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Hird EJ, Diederen K, Leucht S, Jensen KB, McGuire P. The Placebo Effect in Psychosis: Why It Matters and How to Measure It. BIOLOGICAL PSYCHIATRY GLOBAL OPEN SCIENCE 2023; 3:605-613. [PMID: 37881581 PMCID: PMC10593894 DOI: 10.1016/j.bpsgos.2023.02.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 12/04/2022] [Accepted: 02/20/2023] [Indexed: 03/07/2023] Open
Abstract
Psychosis is characterized by unusual percepts and beliefs in the form of hallucinations and delusions. Antipsychotic medication, the primary treatment for psychosis, is often ineffective and accompanied by severe side effects, but research has not identified an effective alternative in several decades. One reason that clinical trials fail is that patients with psychosis tend to show a significant therapeutic response to inert control treatments, known as the placebo effect, which makes it difficult to distinguish drug effects from placebo effects. Conversely, in clinical practice, a strong placebo effect may be useful because it could enhance the overall treatment response. Identifying factors that predict large placebo effects could improve the future outlook of psychosis treatment. Biomarkers of the placebo effect have already been suggested in pain and depression, but not in psychosis. Quantifying markers of the placebo effect would have the potential to predict placebo effects in psychosis clinical trials. Furthermore, the placebo effect and psychosis may represent a shared neurocognitive mechanism in which prior beliefs are weighted against new sensory information to make inferences about reality. Examining this overlap could reveal new insights into the mechanisms underlying psychosis and indicate novel treatment targets. We provide a narrative review of the importance of the placebo effect in psychosis and propose a novel method to assess it.
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Affiliation(s)
- Emily J. Hird
- Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, England
| | - Kelly Diederen
- Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, England
| | - Stefan Leucht
- Department of Psychiatry and Psychotherapy, Technical University of Munich, Munich, Germany
| | - Karin B. Jensen
- Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden
| | - Philip McGuire
- Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, England
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Tchouankam T, Estabrooks P, Cloyd A, Notice M, Teel-Williams M, Smolsky A, Burnett P, Alexis G, Conley T, Partridge EJ, Hogan P, Thorpe R, King KM. Recruiting Low-Income African American Men in Mental Health Research: A Community-Based Participatory Research Feasibility Study. Am J Mens Health 2021; 15:15579883211018418. [PMID: 34027740 PMCID: PMC8142009 DOI: 10.1177/15579883211018418] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
African Americans (AAs) are 20% more likely to develop serious psychological distress compared to Whites but are less likely to use mental health services. The study objective was to evaluate the effectiveness of recruitment strategies to engage AA fathers in a mental health intervention. Using the community-based participatory research (CBPR) approach, a community-academic partnership (CAP) developed and implemented direct and indirect referral strategies to engage AA fathers in a mental health intervention. Direct referral strategies focused on community partner identification of potentially eligible participants, providing information about the study (i.e., study flyer), and referring potential participants to the study. Indirect referrals included posting flyers in local businesses frequented by AA men, radio advertisements, and social media posts from community organizations. From January to October 2019, 50 direct and 1388 indirect referrals were documented, yielding 24 participants screened and 15 enrolled. Of all participants screened, 58% were referred through indirect referral, 38% were referred directly by community partners, and 4% of the participants were referred through both direct and indirect referrals. Twenty percent of those exposed to the direct referral methods and 1% of those exposed to the indirect referral methods were enrolled. The indirect referrals accounted for 60% of enrollment, whereas the direct referrals accounted for 33.3% of enrollment. Collaborating with the community partners to engage hard-to-reach populations in mental health studies allowed for broad dissemination of recruitment methods, but still resulted in low participant accrual. Additional focus on increasing direct referral methods appears to be a fruitful area of CBPR.
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Affiliation(s)
| | | | | | - Maxine Notice
- University of Nebraska Medical Center, Omaha, Nebraska, USA
| | | | - Ann Smolsky
- Charles Drew Health Center, Inc., Omaha, Nebraska, USA
| | - Paul Burnett
- Charles Drew Health Center, Inc., Omaha, Nebraska, USA
| | | | - Tori Conley
- Charles Drew Health Center, Inc., Omaha, Nebraska, USA
| | | | - Payton Hogan
- Charles Drew Health Center, Inc., Omaha, Nebraska, USA
| | | | - Keyonna M King
- University of Nebraska Medical Center, Omaha, Nebraska, USA
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3
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Placebo response mitigation with a participant-focused psychoeducational procedure: a randomized, single-blind, all placebo study in major depressive and psychotic disorders. Neuropsychopharmacology 2021; 46:844-850. [PMID: 33244149 PMCID: PMC8026614 DOI: 10.1038/s41386-020-00911-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 10/06/2020] [Accepted: 11/02/2020] [Indexed: 11/30/2022]
Abstract
The remarkably high and growing placebo response rates in clinical trials for CNS indications, such as depression and schizophrenia, constitute a major challenge for the drug development enterprise. Despite extensive literature on participant expectancies and other potent psychosocial factors that perpetuate placebo response, no empirically validated participant-focused strategies to mitigate this phenomenon have been available. This study evaluated the efficacy of the Placebo-Control Reminder Script (PCRS), a brief interactive procedure that educates participants about factors known to cause placebo response, which was administered prior to the primary outcome assessments to subjects with major depressive or psychotic disorders who had at least moderate depression. Participants were informed they would participate in a 2-week randomized clinical trial with a 50% chance of receiving either an experimental antidepressant medication or placebo. In actuality, all participants received placebo. Participants randomly assigned to receive the PCRS (n = 70) reported significantly smaller reductions (i.e., less placebo response) in depression than those who did not receive the PCRS (n = 67). The magnitude of this effect was medium (Cohen's d = 0.40) and was not significantly impacted by diagnostic status. The number of adverse events (i.e., nocebo effect) was also lower in the PCRS group, particularly in the first week of the study. These findings suggest that briefly educating participants about placebo response factors can help mitigate the large placebo response rates that are increasingly seen in failed CNS drug development programs.
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Nicoletti F, Orlando R, Di Menna L, Cannella M, Notartomaso S, Mascio G, Iacovelli L, Matrisciano F, Fazio F, Caraci F, Copani A, Battaglia G, Bruno V. Targeting mGlu Receptors for Optimization of Antipsychotic Activity and Disease-Modifying Effect in Schizophrenia. Front Psychiatry 2019; 10:49. [PMID: 30890967 PMCID: PMC6413697 DOI: 10.3389/fpsyt.2019.00049] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 01/23/2019] [Indexed: 01/03/2023] Open
Abstract
Metabotropic glutamate (mGlu) receptors are considered as candidate drug targets for the treatment of schizophrenia. These receptors form a family of eight subtypes (mGlu1 to -8), of which mGlu1 and -5 are coupled to Gq/11, and all other subtypes are coupled to Gi/o. Here, we discuss the possibility that selective ligands of individual mGlu receptor subtypes may be effective in controlling the core symptoms of schizophrenia, and, in some cases, may impact mechanisms underlying the progression of the disorder. Recent evidence indicates that activation of mGlu1 receptors inhibits dopamine release in the meso-striatal system. Hence, selective positive allosteric modulators (PAMs) of mGlu1 receptors hold promise for the treatment of positive symptoms of schizophrenia. mGlu5 receptors are widely expressed in the CNS and regulate the activity of cells that are involved in the pathophysiology of schizophrenia, such as cortical GABAergic interneurons and microglial cells. mGlu5 receptor PAMs are under development for the treatment of schizophrenia and cater the potential to act as disease modifiers by restraining neuroinflammation. mGlu2 receptors have attracted considerable interest because they negatively modulate 5-HT2A serotonin receptor signaling in the cerebral cortex. Both mGlu2 receptor PAMs and orthosteric mGlu2/3 receptor agonists display antipsychotic-like activity in animal models, and the latter drugs are inactive in mice lacking mGlu2 receptors. So far, mGlu3 receptors have been left apart as drug targets for schizophrenia. However, activation of mGlu3 receptors boosts mGlu5 receptor signaling, supports neuronal survival, and drives microglial cells toward an antiinflammatory phenotype. This strongly encourages research of mGlu3 receptors in schizophrenia. Finally, preclical studies suggest that mGlu4 receptors might be targeted by novel antipsychotic drugs, whereas studies of mGlu7 and mGlu8 receptors in animal models of psychosis are still at their infancy.
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Affiliation(s)
- Ferdinando Nicoletti
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy.,IRCCS Neuromed, Pozzilli, Italy
| | - Rosamaria Orlando
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | | | | | | | | | - Luisa Iacovelli
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Francesco Matrisciano
- Department of Psychiatry, The Psychiatric Institute, College of Medicine, University of Illinois, Chicago, IL, United States
| | | | - Filippo Caraci
- Department of Drug Sciences, University of Catania, Catania, Italy.,Oasi Research Institute (IRCCS), Troina, Italy
| | - Agata Copani
- Department of Drug Sciences, University of Catania, Catania, Italy.,Institute of Biostructure and Bioimaging, National Research Council, Catania, Italy
| | | | - Valeria Bruno
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy.,IRCCS Neuromed, Pozzilli, Italy
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Fraguas D, Díaz-Caneja CM, Pina-Camacho L, Umbricht D, Arango C. Predictors of Placebo Response in Pharmacological Clinical Trials of Negative Symptoms in Schizophrenia: A Meta-regression Analysis. Schizophr Bull 2019; 45:57-68. [PMID: 29370436 PMCID: PMC6293224 DOI: 10.1093/schbul/sbx192] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We conducted a meta-regression analysis of all double-blind, randomized, placebo-controlled clinical trials (DBRCTs) reporting effects of drug and placebo on negative symptoms in people with stable schizophrenia and predominant or prominent negative symptoms to assess predictors of placebo response in these individuals. We used Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines for systematic reviews and meta-analyses to conduct a systematic literature search to identify DBRCTs assessing treatment efficacy on negative symptoms, as primary outcome, in patients with stable schizophrenia and predominant or prominent negative symptoms. We used Cohen's d, with 95% CIs, as the effect size measure for placebo response, based on negative symptom change scores from baseline to endpoint (range 4 to 24 wk) in the placebo-treated group. We included 18 DBRCTs from 17 publications, assessing the effect of 13 drugs vs placebo on negative symptoms and comprising 998 patients, in the meta-regression analyses. Overall, drugs showed greater efficacy than placebo in reducing negative symptoms, with small effect size (Cohen's d: 0.208, P = .020). Placebo response was significant (P < .001) and clinically relevant (Cohen's d: 2.909), but there was significant heterogeneity and high risk of publication bias. Multivariable meta-regression analyses showed that larger numbers of arms in the trial, larger numbers of study sites and industry sponsorship were significant moderators of placebo response in this population. Our results suggest that some clinical trial design and operational factors affect the level of placebo response in such studies, thus highlighting the need for designs better suited to assess these outcomes.
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Affiliation(s)
- David Fraguas
- Department of Child and Adolescent Psychiatry, Hospital General Universitario Gregorio Marañón, IiSGM, School of Medicine, Universidad Complutense, CIBERSAM. Madrid, Spain,To whom correspondence should be addressed; Department of Child and Adolescent Psychiatry, Hospital General Universitario Gregorio Marañón, Calle Ibiza 43, Madrid 28009, Spain; tel: +34-914265005, fax: +34-914265004, e-mail:
| | - Covadonga M Díaz-Caneja
- Department of Child and Adolescent Psychiatry, Hospital General Universitario Gregorio Marañón, IiSGM, School of Medicine, Universidad Complutense, CIBERSAM. Madrid, Spain
| | - Laura Pina-Camacho
- Department of Child and Adolescent Psychiatry, Hospital General Universitario Gregorio Marañón, IiSGM, School of Medicine, Universidad Complutense, CIBERSAM. Madrid, Spain,Department of Child and Adolescent Psychiatry, Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, UK
| | - Daniel Umbricht
- Neuroscience, Ophthalmology, Rare Diseases, Roche Pharma Research & Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Basel, Switzerland
| | - Celso Arango
- Department of Child and Adolescent Psychiatry, Hospital General Universitario Gregorio Marañón, IiSGM, School of Medicine, Universidad Complutense, CIBERSAM. Madrid, Spain
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Liu Y, Pencheon E, Hunter RM, Moncrieff J, Freemantle N. Recruitment and retention strategies in mental health trials - A systematic review. PLoS One 2018; 13:e0203127. [PMID: 30157250 PMCID: PMC6114918 DOI: 10.1371/journal.pone.0203127] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 08/15/2018] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Recruitment and retention challenges are very common in mental health randomised trials. Investigators utilise different methods to improve recruitment or retention. However, evidence of the effectiveness and efficiency of these strategies in mental health has not been synthesised. This systematic review is to investigate and assess the effectiveness and cost-effectiveness of different strategies to improve recruitment and retention in mental health randomised trials. METHODS AND MATERIALS MEDLINE, EMBASE, the Cochrane Methodology Register and PsycINFO were searched from beginning of record up to July 2016. Randomised trials involving participants with mental health problems which compared different strategies for recruitment or retention were selected. Two authors independently screened identified studies for eligibility. RESULTS A total of 5,157 citations were identified. Thirteen articles were included, 11 on recruitment and 2 on retention. Three randomised controlled trials compared different recruitment strategies, none of which found statistically significant differences between the interventional recruitment strategies and the routine recruitment methods. Retrospective comparisons of recruitment methods showed that non-web-based advertisement and recruitment by clinical research staff each have advantages in efficiency. Web-based adverts had the lowest cost per person recruited (£13.41 per person recruited). Specialised care referral cost £183.24 per person, non-web-based adverts cost £372.03 per patient and recruitment via primary care cost £407.65 for each patient. Financial incentives, abridged questionnaires and pre-notification had a positive effect on retention rates. CONCLUSION The recruitment studies included showed differences in strategies, clinical settings, mental health conditions and study design. It is difficult to assess the overall effectiveness of any particular recruitment strategy as some strategies that worked well for a particular population may not work as well for others. Paying attention to the accessibility of information and consent materials may help improve recruitment. More research in this area is needed given its important implications.
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Affiliation(s)
- Yifeng Liu
- Research Department of Primary Care and Population Health, University College London, London, United Kingdom
| | - Emma Pencheon
- Chelsea and Westminster NHS Foundation Trust, London, United Kingdom
| | - Rachael Maree Hunter
- Research Department of Primary Care and Population Health, University College London, London, United Kingdom
| | - Joanna Moncrieff
- Division of Psychiatry, University College London, London, United Kingdom
| | - Nick Freemantle
- Institute of Clinical Trials and Methodology, University College London, London, United Kingdom
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Girgis RR, Ciarleglio A, Choo T, Haynes G, Bathon JM, Cremers S, Kantrowitz JT, Lieberman JA, Brown AS. A Randomized, Double-Blind, Placebo-Controlled Clinical Trial of Tocilizumab, An Interleukin-6 Receptor Antibody, For Residual Symptoms in Schizophrenia. Neuropsychopharmacology 2018; 43:1317-1323. [PMID: 29090685 PMCID: PMC5916349 DOI: 10.1038/npp.2017.258] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 10/01/2017] [Accepted: 10/24/2017] [Indexed: 01/16/2023]
Abstract
Evidence from preclinical, epidemiological, and human studies indicates that inflammation, and in particular elevated interleukin-6 (IL-6) activity, may be related to clinical manifestations and pathophysiology of schizophrenia. Furthermore, studies in preclinical models suggest that decreasing IL-6 activity may mitigate or reverse some of these deficits. The purpose of this trial was to test whether an IL-6 receptor antibody, tocilizumab, would improve residual positive and negative symptoms and cognitive deficits in schizophrenia. We randomized 36 clinically stable, moderately symptomatic (i.e., Positive and Negative Syndrome Scale (PANSS) >60) individuals with schizophrenia to 3 monthly infusions of 8 mg/kg tocilizumab or placebo (normal saline). The primary outcome was effect at week 12 on the PANSS Total Score. Effects on the MATRICS, other PANSS subscales, Clinical Global Impression, and Global Assessment of Functioning were secondary outcomes. There were no observed treatment effects on any behavioral outcome measure. Baseline C-reactive protein (CRP) or cytokine levels did not predict treatment outcome, nor were there correlations between changes in these inflammatory markers and the measured outcomes. As expected, IL-6 and IL-8 increased, while CRP decreased, in the tocilizumab group compared with the placebo group. This study did not reveal any evidence that an IL-6 receptor antibody affects behavioral outcomes in schizophrenia. One potential explanation is the lack of capacity of this agent to penetrate the central nervous system. Additional trials of medications aimed at targeting cytokine overactivity that act directly on brain function and/or treatment in early-stage psychosis populations are needed.
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Affiliation(s)
- Ragy R Girgis
- Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY, USA,New York State Psychiatric Institute, New York, NY, USA,Department of Psychiatry, Columbia University College of Physicians and Surgeons, 1051 Riverside Drive, Unit 31, New York 10032, NY, USA. Tel: +1 646 774 5553; Fax: +1 646 774 5237; E-mail:
| | - Adam Ciarleglio
- Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY, USA,New York State Psychiatric Institute, New York, NY, USA
| | - Tse Choo
- Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY, USA,New York State Psychiatric Institute, New York, NY, USA
| | - Gregory Haynes
- Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY, USA,New York State Psychiatric Institute, New York, NY, USA
| | - Joan M Bathon
- Department of Medicine, Columbia University, New York, NY, USA
| | - Serge Cremers
- Department of Pathology, Columbia University, New York, NY, USA
| | - Joshua T Kantrowitz
- Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY, USA,New York State Psychiatric Institute, New York, NY, USA,Schizophrenia Research Center, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA
| | - Jeffrey A Lieberman
- Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY, USA,New York State Psychiatric Institute, New York, NY, USA
| | - Alan S Brown
- Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY, USA,New York State Psychiatric Institute, New York, NY, USA
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Hasnain M, Rudnick A, Bonnell WS, Remington G, Lam RW. Use of Placebo in Clinical Trials of Psychotropic Medication. CANADIAN JOURNAL OF PSYCHIATRY. REVUE CANADIENNE DE PSYCHIATRIE 2018; 63:338-341. [PMID: 29668328 PMCID: PMC5912304 DOI: 10.1177/0706743717752917] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This position paper has been substantially revised by the Canadian Psychiatric Association's Research Committee and approved for republication by the CPA's Board of Directors on March 31, 2017. The original position paper1 was developed by the Scientific and Research Council and approved by the Board of Directors on October 4, 1996.
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Affiliation(s)
- Mehrul Hasnain
- 1 Associate Professor, Discipline of Psychiatry, Memorial University of Newfoundland, St. John's, Newfoundland
| | - Abraham Rudnick
- 2 Professor, Section of Psychiatry, Northern Ontario School of Medicine, Lakehead and Laurentian Universities, Thunder Bay and Sudbury, Ontario; Vice-President and Chief of Psychiatry, Thunder Bay Regional Health Sciences Centre, Thunder Bay, Ontario; Chief Scientist, Thunder Bay Regional Health Research Institute, Thunder Bay, Ontario
| | - Weldon S Bonnell
- 3 Associate Professor, Discipline of Psychiatry, Memorial University of Newfoundland, St. John's, Newfoundland
| | - Gary Remington
- 4 Professor, Departments of Psychiatry and Psychological Clinical Science, Faculty of Medicine, University of Toronto; Chief, Schizophrenia Division, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario
| | - Raymond W Lam
- 5 Professor and BC Leadership Chair in Depression Research, Department of Psychiatry, University of British Columbia; Director, Mood Disorders Centre, Djavad Mowafaghian Centre for Brain Health, Vancouver, British Columbia
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Hasan A, Strube W, Palm U, Wobrock T. Repetitive Noninvasive Brain Stimulation to Modulate Cognitive Functions in Schizophrenia: A Systematic Review of Primary and Secondary Outcomes. Schizophr Bull 2016; 42 Suppl 1:S95-S109. [PMID: 27460623 PMCID: PMC4960427 DOI: 10.1093/schbul/sbv158] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Despite many years of research, there is still an urgent need for new therapeutic options for the treatment of cognitive deficits in schizophrenia. Noninvasive brain stimulation (NIBS) has been proposed to be such a novel add-on treatment option. The main objective of this review was to systematically evaluate the cognitive effects of repetitive NIBS in schizophrenia. As most studies have not been specifically designed to investigate cognition as primary outcome, we have focused on both, primary and secondary outcomes. The PubMed/MEDLINE database (1985-2015) was systematically searched for interventional studies investigating the effects of repetitive NIBS on schizophrenia symptoms. All interventional clinical trials using repetitive transcranial stimulation, transcranial theta burst stimulation, and transcranial direct current stimulation for the treatment of schizophrenia were extracted and analyzed with regard to cognitive measures as primary or secondary outcomes. Seventy-six full-text articles were assessed for eligibility of which 33 studies were included in the qualitative synthesis. Of these 33 studies, only 4 studies included cognition as primary outcome, whereas 29 studies included cognitive measures as secondary outcomes. A beneficial effect of frontal NIBS could not be clearly established. No evidence for a cognitive disruptive effect of NIBS (temporal lobe) in schizophrenia could be detected. Finally, a large heterogeneity between studies in terms of inclusion criteria, stimulation parameters, applied cognitive measures, and follow-up intervals was observed. This review provides the first systematic overview regarding cognitive effects of repetitive NIBS in schizophrenia.
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Affiliation(s)
- Alkomiet Hasan
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Germany;
| | - Wolfgang Strube
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Germany
| | - Ulrich Palm
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Germany
| | - Thomas Wobrock
- County Hospitals Darmstadt-Dieburg, Groß-Umstadt, Germany; Department of Psychiatry and Psychotherapy, Georg-August-University, Göttingen, Germany
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Rutherford BR, Pott E, Tandler JM, Wall MM, Roose SP, Lieberman JA. Placebo response in antipsychotic clinical trials: a meta-analysis. JAMA Psychiatry 2014; 71:1409-21. [PMID: 25321611 PMCID: PMC4256120 DOI: 10.1001/jamapsychiatry.2014.1319] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
IMPORTANCE Because increasing placebo response rates decrease drug-placebo differences and increase the number of failed trials, it is imperative to determine what is causing this trend. OBJECTIVES To investigate the relationship between antipsychotic medication and placebo response by publication year, and to identify associated study design and implementation variables. DATA SOURCES MEDLINE, PsycINFO, and PubMed were searched to identify randomized clinical trials of antipsychotic medications published from 1960 to July 2013. STUDY SELECTION Included were randomized clinical trials lasting 4 to 24 weeks, contrasting antipsychotic medication with placebo or an active comparator, and enrolling patients 18 years of age or older with schizophrenia or schizoaffective disorder. DATA EXTRACTION AND SYNTHESIS Standardized mean change scores were calculated for each treatment arm, plotted against publication year, and tested with Spearman rank correlation coefficients. Hierarchical linear modeling identified factors associated with the standardized mean change across medication and placebo treatment arms. MAIN OUTCOMES AND MEASURES We hypothesized that the mean change in placebo-treated patients would significantly increase from 1960 to the present, that a greater change would be observed in active comparator vs placebo-controlled trials, and that more protocol visits would increase the symptom change observed. RESULTS In the 105 trials examined, the mean change observed in placebo arms increased significantly with year of publication (n=39, r=0.52, P=.001), while the mean change in effective dose medication arms decreased significantly (n=208, r=-0.26, P<.001). Significant interactions were found between assignment to effective dose medication and publication year (t260=-5.55, P<.001), baseline severity (t260=5.08, P<.001), and study duration (t260=-3.76, P<.001), indicating that the average drug-placebo difference significantly decreased over time, with decreasing baseline severity and with increasing study duration. Medication treatment in comparator studies was associated with significantly more improvement than medication treatment in placebo-controlled trials (t93=2.73, P=.008). CONCLUSIONS AND RELEVANCE The average treatment change associated with placebo treatment in antipsychotic trials increased since 1960, while the change associated with medication treatment decreased. Changes in randomized clinical trials leading to inflation of baseline scores, enrollment of less severely ill participants, and higher expectations of patients may all be responsible.
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Affiliation(s)
- Bret R Rutherford
- Columbia University College of Physicians and Surgeons, New York State Psychiatric Institute ,1051 Riverside Drive, Box 98, New York, NY 10032, 646 774 8660 (telephone)
| | | | | | - Melanie M. Wall
- Columbia University College of Physicians and Surgeons, New York State Psychiatric Institute
| | - Steven P. Roose
- Columbia University College of Physicians and Surgeons, New York State Psychiatric Institute
| | - Jeffrey A. Lieberman
- Columbia University College of Physicians and Surgeons, New York State Psychiatric Institute
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Lindheimer JB, Loy BD, O'Connor PJ. Short-term effects of black pepper (Piper nigrum) and rosemary (Rosmarinus officinalis and Rosmarinus eriocalyx) on sustained attention and on energy and fatigue mood states in young adults with low energy. J Med Food 2013; 16:765-71. [PMID: 23905652 DOI: 10.1089/jmf.2012.0216] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The purpose was to test whether a single dose of black pepper or rosemary produced short-term enhancements in sustained attention, motivation to perform cognitive tasks, or feelings of mental energy and fatigue. Outcomes were measured in 40 young adults with below average feelings of energy before and twice after they orally consumed capsules containing either black pepper (2.0 g), rosemary (1.7 g), or a placebo (3.1 g rice flour). Sustained attention was measured using a 16-min dual task, in which, single-digit numbers were presented every second on a screen and the participant performed both a primary task [detection of three successive, different odd digits] and a secondary task [detection of the number 6]. Feelings of energy and fatigue were measured using the vigor and fatigue subscales of the Profile of Mood States and visual analog scales (VAS). Analysis of variance showed nonsignificant condition (spice versus placebo)×time (T1, T2, & T3) effects for motivation, measured with a VAS, and the intensity of energy and fatigue feelings. Unadjusted effect sizes revealed that rosemary induced small, transient reductions in false alarm errors (d=0.21) and mental fatigue (d=0.40) at isolated time periods. Time-varying analysis of covariance, controlling for motivation to perform cognitive tasks, showed no significant effects on the primary or secondary task outcomes of correct responses (hits), errors (false alarms, misses), speed of response (reaction time), and signal detection sensitivity. It is concluded that black pepper and rosemary, consumed in a capsule form, in the doses used and while wearing a nose clip to block olfactory effects, do not induce consistent short-term improvements in sustained attention, motivation to perform cognitive tasks, or feelings of mental energy and fatigue in young adults with low energy.
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Affiliation(s)
- Jacob B Lindheimer
- Department of Kinesiology, University of Georgia, Athens, Georgia 30602-6554, USA
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Genetic biomarkers of placebo response: what could it mean for future trial design? ACTA ACUST UNITED AC 2013; 3:311-314. [PMID: 24049631 DOI: 10.4155/cli.13.8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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de Araújo AN, de Sena EP, de Oliveira IR, Juruena MF. Antipsychotic agents: efficacy and safety in schizophrenia. Drug Healthc Patient Saf 2012; 4:173-80. [PMID: 23236256 PMCID: PMC3516452 DOI: 10.2147/dhps.s37429] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Indexed: 02/05/2023] Open
Abstract
Antipsychotics have provided a great improvement in the management of people with schizophrenia. The first generation antipsychotics could establish the possibility of managing many psychotic subjects in an outpatient setting. With the advent of the second (SGA) and third generation antipsychotics (TGA), other psychiatric disorders such as bipolar depression, bipolar mania, autism, and major depressive disorder have now been approved for the use of these drugs for their treatment. Also, the administration of more specific assessment tools has allowed for better delineation of the repercussions of these drugs on symptoms and the quality of life of patients who use antipsychotic agents. In general, the SGA share similar mechanisms of action to achieve these results: dopamine-2 receptor antagonism plus serotonin-2A receptor antagonism. The TGA (eg, aripiprazole) have partial agonist activity at the dopamine-2 receptor site, and are also called dopaminergic stabilizers. The pharmacological profile of SGA and TGA may provide better efficacy against negative symptoms, and are less likely to produce extrapyramidal symptoms; however, the SGA and TGA are associated with many other adverse events. The clinician has to balance the risks and benefits of these medications when choosing an antipsychotic for an individual patient.
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Affiliation(s)
| | - Eduardo Pondé de Sena
- Postgraduation Program in Interactive Processes of Organs and Systems
- Department of Pharmacology, Institute of Health Sciences
- Correspondence: Eduardo Pondé de Sena, Department of Pharmacology, Institute of Health Sciences, Federal University of Bahia, Avenida Reitor Miguel Calmon, s/n, Vale do Canela, Salvador, Bahia, CEP 40110-100, Brazil, Tel +55 713 241 7154, Fax +55 713 241 7154, Email
| | - Irismar Reis de Oliveira
- Postgraduation Program in Interactive Processes of Organs and Systems
- Department of Neurosciences and Mental Health, School of Medicine, Federal University of Bahia, Salvador, Brazil
| | - Mario F Juruena
- Stress and Affective Disorders Program, Department of Neuroscience and Behavior, Faculty of Medicine of Ribeirao Preto, University of Sao Paulo, Sao Paulo, Brazil
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Field JR, Walker AG, Conn PJ. Targeting glutamate synapses in schizophrenia. Trends Mol Med 2011; 17:689-98. [PMID: 21955406 DOI: 10.1016/j.molmed.2011.08.004] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Revised: 08/12/2011] [Accepted: 08/19/2011] [Indexed: 12/25/2022]
Abstract
Although early clinical observations implicated dopamine dysfunction in the neuropathology of schizophrenia, accumulating evidence suggests that multiple neurotransmitter pathways are dysregulated. The psychotomimetic actions of NMDA receptor antagonists point to an imbalance of glutamatergic signaling. Encouragingly, numerous preclinical and clinical studies have elucidated several potential targets for increasing NMDA receptor function and equilibrating glutamatergic tone, including the metabotropic glutamate receptors 2, 3 and 5, the muscarinic acetylcholine receptors M(1) and M(4), and the glycine transporter GlyT1. Highly specific allosteric and orthosteric ligands have been developed that modify the activity of these novel target proteins, and in this review we summarize both the glutamatergic mechanisms and the novel compounds that are increasing the promise for a multifaceted pharmacological approach to treat schizophrenia.
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Affiliation(s)
- Julie R Field
- Department of Pharmacology and Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, TN 37212, USA
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