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Devinsky O, Hyland K, Loftus R, Nortvedt C, Nabbout R. Placebo response in patients with Dravet syndrome: Post-hoc analysis of two clinical trials. Epilepsy Behav 2024; 156:109805. [PMID: 38677101 DOI: 10.1016/j.yebeh.2024.109805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 04/18/2024] [Accepted: 04/18/2024] [Indexed: 04/29/2024]
Abstract
OBJECTIVE Dravet syndrome is a rare, early childhood-onset epileptic and developmental encephalopathy. Responses to placebo in clinical trials for epilepsy therapies range widely, but factors influencing placebo response remain poorly understood. This study explored placebo response and its effects on safety, efficacy, and quality of life outcomes in patients with Dravet syndrome. METHODS We performed exploratory post-hoc analyses of pooled data from placebo-treated patients from the GWPCARE 1B and GWPCARE 2 randomized controlled phase III trials, comparing cannabidiol and matched placebo in 2-18 year old Dravet syndrome patients. All patients had ≥4 convulsive seizures during a baseline period of 4 weeks. RESULTS 124 Dravet syndrome-treated patients were included in the analysis (2-5 years: n = 35; 6-12 years: n = 52; 13-18 years: n = 37). Convulsive seizures were experienced by all placebo group patients at all timepoints, with decreased median convulsive seizure frequency during the treatment period versus baseline; the number of convulsive seizure-free days was similar to baseline. Convulsive seizure frequency had a nominally significant positive correlation with age and a nominally significant negative correlation with body mass index. Most placebo-treated patients experienced a treatment-emergent adverse event; however, most resolved quickly, and serious adverse events were infrequent. Placebo treatment had very little effect on reported Caregiver Global Impression of Change outcomes versus baseline. INTERPRETATION Placebo had little impact on convulsive seizure-free days and Caregiver Global Impression of Change versus baseline, suggesting that these metrics may help differentiate placebo and active treatment effects in future studies. However, future research should further assess placebo responses to confirm these results.
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Affiliation(s)
- Orrin Devinsky
- Department of Neurology, New York University Grossman School of Medicine, New York, NY, USA
| | | | | | | | - Rima Nabbout
- Department of Pediatric Neurology, Necker Enfants Malades Hospital, APHP, Reference Centre for Rare Epilepsies and Member of the ERN EpiCARE, Imagine Institute UMR1163, Université Paris Cité, Paris, France
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Ooghe A, Liu X, Robbins S, Eyles JP, Deveza LA, Branders S, Clermont F, Pereira A, Hunter DJ. Report of similar placebo response in one internet versus onsite randomised controlled trials from the literature. OSTEOARTHRITIS AND CARTILAGE OPEN 2024; 6:100474. [PMID: 38737983 PMCID: PMC11088186 DOI: 10.1016/j.ocarto.2024.100474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 04/23/2024] [Indexed: 05/14/2024] Open
Abstract
Objective The aim of this study was to compare the magnitude and the predictors of the placebo response in an internet versus onsite randomised controlled trials (RCTs) in people with hand osteoarthritis (HOA). Method This study is a post-hoc analysis based on one internet RCT (RADIANT) and previously published onsite RCTs for HOA identified through a rigorous searching and selection strategy. The magnitude of the placebo response in the two different types of RCTs were compared using heterogeneity statistics and forest plots visualisation. Classic placebo predictors as well as a combined model, defined with data from onsite RCTs, were tested to predict the placebo response. Results We analysed the dataset from RADIANT and fourteen previously published onsite RCTs. None of the analyses showed a significant difference between the placebo response for the internet versus onsite RCTs. The "classic" placebo predictors combined in a multivariate predictive model correlated significantly with the placebo response measured in RADIANT study. Conclusion Despite the absence of face-to-face interactions with the study personnel, there is no evidence that either the magnitude or the predictors of the placebo response of this internet RCT differ from those of onsite RCTs. This analysis is considered as a first step towards evaluating the difference between these designs and strengthens the argument that internet RCTs remain an acceptable alternative way to assess the efficacy of an active treatment in comparison to a placebo.
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Affiliation(s)
- Arthur Ooghe
- Cognivia, 11 rue Granbonpré, Bte 9 - 1435 Mont-Saint-Guibert, Belgium
| | - Xiaoqian Liu
- Rheumatology Department, Royal North Shore Hospital, Northern Clinical School, Faculty of Medicine and Health, The University of Sydney, Australia
- Sydney Musculoskeletal Health, Kolling Institute, The University of Sydney, Australia
| | - Sarah Robbins
- Rheumatology Department, Royal North Shore Hospital, Northern Clinical School, Faculty of Medicine and Health, The University of Sydney, Australia
- Sydney Musculoskeletal Health, Kolling Institute, The University of Sydney, Australia
| | - Jillian P. Eyles
- Rheumatology Department, Royal North Shore Hospital, Northern Clinical School, Faculty of Medicine and Health, The University of Sydney, Australia
- Sydney Musculoskeletal Health, Kolling Institute, The University of Sydney, Australia
| | - Leticia A. Deveza
- Rheumatology Department, Royal North Shore Hospital, Northern Clinical School, Faculty of Medicine and Health, The University of Sydney, Australia
- Sydney Musculoskeletal Health, Kolling Institute, The University of Sydney, Australia
| | - Samuel Branders
- Cognivia, 11 rue Granbonpré, Bte 9 - 1435 Mont-Saint-Guibert, Belgium
| | - Frédéric Clermont
- Cognivia, 11 rue Granbonpré, Bte 9 - 1435 Mont-Saint-Guibert, Belgium
| | - Alvaro Pereira
- Cognivia, 11 rue Granbonpré, Bte 9 - 1435 Mont-Saint-Guibert, Belgium
| | - David J. Hunter
- Rheumatology Department, Royal North Shore Hospital, Northern Clinical School, Faculty of Medicine and Health, The University of Sydney, Australia
- Sydney Musculoskeletal Health, Kolling Institute, The University of Sydney, Australia
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Patel E, Ramaiah P, Mamaril-Davis JC, Bauer IL, Koujah D, Seideman T, Kelbert J, Nosova K, Bina RW. Outcome differences between males and females undergoing deep brain stimulation for treatment-resistant depression: systematic review and individual patient data meta-analysis. J Affect Disord 2024; 351:481-488. [PMID: 38296058 DOI: 10.1016/j.jad.2024.01.251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 01/22/2024] [Accepted: 01/26/2024] [Indexed: 02/06/2024]
Abstract
BACKGROUND Treatment-resistant depression (TRD) occurs more commonly in women. Deep brain stimulation (DBS) is an emerging treatment for TRD, and its efficacy continues to be explored. However, differences in treatment outcomes between males and females have yet to be explored in formal analysis. METHODS A PRISMA-compliant systematic review of DBS for TRD studies was conducted. Patient-level data were independently extracted by two authors. Treatment response was defined as a 50 % or greater reduction in depression score. Percent change in depression scores by gender were evaluated using random-effects analyses. RESULTS Of 737 records, 19 studies (129 patients) met inclusion criteria. The mean reduction in depression score for females was 57.7 % (95 % CI, 64.33 %-51.13 %), whereas for males it was 35.2 % (95 % CI, 45.12 %-25.23 %) (p < 0.0001). Females were more likely to respond to DBS for TRD when compared to males (OR = 2.44, 95 % CI 1.06, 1.95). These differences varied in significance when stratified by DBS anatomical target, age, and timeframe for responder classification. LIMITATIONS Studies included were open-label trials with small sample sizes. CONCLUSIONS Our findings suggest that females with TRD respond at higher rates to DBS treatment than males. Further research is needed to elucidate the implications of these results, which may include connectomic sexual dimorphism, depression phenotype variations, or unrecognized symptom reporting differences. Methodological standardization of outcome scales, granular demographic data, and individual subject outcomes would allow for more robust comparisons between trials.
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Affiliation(s)
- Ekta Patel
- University of Arizona College of Medicine - Phoenix, Phoenix, AZ, USA
| | - Priya Ramaiah
- University of Arizona College of Medicine - Phoenix, Phoenix, AZ, USA
| | | | - Isabel L Bauer
- University of Arizona College of Medicine - Phoenix, Phoenix, AZ, USA
| | - Dalia Koujah
- University of Arizona College of Medicine - Phoenix, Phoenix, AZ, USA
| | - Travis Seideman
- University of Arizona College of Medicine - Phoenix, Phoenix, AZ, USA
| | - James Kelbert
- University of Arizona College of Medicine - Phoenix, Phoenix, AZ, USA
| | - Kristin Nosova
- Department of Neurosurgery, Banner University Medical Center/University of Arizona College of Medicine - Phoenix, Phoenix, AZ, USA
| | - Robert W Bina
- Department of Neurosurgery, Banner University Medical Center/University of Arizona College of Medicine - Phoenix, Phoenix, AZ, USA.
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Schaefer M, Enge S. Open-label placebos enhance test performance and reduce anxiety in learner drivers: a randomized controlled trial. Sci Rep 2024; 14:6684. [PMID: 38509101 PMCID: PMC10954622 DOI: 10.1038/s41598-024-56600-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Accepted: 03/08/2024] [Indexed: 03/22/2024] Open
Abstract
Passing the driving school test can be very challenging, especially in big cities, where up to 52% of all students fail this test. Consequently, many learner drivers experience stress and anxiety. For some learner drivers these feelings can be extreme and negatively affect the performance in the driving test. Different strategies to face anxiety and stress are known, including, for example, psychological or pharmacological approaches and even placebo pills. Recent intriguing findings have also demonstrated that placebos without deception, so-called open-label placebos, successfully reduce anxiety. Here we aimed to test effects of this novel treatment for learner drivers. We investigated whether open-label placebos affect test performance and feelings of anxiety in learner drivers. Sixty-eight healthy participants (mean age 21.94 years, 26 females) were randomized into two groups. The open-label placebo group received placebo pills two weeks before the driving test (two pills each day). The control group received no treatment. Results revealed that the open-label placebo group experienced significantly less anxiety than the control group before the test (measured with the State-Trait-Anxiety-Inventory, STAI-S, and the German Test Anxiety Inventory, PAF). Moreover, in the open-label placebo group less learner drivers failed the driving test (29.41% vs. 52.95%). The results suggest that open-label placebos may provide an ethical unproblematic way to experience less anxiety and might also enhance the probability to pass the driving test. We discuss possible mechanisms of open-label placebos and limitations of our findings.
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Affiliation(s)
| | - Sören Enge
- Medical School Berlin, 12247, Berlin, Germany
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5
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Wang S, Xiong Z, Cui Y, Fan F, Zhang S, Jia R, Hu Y, Li L, Zhang X, Han F. Placebo and Nocebo Responses in Pharmacological Trials of Tic Disorders: A Meta-Analysis. Mov Disord 2024; 39:585-595. [PMID: 38247265 DOI: 10.1002/mds.29714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 12/20/2023] [Accepted: 12/22/2023] [Indexed: 01/23/2024] Open
Abstract
BACKGROUND Clinical trials of new drugs for tic disorders (TD) often fail to yield positive results. Placebo and nocebo responses play a vital role in interpreting the outcomes of randomized controlled trials (RCTs), yet these responses in RCTs of TD remain unexplored. OBJECTIVE The aim was to assess the magnitude of placebo and nocebo responses in RCTs of pharmacological interventions for TD and identify influencing factors. METHODS A systematic search of the Embase, Medline, Cochrane Central Register of Controlled Trials, and PsycINFO databases was conducted. Eligible studies were RCTs that compared active pharmacological agents with placebos. Placebo response was defined as the change from baseline in TD symptom severity in the placebo group, and nocebo response as the proportion experiencing adverse events (AEs) in this group. Subgroup analysis and meta-regression were performed to explore modifying factors. RESULTS Twenty-four trials involving 2222 participants were included in this study. A substantial placebo response in TD symptom severity was identified, with a pooled effect size of -0.79 (95% confidence interval [CI] -0.99 to -0.59; I2 = 67%). Forty-four percent (95% CI 27% to 63%; I2 = 92%) of patients experienced AEs while taking inert pills. Sample size, study design, and randomization ratio were correlated with changes in placebo and nocebo responses. CONCLUSION There were considerable placebo and nocebo responses in TD clinical trials. These results are of great relevance for the design of future trials and for clinical practice in TD. SYSTEMATIC REVIEW REGISTRATION PROSPERO registration ID CRD42023388397. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Simeng Wang
- Department of Pediatrics, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Zhiyi Xiong
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Yuehua Cui
- Department of Pediatrics, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Fei Fan
- Department of Pediatrics, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Si Zhang
- Department of Pediatrics, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Ru Jia
- Department of Pediatrics, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Yuchen Hu
- Department of Pediatrics, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Liang Li
- Department of Traditional Chinese Medicine, Children's Hospital of Soochow University, Soochow, China
| | - Xuan Zhang
- Chinese EQUATOR Center, Hong Kong Chinese Medicine Clinical Study Center, Chinese Clinical Trial Registry (Hong Kong), School of Chinese Medicine, Hong Kong Baptist University, Kowloon, Hong Kong SAR, China
| | - Fei Han
- Department of Pediatrics, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
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Taniguchi AN, Sutton SR, Mills JF, Nguyen SA, Rizk HG, Meyer TA, Nguyen JP, Lambert PR. Placebo effect in randomized controlled trials for Meniere's disease: A meta-analysis. Am J Otolaryngol 2024; 45:104178. [PMID: 38101129 DOI: 10.1016/j.amjoto.2023.104178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Accepted: 12/06/2023] [Indexed: 12/17/2023]
Abstract
PURPOSE Meniere's Disease is a condition known for its recurrent vertigo, fluctuating sensorineural hearing loss, aural fullness, and tinnitus. Previous studies have demonstrated significant influence of placebo treatments. Our objective was to quantify the magnitude of the placebo effect in randomized controlled trials for Meniere's Disease. MATERIALS AND METHODS A systematic review was performed by searching PubMed, SCOPUS, CINAHL, and Cochrane databases from inception through September 27, 2022. Data extraction, quality rating, and risk of bias assessment were performed by two independent reviewers. A meta-analysis of mean differences with 95 % confidence interval, weighted summary proportions, and proportion differences were calculated using random and fixed effects models. RESULTS A total of 15 studies (N = 892) were included in the review. Significant improvement was seen in the functional level scores of the pooled placebo groups, with a mean difference of -0.6 points, (95%CI: -1.2 to -0.1). There was no difference in pure tone audiometry, speech discrimination score, or vertigo frequency at 1 and 3 months for the placebo group. Patient-reported vertigo episodes were improved in 52.5 % (95%CI: 39.2 to 65.5) of the placebo group and was significantly less than the pooled experimental group (90.1 %, 95%CI: 39.2 to 65.5, p < 0.001). CONCLUSIONS The placebo effect in Meniere's Disease trials is associated with some symptomatic improvement in subjective outcomes, such as patient reported vertigo episodes. However, the clinical significance is questionable across other outcomes measures, especially when analyzing objective data. The extent and strength of the placebo effect continues to be a hurdle in the search for better treatment options.
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Affiliation(s)
- April N Taniguchi
- Department of Otolaryngology - Head and Neck Surgery, Medical University of South Carolina, 135 Rutledge Avenue, Charleston, SC 29425, USA; University of Central Florida, College of Medicine, 6850 Lake Nona Blvd, Orlando, FL 32827, USA
| | - Sarah R Sutton
- Department of Otolaryngology - Head and Neck Surgery, Medical University of South Carolina, 135 Rutledge Avenue, Charleston, SC 29425, USA; University of Nevada, Reno School of Medicine, 1664 N Virginia St, Reno, NV 89557, USA
| | - John F Mills
- Department of Otolaryngology - Head and Neck Surgery, Medical University of South Carolina, 135 Rutledge Avenue, Charleston, SC 29425, USA
| | - Shaun A Nguyen
- Department of Otolaryngology - Head and Neck Surgery, Medical University of South Carolina, 135 Rutledge Avenue, Charleston, SC 29425, USA.
| | - Habib G Rizk
- Department of Otolaryngology - Head and Neck Surgery, Medical University of South Carolina, 135 Rutledge Avenue, Charleston, SC 29425, USA
| | - Ted A Meyer
- Department of Otolaryngology - Head and Neck Surgery, Medical University of South Carolina, 135 Rutledge Avenue, Charleston, SC 29425, USA
| | | | - Paul R Lambert
- Department of Otolaryngology - Head and Neck Surgery, Medical University of South Carolina, 135 Rutledge Avenue, Charleston, SC 29425, USA
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Viglione V, Boffa A, Previtali D, Vannini F, Faldini C, Filardo G. The 'placebo effect' in the conservative treatment of plantar fasciitis: a systematic review and meta-analyses. EFORT Open Rev 2023; 8:719-730. [PMID: 37787480 PMCID: PMC10562949 DOI: 10.1530/eor-23-0082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/04/2023] Open
Abstract
Purpose The study of the placebo effect is key to elucidate the 'real effect' of conservative interventions for plantar fasciitis. The aim of this meta-analysis was to quantify the impact of placebo in the different conservative treatments of plantar fasciitis. Methods A systematic literature review was performed on double-blind placebo-controlled trials (RCTs) according to PRISMA guidelines on PubMed, Embase, and Web of Science. The meta-analysis primary outcome was the 0-10 pain variation after placebo treatments analyzed at 1 week, 1, 3, 6, and 12 months. The risk of bias was assessed using the RoB 2.0 tool, while the overall quality of evidence was graded according to the GRADE guidelines. Results The placebo effect for conservative treatments was studied in 42 double-blind RCTs on 1724 patients. The meta-analysis of VAS pain showed a statistically significant improvement after placebo administration of 2.13/10 points (P < 0.001), being highest at 12 months with 2.79/10 points (P < 0.001). The improvement of the placebo groups was higher in the extracorporeal shock wave therapy studies compared to the injection studies (2.59 vs 1.78; P = 0.05). Eight studies had a low risk of bias, 23 studies had 'some concerns,' and 4 studies had a high risk of bias. The GRADE evaluation showed an overall high quality of evidence. Conclusion This systematic review and meta-analysis demonstrated that the placebo effect represents an important component of all conservative approaches to treat plantar fasciitis. This effect is statistically and clinically significant, increases over time, and depends on the type of conservative treatment applied to address plantar fasciitis.
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Affiliation(s)
- Valentina Viglione
- Clinica Ortopedica e Traumatologica 1 IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Angelo Boffa
- Applied and Translational Research (ATR) Center, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Davide Previtali
- Department of Surgery, EOC, Service of Orthopaedics and Traumatology, Lugano, Switzerland
| | - Francesca Vannini
- Clinica Ortopedica e Traumatologica 1 IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Cesare Faldini
- Clinica Ortopedica e Traumatologica 1 IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Giuseppe Filardo
- Applied and Translational Research (ATR) Center, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
- Department of Surgery, EOC, Service of Orthopaedics and Traumatology, Lugano, Switzerland
- Faculty of Biomedical Sciences, Università della Svizzera Italiana, Lugano, Switzerland
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Tobe R, Zhu Y, Gleissl T, Rossomanno S, Veenstra-VanderWeele J, Smith J, Hollander E. Predictors of placebo response in three large clinical trials of the V1a receptor antagonist balovaptan in autism spectrum disorder. Neuropsychopharmacology 2023:10.1038/s41386-023-01573-9. [PMID: 37045991 PMCID: PMC10267133 DOI: 10.1038/s41386-023-01573-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 03/16/2023] [Accepted: 03/21/2023] [Indexed: 04/14/2023]
Abstract
High rates of placebo response are increasingly implicated in failed autism spectrum disorder (ASD) clinical trials. Despite this, there are limited investigations of placebo response in ASD. We sought to identify baseline predictors of placebo response and quantify their influence on clinical scales of interest for three harmonized randomized clinical trials of balovaptan, a V1a receptor antagonist. We employed a two-step approach to identify predictors of placebo response on the Vineland-II two-domain composite (2DC) (primary outcome and a caregiver measure) and Clinical Global Impression (CGI) scale (secondary outcome and a clinician measure). The initial candidate predictor set of variables pertained to participant-level, site-specific, and protocol-related factors. Step 1 aimed to identify influential predictors of placebo response using Least Absolute Shrinkage and Selection Operator (LASSO) regression, while Step 2 quantified the influence of predictors via linear regression. Results were validated through statistical bootstrapping approaches with 500 replications of the analysis dataset. The pooled participant-level dataset included individuals with ASD aged 5 to 62 years (mean age 21 [SD 10]), among which 263 and 172 participants received placebo at Weeks 12 and 24, respectively. Although no influential predictors were identified for CGI, findings for Vineland-II 2DC are robust and informative. Decreased placebo response was predicted by higher baseline Vineland-II 2DC (i.e., more advanced adaptive function), longer trial duration, and European (vs United States) sites, while increased placebo response was predicted by commercial (vs academic) sites, attention deficit hyperactivity disorder and depression. Identification of these factors may be useful in anticipating and mitigating placebo response in drug development efforts in ASD and across developmental and psychiatric conditions.
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Affiliation(s)
- Russell Tobe
- Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY, USA.
| | - Yajing Zhu
- F. Hoffmann-La Roche Ltd., Welwyn Garden City, UK
| | | | | | - Jeremy Veenstra-VanderWeele
- Department of Psychiatry, Columbia University, New York, NY, USA
- New York State Psychiatric Institute, New York, NY, USA
| | - Janice Smith
- F. Hoffmann-La Roche Ltd., Welwyn Garden City, UK
| | - Eric Hollander
- Department of Psychiatry and Behavioral Sciences and Albert Einstein College of Medicine, New York, NY, USA
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Colloca L, Dworkin RH, Farrar JT, Tive L, Yang J, Viktrup L, Dasic G, West CR, Whalen E, Brown MT, Gilbert SA, Verburg KM. Predicting Treatment Responses in Patients With Osteoarthritis: Results From Two Phase III Tanezumab Randomized Clinical Trials. Clin Pharmacol Ther 2023; 113:878-886. [PMID: 36621827 PMCID: PMC11000258 DOI: 10.1002/cpt.2842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 12/21/2022] [Indexed: 01/10/2023]
Abstract
Prediction of treatment responses is essential to move forward translational science. Our question was to identify patient-based variables that predicted responses to treatments. We conducted secondary analyses on pooled data from two randomized phase III clinical trials (NCT02697773 and NCT02709486) conducted in participants with moderate to severe osteoarthritis randomized to subcutaneous placebo (n = 514) or tanezumab 2.5 mg (n = 514). We used gradient boosted regression trees to identify variables that predicted Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain subscale scores at Week 16 and marginal plots to determine the directional relationship between each variable category and responses to placebo or tanezumab within the models. We also used Virtual Twins models to identify potential subgroups of response to the active treatment vs. placebo. We found that responses to placebo were predicted by baseline WOMAC Physical Function, baseline WOMAC Pain, the radiographic classification of the index joint, and the standard deviation of diary pain scores at baseline. In contrast, baseline WOMAC Pain along with failure of prior medications, duration of disease, and standard deviation of diary pain scores at baseline were predictive of tanezumab responses as expressed by the WOMAC Pain scores at Week 16. Those who responded to tanezumab vs. placebo were identified based on the radiographic classification of the index joint and either age or smoking status. These secondary-data analyses identified distinct and common patient-based variables to predict response to placebo or tanezumab. These findings will inform the design of future clinical trials, helping to move forward clinical pharmacology and translational science.
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Affiliation(s)
- Luana Colloca
- Department of Pain and Translational Symptom Science, Placebo Beyond Opinions Center, School of Nursing, University of Maryland, Baltimore, Maryland, USA
| | | | - John T Farrar
- University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Bavbek S, Ozyigit LP, Baiardini I, Braido F, Roizen G, Jerschow E. Placebo, Nocebo, and Patient-Reported Outcome Measures in Drug Allergy. THE JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY. IN PRACTICE 2023; 11:371-379. [PMID: 36521832 DOI: 10.1016/j.jaip.2022.11.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 11/24/2022] [Accepted: 11/30/2022] [Indexed: 12/14/2022]
Affiliation(s)
- Sevim Bavbek
- Division of Allergy and Clinical of Immunology, Department of Chest Diseases, Ankara University, School of Medicine, Ankara, Turkey.
| | - Leyla Pur Ozyigit
- Adult Allergy Service, Glenfield Hospital, University Hospitals of Leicester NHS Trust, Leicester, United Kingdom
| | - Ilaria Baiardini
- Istituti di Ricovero e Cura a Carattere Scientifico, Ospedale Policlinico San Martino, Genova, Italy; Università di Genova, (DIMI), Genova, Italy
| | - Fulvio Braido
- Istituti di Ricovero e Cura a Carattere Scientifico, Ospedale Policlinico San Martino, Genova, Italy; Università di Genova, (DIMI), Genova, Italy
| | - Gigia Roizen
- Department of Immunology, Clinica Alemana De Santiago, Santiago, Chile
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Bosman M, Smeets F, Elsenbruch S, Tack J, Simrén M, Talley N, Winkens B, Masclee A, Keszthelyi D. Placebo response in pharmacological trials in patients with functional dyspepsia-A systematic review and meta-analysis. Neurogastroenterol Motil 2023; 35:e14474. [PMID: 36168188 PMCID: PMC10078497 DOI: 10.1111/nmo.14474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 07/18/2022] [Accepted: 09/12/2022] [Indexed: 02/02/2023]
Abstract
BACKGROUND Pharmacological trials in functional dyspepsia (FD) are associated with high placebo response rates. We aimed to identify the magnitude and contributing factors to the placebo response. METHODS We conducted a systematic review and meta-analysis including randomized controlled trials (RCTs) with a dichotomous outcome in adult patients with FD that compared an active pharmacotherapeutic treatment with placebo. Our main outcome was identification of the magnitude of the pooled placebo response rate for the following endpoints: symptom responder, symptom-free responder, adequate relief responder, and combined endpoint responder (i.e., the primary endpoint of each specific trial regarding treatment response). Several putative moderators (i.e., patient, disease, and trial characteristics) were examined. KEY RESULTS We included 26 RCTs in our analysis. The pooled placebo response rate was 39.6% (95% CI 30.1-50.0) using the symptom responder definition, 20.5% (12.8-31.0) using the symptom-free responder definition, 38.5% (33.8-43.6) using the adequate relief responder definition, and 35.5% (31.6-39.7) using the combined endpoint responder definition. A lower overall baseline symptom score was significantly associated with a higher placebo response rate. No other moderators were found to significantly impact the placebo response rate. Due to the lack of data, no analyses could be performed according to individual FD subtypes or symptoms. CONCLUSIONS AND INFERENCES The pooled placebo response rate in pharmacological trials in FD is about 39%, depending on which responder definitions is used. Future trials should consider applying an entry criterion based on minimal level of symptom severity to decrease the placebo response. We also suggest separate reporting of core FD symptoms pending more concrete harmonization efforts in FD trials.
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Affiliation(s)
- Michelle Bosman
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Center, Maastricht, The Netherlands
| | - Fabiënne Smeets
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Center, Maastricht, The Netherlands
| | - Sigrid Elsenbruch
- Department of Medical Psychology and Medical Sociology, Faculty of Medicine, Ruhr University Bochum, Bochum, Germany.,Department of Neurology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Jan Tack
- Translational Research Center for Gastrointestinal Disorders (TARGID), Catholic University of Leuven, Leuven, Belgium.,Division of Gastroenterology and Hepatology, University Hospitals Leuven, Leuven, Belgium
| | - Magnus Simrén
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Centre for Functional GI and Motility Disorders, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Nicholas Talley
- NHMRC Center of research Excellence in Digestive Health, University of Newcastle, Newcastle, New South Wales, Australia
| | - Bjorn Winkens
- Department of Methodology and Statistics, Care and Public Health Research Institute, Faculty of Health, Medicine, and Life Sciences, Maastricht University, Maastricht, The Netherlands
| | - Ad Masclee
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Center, Maastricht, The Netherlands
| | - Daniel Keszthelyi
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Center, Maastricht, The Netherlands
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12
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Factors Associated With Placebo Treatment Response in Functional Dyspepsia Clinical Trials. Am J Gastroenterol 2022; 118:685-691. [PMID: 36729385 DOI: 10.14309/ajg.0000000000002097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 10/12/2022] [Indexed: 02/03/2023]
Abstract
INTRODUCTION Controlling for potential placebo effects is an important aspect of gaining an accurate estimate of how much the therapy alone changes patient symptoms or other end points. When the placebo effect is large, this can lead to only a small fraction of changes seen in the active therapy group being attributed to the therapy itself. This problem has been well studied in some disorders of brain-gut interaction but not in functional dyspepsia where placebo response rates of 40% and higher have been reported. Understanding risk factors for placebo response might lead to changes in trial design that could reduce the magnitude of the problem. This study sought to identify risk factors for the placebo effect in a functional dyspepsia clinical trial with a longer-term aim of suggesting trial design changes that might minimize the problem. METHODS A secondary analysis of the clinical trial data was undertaken using 2 arms deemed to involve placebo therapy. Potential predictors were drawn from a wide range of patient characteristics including psychological, clinical, and physiological features. RESULTS Predictors of a stronger placebo effect on the gastrointestinal symptom rating scale included higher functional dyspepsia symptom burden at baseline (b = -0.101), coexisting irritable bowel syndrome (b = -0.436), and higher scores on the Nepean Dyspepsia Index eat/drink domain (-0.005). Baseline symptom burden and coexisting irritable bowel syndrome were found to be independent placebo predictors, explaining 13% of the variance in change in gastrointestinal symptom rating scale. Anxiety, childhood sexual abuse, sleep amount, and frequent abdominal pain were also found to be predictors of change in individual symptom scores. DISCUSSION The findings of this study yield actionable insights into trial methodology that may help to reduce the magnitude of the placebo effect in future functional dyspepsia treatment trials.
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13
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Iwama Y, Takamoto K, Hibi D, Nishimaru H, Matsumoto J, Setogawa T, Nishijo H. Young female participants show blunted placebo effects associated with blunted responses to a cue predicting a safe stimulus in the right dorsolateral prefrontal cortex. Front Neurosci 2022; 16:1001177. [PMID: 36263366 PMCID: PMC9574021 DOI: 10.3389/fnins.2022.1001177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 09/20/2022] [Indexed: 11/17/2022] Open
Abstract
Discrimination of cues predicting non-nociceptive/nociceptive stimuli is essential for predicting whether a non-painful or painful stimulus will be administered and for eliciting placebo/nocebo (pain reduction/pain enhancement) effects. Dysfunction of the neural system involved in placebo effects has been implicated in the pathology of chronic pain, while female sex is one of the important risk factors for development of chronic pain in young adults. The dorsolateral prefrontal cortex (dl-PFC) is suggested to be involved in placebo effects and is sensitive to sex and age. In this study, to examine the neural mechanisms by which sex and age alter placebo and nocebo effects, we analyzed cerebral hemodynamic activities in the dl-PFC in different sex and age groups during a differential conditioning task. During the training session, two different sounds were followed by low- and high-intensity electrical shocks. In the following recording session, electrical shocks, the intensity of which was mismatched to the sounds, were occasionally administered to elicit placebo and nocebo effects. In young female participants, both placebo effects and hemodynamic responses to the conditioned sounds in the right dl-PFC were significantly lower than those in elderly female participants, while there were no age differences in male participants. The hemodynamic responses to the sound paired with the safe stimulus in the right dl-PFC were significantly correlated with placebo effects, except in the young female group. These results suggest that blunted placebo effects in the young female participants are ascribed to blunted responses to the sound associated with the safe stimulus in the right dl-PFC, and that sex- and age-related factors may alter the responsiveness of the right dl-PFC to associative cues predicting a safe stimulus.
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Affiliation(s)
- Yudai Iwama
- System Emotional Science, Faculty of Medicine, University of Toyama, Toyama, Japan
| | - Kouichi Takamoto
- Department of Sport and Health Sciences, Faculty of Human Sciences, University of East Asia, Shimonoseki, Japan
| | - Daisuke Hibi
- Department of Anesthesiology, Faculty of Medicine, University of Toyama, Toyama, Japan
| | - Hiroshi Nishimaru
- System Emotional Science, Faculty of Medicine, University of Toyama, Toyama, Japan
- Research Center for Idling Brain Science (RCIBS), University of Toyama, Toyama, Japan
| | - Jumpei Matsumoto
- System Emotional Science, Faculty of Medicine, University of Toyama, Toyama, Japan
- Research Center for Idling Brain Science (RCIBS), University of Toyama, Toyama, Japan
| | - Tsuyoshi Setogawa
- System Emotional Science, Faculty of Medicine, University of Toyama, Toyama, Japan
- Research Center for Idling Brain Science (RCIBS), University of Toyama, Toyama, Japan
| | - Hisao Nishijo
- System Emotional Science, Faculty of Medicine, University of Toyama, Toyama, Japan
- Research Center for Idling Brain Science (RCIBS), University of Toyama, Toyama, Japan
- *Correspondence: Hisao Nishijo,
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14
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Aksu S, Soyata AZ, Mursalova Z, Eskicioğlu G, Tükel R. Transcranial direct current stimulation does not improve clinical and neurophysiological outcomes in panic disorder: A randomized sham-controlled trial. Psychiatry Clin Neurosci 2022; 76:384-392. [PMID: 35587504 DOI: 10.1111/pcn.13378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 05/08/2022] [Accepted: 05/16/2022] [Indexed: 11/28/2022]
Abstract
AIM Emerging evidence suggests that transcranial direct current stimulation (tDCS) has anxiolytic effects and may enhance emotional processing of threat and reduce threat-related attentional bias. Panic disorder (PD) is considered to be a fear network disorder along with prefrontal activity alterations. We aim to assess the effect of tDCS on clinical and physiological parameters in PD for the first time. METHODS In this triple-blind randomized sham-controlled pilot study, 30 individuals with PD were allocated into active and sham groups to receive 10 sessions of tDCS targeting the dorsolateral prefrontal cortex bilaterally at 2 mA for 20-min duration over 2 weeks. The clinical severity, threat-related attentional bias, interoceptive accuracy, and emotional recognition were assessed before, immediately after, and 1 month after tDCS. RESULTS Active tDCS, in comparison to sham, did not elicit more favorable clinical and neuropsychological/physiological outcomes in PD. CONCLUSION The present study provides the first clinical and neurobehavioral results of prefrontal tDCS in PD and indicates that prefrontal tDCS was not superior to sham in PD.
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Affiliation(s)
- Serkan Aksu
- Department of Physiology, Faculty of Medicine, Muğla Sıtkı Koçman University, Muğla, Turkey.,Department of Physiology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | | | - Zhala Mursalova
- Department of Psychiatry, Istanbul University, Istanbul Faculty of Medicine, Istanbul, Turkey
| | - Gaye Eskicioğlu
- Department of Psychology, Istanbul University, Istanbul, Turkey
| | - Raşit Tükel
- Department of Psychiatry, Istanbul University, Istanbul Faculty of Medicine, Istanbul, Turkey
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15
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Ziv G, Lidor R, Levin O. Reaction time and working memory in middle-aged gamers and non-gamers. Acta Psychol (Amst) 2022; 228:103666. [PMID: 35820337 DOI: 10.1016/j.actpsy.2022.103666] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 06/26/2022] [Accepted: 07/01/2022] [Indexed: 11/28/2022] Open
Abstract
The purpose of this study was to explore whether asking middle-aged gamers and non-gamers about their video games habits will affect their performance of cognitive-motor tasks. One-hundred and twenty-one participants were randomly assigned to four groups: (a) gamers who were asked about their playing habits prior to the study, (b) gamers who were asked about their playing habits following the study, (c) non-gamers who were asked about their playing habits prior to the study, and (d) non-gamers who were asked about their playing habits following the study. The participants performed three reaction time (RT) tasks and a digit-span memory task. In a task-switching task, gamers had more correct responses when they answered the questionnaire before performing the task compared with after the task. For the non-gamers, the opposite occurred. We conclude that some performance measures of cognitive-motor tasks could have been affected by the timing of the completion of the questionnaire. This finding should be known to researchers as it may lead to biases gaming research.
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Affiliation(s)
- Gal Ziv
- Motor Behavior Laboratory, The Academic College at Wingate, Netanya, Israel.
| | - Ronnie Lidor
- Motor Behavior Laboratory, The Academic College at Wingate, Netanya, Israel
| | - Oron Levin
- Movement Control & Neuroplasticity Research Group, KU Leuven, Leuven, Belgium; Department of Health Promotion and Rehabilitation, Lithuanian Sports University, Kaunas, Lithuania
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16
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Haile A, Watts M, Aichner S, Stahlberg F, Hoffmann V, Tschoep MH, Meissner K. Central correlates of placebo effects in nausea differ between men and women. Brain Behav 2022; 12:e2685. [PMID: 35810479 PMCID: PMC9392536 DOI: 10.1002/brb3.2685] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 04/29/2022] [Accepted: 06/12/2022] [Indexed: 11/22/2022] Open
Abstract
INTRODUCTION Despite growing evidence validating placebo effects in nausea, little is known about the underlying cortical mechanisms in women and men. Therefore, the present study examined sex differences and electroencephalography (EEG) characteristics of the placebo effect on nausea. METHODS On 2 consecutive days, 90 healthy subjects (45 females) were exposed to a nauseating visual stimulus. Nausea was continuously rated on an 11-point numeric rating scale, and 32 EEG channels were recorded. On day 2, subjects were randomly allocated to either placebo treatment or no treatment: the placebo group received sham acupuncture, whereas the control group did not receive any intervention. RESULTS In contrast to the control group, both sexes in the placebo group showed reduced signs for anticipatory nausea in the EEG, indexed by increased frontal lobe and anterior cingulate activity. Among women, the improvement in perceived nausea in the placebo group was accompanied by decreased activation in the parietal, frontal, and temporal lobes. In contrast, the placebo-related improvement of perceived nausea in men was accompanied by increased activation in the limbic and sublobar (insular) lobes. CONCLUSION Activation of the parietal lobe in women during the placebo intervention may reflect altered afferent activity from gastric mechanoreceptors during nausea-induced tachyarrhythmia, whereas in men, altered interoceptive signals in the insular cortex might play a role. Thus, the results suggest different cerebral mechanisms underlying the placebo effects in men and women, which could have implications for the treatment of nausea.
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Affiliation(s)
- Anja Haile
- Institute of Medical Psychology, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Mallissa Watts
- Institute of Medical Psychology, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Simone Aichner
- Institute of Medical Psychology, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Franziska Stahlberg
- Institute of Medical Psychology, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Verena Hoffmann
- Institute of Medical Psychology, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Matthias H Tschoep
- Helmholtz Diabetes Center and German Center for Diabetes Research, Helmholtz Zentrum München, Neuherberg, Germany.,Division of Metabolic Diseases, Department of Medicine, Technical University of Munich, Munich, Germany
| | - Karin Meissner
- Institute of Medical Psychology, Faculty of Medicine, LMU Munich, Munich, Germany.,Division of Health Promotion, Coburg University of Applied Sciences & Arts, Coburg, Germany
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17
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The neglect of sex: A call to action for including sex as a biological variable in placebo and nocebo research. Contemp Clin Trials 2022; 116:106734. [PMID: 35306216 PMCID: PMC9332926 DOI: 10.1016/j.cct.2022.106734] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Revised: 03/08/2022] [Accepted: 03/14/2022] [Indexed: 11/22/2022]
Abstract
Sex differences exist in the prevalence, progression and treatment efficacy of a wide array of medical conditions. While the placebo and nocebo effects have become increasingly relevant in the clinical arena, little is known about the influence of biological sex on placebo and nocebo effects. This paper discusses the existing, relatively limited and sometimes conflicting evidence about how sex impacts the occurrence and magnitude of the placebo and nocebo effects, mainly focusing on pain studies. We present recent evidence that when compared to men, women suffering from chronic orofacial pain may derive greater benefit from the placebo effect for analgesia. Nonetheless, we broadly argue that the field is not currently positioned to draw definitive conclusions and propose several important factors that may explain the inconsistency in the literature and that should be taken into account in future research. These include the specific target symptom of the placebo or nocebo manipulation and whether or not the target is related to the medical condition, the placebo or nocebo induction method, the sex of the experimenter or physician, and so forth. Future research should intentionally include sex a biological variable to favor translation of placebo and nocebo mechanisms into clinical applications.
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18
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Abstract
A placebo is an inert substance normally used in clinical trials for comparison with an active substance. However, a placebo has been shown to have an effect on its own; commonly known as the placebo effect. A placebo is an essential component in the design of conclusive clinical trials but has itself become the focus of intense research. The placebo effect is partly the result of positive expectations of the recipient on the state of health. Conversely, a nocebo effect is when negative expectations from a substance lead to poor treatment outcomes and/or adverse events. Randomized controlled trials in functional urology have demonstrated the importance of the placebo and nocebo effects across different diseases such as overactive bladder, urinary incontinence, lower urinary tract symptoms and interstitial cystitis/painful bladder syndrome, as well as male and female sexual dysfunction. Understanding the true nature of the placebo-nocebo complex and the scope of its effect in functional urology could help urologists to maximize the positive effects of this phenomenon while minimizing its potentially negative effects.
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19
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Wahba G, Neshkova E, Jutras G, Liu Chen Kiow J, Clément M, Willems P, Eouani BD, Courbette O, Ayuso É, Bouin M. Lidocaine before esophageal manometry and ambulatory pH monitoring: A randomized controlled trial. Neurogastroenterol Motil 2021; 33:e14167. [PMID: 33969923 DOI: 10.1111/nmo.14167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 04/03/2021] [Accepted: 04/15/2021] [Indexed: 02/08/2023]
Abstract
BACKGROUND Lidocaine is commonly applied to improve the tolerance of esophageal manometry (EM) and ambulatory pH monitoring (PM). We recently published data suggesting a benefit to this practice and we aimed to confirm these findings in a randomized trial. METHODS We conducted a double-blind, randomized trial of lidocaine nasal spray versus placebo (saline) before EM and PM. Patients referred to our center who met inclusion criteria were enrolled. Patients were asked to fill a questionnaire after their test and patient-reported adverse effects were compared. KEY RESULTS Three hundred and four patients were enrolled in our trial. Lidocaine and placebo groups were demographically similar. The primary outcome, pain during catheter insertion, occurred in 60/148 (40.5%) patients in the lidocaine group versus in 72/152 (47.4%) patients in the placebo group (OR: 0.76 [95% CI: 0.48-1.20]; p = 0.23). Patients receiving lidocaine were less likely to report nausea during test recording (OR: 0.48 [95% CI: 0.24-0.91]; p = 0.02) and reported slightly lower intensity of pain during both catheter insertion and test recording (4.68 ± 2.06 versus 5.41 ± 2.24 on 10; p = 0.048 and 3.71 ± 2.00 versus 4.93 ± 2.55 on 10; p = 0.03, respectively). Furthermore, patients receiving lidocaine were less likely to report their test as globally uncomfortable and painful (57% vs. 75%; p = 0.003 and 14% vs. 21%; p = 0.02, respectively). No events of systemic lidocaine toxicity occurred during the study period. CONCLUSIONS Routine use of lidocaine before esophageal function tests does not reduce pain during catheter insertion but may provide other modest benefits with limited toxicity.
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Affiliation(s)
- George Wahba
- Centre hospitalier de l'Université de Montréal (CHUM), Montréal, Québec, Canada
| | - Elissaveta Neshkova
- Centre hospitalier de l'Université de Montréal (CHUM), Montréal, Québec, Canada
| | - Gabrielle Jutras
- Centre hospitalier de l'Université de Montréal (CHUM), Montréal, Québec, Canada
| | | | - Marianne Clément
- Centre hospitalier de l'Université de Montréal (CHUM), Montréal, Québec, Canada
| | - Philippe Willems
- Centre hospitalier de l'Université de Montréal (CHUM), Montréal, Québec, Canada
| | - Benny-Darold Eouani
- Centre hospitalier de l'Université de Montréal (CHUM), Montréal, Québec, Canada
| | - Olivier Courbette
- Centre hospitalier de l'Université de Montréal (CHUM), Montréal, Québec, Canada
| | - Éloïse Ayuso
- Centre hospitalier de l'Université de Montréal (CHUM), Montréal, Québec, Canada
| | - Mickael Bouin
- Centre hospitalier de l'Université de Montréal (CHUM), Montréal, Québec, Canada
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20
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Bosman M, Elsenbruch S, Corsetti M, Tack J, Simrén M, Winkens B, Boumans T, Masclee A, Keszthelyi D. The placebo response rate in pharmacological trials in patients with irritable bowel syndrome: a systematic review and meta-analysis. Lancet Gastroenterol Hepatol 2021; 6:459-473. [PMID: 33765447 DOI: 10.1016/s2468-1253(21)00023-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 01/12/2021] [Accepted: 01/14/2021] [Indexed: 12/14/2022]
Abstract
BACKGROUND Clinical trials in irritable bowel syndrome are associated with high placebo response rates. We aimed to identify the magnitude of the placebo response and the contributing factors to this occurrence. METHODS We did a systematic review and meta-analysis with a search of MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials between April 1, 1959, and April 30, 2020. We included all randomised controlled trials that compared an active pharmacotherapeutic agent with placebo and had a dichotomous outcome of response to therapy (in terms of global improvement or improvement in abdominal pain) in adults (aged ≥18 years) with irritable bowel syndrome. Exclusion criteria were trials reporting on treatment satisfaction as a dichotomous outcome of response to therapy or clinician-reported outcomes and a treatment duration of less than 4 weeks. Our main outcome was identification of the magnitude of the pooled placebo response rate for the following endpoints: global improvement, abdominal pain, and US Food and Drug Administration (FDA) endpoints. We extracted information from published reports and pooled proportions through meta-analysis with random effects. The study was registered with PROSPERO, CRD42020170908. FINDINGS Of the 6863 publications identified, 70 articles describing 73 randomised controlled trials were included in our analysis. The pooled placebo response rate was 27·3% (95% CI 24·3-30·9) using the global improvement endpoint, 34·4% (31·2-37·8) using the abdominal pain endpoint, and 17·9% (15·2-21·0) using the composite FDA endpoint responder definition, all with substantial heterogeneity between the trials. Studies published before 2006, and those done in Europe, with a parallel design, a run-in period of 2 weeks or less, a dose schedule of three times a day or more, or a smaller sample size of the control group were significantly associated with an increased pooled placebo response rate. INTERPRETATION More than a quarter of patients with irritable bowel syndrome had a placebo response in terms of global improvement, with multiple associated moderators. We recommend future trials apply a run-in period of at least 2 weeks and dose once or twice a day to minimise the placebo response rate. FUNDING None.
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Affiliation(s)
- Michelle Bosman
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, Netherlands.
| | - Sigrid Elsenbruch
- Department of Medical Psychology and Medical Sociology, Faculty of Medicine, Ruhr University Bochum, Bochum, Germany; Department of Neurology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Maura Corsetti
- NIHR Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust, Nottingham, UK; University of Nottingham and Nottingham Digestive Diseases Centre, School of Medicine, University of Nottingham, Nottingham, UK
| | - Jan Tack
- Translational Research Center for Gastrointestinal Disorders, Catholic University of Leuven, Leuven, Belgium; Division of Gastroenterology and Hepatology, University Hospitals Leuven, Leuven, Belgium
| | - Magnus Simrén
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; Centre for Functional GI and Motility Disorders, University of North Carolina, Chapel Hill, NC, USA
| | - Bjorn Winkens
- Department of Methodology and Statistics, Care and Public Health Research Institute, Faculty of Health, Medicine, and Life Sciences, Maastricht University, Maastricht, Netherlands
| | - Thimo Boumans
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, Netherlands
| | - Ad Masclee
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, Netherlands
| | - Daniel Keszthelyi
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, Netherlands
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21
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Enck P, Klosterhalfen S. The Placebo and Nocebo Responses in Clinical Trials in Inflammatory Bowel Diseases. Front Pharmacol 2021; 12:641436. [PMID: 33867990 PMCID: PMC8044413 DOI: 10.3389/fphar.2021.641436] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 01/28/2021] [Indexed: 12/12/2022] Open
Abstract
Placebo and nocebo responses are mostly discussed in clinical trials with functional bowel disorders. Much less has been investigated and is known in gastrointestinal diseases beyond irritable bowel syndrome (IBS), especially in inflammatory bowel diseases (IBD). For the purpose of this review, we screened the Journal of Interdisciplinary Placebo Studies (JIPS) database with approximately 4,500 genuine placebo research articles and identified nine meta-analyses covering more than 135 randomized and placebo-controlled trials (RCTs) with more than 10,000 patients with Crohn´s disease (CD) and another five meta-analyses with 150 RCTs and more than 10,000 patients with ulcerative colitis (UC). Only three discussed nocebo effects, especially in the context of clinical use of biosimilars to treat inflammation. The articles were critically analyzed with respect to the size of the placebo response in CD and UC, its effects on clinical improvement versus maintenance of remission, and mediators and moderators of the response identified. Finally, we discussed and compared the differences and similarities of the placebo responses in IBD and IBS and the nocebo effect in switching from biologics to biosimilars in IBD management.
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Affiliation(s)
- Paul Enck
- Department of Internal Medicine VI: Psychosomatic Medicine and Psychotherapy, University Hospital Tübingen, Tübingen, Germany
| | - Sibylle Klosterhalfen
- Department of Internal Medicine VI: Psychosomatic Medicine and Psychotherapy, University Hospital Tübingen, Tübingen, Germany
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22
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Smits RM, Veldhuijzen DS, Olde Hartman T, Peerdeman KJ, Van Vliet LM, Van Middendorp H, Rippe RCA, Wulffraat NM, Evers AWM. Explaining placebo effects in an online survey study: Does 'Pavlov' ring a bell? PLoS One 2021; 16:e0247103. [PMID: 33705397 PMCID: PMC7951811 DOI: 10.1371/journal.pone.0247103] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 02/01/2021] [Indexed: 12/12/2022] Open
Abstract
OBJECTIVES Despite the increasing knowledge about placebo effects and their beneficial impact on treatment outcomes, strategies that explicitly employ these mechanisms remain scarce. To benefit from placebo effects, it is important to gain better understanding in how individuals want to be informed about placebo effects (for example about the underlying mechanisms that steer placebo effects). The main aim of this study was to investigate placebo information strategies in a general population sample by assessing current placebo knowledge, preferences for different placebo explanations (built around well-known mechanisms involved in placebo effects), and attitudes and acceptability towards the use of placebo effects in treatment. DESIGN Online survey. SETTING Leiden, The Netherlands. PARTICIPANTS 444 participants (377 completers), aged 16-78 years. MAIN OUTCOME MEASURES Current placebo knowledge, placebo explanation preferences, and placebo attitudes and acceptability. RESULTS Participants scored high on current placebo knowledge (correct answers: M = 81.15%, SD = 12.75). Comparisons of 8 different placebo explanations revealed that participants preferred explanations based on brain mechanisms and positive expectations more than all other explanations (F(7, 368) = 3.618, p = .001). Furthermore, attitudes and acceptability for placebos in treatment varied for the type of the condition (i.e. more acceptant for psychological complaints) and participants indicated that physicians do not always have to be honest while making use of placebo effects for therapeutic benefit. CONCLUSION Our results brought forth new evidence in placebo information strategies, and indicated that explanations based on brain mechanisms and positive expectations were most preferred. These results can be insightful to construct placebo information strategies for both clinical context and research practices.
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Affiliation(s)
- Rosanne M. Smits
- Health, Medical and Neuropsychology unit, Leiden University, Leiden, The Netherlands
- Leiden Institute for Brain and Cognition, Leiden, The Netherlands
- Pediatric Immunology and Rheumatology, Wilhelmina Children’s Hospital, Utrecht, The Netherlands
| | - Dieuwke S. Veldhuijzen
- Health, Medical and Neuropsychology unit, Leiden University, Leiden, The Netherlands
- Leiden Institute for Brain and Cognition, Leiden, The Netherlands
- Pediatric Immunology and Rheumatology, Wilhelmina Children’s Hospital, Utrecht, The Netherlands
| | - Tim Olde Hartman
- Department of Primary and Community Care, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Kaya J. Peerdeman
- Health, Medical and Neuropsychology unit, Leiden University, Leiden, The Netherlands
- Leiden Institute for Brain and Cognition, Leiden, The Netherlands
| | - Liesbeth M. Van Vliet
- Health, Medical and Neuropsychology unit, Leiden University, Leiden, The Netherlands
- Leiden Institute for Brain and Cognition, Leiden, The Netherlands
| | - Henriët Van Middendorp
- Health, Medical and Neuropsychology unit, Leiden University, Leiden, The Netherlands
- Leiden Institute for Brain and Cognition, Leiden, The Netherlands
| | - Ralph C. A. Rippe
- Research Methods and Statistics, Institute of Education and Child Studies, Leiden University, Leiden, The Netherlands
| | - Nico M. Wulffraat
- Pediatric Immunology and Rheumatology, Wilhelmina Children’s Hospital, Utrecht, The Netherlands
| | - Andrea W. M. Evers
- Health, Medical and Neuropsychology unit, Leiden University, Leiden, The Netherlands
- Leiden Institute for Brain and Cognition, Leiden, The Netherlands
- Department of Psychiatry, Leiden University Medical Center, Leiden, The Netherlands
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23
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Placebo Response in Patients with Oral Therapy for Overactive Bladder: A Systematic Review and Meta-analysis. Eur Urol Focus 2021; 8:239-252. [PMID: 33674256 DOI: 10.1016/j.euf.2021.02.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 01/10/2021] [Accepted: 02/05/2021] [Indexed: 12/28/2022]
Abstract
CONTEXT The role of a placebo response in the management of overactive bladder (OAB) remains unclear. OBJECTIVE The aim of this review is to methodically study the placebo response extracted from the control arms of randomized clinical trials assessing therapy in patients with OAB. EVIDENCE ACQUISITION Medline (PubMed), The Cochrane Library, EMBASE, and Scopus were searched to identify randomized controlled trials (RCTs) published until September 2019. Randomized placebo-controlled trials investigating oral drug therapy for OAB were included. The articles were critically appraised by two reviewers. The primary outcomes were the placebo response in the main patient-reported urinary outcomes together with assessing the impact of patient demographic factors on the placebo response. EVIDENCE SYNTHESIS The initial search resulted in 1982 records after reviewing the titles and abstracts, and reference lists of other systematic reviews; 57 studies with an overall estimated 12 901 patients were included in the meta-analysis. The included studies were of overall high/acceptable quality. The standardized mean difference was -0.45 (95% confidence interval [CI] -0.51 to -0.40; p<0.001) for daily micturition episodes, -0.33 (95% CI -0.42 to -0.24; p<0.001) for daily nocturia episodes, -0.46 (95% CI -0.55 to -0.37; p<0.001) for urgency urinary incontinence episodes, -0.50 (95% CI -0.61 to -0.39; p<0.001) for daily urgency episodes, -0.51 (95% CI -0.60 to -0.43; p<0.001) for daily incontinence episodes, and 0.25 (95% CI 0.211-0.290; p<0.001) for volume voided per micturition. The meta-regression of age-related impact of the placebo response on nocturia showed a slope of -0.02 (p<0.001). CONCLUSIONS Placebo has a statistically significant effect on improving symptoms and signs associated with OAB; this effect is age dependent. However, there is no consensus on what change of OAB symptoms and signs is clinically meaningful for the affected patient. Taken together, the placebo response seems to be non-negligible in OAB, supporting the need for placebo control in RCTs. PATIENT SUMMARY Placebo is an inert treatment method often used in clinical research for comparison with active treatment. However, studies show that placebo has an effect of its own. A placebo response means the total improvement resulting from receiving a placebo. In our study, placebo had a significant role in improving the symptoms of overactive bladder.
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24
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Olson EM, Akintola T, Phillipsc J, Blasini M, Haycock NR, Martinez PE, Greenspan JD, Dorsey SG, Wang Y, Colloca L. Effects of sex on placebo effects in chronic pain participants: a cross-sectional study. Pain 2021; 162:531-542. [PMID: 32826757 PMCID: PMC7854995 DOI: 10.1097/j.pain.0000000000002038] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Accepted: 08/03/2020] [Indexed: 12/19/2022]
Abstract
ABSTRACT Sex-related differences can influence outcomes of randomized clinical trials and may jeopardize the effectiveness of pain management and other therapeutics. Thus, it is essential to understand the mechanistic and translational aspects of sex differences in placebo outcomes. Recently, studies in healthy participants have shed light on how sex-related placebo effects might influence outcomes, yet no research has been conducted in a patient population. Herein, we used a tripartite approach to evaluate the interaction of prior therapeutic experience (eg, conditioning), expectations, and placebo effects in 280 chronic (orofacial) pain patients (215 women). In this cross-sectional study, we assessed sex differences in placebo effects, conditioning as a proxy of prior therapeutic effects, and expectations evaluated before and after the exposure to positive outcomes, taking into account participant-experimenter sex concordance and hormonal levels (estradiol and progesterone assessed in premenopausal women). We used mediation analysis to determine how conditioning strength and expectations impacted sex differences in placebo outcomes. Independent of gonadal hormone levels, women showed stronger placebo effects than men. We also found significant statistical sex differences in the conditioning strength and reinforced expectations whereby reinforced expectations mediated the sex-related placebo effects. In addition, the participant-experimenter sex concordance influenced conditioning strength, reinforced expectations, and placebo effects in women but not in men. Our findings suggest that women experience larger conditioning effects, expectations, and placebo effects emphasizing the need to consider sex as a biological variable when placebo components of any outcomes are part of drug development trials and in pain management.
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Affiliation(s)
| | - Titilola Akintola
- Department of Pain and Translational Symptom Science, School of Nursing, University of Maryland, Baltimore, MD, USA
| | - Jane Phillipsc
- Department of Neural and Pain Sciences, and Brotman Facial Pain Clinic, School of Dentistry, University of Maryland, Baltimore, MD, USA
| | - Maxie Blasini
- Department of Pain and Translational Symptom Science, School of Nursing, University of Maryland, Baltimore, MD, USA
| | - Nathaniel R. Haycock
- Department of Pain and Translational Symptom Science, School of Nursing, University of Maryland, Baltimore, MD, USA
| | - Pedro E. Martinez
- National Institutes of Health, National Institute of Mental Health, Bethesda, MD, USA
| | - Joel D. Greenspan
- Department of Neural and Pain Sciences, and Brotman Facial Pain Clinic, School of Dentistry, University of Maryland, Baltimore, MD, USA
- University of Maryland Center to Advance Chronic Pain Research, Baltimore, MD, USA
| | - Susan G. Dorsey
- Department of Pain and Translational Symptom Science, School of Nursing, University of Maryland, Baltimore, MD, USA
- University of Maryland Center to Advance Chronic Pain Research, Baltimore, MD, USA
| | - Yang Wang
- Department of Pain and Translational Symptom Science, School of Nursing, University of Maryland, Baltimore, MD, USA
| | - Luana Colloca
- Department of Pain and Translational Symptom Science, School of Nursing, University of Maryland, Baltimore, MD, USA
- University of Maryland Center to Advance Chronic Pain Research, Baltimore, MD, USA
- Department of Anesthesiology, School of Medicine, University of Maryland, Baltimore, MD, USA
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25
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Özdemir V, Endrenyi L. Rethinking Clinical Trials and Personalized Medicine with Placebogenomics and Placebo Dose. OMICS-A JOURNAL OF INTEGRATIVE BIOLOGY 2020; 25:1-12. [PMID: 33305994 DOI: 10.1089/omi.2020.0208] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Pharmacogenomics, nutrigenomics, vaccinomics, and the nascent field of plant omics are examples of variability science. They are embedded within an overarching framework of personalized medicine. Across these public health specialties, the significance and biology of the placebo response have been historically neglected. A placebo is any substance such as a sugar pill administered in the guise of medication, but one that does not have pharmacological activity. Placebos do have clinical effects, however, that can be substantive in magnitude and vary markedly from person-to-person depending, for example, on the type of disease, symptoms, or clinical trial design. Research over the past several decades attests to a genuine neurobiological basis for placebo effects. All drugs have placebo components that contribute to their overall treatment effect. Placebos are used in clinical trials as control groups to ascertain the net pharmacological effect of a drug candidate. Not only less well known but also relevant to rational therapeutics and personalized medicine is the nocebo. A nocebo effect occurs when an inert substance is administered in a context that induces negative expectations, worsening patients' symptoms. With the COVID-19 pandemic, there are high public expectations for new vaccines and medicines to end the contagion, while at the same time antiscience, post-truth, and antivaccine movements are worrisomely on the rise. These social movements, changes in public health cultures, and conditioned behavioral responses can trigger both placebo and nocebo effects. Hence, in clinical trials, forecasting and explaining placebo and nocebo variability are more important than ever for robust science and personalized health care. Against this overarching context, this article provides (1) a brief history of placebo and (2) a discussion on biology, mechanisms, and variability of placebo effects, and (3) discusses three emerging new concepts: placebogenomics, nocebogenomics, and augmented placebo, that is, the notion of a "placebo dose." We conclude with a roadmap for placebogenomics, its synergies with the nascent field of social pharmacology, and the ways in which a new taxonomy of drug and placebo variability can be anticipated in the next decade.
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Affiliation(s)
- Vural Özdemir
- OMICS: A Journal of Integrative Biology, New Rochelle, New York, USA
| | - Laszlo Endrenyi
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, Canada
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26
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Lin C, Cai X, Yang W, Lv F, Nie L, Ji L. Age, sex, disease severity, and disease duration difference in placebo response: implications from a meta-analysis of diabetes mellitus. BMC Med 2020; 18:322. [PMID: 33190640 PMCID: PMC7667845 DOI: 10.1186/s12916-020-01787-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 09/17/2020] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND The placebo response in patients with diabetes mellitus is very common. A systematic evaluation needs to be updated with the current evidence about the placebo response in diabetes mellitus and the associated factors in clinical trials of anti-diabetic medicine. METHODS Literature research was conducted in Medline, Embase, the Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov for studies published between the date of inception and June 2019. Randomized placebo-controlled trials conducted in type 1and type 2 diabetes mellitus (T1DM/T2DM) were included. Random-effects model and meta-regression analysis were accordingly used. This meta-analysis was registered in PROSPERO as CRD42014009373. RESULTS Significantly weight elevation (effect size (ES) = 0.33 kg, 95% CI, 0.03 to 0.61 kg) was observed in patients with placebo treatments in T1DM subgroup while significantly HbA1c reduction (ES = - 0.12%, 95% CI, - 0.16 to - 0.07%) and weight reduction (ES = - 0.40 kg, 95% CI, - 0.50 to - 0.29 kg) were observed in patients with placebo treatments in T2DM subgroup. Greater HbA1c reduction was observed in patients with injectable placebo treatments (ES = - 0.22%, 95% CI, - 0.32 to - 0.11%) versus oral types (ES = - 0.09%, 95% CI, - 0.14 to - 0.04%) in T2DM (P = 0.03). Older age (β = - 0.01, 95% CI, - 0.02 to - 0.01, P < 0.01) and longer diabetes duration (β = - 0.02, 95% CI, - 0.03 to - 0.21 × 10-2, P = 0.03) was significantly associated with more HbA1c reduction by placebo in T1DM. However, younger age (β = 0.02, 95% CI, 0.01 to 0.03, P = 0.01), lower male percentage (β = 0.01, 95% CI, 0.22 × 10-2, 0.01, P < 0.01), higher baseline BMI (β = - 0.02, 95% CI, - 0.04 to - 0.26 × 10-2, P = 0.02), and higher baseline HbA1c (β = - 0.09, 95% CI, - 0.16 to - 0.01, P = 0.02) were significantly associated with more HbA1c reduction by placebo in T2DM. Shorter diabetes duration (β = 0.06, 95% CI, 0.06 to 0.10, P < 0.01) was significantly associated with more weight reduction by placebo in T2DM. However, the associations between baseline BMI, baseline HbA1c, and placebo response were insignificant after the adjusted analyses. CONCLUSION The placebo response in diabetes mellitus was systematically outlined. Age, sex, disease severity (indirectly reflected by baseline BMI and baseline HbA1c), and disease duration were associated with placebo response in diabetes mellitus. The association between baseline BMI, baseline HbA1c, and placebo response may be the result of regression to the mean.
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Affiliation(s)
- Chu Lin
- Department of Endocrinology and Metabolism, Peking University People's Hospital, No.11 Xizhimen South Street, Xicheng District, Beijing, 100044, China
| | - Xiaoling Cai
- Department of Endocrinology and Metabolism, Peking University People's Hospital, No.11 Xizhimen South Street, Xicheng District, Beijing, 100044, China.
| | - Wenjia Yang
- Department of Endocrinology and Metabolism, Peking University People's Hospital, No.11 Xizhimen South Street, Xicheng District, Beijing, 100044, China
| | - Fang Lv
- Department of Endocrinology and Metabolism, Peking University People's Hospital, No.11 Xizhimen South Street, Xicheng District, Beijing, 100044, China
| | - Lin Nie
- Department of Endocrinology and Metabolism, Beijing Airport Hospital, Beijing, China
| | - Linong Ji
- Department of Endocrinology and Metabolism, Peking University People's Hospital, No.11 Xizhimen South Street, Xicheng District, Beijing, 100044, China.
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27
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Hall KT, Vase L, Tobias DK, Dashti HT, Vollert J, Kaptchuk TJ, Cook NR. Historical Controls in Randomized Clinical Trials: Opportunities and Challenges. Clin Pharmacol Ther 2020; 109:343-351. [PMID: 32602555 DOI: 10.1002/cpt.1970] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 06/11/2020] [Indexed: 12/19/2022]
Abstract
Randomized control trials (RCTs) with placebo are the gold standard for determining efficacy of novel pharmaceutical treatments. Since their inception, over 75 years ago, researchers have amassed a large body of underutilized data on outcomes in the placebo control arms of these trials. Although rare disease indications have used these historical placebo data as synthetic controls to reduce burden on patients and accelerate drug discovery, broad use of historical controls is in its infancy. Large-scale historical placebo data could be leveraged to benefit both drug developers and patients if warehoused and made more available to guide trial design and analysis. Here, we examine challenges in utilizing historical controls related to heterogeneity in trial design, outcome ascertainment, patient characteristics, and unmeasured pharmacogenomic effects. We then discuss the advantages and disadvantages of current approaches and propose a path forward to broader use of historical controls in RCTs.
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Affiliation(s)
- Kathryn T Hall
- Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA
| | - Lene Vase
- Department of Psychology and Behavioral Sciences, School of Business and Social Sciences, Aarhus University, Aarhus, Denmark
| | - Deirdre K Tobias
- Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA
| | - Hesam T Dashti
- Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA
| | - Jan Vollert
- Pain Research, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, London, UK.,Neurophysiology, Centre for Biomedicine and Medical Technology Mannheim, Medical Faculty Mannheim, Ruprecht-Karls-University, Heidelberg, Germany
| | - Ted J Kaptchuk
- Harvard Medical School, Boston, Massachusetts, USA.,Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
| | - Nancy R Cook
- Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA
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28
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Oseltamivir for coronavirus illness: post-hoc exploratory analysis of an open-label, pragmatic, randomised controlled trial in European primary care from 2016 to 2018. Br J Gen Pract 2020; 70:e444-e449. [PMID: 32571773 PMCID: PMC7311109 DOI: 10.3399/bjgp20x711941] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 04/07/2020] [Indexed: 12/12/2022] Open
Abstract
Background Patients infected with the novel coronavirus (SARS-CoV-2) are being treated empirically with oseltamivir, but there is little evidence from randomised controlled trials to support the treatment of coronavirus infections with oseltamivir. Aim To determine whether adding oseltamivir to usual care reduces time to recovery in symptomatic patients who have tested positive for coronavirus (not including SARS-CoV-2). Design and setting Exploratory analysis of data from an open-label, pragmatic, randomised controlled trial during three influenza seasons, from 2016 to 2018, in primary care research networks, in 15 European countries. Method Patients aged ≥1 year presenting to primary care with influenza-like illness (ILI), and who tested positive for coronavirus (not including SARS-CoV-2), were randomised to usual care or usual care plus oseltamivir. The primary outcome was time to recovery defined as a return to usual activities, with minor or absent fever, headache, and muscle ache. Results Coronaviruses (CoV-229E, CoV-OC43, CoV-KU1 and CoV-NL63) were identified in 308 (9%) out of 3266 randomised participants in the trial; 153 of these were allocated to usual care and 155 to usual care plus oseltamivir; the primary outcome was ascertained in 136 and 147 participants, respectively. The median time to recovery was shorter in patients randomised to oseltamivir: 4 days (interquartile range [IQR] 3–6) versus 5 days (IQR 3–8; hazard ratio 1.31; 95% confidence interval = 1.03 to 1.66; P = 0.026). Conclusion Primary care patients with ILI testing positive for coronavirus (not including SARS-CoV-2) recovered sooner when oseltamivir was added to usual care compared with usual care alone. This may be of relevance to the primary care management of COVID-19.
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29
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Ben-Sheetrit J, Peskin M, Newcorn JH, Daniely Y, Shbiro L, Rotem A, Weizman A, Manor I. Characterizing the Placebo Response in Adults With ADHD. J Atten Disord 2020; 24:425-433. [PMID: 29926752 DOI: 10.1177/1087054718780328] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Objective: Several ADHD pharmacological trials reported high placebo response (PR) rates. This study aims to characterize the PR in adult ADHD. Method: A retrospective cohort analysis of the placebo arm (140 adults with ADHD, 18-55 yrs, M:F 46.4%-53.6%) of a 6-week randomized, multicenter, double-blind metadoxine study, using Conners' Adult ADHD Rating Scale (CAARS) and the Adult ADHD Self-Report Scale (ASRS), was conducted. Results: Pre-post changes in placebo-treated adults were significant for both the CAARS and ASRS, F(2.9, 404.5) = 61.2, p < .00001, F(2.8, 383.0) = 43.1, p < .00001, respectively. Less than half of the participants had a PR which began early in treatment and persisted; almost 50% had a variable, inconsistent PR. Conclusion: In the current sample, PR in adult ADHD was prominent on both symptom scales and the investigator-rater instrument. Therefore, using investigator ratings as a primary endpoint does not necessarily attenuate PR. Of note, about half of the PR is variable, suggesting unreliable determination of efficacy.
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Affiliation(s)
| | - Miriam Peskin
- Geha Mental Health Center, Petah Tikva, Israel.,Tel-Aviv University, Israel
| | | | | | - Liat Shbiro
- Geha Mental Health Center, Petah Tikva, Israel
| | - Ann Rotem
- Geha Mental Health Center, Petah Tikva, Israel
| | - Abraham Weizman
- Geha Mental Health Center, Petah Tikva, Israel.,Tel-Aviv University, Israel
| | - Iris Manor
- Geha Mental Health Center, Petah Tikva, Israel.,Tel-Aviv University, Israel
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30
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Butler CC, van der Velden AW, Bongard E, Saville BR, Holmes J, Coenen S, Cook J, Francis NA, Lewis RJ, Godycki-Cwirko M, Llor C, Chlabicz S, Lionis C, Seifert B, Sundvall PD, Colliers A, Aabenhus R, Bjerrum L, Jonassen Harbin N, Lindbæk M, Glinz D, Bucher HC, Kovács B, Radzeviciene Jurgute R, Touboul Lundgren P, Little P, Murphy AW, De Sutter A, Openshaw P, de Jong MD, Connor JT, Matheeussen V, Ieven M, Goossens H, Verheij TJ. Oseltamivir plus usual care versus usual care for influenza-like illness in primary care: an open-label, pragmatic, randomised controlled trial. Lancet 2020; 395:42-52. [PMID: 31839279 DOI: 10.1016/s0140-6736(19)32982-4] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 11/06/2019] [Accepted: 11/08/2019] [Indexed: 12/25/2022]
Abstract
BACKGROUND Antivirals are infrequently prescribed in European primary care for influenza-like illness, mostly because of perceived ineffectiveness in real world primary care and because individuals who will especially benefit have not been identified in independent trials. We aimed to determine whether adding antiviral treatment to usual primary care for patients with influenza-like illness reduces time to recovery overall and in key subgroups. METHODS We did an open-label, pragmatic, adaptive, randomised controlled trial of adding oseltamivir to usual care in patients aged 1 year and older presenting with influenza-like illness in primary care. The primary endpoint was time to recovery, defined as return to usual activities, with fever, headache, and muscle ache minor or absent. The trial was designed and powered to assess oseltamivir benefit overall and in 36 prespecified subgroups defined by age, comorbidity, previous symptom duration, and symptom severity, using a Bayesian piece-wise exponential primary analysis model. The trial is registered with the ISRCTN Registry, number ISRCTN 27908921. FINDINGS Between Jan 15, 2016, and April 12, 2018, we recruited 3266 participants in 15 European countries during three seasonal influenza seasons, allocated 1629 to usual care plus oseltamivir and 1637 to usual care, and ascertained the primary outcome in 1533 (94%) and 1526 (93%). 1590 (52%) of 3059 participants had PCR-confirmed influenza infection. Time to recovery was shorter in participants randomly assigned to oseltamivir (hazard ratio 1·29, 95% Bayesian credible interval [BCrI] 1·20-1·39) overall and in 30 of the 36 prespecified subgroups, with estimated hazard ratios ranging from 1·13 to 1·72. The estimated absolute mean benefit from oseltamivir was 1·02 days (95% [BCrI] 0·74-1·31) overall, and in the prespecified subgroups, ranged from 0·70 (95% BCrI 0·30-1·20) in patients younger than 12 years, with less severe symptoms, no comorbidities, and shorter previous illness duration to 3·20 (95% BCrI 1·00-5·50) in patients aged 65 years or older who had more severe illness, comorbidities, and longer previous illness duration. Regarding harms, an increased burden of vomiting or nausea was observed in the oseltamivir group. INTERPRETATION Primary care patients with influenza-like illness treated with oseltamivir recovered one day sooner on average than those managed by usual care alone. Older, sicker patients with comorbidities and longer previous symptom duration recovered 2-3 days sooner. FUNDING European Commission's Seventh Framework Programme.
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Affiliation(s)
| | - Alike W van der Velden
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, Netherlands
| | - Emily Bongard
- Department of Primary Care Health Services, University of Oxford, Oxford, UK
| | - Benjamin R Saville
- Berry Consultants, Austin, Texas; Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Jane Holmes
- Centre for Statistics in Medicine, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, UK
| | - Samuel Coenen
- Centre for General Practice, Department of Primary and Interdisciplinary Care, University of Antwerp, Antwerp, Belgium
| | - Johanna Cook
- Department of Primary Care Health Services, University of Oxford, Oxford, UK
| | - Nick A Francis
- Primary Care and Population Sciences, University of Southampton, Southampton, UK
| | - Roger J Lewis
- Harbor-UCLA Medical Center, Torrance, CA, USA; David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; Berry Consultants, Austin, TX, USA
| | - Maciek Godycki-Cwirko
- Centre for Family and Community Medicine, Faculty of Health Sciences, Medical University of Lodz, Lodz, Poland
| | - Carl Llor
- University Institute in Primary Care Research Jordi Gol, Via Roma Health Centre, Barcelona, Spain
| | - Sławomir Chlabicz
- Department of Family Medicine, Medical University of Bialystok, Bialystok, Poland
| | - Christos Lionis
- Clinic of Social and Family Medicine, Faculty of Medicine, University of Crete, Crete, Greece
| | - Bohumil Seifert
- Department of General Practice, First Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Pär-Daniel Sundvall
- Research and Development Primary Health Care-Region Västra Götaland, Institute of Medicine, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Annelies Colliers
- Centre for General Practice, Department of Primary and Interdisciplinary Care, University of Antwerp, Antwerp, Belgium
| | - Rune Aabenhus
- Section and Research Unit of General Practice, Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Lars Bjerrum
- Section and Research Unit of General Practice, Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Nicolay Jonassen Harbin
- Antibiotic Center for Primary Care, Department of General Practice, Institute of Health and Society, University of Oslo, Oslo, Norway
| | - Morten Lindbæk
- Antibiotic Center for Primary Care, Department of General Practice, Institute of Health and Society, University of Oslo, Oslo, Norway
| | - Dominik Glinz
- Basel Institute for Clinical Epidemiology and Biostatistics, Department of Clinical Research, University Hospital Basel and University of Basel, Basel, Switzerland
| | - Heiner C Bucher
- Basel Institute for Clinical Epidemiology and Biostatistics, Department of Clinical Research, University Hospital Basel and University of Basel, Basel, Switzerland
| | | | | | - Pia Touboul Lundgren
- Département de Santé Publique, Université Côte d'Azur, Centre Hospitalier Universitaire de Nice, Nice, France
| | - Paul Little
- Primary Care and Population Sciences, University of Southampton, Southampton, UK
| | - Andrew W Murphy
- Health Research Board Primary Care Clinical Trial Network Ireland, National University of Ireland Galway, Galway, Ireland
| | - An De Sutter
- Center for Family Medicine UGent, Department of Public Health and Primary Care, Ghent University, Ghent, Belgium
| | - Peter Openshaw
- National Heart and Lung Institute, Imperial College London, London, UK
| | - Menno D de Jong
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Netherlands
| | - Jason T Connor
- ConfluenceStat, Orlando, FL, USA; College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Veerle Matheeussen
- Laboratory of Medical Microbiology, Vaccine & Infectious Disease Institute, University of Antwerp, Antwerp, Belgium; Laboratory of Clinical Microbiology, Antwerp University Hospital, Edegem, Belgium
| | - Margareta Ieven
- Laboratory of Medical Microbiology, Vaccine & Infectious Disease Institute, University of Antwerp, Antwerp, Belgium; Laboratory of Clinical Microbiology, Antwerp University Hospital, Edegem, Belgium
| | - Herman Goossens
- Laboratory of Medical Microbiology, Vaccine & Infectious Disease Institute, University of Antwerp, Antwerp, Belgium; Laboratory of Clinical Microbiology, Antwerp University Hospital, Edegem, Belgium
| | - Theo J Verheij
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, Netherlands
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Inada K, Yamada S, Akiyoshi H, Kojima Y, Iwashita S, Ishigooka J. Long-Term Efficacy and Safety of Brexpiprazole in Elderly Japanese Patients with Schizophrenia: A Subgroup Analysis of an Open-Label Study. Neuropsychiatr Dis Treat 2020; 16:2267-2275. [PMID: 33116525 PMCID: PMC7547788 DOI: 10.2147/ndt.s265173] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 09/17/2020] [Indexed: 11/23/2022] Open
Abstract
PURPOSE This study was performed to assess the long-term efficacy, safety, and tolerability of brexpiprazole in elderly Japanese patients with schizophrenia. METHODS This is a post hoc analysis of a previous open-label study conducted over 56 weeks which consisted of two consecutive phases: a 4-week switching period and a 52-week open-label period. Mean change in the Positive and Negative Syndrome Scale (PANSS) total score, response rates, number and incidence of treatment-emergent adverse events (TEAEs), and other safety parameters were analyzed using descriptive statistics based on age group (elderly, ≥65 and non-elderly, <65). RESULTS This post hoc analysis included 208 de novo patients of which 33 were elderly. The continuation rate in elderly patients was 54.5%, and the mean daily dose and treatment duration of brexpiprazole in elderly patients at week 56 were similar to those of non-elderly patients. The mean change in the PANSS total score from the baseline to week 56 was -13.8 in elderly patients and this improvement was maintained throughout the open-label phase. This outcome was comparable to that of the non-elderly patients (-9.0). The incidence rate of TEAEs was 97.0% in elderly patients and 82.3% in non-elderly patients. Most of the TEAEs were either mild (75.8%) or moderate (18.2%) in severity in the elderly patients and the incidence of TEAEs leading to discontinuation was lower in elderly (9.1%) than in non-elderly patients (13.1%). The most commonly observed adverse events in elderly patients were nasopharyngitis (30.3%) and worsening of schizophrenia (27.3%). The safety profiles in both groups were similar. CONCLUSION Brexpiprazole was shown to be safe and effective in the treatment of elderly Japanese patients with schizophrenia.
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Affiliation(s)
- Ken Inada
- Department of Psychiatry, Tokyo Women's Medical University, Tokyo, Japan
| | - Sakiko Yamada
- Department of Medical Affairs, Otsuka Pharmaceutical Co., Ltd., Tokyo, Japan
| | - Hisashi Akiyoshi
- Department of Medical Affairs, Otsuka Pharmaceutical Co., Ltd., Tokyo, Japan
| | - Yoshitsugu Kojima
- Department of Medical Affairs, Otsuka Pharmaceutical Co., Ltd., Tokyo, Japan
| | - Shuichi Iwashita
- Headquarters of Clinical Development, Otsuka Pharmaceutical Co., Ltd., Osaka, Japan
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Czerniak E, Oberlander TF, Weimer K, Kossowsky J, Enck P. "Placebo by Proxy" and "Nocebo by Proxy" in Children: A Review of Parents' Role in Treatment Outcomes. Front Psychiatry 2020; 11:169. [PMID: 32218746 PMCID: PMC7078585 DOI: 10.3389/fpsyt.2020.00169] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 02/21/2020] [Indexed: 12/12/2022] Open
Abstract
The "placebo (effect) by proxy" (PbP) concept, introduced by Grelotti and Kaptchuk (1), describes a positive effect of a patient's treatment on persons in their surrounding such as family members or healthcare providers, who feel better because the patient is being treated. The PbP effect is a complex dynamic phenomenon which attempts to explain a change in treatment outcome arising from an interaction between a patient and an effect from proxies such as parents, caregivers, physicians or even the media. By extension the effect of the proxy can also have a negative or adverse effect whereby a proxy feels worse when a patient is treated, giving rise to the possibility of a "nocebo (effect) by proxy" (NbP), and by extension can influence a patient's treatment response. While this has yet to be systematically investigated, such an effect could occur when a proxy observes that a treatment is ineffective or is perceived as causing adverse effects leading the patient to experience side effects. In this narrative review, we take these definitions one step further to include the impact of PbP/NbP as they transform to affect the treatment outcome for the patient or child being treated, not just the people surrounding the individual being treated. Following a systematic search of literature on the subject using the Journal of Interdisciplinary Placebo Studies (JIPS) database (https://jips.online) and PubMed (NCBI) resulted in very few relevant studies, especially in children. The effect of PbP per se has been studied in parents and their children for temper tantrums, acupuncture for postoperative symptoms, as well as for neuroprotection in very preterm-born infants. This paper will review the PbP/NbP concepts, show evidence for its presence in children's treatment outcome and introduce clinical implications. We will also offer suggestions for future research to further our understanding of the role of the proxy in promoting or distracting from treatment benefit in children. Increasing an appreciation of the PbP and NbP phenomena and the role of the proxy in children's treatment should improve research study design and ultimately harness them to improve clinical child healthcare.
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Affiliation(s)
- Efrat Czerniak
- Department of Pediatrics, BC Children's Hospital Research Institute, University of British Columbia, Vancouver, BC, Canada
| | - Tim F Oberlander
- Department of Pediatrics, BC Children's Hospital Research Institute, University of British Columbia, Vancouver, BC, Canada
| | - Katja Weimer
- Department of Psychosomatic Medicine and Psychotherapy, Ulm University Medical Center, Ulm, Germany
| | - Joe Kossowsky
- Department of Anesthesiology, Critical Care and Pain Medicine, Harvard Medical School, Boston Children's Hospital, Boston, MA, United States.,Department of Clinical Psychology & Psychotherapy, University of Basel, Basel, Switzerland
| | - Paul Enck
- Department of Psychosomatic Medicine and Psychotherapy, University Medical Hospital Tübingen, Tübingen, Germany
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Enck P, Klosterhalfen S. Placebo Responses and Placebo Effects in Functional Gastrointestinal Disorders. Front Psychiatry 2020; 11:797. [PMID: 33192627 PMCID: PMC7477083 DOI: 10.3389/fpsyt.2020.00797] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/25/2019] [Accepted: 07/24/2020] [Indexed: 12/14/2022] Open
Abstract
Much has been written about the placebo effects in functional gastrointestinal disorders (FGD), especially in irritable bowel syndrome (IBS), driven by the early hypothesis that in randomized controlled trials (RCTs) of IBS, the placebo effect might be specifically high and thus, corrupts the efficacy of novel drugs developed for this condition. This narrative review is based on a specific search method, a database (www.jips.online) developed since 2004 containing more than 4,500 papers (data papers, meta-analyses, systematic reviews, reviews) pertinent to the topic placebo effects/placebo response. Three central questions-deducted from the body of current literature-are addressed to explore the evidence behind this hypothesis: What is the size placebo effect in FGD, especially in IBS, and is it different from the placebo effect seen in other gastrointestinal disorders? Is the placebo effect in FGD different from other functional, non-intestinal disorders, e.g. in other pain syndromes? Is the placebo effect in FGD related to placebo effects seen in psychiatry, e.g. in depression, anxiety disorders, and alike? Following this discussion, a fourth question is raised as the result of the three: What are the consequences of this for future drug trials in FGD? In summary it is concluded that, contrary to common belief and discussion, the placebo effect seen in RCT in FGD is not specifically high and extraordinary as compared to other comparable (i.e. functional) disorders. It shares less than expected commonalities with the placebo effect in psychiatry, and very few predictors have yet been identified that determine its effect size, especially some that are driven by design features of the studies. Current practice of RCT in IBS seems to limit and control the placebo effect quite well, and future trial practice, e.g. head-to-head trial, still offers options to maintain this control, even in the absence of placebos used.
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Affiliation(s)
- Paul Enck
- Department of Internal Medicine VI: Psychosomatic Medicine and Psychotherapy, University Hospital Tübingen, Tübingen, Germany
| | - Sibylle Klosterhalfen
- Department of Internal Medicine VI: Psychosomatic Medicine and Psychotherapy, University Hospital Tübingen, Tübingen, Germany
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Nee J, Sugarman MA, Ballou S, Katon J, Rangan V, Singh P, Zubiago J, Kaptchuk TJ, Lembo A. Placebo Response in Chronic Idiopathic Constipation: A Systematic Review and Meta-Analysis. Am J Gastroenterol 2019; 114:1838-1846. [PMID: 31592782 DOI: 10.14309/ajg.0000000000000399] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Chronic idiopathic constipation (CIC), like other functional gastrointestinal disorders, has been associated with a high placebo response rate. However, the placebo response in randomized controlled trials has not been described. METHODS We conducted a search of the medical literature following the protocol outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement using MEDLINE, EMBASE and EMBASE Classic, Web of Science, and the Cochrane Central Register of Controlled Trials for all drugs used for the treatment of CIC. Two independent reviewers performed eligibility assessment and data extraction. The mean response rate was examined for the following 2 responder endpoints: (i) greater than or equal to 3 complete spontaneous bowel movements (CSBMs)/wk (≥3 CSBMs/wk responders) and (ii) mean increase of ≥1 CSBM/wk compared with baseline (increase in ≥1 CSBM/wk responders). RESULTS A total of 23 placebo-controlled trials met our inclusion criteria and were included in this meta-analysis. The placebo response in CIC trials ranged from 4% to 44%. The magnitude of the placebo response was 13% (95% confidence interval 11%-16%) with the ≥3 CSBM/wk responder endpoint and 28% (95% confidence interval 21%-30%) with the increase of ≥1 in the CSBM responder endpoint. Higher baseline CSBM, older age, and trials with more male participants were significantly associated with a stronger placebo response for both the ≥3 CSBMs/wk endpoint and increase in the ≥1 CSBM/wk endpoint. Trial characteristics such as location (Europe vs Asia/United States) and laxative class (prokinetic vs secretagogue) revealed key differences in the placebo response for both endpoints. The placebo response was not significantly affected by the number of study visits, study duration, year of publication, number of drop outs, or likelihood of receiving active drug. DISCUSSION The placebo response in CIC trials ranges from 4% to 44% depending on the endpoint. Modifying factors of the placebo response include multiple subject and trial characteristics.
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Affiliation(s)
- Judy Nee
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | | | - Sarah Ballou
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Jesse Katon
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Vikram Rangan
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Prashant Singh
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Julia Zubiago
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Ted J Kaptchuk
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Anthony Lembo
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
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Joung JY, Lee JS, Cho JH, Lee DS, Ahn YC, Son CG. The Efficacy and Safety of Myelophil, an Ethanol Extract Mixture of Astragali Radix and Salviae Radix, for Chronic Fatigue Syndrome: A Randomized Clinical Trial. Front Pharmacol 2019; 10:991. [PMID: 31551788 PMCID: PMC6746924 DOI: 10.3389/fphar.2019.00991] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 08/05/2019] [Indexed: 12/12/2022] Open
Abstract
Background: There is a strong demand for therapeutics to treat chronic fatigue syndrome (CFS), although there are limitations. Myelophil, which is a combination of extracts from Astragali Radix and Salviae Miltiorrhizae Radix, has been clinically used to treat fatigue-related disorders in South Korea. We conducted a randomized controlled clinical trial of Myelophil in patients with CFS and evaluated its efficacy and safety in two hospitals. Methods: We enrolled 98 participants (M: 38, F: 60) with CFS in a phase 2 trial of oral Myelophil (2 g daily) or placebo for 12 weeks. The primary end point was a change in the Chalder fatigue scale, as scored by a numeric rating scale (NRS). The secondary end points included changes in the visual analogue scale, fatigue severity scale (FSS), and 36-item short-form health survey (SF-36). Biomarkers of oxidative stress and cytokines were evaluated by blood tests. Results: Ninety-seven participants (48 in the Myelophil group and 49 in the placebo group) completed the trial. An analysis of all participants showed that Myelophil slightly improved fatigue symptoms compared with those of the placebo, but this effect was not statistically significant (p > 0.05 for the NRS, VAS, FSS, and SF-36). By contrast, an analysis of the subpopulation (53 participants, M: 24, F: 29) with severe symptoms (≥63, median NRS value of total participants) showed a statistically significant improvement in fatigue symptoms in the Myelophil group compared with the placebo (p < 0.05 for NRS, FSS, and SF-36). There were no significant changes in the biomarkers for oxidative stress and cytokines before or after the treatment. No Myelophil-related adverse response was observed during the trial. Conclusion: These results support the hypothesis that Myelophil can be a therapeutic candidate to manage CFS and provide the rationale for its progression to a phase 3 clinical trial. Clinical Trial Registration:www.ClinicalTrials.gov, identifier KCT0002317.
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Affiliation(s)
- Jin-Yong Joung
- Liver and Immunology Research Center, Oriental Medical Collage of Daejeon University, Daejeon, South Korea
| | - Jin-Seok Lee
- Liver and Immunology Research Center, Oriental Medical Collage of Daejeon University, Daejeon, South Korea
| | - Jung-Hyo Cho
- Liver and Immunology Research Center, Oriental Medical Collage of Daejeon University, Daejeon, South Korea
| | - Dong-Soo Lee
- Department of Internal Medicine, Daejeon St. Mary's Hospital of Catholic University, Daejeon, South Korea
| | - Yo-Chan Ahn
- Department of Health Service Management, Daejeon University, Daejeon, South Korea
| | - Chang-Gue Son
- Liver and Immunology Research Center, Oriental Medical Collage of Daejeon University, Daejeon, South Korea
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Colloca L, Wang Y, Martinez PE, Christy Chang YP, Ryan KA, Hodgkinson C, Goldman D, Dorsey SG. OPRM1 rs1799971, COMT rs4680, and FAAH rs324420 genes interact with placebo procedures to induce hypoalgesia. Pain 2019; 160:1824-1834. [PMID: 31335650 PMCID: PMC6668362 DOI: 10.1097/j.pain.0000000000001578] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Genetics studies on the placebo hypoalgesic effect highlight a promising link between single nucleotide polymorphisms (SNPs) in the dopamine, opioid, and endocannabinoid genes and placebo hypoalgesia. However, epistasis and replication studies are missing. In this study, we expanded on previous findings related to the 3 SNPs in the opioid receptor mu subunit (OPRM1 rs1799971), catechol-O-methyltransferase (COMT rs4680), and fatty acid amide hydrolase (FAAH rs324420) genes associated with placebo hypoalgesia and tested the effect of a 3-way interaction on placebo hypoalgesia. Using 2 well-established placebo procedures (verbal suggestion and learning paradigm), we induced significant placebo hypoalgesic effects in 160 healthy participants. We found that individuals with OPRM1 AA combined with FAAH Pro/Pro and those carrying COMT met/met together with FAAH Pro/Pro showed significant placebo effects. Participants with COMT met/val alleles showed significant placebo effects independently of OPRM1 and FAAH allele combinations. Finally, the model that included the placebo procedure and genotypes predicted placebo responsiveness with a higher accuracy (area under the curve, AUC = 0.773) as compared to the SNPs alone indicating that genetic variants can only partially explain the placebo responder status. Our results suggest that the endogenous mu-opioid system with a larger activation in response to pain in the met/val allele carriers as well as the synergism between endogenous mu-opioid system and cannabinoids might play the most relevant role in driving hypoalgesic responses. Future epistasis studies with larger sample sizes will help us to fully understand the complexity of placebo effects and explain the mechanisms that underlie placebo responsiveness.
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Affiliation(s)
- Luana Colloca
- Department of Pain and Translational Symptom Science, School of Nursing, University of Maryland, Baltimore, USA
- Departments of Anesthesiology and Psychiatry, School of Medicine, University of Maryland, Baltimore, University of Maryland, Baltimore, USA
- Center to Advance Chronic Pain Research, University of Maryland, Baltimore, USA
| | - Yang Wang
- Department of Pain and Translational Symptom Science, School of Nursing, University of Maryland, Baltimore, USA
- Center to Advance Chronic Pain Research, University of Maryland, Baltimore, USA
| | | | | | | | - Colin Hodgkinson
- Laboratory of Neurogenetics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, 20892, USA
| | - David Goldman
- Laboratory of Neurogenetics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, 20892, USA
| | - Susan G. Dorsey
- Department of Pain and Translational Symptom Science, School of Nursing, University of Maryland, Baltimore, USA
- Departments of Anesthesiology and Psychiatry, School of Medicine, University of Maryland, Baltimore, University of Maryland, Baltimore, USA
- Center to Advance Chronic Pain Research, University of Maryland, Baltimore, USA
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Franconi F, Campesi I, Colombo D, Antonini P. Sex-Gender Variable: Methodological Recommendations for Increasing Scientific Value of Clinical Studies. Cells 2019; 8:E476. [PMID: 31109006 PMCID: PMC6562815 DOI: 10.3390/cells8050476] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 05/07/2019] [Accepted: 05/09/2019] [Indexed: 02/08/2023] Open
Abstract
There is a clear sex-gender gap in the prevention and occurrence of diseases, and in the outcomes and treatments, which is relevant to women in the majority of cases. Attitudes concerning the enrollment of women in randomized clinical trials have changed over recent years. Despite this change, a gap still exists. This gap is linked to biological factors (sex) and psycho-social, cultural, and environmental factors (gender). These multidimensional, entangled, and interactive factors may influence the pharmacological response. Despite the fact that regulatory authorities recognize the importance of sex and gender, there is a paucity of research focusing on the racial/ethnic, socio-economic, psycho-social, and environmental factors that perpetuate disparities. Research and clinical practice must incorporate all of these factors to arrive at an intersectional and system-scenario perspective. We advocate for scientifically rigorous evaluations of the interplay between sex and gender as key factors in performing clinical trials, which are more adherent to real-life. This review proposes a set of 12 rules to improve clinical research for integrating sex-gender into clinical trials.
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Affiliation(s)
- Flavia Franconi
- Laboratory of Sex-gender Medicine, National Institute of Biostructures and Biosystems, 07100 Sassari, Italy.
| | - Ilaria Campesi
- Laboratory of Sex-gender Medicine, National Institute of Biostructures and Biosystems, 07100 Sassari, Italy.
- Dipartimento di Scienze Biomediche, Università degli Studi di Sassari, 07100 Sassari, Italy.
| | - Delia Colombo
- Value and Access Head, Novartis Italia, 21040 Origgio, Italy.
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Enck P, Klosterhalfen S. Does Sex/Gender Play a Role in Placebo and Nocebo Effects? Conflicting Evidence From Clinical Trials and Experimental Studies. Front Neurosci 2019; 13:160. [PMID: 30886569 PMCID: PMC6409330 DOI: 10.3389/fnins.2019.00160] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 02/12/2019] [Indexed: 12/12/2022] Open
Abstract
Sex has been speculated to be a predictor of the placebo and nocebo effect for many years, but whether this holds true or not has rarely been investigated. We utilized a placebo literature database on various aspects of the genuine placebo/nocebo response. In 2015, we had extracted 75 systematic reviews, meta-analyses, and meta-regressions performed in major medical areas (neurology, psychiatry, internal medicine). These meta-analyses were screened for whether sex/gender differences had been noted to contribute to the placebo/nocebo effect: in only 3 such analyses female sex was associated with a higher placebo effect, indicating poor evidence for a contribution of sex to it in RCTs. This was updated with another set of meta-analyses for the current review, but did not change the overall conclusion. The same holds true for 18 meta-analyses investigating adverse event (nocebo) reporting in RCT in the placebo arm of trials. We also screened our database for papers referring to sex/gender and the placebo effect in experimental studies, and identified 28 papers reporting 29 experiments. Their results can be summarized as follows: (a) Despite higher sensitivity of pain in females, placebo analgesia is easier to elicit in males; (b) It appears that conditioning is effective specifically eliciting nocebo effects; (c) Conditioning works specifically well to elicit placebo and nocebo effects in females and with nausea; (d) Verbal suggestions are not sufficient to induce analgesia in women, but work in men. These results will be discussed with respect to the question why nausea and pain may be prone to be responsive to sex/gender differences, while other symptoms are less. Lastly, we will discuss the apparent discrepancy between RCT with low relevance of sex, and higher relevance of sex in specific experimental settings. We argue that the placebo response is predominantly the result of a conditioning (learning) response in females, while in males it predominantly may be generated via (verbal) manipulating of expectancies. In RCT therefore, the net outcome of the intervention may be the same despite different mechanisms generating the placebo effect between the sexes, while in experimental work when both pathways are separated and explicitly explored, such differences may surface.
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Affiliation(s)
- Paul Enck
- Department of Internal Medicine VI: Psychosomatic Medicine and Psychotherapy, University Hospital Tübingen, Tübingen, Germany
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Skvortsova A, Veldhuijzen DS, Kloosterman IEM, Meijer OC, van Middendorp H, Pacheco-Lopez G, Evers AWM. Conditioned hormonal responses: A systematic review in animals and humans. Front Neuroendocrinol 2019; 52:206-218. [PMID: 30590067 DOI: 10.1016/j.yfrne.2018.12.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 11/21/2018] [Accepted: 12/21/2018] [Indexed: 12/09/2022]
Abstract
In contrast to classical conditioning of physiological responses such as immune responses and drug effects, only a limited number of studies investigated classical conditioning of endocrine responses. The present paper is the first systematic review that integrates evidence from animal and human trials regarding the possibility to condition the endocrine responses. Twenty-six animal and eight human studies were included in the review. We demonstrated that there is accumulating evidence that classical conditioning processes are able to influence specific endocrine responses, such as cortocosterone/cortisol and insulin, while more limited evidence exists for other hormones. Animal and human studies were generally consistent in their findings; however, the limited number of human studies makes it difficult to generalize and translate the results of animal research to humans. Next to methodological recommendations for future studies, we suggest several ways how classically conditioned endocrine responses can be used in clinical practice.
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Affiliation(s)
- Aleksandrina Skvortsova
- Health, Medical and Neuropsychology Unit, Faculty of Social and Behavioural Sciences, Leiden University, 2333 AK Leiden, the Netherlands; Leiden Institute for Brain and Cognition, 2300 RC Leiden, the Netherlands.
| | - Dieuwke S Veldhuijzen
- Health, Medical and Neuropsychology Unit, Faculty of Social and Behavioural Sciences, Leiden University, 2333 AK Leiden, the Netherlands; Leiden Institute for Brain and Cognition, 2300 RC Leiden, the Netherlands
| | - Iris E M Kloosterman
- Health, Medical and Neuropsychology Unit, Faculty of Social and Behavioural Sciences, Leiden University, 2333 AK Leiden, the Netherlands
| | - Onno C Meijer
- Department of Medicine, Division of Endocrinology, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands
| | - Henriët van Middendorp
- Health, Medical and Neuropsychology Unit, Faculty of Social and Behavioural Sciences, Leiden University, 2333 AK Leiden, the Netherlands; Leiden Institute for Brain and Cognition, 2300 RC Leiden, the Netherlands
| | - Gustavo Pacheco-Lopez
- Health, Medical and Neuropsychology Unit, Faculty of Social and Behavioural Sciences, Leiden University, 2333 AK Leiden, the Netherlands; Department of Health Sciences, Campus Lerma, Metropolitan Autonomous University (UAM), 52006 Lerma, Edo Mex, Mexico
| | - Andrea W M Evers
- Health, Medical and Neuropsychology Unit, Faculty of Social and Behavioural Sciences, Leiden University, 2333 AK Leiden, the Netherlands; Leiden Institute for Brain and Cognition, 2300 RC Leiden, the Netherlands; Department of Psychiatry, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands
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Weimer K, Hahn E, Mönnikes N, Herr AK, Stengel A, Enck P. Are Individual Learning Experiences More Important Than Heritable Tendencies? A Pilot Twin Study on Placebo Analgesia. Front Psychiatry 2019; 10:679. [PMID: 31620030 PMCID: PMC6759638 DOI: 10.3389/fpsyt.2019.00679] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 08/22/2019] [Indexed: 12/11/2022] Open
Abstract
Objective: Predicting who will be a placebo responder is a prerequisite to maximize placebo effects in pain treatment and to minimize them in clinical trials. First evidence exists that genetics could affect placebo effects. However, a classical twin study to estimate the relative contribution of genetic influences compared to common and individual environmental influences in explaining interindividual differences in placebo responsiveness has yet not been performed. Methods: In a first explorative twin study, 25 monozygotic (MZ) and 14 dizygotic (DZ) healthy twin pairs (27.5 ± 7.7 years; 73% female) were conditioned to the efficacy of a placebo analgesic ointment with an established heat pain paradigm on their non-dominant arm. Placebo analgesia was then tested on their dominant arm. Furthermore, warmth detection thresholds (WDTs) and heat pain thresholds (HPTs) were assessed, and participants filled in questionnaires for the assessment of psychological traits such as depression, anxiety, optimism, pain catastrophizing, and sensitivity to reward and punishment. Their expectations were determined with a visual analog scale. Results: There was a small but significant placebo analgesic effect in both MZ and DZ twins. Estimates of heritability were moderate for WDT only but negligible for HPT, the conditioning response, and placebo analgesia. Common environment did not explain any variance, and the individual environment explained the largest parts. Therefore, the placebo analgesia response can be seen as influenced by individual learning experiences during the conditioning procedure, whereas other variables assessed were not associated. Conclusions: Compared to the individual learning experience, genetic influences seem to play a minor role in explaining variation in placebo analgesia in this experimental paradigm. However, our results are restricted to placebo effects through conditioning on pain in healthy volunteers and should be replicated in larger samples and in patients. Furthermore, potential gene-environment interactions should be further investigated.
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Affiliation(s)
- Katja Weimer
- Department of Psychosomatic Medicine and Psychotherapy, Ulm University Medical Center, Ulm, Germany.,Department of Psychosomatic Medicine and Psychotherapy, Medical University Hospital Tübingen, Tübingen, Germany
| | - Elisabeth Hahn
- Department of Psychology, Saarland University, Saarbruecken, Germany
| | - Nils Mönnikes
- Charité Center for Internal Medicine and Dermatology, Department for Psychosomatic Medicine, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Ann-Kathrin Herr
- Department of Psychosomatic Medicine and Psychotherapy, Medical University Hospital Tübingen, Tübingen, Germany
| | - Andreas Stengel
- Department of Psychosomatic Medicine and Psychotherapy, Medical University Hospital Tübingen, Tübingen, Germany.,Charité Center for Internal Medicine and Dermatology, Department for Psychosomatic Medicine, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Paul Enck
- Department of Psychosomatic Medicine and Psychotherapy, Medical University Hospital Tübingen, Tübingen, Germany
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Abstract
The issue of placebo response and the extent of its effect on psychotherapy is complex for two specific reasons: i) Current standards for drug trials, e.g., true placebo interventions, double-blinding, cannot be applied to most psychotherapy techniques, and ii) some of the "nonspecific effects" in drug therapy have very specific effects in psychotherapy, such as the frequency and intensity of patient-therapist interaction. In addition, different psychotherapy approaches share many such specific effects (the "dodo bird verdict") and lack specificity with respect to therapy outcome. Here, we discuss the placebo effect in psychotherapy under four aspects: a) nonspecific factors shared with drug therapy (context factors); b) nonspecific factors shared among all psychotherapy traditions (common factors); c) specific placebo-controlled options with different psychotherapy modalities; and d) nonspecific control options for the specific placebo effect in psychotherapy. The resulting framework proposes that the exploration and enumeration of context factors, common factors, and specific factors contributes to the placebo effects in psychotherapy.
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Affiliation(s)
- Paul Enck
- Psychosomatic Medicine and Psychotherapy, Department of Internal Medicine VI, University Hospital Tübingen, Tübingen, Germany
| | - Stephan Zipfel
- Psychosomatic Medicine and Psychotherapy, Department of Internal Medicine VI, University Hospital Tübingen, Tübingen, Germany
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Abstract
In this review, we explored different ways of controlling the placebo effects in clinical trials and described various factors that may increase/decrease the placebo effect in randomized placebo-controlled trials. These factors can be subdivided into four groups, and while not all factors are effective in every study and under all clinical conditions, they show on the whole that - even under the ideal condition of drug therapy, where blinded placebo provision is much easier and warranted than in, e.g., psychotherapy - many factors need to be controlled to ascertain that the goal of the clinical trials, fair assessment of superiority of the drug over placebo in placebo-controlled trials and fair assessment of non-inferiority of the drug compared to another drug in comparator trials, is reached. Ignorance towards the placebo effect, which was common in the past, is no longer acceptable; instead, it should be the goal of all therapeutic trials to minimize the placebo effect in clinical trials, while utilizing and maximizing it in clinical routine.
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Affiliation(s)
- Paul Enck
- Department of Internal Medicine VI: Psychosomatic Medicine and Psychotherapy , University Hospital Tübingen, Tübingen, Germany.
| | - Sibylle Klosterhalfen
- Department of Internal Medicine VI: Psychosomatic Medicine and Psychotherapy , University Hospital Tübingen, Tübingen, Germany
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Geers AL, Briñol P, Petty RE. An Analysis of the Basic Processes of Formation and Change of Placebo Expectations. REVIEW OF GENERAL PSYCHOLOGY 2018. [DOI: 10.1037/gpr0000171] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Placebo effects are the measurable psychological, biological, and behavioral changes that can result from expecting a treatment to be effective. Here we argue that not all expectations are created equally and there is much to learn by clarifying the psychological processes that underlie the expectations that cause placebo effects. It is proposed that the formation and change of placebo expectations can be understood from the standpoint of a general psychological model describing the basic processes of mental change. Specifically, we use the Elaboration Likelihood Model to explain how placebo-relevant variables (e.g., doctor’s lab coat, drug price, number and color of pills, patient’s mood) can work to affect expectations. Clarifying the antecedent processes responsible for placebo expectations leads to new insights regarding placebo effects, including their durability, directionality, and ability to alter subsequent behaviors (e.g., treatment adherence). A key point from our approach is that expectations causing placebo effects can be formed under high or low thought. High-thought expectations should be more likely to resist change, last over time, predict placebo effects better than low-thought expectations, and have a greater likelihood to alter subsequent behaviors. We conclude by describing a variety of theoretical innovations that this new conceptualization raises and suggest novel paths for research and application.
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Affiliation(s)
| | - Pablo Briñol
- Department of Social Psychology and Methodology, Universidad Autónoma de Madrid
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Factors Associated With Response to Placebo in Patients With Irritable Bowel Syndrome and Constipation. Clin Gastroenterol Hepatol 2018; 16:1738-1744.e1. [PMID: 29654913 PMCID: PMC6414074 DOI: 10.1016/j.cgh.2018.04.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 03/20/2018] [Accepted: 04/02/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS A high proportion of patients with irritable bowel syndrome (IBS) respond to placebo in clinical trials (estimated at about 40%). We aimed to identify factors that contribute to the high placebo response rate using data from a placebo-controlled trial of patients with IBS. METHODS We performed a retrospective analysis of 599 women with IBS with constipation who were in the placebo group of a 12-week, randomized, double-blind, phase 3 trial of the experimental medication renzapride. Primary analyses evaluated frequency of abdominal pain in patients who received placebo, defined as ≥30% pain improvement from baseline for ≥6 of the 12 study weeks. We performed backward elimination regression with bootstrapping to identify factors associated with response to placebo. RESULTS In the placebo group, 29.0% of the patients had an abdominal pain response. Factors associated with a response to placebo were baseline variation in abdominal pain (odds ratio [OR], 1.71), maximum baseline pain severity (OR, 1.34), and placebo response in study week 2 (OR, 2.23) or week 3 (OR, 3.69). Factors associated with lack of response to placebo were number of baseline complete spontaneous bowel movements (OR, 0.73; P = .019) and final baseline pain ratings (OR, 0.73; P < .001). CONCLUSIONS We identified factors associated with a response in abdominal pain to placebo using original data from an IBS clinical trial. Baseline factors associated with the placebo response in women with IBS and constipation included variation in baseline pain symptoms, severity of baseline symptoms, and early improvement of abdominal pain. These findings have significant implications for clinical trial design.
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Zunhammer M, Gerardi M, Bingel U. The effect of dopamine on conditioned placebo analgesia in healthy individuals: a double-blind randomized trial. Psychopharmacology (Berl) 2018; 235:2587-2595. [PMID: 29943093 DOI: 10.1007/s00213-018-4951-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 06/18/2018] [Indexed: 12/12/2022]
Abstract
RATIONALE Better means to control placebo effects are key to optimizing treatment outcomes. Dopamine-based reward and learning mechanisms have been hypothesized to drive placebo effects. Here, we tested whether dopamine augmentation can modulate learned placebo effects. METHODS We performed a randomized, double-blind parallel group study with 70 healthy adult participants to test whether a single oral dose of the dopamine precursor levodopa/carbidopa (100/25 mg) administered before the acquisition of conditioned placebo analgesia enhances the placebo response in an established experimental placebo model using heat pain. RESULTS Overall, the observed levels of placebo analgesia in our sample were low and not statistically significant. Levodopa, compared to placebo, only led to a marginal increase in placebo analgesia. Female participants tended to show larger placebo responses than male participants. Within the female subgroup, levodopa showed small-to-moderate effects on placebo analgesia; however, this effect was not statistically significant. CONCLUSIONS In summary, the present study could not provide evidence for a placebo augmenting effect of levodopa-enhanced dopamine levels in healthy subjects. Further studies are needed to elucidate whether placebo enhancement can be achieved through dopamine augmentation.
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Affiliation(s)
- Matthias Zunhammer
- Klinik für Neurologie, Universitätsklinikum Essen, Hufelandstraße 55, 45147, Essen, Germany.
| | - Magnus Gerardi
- Klinik für Neurologie, Universitätsklinikum Essen, Hufelandstraße 55, 45147, Essen, Germany
| | - Ulrike Bingel
- Klinik für Neurologie, Universitätsklinikum Essen, Hufelandstraße 55, 45147, Essen, Germany
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Damien J, Colloca L, Bellei-Rodriguez CÉ, Marchand S. Pain Modulation: From Conditioned Pain Modulation to Placebo and Nocebo Effects in Experimental and Clinical Pain. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2018; 139:255-296. [PMID: 30146050 DOI: 10.1016/bs.irn.2018.07.024] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Accumulating evidence reveal important applications of endogenous pain modulation assessment in healthy controls and in patients in clinical settings, as dysregulations in the balance of pain modulatory circuits may facilitate pain and promote chronification of pain. This article reviews data on pain modulation, focusing on the mechanisms and translational aspects of pain modulation from conditioned pain modulation (CPM) to placebo and nocebo effects in experimental and clinical pain. The specific roles of expectations, learning, neural and neurophysiological mechanisms of the central nervous system are briefly reviewed herein. The interaction between CPM and placebo systems in pain inhibitory pathways is highly relevant in the clinic and in randomized controlled trials yet remains to be clarified. Examples of clinical implications of CPM and its relationship to placebo and nocebo effects are provided. A greater understanding of the role of pain modulation in various pain states can help characterize the manifestation and development of chronic pain and assist in predicting the response to pain-relieving treatments. Placebo and nocebo effects, intrinsic to every treatment, can be used to develop personalized therapeutic approaches that improve clinical outcomes while limiting unwanted effects.
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Affiliation(s)
- Janie Damien
- Research Center of the Centre hospitalier universitaire de Sherbrooke (CHUS), Department of Surgery, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Luana Colloca
- Department of Pain Translational Symptom Science, School of Nursing, University of Maryland, Baltimore, MD, United States; Departments of Psychiatry and Anesthesiology, School of Medicine, University of Maryland, Baltimore, MD, United States
| | - Carmen-Édith Bellei-Rodriguez
- Research Center of the Centre hospitalier universitaire de Sherbrooke (CHUS), Department of Surgery, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Serge Marchand
- Research Center of the Centre hospitalier universitaire de Sherbrooke (CHUS), Department of Surgery, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada; Fonds de Recherche du Québec-Santé (FRQS), Montréal, QC, Canada.
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Doria A, Stohl W, Schwarting A, Okada M, Scheinberg M, van Vollenhoven R, Hammer AE, Groark J, Bass D, Fox NL, Roth D, Gordon D. Efficacy and Safety of Subcutaneous Belimumab in Anti-Double-Stranded DNA-Positive, Hypocomplementemic Patients With Systemic Lupus Erythematosus. Arthritis Rheumatol 2018; 70:1256-1264. [PMID: 29671280 PMCID: PMC6099508 DOI: 10.1002/art.40511] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 03/22/2018] [Indexed: 01/23/2023]
Abstract
OBJECTIVE To investigate the efficacy and safety of belimumab, a human immunoglobulin monoclonal antibody against B lymphocyte stimulator, in a subset of patients with systemic lupus erythematosus (SLE) who were hypocomplementemic (C3 <90 mg/dl and/or C4 <10 mg/dl) and anti-double-stranded DNA (anti-dsDNA) positive (≥30 IU/ml) at baseline. METHODS In this phase III, double-blind, placebo-controlled study (BEL112341; ClinicalTrials.gov identifier: NCT01484496), patients with moderate to severe SLE (Safety of Estrogens in Lupus Erythematosus National Assessment version of the Systemic Lupus Erythematosus Disease Activity Index [SELENA-SLEDAI] score ≥8) were randomized (2:1) to receive weekly subcutaneous (SC) belimumab 200 mg or placebo, plus standard SLE therapy, for 52 weeks. The primary end point was SLE Responder Index 4 (SRI-4) response rate at week 52. Secondary end points were time to severe flare and reduction in corticosteroid dose (weeks 40-52). Safety was assessed throughout. RESULTS Of the 836 patients in the intent-to-treat (ITT) population, 356 were hypocomplementemic and anti-dsDNA positive at baseline (108 in the placebo group and 248 in the SC belimumab 200 mg group). Compared with placebo, the belimumab group contained more SRI-4 responders (47.2% versus 64.6%; P = 0.0014), had a lower incidence of severe flare according to the SELENA-SLEDAI flare index (31.5% versus 14.1%), and had a greater percentage of patients who reduced corticosteroid dosage by ≥25% to ≤7.5 mg/day during weeks 40-52 (11.4% versus 20.7%; P = 0.0844). Adverse events (AEs) were similar between treatment groups. CONCLUSION Our findings indicate that in hypocomplementemic, anti-dsDNA-positive SLE patients, weekly SC belimumab 200 mg significantly improves SRI-4 response, decreases severe flare incidence, and reduces corticosteroid use versus placebo; a trend toward greater benefit compared with the overall ITT population was observed. AEs were consistent with the known safety profile of belimumab.
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Affiliation(s)
| | - W. Stohl
- University of Southern CaliforniaLos Angeles
| | - A. Schwarting
- University Medical Center of Johannes Gutenberg UniversityMainzGermany
| | - M. Okada
- St. Luke's International UniversityTokyoJapan
| | | | | | - A. E. Hammer
- GlaxoSmithKlineResearch Triangle ParkNorth Carolina
| | - J. Groark
- GlaxoSmithKlineCollegevillePennsylvania
- Present address:
Aclaris TherapeuticsWaynePennsylvania
| | - D. Bass
- GlaxoSmithKlineCollegevillePennsylvania
- Present address:
Aclaris TherapeuticsWaynePennsylvania
| | - N. L. Fox
- GlaxoSmithKlineRockvilleMaryland
- Present address:
IndiviorRichmondVirginia
| | - D. Roth
- GlaxoSmithKlineCollegevillePennsylvania
- Present address:
Aclaris TherapeuticsWaynePennsylvania
| | - D. Gordon
- GlaxoSmithKlineCollegevillePennsylvania
- Present address:
Aclaris TherapeuticsWaynePennsylvania
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Woitalla D, Dunac A, Safavi A, Ceravolo MG, Gomez Esteban JC, Pavese N, Asgharnejad M, Joeres L, Schuller JC, Chaudhuri KR. A noninterventional study evaluating the effectiveness of rotigotine and levodopa combination therapy in younger versus older patients with Parkinson's disease. Expert Opin Pharmacother 2018; 19:937-945. [PMID: 29916262 DOI: 10.1080/14656566.2018.1480721] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND PD0013 was a 6-month noninterventional study in clinical practice comparing effectiveness/tolerability of rotigotine+levodopa in younger (<70 years) vs. older (≥70 years) Parkinson's disease (PD) patients. METHODS Patients previously received levodopa for ≥6 months as monotherapy/in combination with another dopamine-agonist (DA). Primary variable: Unified PD Rating Scale (UPDRS) Part-II change from baseline to end-of-observation-period (EOP). RESULTS 91 younger/99 older patients started rotigotine; 68 younger/62 older patients completed the study. Most switched from levodopa+another DA. Addition of rotigotine as first DA was more common in older patients (20.2% vs.15.4%). Mean ± SD rotigotine-exposure: 6.1 ± 3.4 mg/24h younger vs. 4.9 ± 2.4 mg/24h older. Eleven patients changed levodopa dose. At EOP, improvement in mean UPDRS-II was greater in younger patients (p = 0.0289). UPDRS-II responder-rate (≥20% decrease in UPDRS-II score) was higher in younger patients (42.3% vs. 25.9%). Improvement across age groups was similar on PD Sleep Scale-2 and Clinical Global Impressions-Improvement Scale. Adverse drug reactions (ADRs), and discontinuations because of ADRs, were more common among older patients. There were no new safety signals. CONCLUSIONS Despite low rotigotine doses, when added to levodopa/switched from levodopa+another DA, rotigotine led to greater improvement in UPDRS-II in younger patients (<70 years). Individual patient data revealed clinically meaningful improvements in UPDRS-II in both groups.
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Affiliation(s)
- Dirk Woitalla
- a Department of Neurology , St. Joseph Hospital, Ruhr-University , Bochum , Germany
| | | | - Ali Safavi
- c Private Neurological Practice , Alzenau , Germany
| | - Maria-Gabriella Ceravolo
- d Department of Experimental and Clinical Medicine , Politecnica delle Marche University , Ancona , Italy
| | | | | | | | | | | | - K Ray Chaudhuri
- j National Parkinson Foundation Centre of Excellence and The Maurice Wohl Clinical Neuroscience Institute, King's College London and King's College Hospital , London , UK
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Mulhall JP, Carlsson M, Stecher V, Tseng LJ. Predictors of Erectile Function Normalization in Men With Erectile Dysfunction Treated With Placebo. J Sex Med 2018; 15:866-872. [PMID: 29753799 DOI: 10.1016/j.jsxm.2018.03.089] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 03/15/2018] [Accepted: 03/30/2018] [Indexed: 11/19/2022]
Abstract
BACKGROUND Clinical study and practice data have shown sildenafil improves sexual function in men with erectile dysfunction (ED). However, some men treated with placebo in double-blind, placebo-controlled sildenafil studies also report improved erectile function as measured by International Index of Erectile Function (IIEF)-Erectile Function Domain (EFD) scores. AIM This analysis estimated the relationship between post-baseline IIEF-EFD scores and demographic variables, including co-morbidities, in men with ED receiving placebo in flexible-dose sildenafil studies. METHODS Placebo-treated participants in the intent-to-treat population of 42 double-blind, placebo-controlled, flexible-dose, sildenafil studies were included. A participant was classified as a placebo responder if the IIEF-EFD score was ≥26 at the last visit. OUTCOMES Variables assessed were age (<45, 45-64, ≥65 years), race, body mass index, co-morbidities (cardiovascular disease/hypertension, diabetes mellitus, depression), date the last study dose was taken, study completion date, ED etiology (psychogenic, organic, mixed), history of cigarette smoking, ED duration, baseline IIEF-EFD score (≤10, 11-16, ≥17), and treatment duration. Stepwise multivariate logistic regression models assessed the odds of being a responder vs a non-responder for each variable. RESULTS A total of 4,360 men were included; 13.5% were responders. Odds estimates indicated the largest likelihood of placebo response occurred in men who were black (odds = 20.2, P < .0001), were younger than 45 years (odds = 7.3, P < .0001), had mild ED (baseline IIEF-EFD ≥17; odds >100, P < .0001), and did not have diabetes (odds = 4.5, P < .0001). The likelihood of a placebo response decreased as ED duration increased (odds = 0.74, P < .0001). The frequency of common adverse events was similar between placebo responders and non-responders. CLINICAL TRANSLATION These findings contribute to the improved understanding of predictors of placebo response in sildenafil clinical studies. Elucidation of these factors may contribute to the development of further interventions and treatment strategies and best practices for clinical trials. STRENGTHS AND CONCLUSIONS Strengths of this analysis include the large and diverse population and the duration of follow-up. Limitations include those associated with retrospective analyses and the inability to ascertain to what extent other demographic factors might have contributed to the placebo responses or how these placebo responses might be related to the natural course of ED. CONCLUSIONS Certain demographics, co-morbidities, and condition characteristics predicted the odds of a placebo response in sildenafil clinical studies of ED. Underlying reasons behind a placebo response warrant further evaluation. Mulhall JP, Carlsson M, Stecher V, et al. Predictors of Erectile Function Normalization in Men With Erectile Dysfunction Treated With Placebo. J Sex Med 2018;15:866-872.
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Affiliation(s)
- John P Mulhall
- Memorial Sloan Kettering Cancer Center, New York, NY, USA.
| | | | - Vera Stecher
- Global Product Development, Pfizer Inc, New York, NY, USA
| | - Li-Jung Tseng
- Global Product Development, Pfizer Inc, New York, NY, USA
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Peerdeman K, Tekampe J, van Laarhoven A, van Middendorp H, Rippe R, Peters M, Evers A. Expectations about the effectiveness of pain- and itch-relieving medication administered via different routes. Eur J Pain 2018; 22:774-783. [PMID: 29266544 PMCID: PMC5873387 DOI: 10.1002/ejp.1163] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/21/2017] [Indexed: 01/12/2023]
Abstract
BACKGROUND Placebo effects on pain have been found to vary in size for different routes of medication administration (e.g. oral vs. injection). This has important implications for both clinical research and practice. To enhance our understanding of these differential placebo effects, research on the underlying expectations about multiple routes and symptoms other than pain is vital. METHODS A cross-sectional, Internet-based survey was conducted in a representative sample of the Dutch population (n = 508). Respondents rated the expected effectiveness of pain- and itch-relieving medication in six forms, representing oral, injection and topical routes of administration. RESULTS Injected medication was expected to be most effective for relieving pain, and topical medication for relieving itch. Furthermore, exploratory analyses showed that injections were expected to have the most rapid onset and long-lasting effects, and to be most frightening and expensive, while topical medication was expected to be the safest and the easiest to use, and oral medication was expected to have the most side effects. Higher expected effectiveness was moderately associated with expectations of more rapid onset and long-lasting effects, and better safety and ease of use. Associations of expected effectiveness with respondent characteristics (e.g. medication use and personality characteristics) were statistically small or nonsignificant. CONCLUSIONS Expected effectiveness of medication differed depending on route of administration and targeted symptom. These findings have important implications for the design and interpretation of clinical trials and suggest that medication effects might be enhanced by prescribing medicine via the route that patients expect to be most effective for their complaint. SIGNIFICANCE Differences in the expected effectiveness of medication depend on the route of administration (oral, injection, topical) and targeted symptom (pain, itch). These findings have important implications for clinical practice and the design and interpretation of clinical trials.
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Affiliation(s)
- K.J. Peerdeman
- Health, Medical and Neuropsychology UnitLeiden UniversityThe Netherlands
- Leiden Institute for Brain and CognitionLeiden UniversityThe Netherlands
| | - J. Tekampe
- Health, Medical and Neuropsychology UnitLeiden UniversityThe Netherlands
- Leiden Institute for Brain and CognitionLeiden UniversityThe Netherlands
| | - A.I.M. van Laarhoven
- Health, Medical and Neuropsychology UnitLeiden UniversityThe Netherlands
- Leiden Institute for Brain and CognitionLeiden UniversityThe Netherlands
- Department of PsychiatryLeiden University Medical CenterThe Netherlands
| | - H. van Middendorp
- Health, Medical and Neuropsychology UnitLeiden UniversityThe Netherlands
- Leiden Institute for Brain and CognitionLeiden UniversityThe Netherlands
| | - R.C.A. Rippe
- Centre for Child and Family StudiesLeiden UniversityThe Netherlands
| | - M.L. Peters
- Department of Clinical Psychological ScienceMaastricht UniversityThe Netherlands
| | - A.W.M. Evers
- Health, Medical and Neuropsychology UnitLeiden UniversityThe Netherlands
- Leiden Institute for Brain and CognitionLeiden UniversityThe Netherlands
- Department of PsychiatryLeiden University Medical CenterThe Netherlands
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