptococcus thermophilus), magnesium orotate and coenzyme 10 for the treatment of major depressive disorder (MDD) through a double-blind placebo controlled clinical trial. The participants were 120 adults diagnosed with MDD randomised to daily oral administration, over 8 weeks, of either the intervention or placebo, with a 16-week follow-up period. Intent-to-treat analysis found a significantly lower frequency of the presence of a major depressive episode in the intervention group compared with placebo at the end of the 8-week treatment phase, with no difference between the two conditions at 8-week follow-up. Both the categorical and continuous measure of depressive symptoms showed a significant difference between the two conditions at 4 weeks, but not 8 and 16 weeks. The secondary end-point was demonstrated with an overall reduction in self-rated symptoms of anxiety and stress in the active treatment group compared with placebo. These findings suggest that the combination of probiotics, magnesium orotate and coenzyme 10 may be an effective treatment of MDD over an 8-week period.

Gut-Brain Axis: Role of Microbiome, Metabolomics, Hormones, and Stress in Mental Health Disorders

The influence of gut microbiome, metabolites, omics, hormones, and stress on general and mental health is increasingly being recognized. Ancient cultures recognized the importance of diet and gut health on the overall health of an individual. Western science and modern scientific methods are beginning to unravel the foundations and mechanisms behind some of the ancient beliefs and customs. The gut microbiome, an organ itself, is now thought to influence almost all other organs, ranging from the brain to the reproductive systems. Gut microbiome, metabolites, hormones, and biological sex also influence a myriad of health conditions that range from mental health disorders, obesity, gastrointestinal disorders, and cardiovascular diseases to reproductive health. Here, we review the history and current understanding of the gut-brain axis bidirectional talk in various mental health disorders with special emphasis on anxiety and depressive disorders, whose prevalence has increased by over 50% in the past three decades with COVID-19 pandemic being the biggest risk factor in the last few years. The vagal nerve is an important contributor to this bidirectional talk, but other pathways also contribute, and most remain understudied. Probiotics containing Lactobacillus and Bifidobacterium species seem to have the most impact on improvement in mental health symptoms, but the challenge appears to be maintaining sustained levels, especially since neither Lactobacillus nor Bifidobacterium can permanently colonize the gut. Ancient endogenous retroviral DNA in the human genome is also linked to several psychiatric disorders, including depression. These discoveries reveal the complex and intricately intertwined nature of gut health with mental health disorders.

Differential Outcomes of Placebo Treatment Across 9 Psychiatric Disorders: A Systematic Review and Meta-Analysis

Importance

Placebo is the only substance systematically evaluated across common psychiatric diagnoses, but comprehensive cross-diagnostic comparisons are lacking.

Objective

To compare changes in placebo groups in recent high-quality randomized clinical trials (RCTs) across a broad spectrum of psychiatric disorders in adult patients.

Data Sources

MEDLINE and the Cochrane Database of Systematic Reviews were systematically searched in March 2022 for the latest systematic reviews meeting predetermined high-quality criteria for 9 major psychiatric diagnoses.

Study Selection

Using these reviews, the top 10 highest-quality (ie, lowest risk of bias, according to the Cochrane Risk of Bias tool) and most recent placebo-controlled RCTs per diagnosis (totaling 90 RCTs) were selected, adhering to predetermined inclusion and exclusion criteria.

Data Extraction and Synthesis

Following the Cochrane Handbook, 2 authors independently carried out the study search, selection, and data extraction. Cross-diagnosis comparisons were based on standardized pre-post effect sizes (mean change divided by its SD) for each placebo group. This study is reported following the Meta-analysis of Observational Studies in Epidemiology (MOOSE) reporting guideline.

Main Outcome and Measure

The primary outcome, pooled pre-post placebo effect sizes (dav) with 95% CIs per diagnosis, was determined using random-effects meta-analyses. A Q test assessed statistical significance of differences across diagnoses. Heterogeneity and small-study effects were evaluated as appropriate.

Results

A total of 90 RCTs with 9985 placebo-treated participants were included. Symptom severity improved with placebo in all diagnoses. Pooled pre-post placebo effect sizes differed across diagnoses (Q = 88.5; df = 8; P < .001), with major depressive disorder (dav = 1.40; 95% CI, 1.24-1.56) and generalized anxiety disorder (dav = 1.23; 95% CI, 1.06-1.41) exhibiting the largest dav. Panic disorder, attention-deficit/hyperactivity disorder, posttraumatic stress disorder, social phobia, and mania showed dav between 0.68 and 0.92, followed by OCD (dav = 0.65; 95% CI, 0.51-0.78) and schizophrenia (dav = 0.59; 95% CI, 0.41-0.76).

Conclusion and Relevance

This systematic review and meta-analysis found that symptom improvement with placebo treatment was substantial in all conditions but varied across the 9 included diagnoses. These findings may help in assessing the necessity and ethical justification of placebo controls, in evaluating treatment effects in uncontrolled studies, and in guiding patients in treatment decisions. These findings likely encompass the true placebo effect, natural disease course, and nonspecific effects.

Engaging Mood Brain Circuits with Psilocybin (EMBRACE): a study protocol for a randomized, placebo-controlled and delayed-start, neuroimaging trial in depression

BACKGROUND

Major depressive disorder (MDD) is a leading cause of disability worldwide across domains of health and cognition, affecting overall quality of life. Approximately one third of individuals with depression do not fully respond to treatments (e.g., conventional antidepressants, psychotherapy) and alternative strategies are needed. Recent early phase trials suggest psilocybin may be a safe and efficacious intervention with rapid-acting antidepressant properties. Psilocybin is thought to exert therapeutic benefits by altering brain network connectivity and inducing neuroplastic changes that endure for weeks post-treatment. Although early clinical results are encouraging, psilocybin's acute neurobiological effects on neuroplasticity have not been fully investigated. We aim to examine for the first time how psilocybin acutely (intraday) and subacutely (weeks) alters functional brain networks implicated in depression.

METHODS

Fifty participants diagnosed with MDD or persistent depressive disorder (PDD) will be recruited from a tertiary mood disorders clinic and undergo 1:1 randomization into either an experimental or control arm. Participants will be given either 25 mg psilocybin or 25 mg microcrystalline cellulose (MCC) placebo for the first treatment. Three weeks later, those in the control arm will transition to receiving 25 mg psilocybin. We will investigate whether treatments are associated with changes in arterial spin labelling and blood oxygenation level-dependent contrast neuroimaging assessments at acute and subacute timepoints. Primary outcomes include testing whether psilocybin demonstrates acute changes in (1) cerebral blood flow and (2) functional brain activity in networks associated with mood regulation and depression when compared to placebo, along with changes in MADRS score over time compared to placebo. Secondary outcomes include changes across complementary clinical psychiatric, cognitive, and functional scales from baseline to final follow-up. Serum peripheral neurotrophic and inflammatory biomarkers will be collected at baseline and follow-up to examine relationships with clinical response, and neuroimaging measures.

DISCUSSION

This study will investigate the acute and additive subacute neuroplastic effects of psilocybin on brain networks affected by depression using advanced serial neuroimaging methods. Results will improve our understanding of psilocybin's antidepressant mechanisms versus placebo response and whether biological measures of brain function can provide early predictors of treatment response.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT06072898. Registered on 6 October 2023.

Treatment expectations and clinical outcomes following repetitive transcranial magnetic stimulation for treatment-resistant depression

BACKGROUND

Patient expectations, including both positive (placebo) and negative (nocebo) effects, influence treatment outcomes, yet their impact on acute repetitive transcranial magnetic stimulation (rTMS) for treatment-resistant depression (TRD) is unclear.

METHODS

In this single-center retrospective chart review, 208 TRD patients completed the Stanford Expectation of Treatment Scale (SETS) before starting open-label rTMS treatment. Patients were offered two excitatory rTMS protocols (deep TMS or intermittent theta-burst stimulation), which stimulated the left dorsolateral prefrontal cortex. A minimum of 20 once daily treatments were provided, delivered over 4-6 weeks. Primary outcomes were 1) remission, measured by a post-treatment score of <8 on the Hamilton Depression Rating Scale (HAMD-17), and 2) premature discontinuation. The change in HAMD-17 scores over time was used as a secondary outcome. Physicians were blinded to SETS scores. Logistic and linear regression, adjusting for covariates, assessed SETS and HAMD-17 relationships.

RESULTS

Of 208 patients, 177 had baseline and covariate data available. The mean positivity bias score (positive expectancy minus negative expectancy subscale averages) was 0.48 ± 2.21, indicating the cohort was neutral regarding the expectations of their treatment on average. Higher positive expectancy scores were significantly associated with greater odds of remission (OR = 1.90, p = 0.003) and greater reduction in HAMD-17 scores (β = 1.30, p = 0.005) at the end of acute treatment, after adjusting for covariates. Negative expectancy was not associated with decreased odds of remission (p = 0.2) or treatment discontinuation (p = 0.8).

CONCLUSIONS

Higher pre-treatment positive expectations were associated with greater remission rates with open-label rTMS in a naturalistic cohort of patients with TRD.

Deep Brain Stimulation of the Medial Forebrain Bundle for Treatment-Resistant Depression: A Systematic Review Focused on the Long-Term Antidepressive Effect

OBJECTIVE

Major depression affects millions of people worldwide and has important social and economic consequences. Since up to 30% of patients do not respond to several lines of antidepressive drugs, deep brain stimulation (DBS) has been evaluated for the management of treatment-resistant depression (TRD). The superolateral branch of the medial forebrain bundle (slMFB) appears as a "hypothesis-driven target" because of its role in the reward-seeking system, which is dysfunctional in depression. Although initial results of slMFB-DBS from open-label studies were promising and characterized by a rapid clinical response, long-term outcomes of neurostimulation for TRD deserve particular attention. Therefore, we performed a systematic review focused on the long-term outcome of slMFB-DBS.

MATERIALS AND METHODS

A literature search using Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria was conducted to identify all studies reporting changes in depression scores after one-year follow-up and beyond. Patient, disease, surgical, and outcome data were extracted for statistical analysis. The Montgomery-Åsberg Depression Rating Scale (ΔMADRS) was used as the clinical outcome, defined as percentage reduction from baseline to follow-up evaluation. Responders' and remitters' rates were also calculated.

RESULTS

From 56 studies screened for review, six studies comprising 34 patients met the inclusion criteria and were analyzed. After one year of active stimulation, ΔMADRS was 60.7% ± 4%; responders' and remitters' rates were 83.8% and 61.5%, respectively. At the last follow-up, four to five years after the implantation, ΔMADRS reached 74.7% ± 4.6%. The most common side effects were stimulation related and reversible with parameter adjustments.

CONCLUSIONS

slMFB-DBS appears to have a strong antidepressive effect that increases over the years. Nevertheless, to date, the overall number of patients receiving implantations is limited, and the slMFB-DBS surgical technique seems to have an important impact on the clinical outcome. Further multicentric studies in a larger population are needed to confirm slMFB-DBS clinical outcomes.

A biphasic response to blueberry supplementation on depressive symptoms in emerging adults: a double-blind randomized controlled trial

PURPOSE

The aim of the present study was to examine the acute and chronic effects of wild blueberry supplementation on mood, executive function, and serum biomarkers of neuroplasticity, inflammation, and oxidative stress in emerging adults with moderate-to-severe depressive symptoms.

METHODS

In this double-blind trial, 60 emerging adults (Mage = 20.0 years, 32% male) with self-reported depressive symptoms were randomly assigned to receive a single blueberry drink (acute phase), followed by 6 weeks of daily blueberry supplementation (chronic phase), or a matched placebo drink. The primary outcome was Beck Depression Inventory-II (BDI-II) scores at 6-week follow-up. Further measures included momentary affect (PANAS-X) and accuracy on an executive function task. The data were analyzed using ANCOVAs adjusted for baseline values, sex, and habitual fruit and vegetable intake. Estimated marginal means were calculated to compare the treatment arms.

RESULTS

The blueberry drink significantly improved positive affect (p = 0.026) and executive function (p = 0.025) at 2 h post-ingestion, with change scores being positively correlated in the blueberry group (r = 0.424, p = 0.017). However, after six weeks of supplementation the reduction in BDI-II scores was greater in the placebo group by 5.8 points (95% CI: 0.8-10.7, p = 0.023). Generalized anxiety and anhedonia also decreased significantly more in the placebo group. No significant differences were found for any of the biomarkers.

CONCLUSIONS

Six weeks of wild blueberry supplementation were inferior to placebo in reducing depressive symptoms. Nevertheless, the correlated improvements in positive affect and executive function after a single dose of blueberries point to a beneficial, albeit transient, psychological effect. These contrasting results suggest a biphasic, hormetic-like response that warrants further investigation.

TRIAL REGISTRATION

NCT04647019, dated 30 November, 2020.

Evaluating the efficacy and mechanisms of a ketogenic diet as adjunctive treatment for people with treatment-resistant depression: A protocol for a randomised controlled trial

BACKGROUND

One-third of people with depression do not respond to antidepressants, and, after two adequate courses of antidepressants, are classified as having treatment-resistant depression (TRD). Some case reports suggest that ketogenic diets (KDs) may improve some mental illnesses, and preclinical data indicate that KDs can influence brain reward signalling, anhedonia, cortisol, and gut microbiome which are associated with depression. To date, no trials have examined the clinical effect of a KD on TRD.

METHODS

This is a proof-of-concept randomised controlled trial to investigate the efficacy of a six-week programme of weekly dietitian counselling plus provision of KD meals, compared with an intervention involving similar dietetic contact time and promoting a healthy diet with increased vegetable consumption and reduction in saturated fat, plus food vouchers to purchase healthier items. At 12 weeks we will assess whether participants have continued to follow the assigned diet. The primary outcome is the difference between groups in the change in Patient Health Questionnaire-9 (PHQ-9) score from baseline to 6 weeks. PHQ-9 will be measured at weeks 2, 4, 6 and 12. The secondary outcomes are the differences between groups in the change in remission of depression, change in anxiety score, functioning ability, quality of life, cognitive performance, reward sensitivity, and anhedonia from baseline to 6 and 12 weeks. We will also assess whether changes in reward sensitivity, anhedonia, cortisol awakening response and gut microbiome may explain any changes in depression severity.

DISCUSSION

This study will test whether a ketogenic diet is an effective intervention to reduce the severity of depression, anxiety and improve quality of life and functioning ability for people with treatment-resistant depression.

Biosemiotic medicines: Symbolic formulations for placebo enhancements

The healing response is a complex and multiform procedure that involves many physical and symbolic interactions and synchronizations. In the clinical research model, certain factors are abstracted during which contextual elements, such as placebo responses and communicative factors, are excluded to reveal the pieces of evidence that are necessary for the mass production of clinical materials and methods. On the other side, clinical practice is a singular and chaotic communicative action in which we should include contextual and discursive factors for prompting proper biological as well as behavioral responses. Placebo responses, personal history and attitudes, and clinical relationships and communication are some of the contextual and individual factors that can be changed effectively if we can communicate with the symbolic and reflective matrices of clinical practice. In this article, the author introduces a biosemiotic formula for healing responses that include symbolic and reflective factors of healing response aligned with the related biological procedures. Not only are psychological interventions beneficial in mental health problems and symptom control but they could also be used as co-treatments to reinforce placebo responses and improve illness behavior and treatment narratives.

Potential impact of unblinding on observed treatment effects in Alzheimer's disease trials

INTRODUCTION

Adverse effects of monoclonal antibodies against amyloid beta are common, and may affect validity of randomized controlled trials (RCTs) through unblinding of participants.

METHODS

We used observations from published phase 3 RCTs in Alzheimer's disease to calculate the magnitude of unblinding effects on cognition that would be required to explain observed cognitive benefits in RCTs.

RESULTS

In trials of lecanemab, aducanumab, and donanemab, incidence of amyloid-related imaging abnormalities with active treatment ranged from 22% to 44%, the vast majority of which presumably led to unblinding. Effects of unblinding on the Clinical Dementia Rating Sum of Boxes required to fully explain observed drug effects ranged from 1.1 point (95% confidence interval: 0.2-2.0) with aducanumab, to 3.3 points (2.1-4.4) with donanemab and 3.7 points (2.0-5.6) with lecanemab. Infusion-related reactions were common, with potential unblinding effects particularly for lecanemab. Similar patterns were observed for the Alzheimer's Disease Assessment Scale Cognitive subscale.

DISCUSSION

Psychological treatment effects due to unblinding may explain a substantial share of observed treatment effects in RCTs.

Hype or hope? High placebo response in major depression treatment with ketamine and esketamine: a systematic review and meta-analysis

Background

Ketamine and esketamine offer a novel approach in the pharmacological treatment of major depressive disorder (MDD). This meta-analysis aimed to investigate the placebo response in double-blind, randomized controlled studies (RCTs) on patients with MDD receiving ketamine or esketamine.

Methods

For this systematic review and meta-analysis Medline (PubMed), Cochrane Central Register of Controlled Trials (CENTRAL), PsycInfo and Embase databases were systematically searched for citations published up to March 17, 2023. A total number of 5017 abstracts was identified. Quality of the included trials was assessed with the Cochrane risk-of-bias tool. The meta-analysis was performed using a restricted maximum likelihood model. This study is registered with PROSPERO, number CRD42022377591.

Results

A total number of 14 studies and 1100 participants (593 in the medication group and 507 in the placebo group) meeting the inclusion criteria were selected. We estimated the pooled effect sizes of the overall placebo (d pl = -1.85 [CI 95%: -2.9 to -0.79] and overall treatment (dtr = -2.57; [CI 95% -3.36 to -1.78]) response. The overall placebo response accounts for up to 72% of the overall treatment response. Furthermore, we performed subgroup analysis of 8 studies for the for the 7 days post-intervention timepoint. Seven days post-intervention the placebo response (d pl 7d = -1.98 [CI 95%: -3.26 to -0.69]) accounts for 66% of the treatment response (d tr 7d = - 3.01 [CI 95%, -4.28 to -1.74]).

Conclusion

Ketamine and esketamine show large antidepressant effects. However, our findings suggest that the placebo response plays a significant role in the antidepressant response and should be used for the benefit of the patients in clinical practice.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42022377591.

Impact of multiple-session home-based transcranial direct current stimulation (M-HB-tDCS) on eating behavior in fibromyalgia: A factorial randomized clinical trial

BACKGROUND

Multiple-session home-based self-applied transcranial direct current stimulation (M-HB-self-applied-tDCS) has previously been found to effectively reduce chronic pain and enhance cognitive function. However, the effectiveness of this method for disordered eating behavior still needs to be studied.

OBJECTIVE

This study aimed to assess whether 20 sessions of M-HB-self-applied-tDCS, administered over four weeks to either the left dorsolateral prefrontal cortex (L-DLPFC) or primary motor cortex (M1), could improve various aspects of eating behavior, anthropometric measures, and adherence.

METHODS

We randomly assigned 102 fibromyalgia patients between the ages of 30 and 65 to one of four tDCS groups: L-DLPFC (anodal-(a)-tDCS, n = 34; sham-(s)-tDCS, n = 17) or M1 (a-tDCS, n = 34; s-tDCS, n = 17). Patients self-administered 20-min tDCS sessions daily with 2 mA under remote supervision following in-person training.

RESULTS

Generalized linear models revealed significant effects of M-HB-self-applied-tDCS compared to s-tDCS on uncontrolled eating (UE) (Wald χ2 = 5.62; df = 1; P = 0.018; effect size, ES = 0.55), and food craving (Wald χ2 = 5.62; df = 1; P = 0.018; ES = 0.57). Regarding fibromyalgia symptoms, we found a differentiated impact of a-tDCS on M1 compared to DLPFC in reducing food cravings. Additionally, M-HB-a-tDCS significantly reduced emotional eating and waist size. In contrast, M1 stimulation was more effective in improving fibromyalgia symptoms. The global adherence rate was high, at 88.94%.

CONCLUSION

These findings demonstrate that M-HB-self-applied-tDCS is a suitable approach for reducing uncontrolled and emotional eating, with greater efficacy in L-DLPFC. Furthermore, these results revealed the influence of fibromyalgia symptoms on M-HB-self-applied-tDCS's, with M1 being particularly effective in mitigating food cravings and reducing fibromyalgia symptoms.

Efficacy and safety of n-3 fatty acids supplementation on depression: a systematic review and dose-response meta-analysis of randomised controlled trials

We aimed to investigate the effectiveness of n-3 fatty acids supplementation on the risk of developing depression, depressive symptoms and remission of depression. We searched PubMed, Scopus and Web of Science from inception to December 2022 to find randomised trials of n-3 fatty acids supplementation in adults. We conducted random-effects meta-analyses to estimate standardised mean differences (SMD) and 95 % CI for continuous outcomes and risk difference and 95 % CI for binary outcomes. A total of sixty-seven trials were included. Each 1 g/d n-3 fatty acids supplementation significantly improved depressive symptoms in adults with and without depression (moderate-certainty evidence), with a larger improvement in patients with existing depression. Dose-response analyses indicated a U-shaped effect in patients with existing depression, with the greatest improvement at 1·5 g/d. The analysis showed that n-3 fatty acid supplementation significantly increased depression remission by 19 more per 100 in patients with depression (low-certainty evidence). Supplementation with n-3 fatty acids did not reduce the risk of developing depression among the general population, but it did improve the severity of depression among patients with existing depression.

Connectivity-guided intermittent theta burst versus repetitive transcranial magnetic stimulation for treatment-resistant depression: a randomized controlled trial

Disruption in reciprocal connectivity between the right anterior insula and the left dorsolateral prefrontal cortex is associated with depression and may be a target for neuromodulation. In a five-center, parallel, double-blind, randomized controlled trial we personalized resting-state functional magnetic resonance imaging neuronavigated connectivity-guided intermittent theta burst stimulation (cgiTBS) at a site based on effective connectivity from the right anterior insula to the left dorsolateral prefrontal cortex. We tested its efficacy in reducing the primary outcome depression symptoms measured by the GRID Hamilton Depression Rating Scale 17-item over 8, 16 and 26 weeks, compared with structural magnetic resonance imaging (MRI) neuronavigated repetitive transcranial magnetic stimulation (rTMS) delivered at the standard stimulation site (F3) in patients with 'treatment-resistant depression'. Participants were randomly assigned to 20 sessions over 4-6 weeks of either cgiTBS (n = 128) or rTMS (n = 127) with resting-state functional MRI at baseline and 16 weeks. Persistent decreases in depressive symptoms were seen over 26 weeks, with no differences between arms on the primary outcome GRID Hamilton Depression Rating Scale 17-item score (intention-to-treat adjusted mean, -0.31, 95% confidence interval (CI) -1.87, 1.24, P = 0.689). Two serious adverse events were possibly related to TMS (mania and psychosis). MRI-neuronavigated cgiTBS and rTMS were equally effective in patients with treatment-resistant depression over 26 weeks (trial registration no. ISRCTN19674644).

Psychopharmacology in children and adolescents: unmet needs and opportunities

Psychopharmacological treatment is an important component of the multimodal intervention approach to treating mental health conditions in children and adolescents. Currently, there are many unmet needs but also opportunities, alongside possible risks to consider, regarding the pharmacological treatment of mental health conditions in children and adolescents. In this Position Paper, we highlight and address these unmet needs and opportunities, including the perspectives of clinicians and researchers from the European College of Neuropsychopharmacology-Child and Adolescent Network, alongside those of experts by lived experience from national and international associations, via a survey involving 644 participants from 13 countries, and of regulators, through representation from the European Medicines Agency. We present and discuss the evidence base for medications currently used for mental disorders in children and adolescents, medications in the pipeline, opportunities in the development of novel medications, crucial priorities for the conduct of future clinical studies, challenges and opportunities in terms of the regulatory and legislative framework, and innovations in the way research is conducted, reported, and promoted.

Digitally managing depression: A fully remote randomised attention-placebo controlled trial

Background

Depression is a common and disabling condition. Digital apps may augment or facilitate care, particularly in under-served populations. We tested the efficacy of juli, a digital self-management app for depression in a fully remote randomised controlled trial.

Methods

A pragmatic randomised controlled trial that included participants aged > 18 who self-identified as having depression and scored > 5 on the Patient Health Questionnaire-8. Participants were randomly assigned (1:1) to receive juli for 8 weeks or a limited attention-placebo control app. Our primary outcome was the difference in Patient Health Questionnaire-8 scores at 8 weeks. Secondary outcomes were remission, minimal clinically important difference, worsening of depression, and health-related quality of life. Analyses were per-protocol (primary), and modified and full intention-to-treat (secondary). The trial was registered at ISRCTN (ISRCTN12329547).

Results

Between May 2021 and January 2023, we randomised 908 participants. 662 completed the week 2 outcome assessment and were included in the modified intention-to-treat analysis, and 456 completed the week 8 outcome assessments (per-protocol). In the per-protocol analysis, the juli group had a greater reduction in Patient Health Questionnaire-8 score (10.78, standard deviation 6.26) than the control group (11.88, standard deviation 5.73) by week 8 (baseline adjusted β-coefficient -0.94, 95% CI: -1.87 to -0.22, p = 0.045). Achieving remission and a minimal clinically important difference was more likely in the juli group at 8 weeks (adjusted odds ratios 2.22, 95% CI: 1.45-3.39, p < 0.001 and 1.56, 95% CI: 1.08-2.27, p = 0.018, respectively). There were no between-group differences in health-related quality of life or worsening of depression. Modified and full intention-to-treat analyses found similar results, but the primary outcome was non-significant.

Conclusion

The use of juli for 8 weeks resulted in a small reduction in symptoms of depression compared with an attention-placebo control. The juli app is a digital self-management tool that could increase the accessibility of evidence-based depression treatments.

Deep Brain Stimulation (DBS) in Treatment-Resistant Depression (TRD): Hope and Concern

In this chapter, we explore the historical evolution, current applications, and future directions of Deep Brain Stimulation (DBS) for Treatment-Resistant Depression (TRD). We begin by highlighting the early efforts of neurologists and neurosurgeons who laid the foundations for today's DBS techniques, moving from controversial lobotomies to the precision of stereotactic surgery. We focus on the advent of DBS, emphasizing its emergence as a significant breakthrough for movement disorders and its extension to psychiatric conditions, including TRD. We provide an overview of the neural networks implicated in depression, detailing the rationale for the choice of common DBS targets. We also cover the technical aspects of DBS, from electrode placement to programming and parameter selection. We then critically review the evidence from clinical trials and open-label studies, acknowledging the mixed outcomes and the challenges posed by placebo effects and trial design. Safety and ethical considerations are also discussed. Finally, we explore innovative directions for DBS research, including the potential of closed-loop systems, dual stimulation strategies, and noninvasive alternatives like ultrasound neuromodulation. In the last section, we outline recommendations for future DBS studies, including the use of alternative designs for placebo control, the collection of neural and behavioral recordings, and the application of machine-learning approaches.

Placebo effects in mental health disorders: protocol for an umbrella review

INTRODUCTION

Given the high prevalence of mental health disorders and their significant socioeconomic burden, there is a need to develop improved treatments, and to evaluate them through placebo-controlled trials. However, the magnitude of the placebo response in randomised controlled trials to test medications may be substantial, affecting their interpretation. Therefore, improved understanding of the patient, trial and mental disorder factors that influence placebo responses would inform clinical trial design to better detect active treatment effects. There is a growing literature exploring the placebo response within specific mental health disorders, but no overarching synthesis of this research has been produced to date. We present a protocol for an umbrella review of systematic reviews and/or meta-analyses in which we aim to understand the effect size and potential predictors of placebo response within, and across, mental health disorders.

METHODS AND ANALYSIS

We will systematically search databases (Medline, PsycINFO, EMBASE+EMBASE Classic, Web of Knowledge) for systematic reviews and/or meta-analyses that report placebo effect size in clinical trials in patients with mental health disorders (initial search date 23 October 2022). Screening of abstracts and full texts will be done in pairs. We will extract data to qualitatively examine how placebo effect size varies across mental health disorders. We also plan to qualitatively summarise predictors of increased placebo response identified either quantitatively (eg, through meta-regression) or qualitatively. Risk of bias will be assessed using the AMSTAR-2 tool. We aim to not only summarise the current literature but also to identify gaps in knowledge and generate further hypotheses.

ETHICS AND DISSEMINATION

We do not believe there are any specific ethical considerations relevant to this study. We will publish the results in a peer-reviewed journal.

Placebo response in sham-acupuncture-controlled trials for migraine: A systematic review and meta-analysis

AIM

To understand the placebo response of acupuncture and its effect on migraine and optimize the design of future acupuncture clinical trials on migraine treatment.

METHODS

Randomized controlled trials with sham acupuncture as a control in migraine treatment were searched in four English databases from inception to September 1, 2022. The primary outcome was placebo response rate. Secondary outcomes were migraine symptoms, emotional condition, and quality of life. Factors associated with placebo response were also explored. Results were combined using risk difference (RD) or standardized mean difference (SMD) and 95% confidence interval (CI) with a random effects model.

RESULTS

The final analysis included 21 studies involving 1177 patients. The pooled response rate of sham acupuncture was 0.34 (RD, 95% CI 0.23-0.45, I2 89.8%). The results (SMD [95% CI]) showed significant improvements in migraine symptoms (pain intensity -0.56 [-0.73 to -0.38], and episode conditions -0.55 [-0.75 to -0.35]); emotional condition (anxiety scale -0.49 [-0.90 to -0.08] and depression scale -0.21 [-0.40 to -0.03]); and quality of life on the Migraine-Specific Quality-of-Life Questionnaire (restrictive 0.78 [0.61-0.95]; preventive 0.52 [0.35-0.68]; and emotional 0.45 [0.28-0.62]) and on the Medical Outcomes Study Short-Form (physical 0.48 [0.34-0.62] and mental 0.21 [0.02-0.41]). Only acupuncture treatment frequency had a significant impact on the placebo response rate (RD 0.49 vs. 0.14; p = 0.00).

CONCLUSIONS

The effect sizes for placebo response of sham acupuncture varied across migraine treatment trials. Further studies should routinely consider adjusting for a more complete set of treatment factors.

Placebo Response among Different Types of Sham Acupuncture for Low Back Pain: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Low back pain (LBP) is a prevalent and debilitating condition that poses a significant burden on healthcare systems. Acupuncture has been proposed as a promising intervention for LBP, but the evidence supporting its specific effect is insufficient, and the use of sham acupuncture as a control in clinical trials presents challenges due to variations in sham acupuncture techniques and the magnitude of the placebo effect.

OBJECTIVE

To investigate the magnitude of the placebo response of sham acupuncture in trials of acupuncture for nonspecific LBP, and to assess whether different types of sham acupuncture are associated with different responses.

METHODS

Four databases including PubMed, EMBASE, MEDLINE, and the Cochrane Library were searched through April 15, 2023, and randomized controlled trials (RCTs) were included if they randomized patients with LBP to receive acupuncture or sham acupuncture intervention. The main outcomes included the placebo response in pain intensity, back-specific function and quality of life. Placebo response was defined as the change in these outcome measures from baseline to the end of treatment. Random-effects models were used to synthesize the results, standardized mean differences (SMDs, Hedges'g) were applied to estimate the effect size.

RESULTS

A total of 18 RCTs with 3,321 patients were included. Sham acupuncture showed a noteworthy pooled placebo response in pain intensity in patients with LBP [SMD -1.43, 95% confidence interval (CI) -1.95 to -0.91, I2=89%]. A significant placebo response was also shown in back-specific functional status (SMD -0.49, 95% CI -0.70 to -0.29, I2=73%), but not in quality of life (SMD 0.34, 95% CI -0.20 to 0.88, I2=84%). Trials in which the sham acupuncture penetrated the skin or performed with regular needles had a significantly higher placebo response in pain intensity reduction, but other factors such as the location of sham acupuncture did not have a significant impact on the placebo response.

CONCLUSIONS

Sham acupuncture is associated with a large placebo response in pain intensity among patients with LBP. Researchers should also be aware that the types of sham acupuncture applied may potentially impact the evaluation of the efficacy of acupuncture. Nonetheless, considering the nature of placebo response, the effect of other contextual factors cannot be ruled out in this study. (PROSPERO registration No. CRD42022304416).

Plasma Brain-Derived Neurotrophic Factor Levels in First-Episode and Recurrent Major Depression and before and after Bright Light Therapy in Treatment-Resistant Depression

Brain-derived neurotrophic factor (BDNF) is implicated in the etiology and treatment response in major depressive disorder (MDD). However, peripheral BDNF concentrations have not been compared across different MDD stages. Bright light therapy (BLT) offers some potential in treatment-resistant depression (TRD), but its effects on BDNF levels are unknown. This study included a cross-sectional analysis of plasma BDNF concentration in females with TRD, unmedicated MDD patients, and healthy controls (HC), and measurements of longitudinal BLT effects on plasma BDNF levels in TRD patients. The present study included 55 drug-naïve, first-episode patients, 25 drug-free recurrent-episode MDD patients, 71 HC participants, and 54 TRD patients. Patients were rated by Hamilton Depression Rating Scale (HAMD)-17 and the Montgomery-Åsberg Depression Rating Scale (MADRS). Patients with TRD received BLT during 4 weeks. The total HAMD-17 and MADRS scores decreased following BLT. All patient groups had lower plasma BDNF than HC, but BDNF levels did not differ between first- and recurrent-episode BDNF patients and TRD patients before or after BLT. However, responders and remitters to BLT had higher post-treatment plasma BDNF concentrations than patients who did not achieve response or remission. The changes in plasma BDNF levels may be candidates for biomarkers of treatment response to BLT in TRD patients.

Single-Dose Psilocybin Treatment for Major Depressive Disorder: A Randomized Clinical Trial

Importance

Psilocybin shows promise as a treatment for major depressive disorder (MDD).

Objective

To evaluate the magnitude, timing, and durability of antidepressant effects and safety of a single dose of psilocybin in patients with MDD.

Design, Setting, and Participants

In this phase 2 trial conducted between December 2019 and June 2022 at 11 research sites in the US, participants were randomized in a 1:1 ratio to receive a single dose of psilocybin vs niacin placebo administered with psychological support. Participants were adults aged 21 to 65 years with a Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition diagnosis of MDD of at least 60 days' duration and moderate or greater symptom severity. Exclusion criteria included history of psychosis or mania, active substance use disorder, and active suicidal ideation with intent. Participants taking psychotropic agents who otherwise met inclusion/exclusion criteria were eligible following medication taper. Primary and secondary outcomes and adverse events (AEs) were assessed at baseline (conducted within 7 days before dosing) and at 2, 8, 15, 29, and 43 days after dosing.

Interventions

Interventions were a 25-mg dose of synthetic psilocybin or a 100-mg dose of niacin in identical-appearing capsules, each administered with psychological support.

Main Outcomes and Measures

The primary outcome was change in central rater-assessed Montgomery-Asberg Depression Rating Scale (MADRS) score (range, 0-60; higher scores indicate more severe depression) from baseline to day 43. The key secondary outcome measure was change in MADRS score from baseline to day 8. Other secondary outcomes were change in Sheehan Disability Scale score from baseline to day 43 and MADRS-defined sustained response and remission. Participants, study site personnel, study sponsor, outcome assessors (raters), and statisticians were blinded to treatment assignment.

Results

A total of 104 participants (mean [SD] age, 41.1 [11.3] years; 52 [50%] women) were randomized (51 to the psilocybin group and 53 to the niacin group). Psilocybin treatment was associated with significantly reduced MADRS scores compared with niacin from baseline to day 43 (mean difference,-12.3 [95% CI, -17.5 to -7.2]; P <.001) and from baseline to day 8 (mean difference, -12.0 [95% CI, -16.6 to -7.4]; P < .001). Psilocybin treatment was also associated with significantly reduced Sheehan Disability Scale scores compared with niacin (mean difference, -2.31 [95% CI, 3.50-1.11]; P < .001) from baseline to day 43. More participants receiving psilocybin had sustained response (but not remission) than those receiving niacin. There were no serious treatment-emergent AEs; however, psilocybin treatment was associated with a higher rate of overall AEs and a higher rate of severe AEs.

Conclusions and Relevance

Psilocybin treatment was associated with a clinically significant sustained reduction in depressive symptoms and functional disability, without serious adverse events. These findings add to increasing evidence that psilocybin-when administered with psychological support-may hold promise as a novel intervention for MDD.

Trial Registration

ClinicalTrials.gov Identifier: NCT03866174.

The longer, the better ? Longer left-sided prolonged intermittent theta burst stimulation in patients with major depressive disorder: A randomized sham-controlled study

BACKGROUND

Prolonged intermittent theta-burst stimulation (iTBS) is effective for major depressive disorder (MDD). However, whether longer piTBS treatment in a single session could have antidepressant efficacy remains elusive. Therefore, this double-blind, randomized, sham-controlled study aimed to investigate the antidepressant efficacy of 2 daily piTBS sessions for treating MDD patients with a history of poor responses to at least 1 adequate antidepressant trial in the current episode.

METHODS

All patients received 2 uninterrupted sessions per day for 10 weekdays (i.e., 2 weeks; a total of 20 sessions). Seventy-two patients were recruited and 1:1:1 randomly assigned to one of three groups: piTBS (piTBSx2), 10-Hz rTMS (rTMSx2), or sham treatment (shamx2, randomly assigned to piTBS or rTMS). 10-Hz rTMS group was included as an active comparison group to enhance assay sensitivity.

RESULTS

piTBSx2 group had significantly more responders at week 2 than shamx2 group, but it did not yield better antidepressant effects regarding the %depression changes. The changes of antidepressant scores were not different among the three groups at week 1 (-26.2% vs. -23.3% vs. -22.%) or at week 2 (-34.1% vs. -37.1% vs. -30.1%). Longer treatment duration did not result in stronger placebo effects [sham(piTBS)x2: - 31.7% vs. sham(rTMS)x2: - 26.7%].

CONCLUSION

The present sham-controlled study confirmed that piTBS is an effective antidepressant option, but found no evidence to support that longer piTBS treatment duration resulted in more rapid or better antidepressant effects. A high placebo effect was observed, but longer treatment duration of brain stimulation was not linearly associated with stronger placebo effects.

Placebo response of sham acupuncture in patients with primary dysmenorrhea: A meta-analysis

BACKGROUND

The placebo response of sham acupuncture in patients with primary dysmenorrhea is a substantial factor associated with analgesia. However, the magnitude of the placebo response is unclear.

OBJECTIVE

This meta-analysis assessed the effects of sham acupuncture in patients with primary dysmenorrhea and the factors contributing to these effects.

SEARCH STRATEGY

PubMed, Embase, Web of Science, and Cochrane CENTRAL databases were searched from inception up to August 20, 2022.

INCLUSION CRITERIA

Randomized controlled trials (RCTs) using sham acupuncture as a control for female patients of reproductive age with primary dysmenorrhea were included.

DATA EXTRACTION AND ANALYSIS

Pain intensity, retrospective symptom scale, and health-related quality of life were outcome measures used in these trials. Placebo response was defined as the change in the outcome of interest from baseline to endpoint. We used standardized mean difference (SMD) to estimate the effect size of the placebo response.

RESULTS

Thirteen RCTs were included. The pooled placebo response size for pain intensity was the largest (SMD = -0.99; 95% confidence interval [CI], -1.31 to -0.68), followed by the retrospective symptom scale (Total frequency rating score: SMD = -0.20; 95% CI, -0.80 to -0.39. Average severity score: SMD = -0.35; 95% CI, -0.90 to -0.20) and physical component of SF-36 (SMD = 0.27; 95% CI, -0.17 to 0.72). Studies using blunt-tip needles, single-center trials, studies with a low risk of bias, studies in which patients had a longer disease course, studies in which clinicians had < 5 years of experience, and trials conducted outside Asia were more likely to have a lower placebo response.

CONCLUSION

Strong placebo response and some relative factors were found in patients with primary dysmenorrhea. PROSPERO registration number: CRD42022304215. Please cite this article as: Sun CY, Xiong ZY, Sun CY, Ma PH, Liu XY, Sun CY, Xin ZY, Liu BY, Liu CZ, Yan SY. Placebo response of sham acupuncture in patients with primary dysmenorrhea: A meta-analysis. J Integr Med. 2023; 21(5): 455-463.

Study protocol: effects of treatment expectation toward repetitive transcranial magnetic stimulation (rTMS) in major depressive disorder-a randomized controlled clinical trial

BACKGROUND

Patients' expectations toward any given treatment are highly important for the effectiveness of such treatment, as has been demonstrated for several disorders. In particular, in major depressive disorder (MDD), one of the most frequent and most serious mental disorders with severe consequences for the affected, the augmentation of available treatment options could mean a ground-breaking success. Repetitive transcranial magnetic stimulation (rTMS), a new, non-invasive, and well-tolerated intervention with proven effects in the treatment of MDD, appears particularly suitable in this context as it is assumed to exert its effect via structures implicated in networks relevant for both expectation and depression.

METHODS

All patients will receive rTMS according to its approval. Half of the patients will be randomized to a psychological intervention, which is a comprehensive medical consultation aiming to improve positive treatment expectations; the control group will receive a conventional informed consent discussion (in the sense of a treatment-as-usual condition). As outcome parameters, instruments for both self-assessment and external assessment of depression symptoms will be applied. Furthermore, psycho-immunological parameters such as inflammation markers and the cortisol awakening response in saliva will be investigated. Resting-state functional magnetic resonance imaging (rs fMRI) will be performed to analyze functional connectivity, including the cerebellum, and to identify neuronal predictors of expectation effects. In addition, possible cerebellar involvement will be assessed based on a cerebellar-dependent motor learning paradigm (i.e., eyeblink conditioning).

DISCUSSION

In this study, the effects of treatment expectations towards rTMS are investigated in patients with MDD. The aim of this study is to identify the mechanisms underlying the expectation effects and, beyond that, to expand the potential of non-invasive and well-tolerated treatments of MDD.

TRIAL REGISTRATION

German Registry of Clinical Studies (DRKS DRKS00028017. Registered on 2022/03/07. URL: https://www.drks.de/drks_web/ .

Adjunctive neuronavigated accelerated continuous theta-burst stimulation in obsessive-compulsive disorder: a randomized sham-controlled study

BACKGROUND

Approximately 40% of patients treated for obsessive-compulsive disorder (OCD) do not respond to standard and second-line augmentation treatments leading to the exploration of alternate biological treatments. Continuous theta burst stimulation (cTBS) is a form of repetitive transcranial magnetic stimulation inducing more rapid and longer-lasting effects on synaptic plasticity than the latter. To the best of our knowledge, only one recent study and a case report investigated the effect of cTBS at the supplementary motor area (SMA) in OCD.

OBJECTIVE

This study aimed to examine the effect of accelerated robotized neuronavigated cTBS over SMA in patients with OCD.

METHODS

A total of 32 patients with OCD were enrolled and randomized into active and sham cTBS groups. For active cTBS stimulation, an accelerated protocol was used. Bursts of three stimuli at 50 Hz, at 80% of MT, repeated at 5 Hz were used. Daily 2 sessions of 900 pulses each, for a total of 30 sessions over 3 wk (weekly 10 sessions), were given. Yale-Brown Obsessive-Compulsive Rating Scale (YBOCS), Clinical Global Impressions scale (CGI), Hamilton Depression Rating Scale (HAM-D), and Hamilton Anxiety Rating Scale (HAM-A) were administered at baseline and at end of weeks 3 and 8.

RESULTS

A total of 26 patients completed the study. Active cTBS group showed significant group × time effect in YBOCS obsession (P < .001, η2 = 0.288), compulsion (P = .004, η2 = 0.207), YBOCS total (P < .001, η2 = 0.288), CGI-S (P = .010, η2 = 0.248), CGI-C (P = .010, η2 = 0.248), HAM-D (P = .014, η2 = 0.224) than sham cTBS group.

CONCLUSIONS

Findings from our study suggest that adjunctive accelerated cTBS significantly improves psychopathology, severity of illness, and depression among patients with OCD. Future studies with larger sample sizes will add to our knowledge.

Possible Strategies to Mitigate Placebo or Vehicle Response in Dry Eye Disease Trials: A Narrative Review

Many candidate drugs for dry eye disease (DED) have been assessed over the years in pursuit of demonstrating efficacy in both signs and symptoms. However, patients with DED have very limited treatment options for management of both signs and symptoms of DED. There are several potential reasons behind this including the placebo or vehicle response, which is a frequent issue observed in DED trials. A high magnitude of vehicle response interferes with the estimation of a drug's treatment effect and may lead to failure of a clinical trial. To address these concerns, Tear Film and Ocular Surface Society International Dry Eye Workshop II taskforce has recommended a few study design strategies to minimize vehicle response observed in DED trials. This review briefly describes the factors that lead to placebo/vehicle response in DED trials and focuses on the aspects of clinical trial design that can be improved to mitigate vehicle response. In addition, it presents the observations from a recent ECF843 phase 2b study, wherein the study design approach consisted of a vehicle run-in phase, withdrawal phase, and masked treatment transition, and led to consistent data for DED signs and symptoms and reduced vehicle response post randomization.

Illuminating the way: the role of bright light therapy in the treatment of depression

INTRODUCTION

Despite the growing number of different therapeutic options, treatment of depression is still a challenge. A broader perspective reveals the benefits of bright light therapy (BLT). It stimulates intrinsically photosensitive retinal ganglion cells, which induces a complex cascade of events, including alterations in melatonergic, neurotrophic, GABAergic, glutamatergic, noradrenergic, serotonergic systems, and HPA axis, suggesting that BLT effects expand beyond the circadian pacemaker.

AREAS COVERED

In this review, the authors present and discuss recent data of BLT in major depressive disorder, non-seasonal depression, bipolar depression or depressive phase of bipolar disorder, and seasonal affective disorder, as well as in treatment-resistant depression (TRD). The authors further highlight BLT effects in various depressive disorders compared to placebo and report data from several studies suggesting a response to BLT in TRD. Also, the authors report data showing that BLT can be used both as a monotherapy or in combination with other pharmacological treatments.

EXPERT OPINION

BLT is an easy-to-use and low-budget therapy with good tolerability. Future studies should focus on clinical and biological predictors of response to BLT, on defining specific populations which may benefit from BLT and establishing treatment protocols regarding timing, frequency, and duration of BLT.