Dataset Information

Run-in periods and clinical outcomes of antipsychotics in dementia: A meta-epidemiological study of placebo-controlled trials.

ABSTRACT:

Purpose

Run-in periods are used to identify placebo-responders and washout. Our aim was to assess the association of run-in periods with clinical outcomes of antipsychotics in dementia.

Methods

We searched randomized placebo-controlled trials of conventional and atypical antipsychotics for neuropsychiatric symptoms (NPS) in dementia in electronic sources and references of selected articles. We extracted (a) the presence of a run-in period, use of placebo/investigated drug during run-in (versus washout only), and run-in duration (1 week or more) and (b) the reduction in NPS, number of participants with somnolence, extrapyramidal symptoms (EPS), and deaths per treatment group. We pooled clinical outcomes comparing antipsychotic and placebo groups in trials with and without run-in.

Results

We identified 35 trials. Twenty-nine trials used run-in. The pooled standardized mean difference in the reduction of NPS was -0.170 (95% CI, -0.227 to -0.112) in trials with run-in and -0.142 (95% CI, -0.331 to 0.047) in trials without run-in. The pooled odds ratio for somnolence was 2.8 (95% CI, 2.3-3.5) in trials with run-in and 3.5 (95% CI, 1.2-10.7) in trials without run-in; for EPS, these ORs were 1.8 (95% CI, 1.4-2.2) and 2.0 (95% CI, 1.3-3.1) respectively, and for mortality 1.4 (95% CI, 1.0-2.0) and 1.6 (95% CI, 0.7-3.4). The use of placebo/investigated drug during run-in and run-in duration did not affect the estimates in a consistent way.

Conclusions

The use of run-in in trials might have led to overestimated efficacy and especially underestimated risks of side effects of antipsychotics compared with placebo for NPS in dementia.

SUBMITTER: Hulshof TA

PROVIDER: S-EPMC7027584 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Publications

Run-in periods and clinical outcomes of antipsychotics in dementia: A meta-epidemiological study of placebo-controlled trials.

Hulshof Tessa A TA Zuidema Sytse U SU Gispen-de Wied Christine C CC Luijendijk Hendrika J HJ

Pharmacoepidemiology and drug safety 20191115 2

<h4>Purpose</h4>Run-in periods are used to identify placebo-responders and washout. Our aim was to assess the association of run-in periods with clinical outcomes of antipsychotics in dementia.<h4>Methods</h4>We searched randomized placebo-controlled trials of conventional and atypical antipsychotics for neuropsychiatric symptoms (NPS) in dementia in electronic sources and references of selected articles. We extracted (a) the presence of a run-in period, use of placebo/investigated drug during r ...[more]

PMID: 31730266

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Project description:ImportanceSingle-blind placebo run-in (PRI) periods are common in randomized clinical trials (RCTs) of treatment for depression. They aim to increase sensitivity to detect drug effects; however, the association of PRI periods with study outcomes remains unclear. This is concerning given the costs of PRI periods to patients and investigators.ObjectiveTo examine the association of the use of PRI periods with the placebo response, drug response, and drug-placebo difference among RCTs of antidepressants.Data sourcesMEDLINE, Embase, the Cochrane Central Register of Controlled Trials, and PsycINFO, as well as repositories of unpublished studies, were systematically searched up to July 2021.Study selectionIncluded studies were double-blind, placebo-controlled RCTs of antidepressant medication among adults with depressive disorders.Data extraction and synthesisData were extracted into a coding sheet, including the characteristics of studies, the characteristics of PRI periods, and the outcomes of studies.Main outcomes and measuresStudy outcomes were the primary depression symptom measure reported by the RCT. These outcomes were used to calculate effect sizes (Hedges g) of the within-group drug response and placebo response as well as the drug-placebo difference. Random-effects meta-analysis was used to calculate effect sizes, and subgroup analyses were used to compare outcomes depending on use of PRI periods.ResultsA total of 347 trials (representing 89 183 participants) were included; 174 studies (50%) reported using a single-blind PRI period. Response outcome data were available for 189 studies. Studies using PRI periods reported a smaller placebo response (g = 1.05 [95% CI, 0.98-1.11]; I2 = 82%) than studies that did not use a PRI period (g = 1.15 [95% CI, 1.09-1.21]; I2 = 81%; P = .02). Subgroup analysis showed a larger drug response size among studies that did not use a PRI period (g = 1.55 [95% CI, 1.49-1.61]; I2 = 85%) than those that did use a PRI period (g = 1.42 [95% CI, 1.36-1.48]; I2 = 81%; P = .001). The drug-placebo difference did not differ by use of PRI periods (g = 0.33 [95% CI, 0.29-0.38]; I2 = 47% for use of a PRI period vs g = 0.34 [95% CI, 0.30-0.38]; I2 = 54% for no use of PRI periods; P = .92). The likelihood of response to drug vs placebo also did not differ between studies that used a PRI period (odds ratio, 1.89 [95% CI, 1.76-2.03]) and those that did not use a PRI period (odds ratio, 1.77 [95% CI, 1.65-1.89]; P = .18).Conclusions and relevanceThis study suggests that RCTs using PRI periods yield smaller within-group changes across both placebo and drug groups compared with RCTs without PRI periods. The reduction in effect size across groups was equivalent in magnitude. Consequently, PRI studies do not observe larger drug-placebo differences, suggesting that they do not increase trial sensitivity. As such, given the resources and probable deception required and risk to external validity, the practice of using PRI periods in RCTs of antidepressants should be ended.

Project description:BackgroundAntipsychotics improve the positive symptoms of schizophrenia. However, little is known about the extent of antidepressive effects of antipsychotics and their correlation with effects on other symptom domains in schizophrenia. The aim was to investigate whether antidepressive effects of antipsychotics have a significant correlation with the effects on specific symptom domains of schizophrenia.MethodsElectronic databases were searched to identify eligible studies that reported antidepressive effects of antipsychotics for the treatment of adult patients with schizophrenia in double-blind, randomized placebo-controlled trials (RCTs). Mean change from baseline in depressive symptoms was meta-analyzed, and the correlation with the effects on other symptom domains was examined through meta-regression analysis.ResultsThirty-five RCTs (13 890 patients) were included in this meta-analysis. Overall, antipsychotics showed greater efficacy than placebo in reducing depressive symptoms, with small to medium effect sizes (standardized mean difference = -0.27, 95% confidence interval -0.32 to -0.22, P < .001). All the antipsychotics, except for chlorpromazine, haloperidol, and ziprasidone, were associated with significantly greater decreases in depressive symptoms compared with placebo (standardized mean difference = -0.19 to -0.40). A higher antidepressive effect was significantly correlated with a higher improvement in Positive and Negative Syndrome Scale/Brief Psychiatric Rating Scale total, positive, and negative, and Positive and Negative Syndrome Scale-general psychopathology symptoms (β = .618, P < .001; β = .476, P < .001; β = .689, P < .001; β = .603, P < .001, respectively).ConclusionsSecond-generation antipsychotics (except for ziprasidone) were associated with small to medium effects sizes on improvement in depressive symptoms among adult patients with schizophrenia. The antidepressive effect of antipsychotics was significantly correlated with improvement in other symptom domains, with the highest correlation observed for improvement in negative symptoms.Prospero registration numberCRD42019133015.

Project description:BackgroundChronic painful conditions have an important influence on the ability to work. Work-related outcomes, however, are not commonly reported in publications on trials investigating the treatment of chronic painful conditions. We aim to provide an overview of the reporting of work-related outcomes in such trials and investigate the relationship between work-related outcomes and pain outcomes.MethodsWe conducted a systematic literature search in PubMed with the aim of identifying randomised placebo-controlled clinical trials investigating treatments for chronic painful conditions or rheumatic diseases that also reported on work-related outcomes. Methodological study quality was assessed with the Oxford Quality Scale (OQS). Meta-analyses were conducted for the outcomes of interference with work and number of patients with at least 30% reduction in pain intensity (30% pain responders). The correlation between work-related and pain outcomes was investigated with regression analyses.ResultsWe included 31 publications reporting on 27 datasets from randomised placebo-controlled trials (with a total of 11,434 study participants) conducted in chronic painful or rheumatic diseases and reporting on work-related outcomes. These 31 publications make up only about 0.2% of all publications on randomised placebo-controlled trials in such conditions. The methodological quality of the included studies was high; only nine studies scored less than four (out of a maximum five) points on the OQS. Sixteen different work-related outcomes were reported on in the studies. Of 25 studies testing for the statistical significance of changes in work-related outcomes over the course of the trials, 14 (56%) reported a significant improvement; the others reported non-significant changes. Eight studies reported data on both interference with work and 30% pain responders: meta-analyses demonstrated similar, statistically significant improvements in both these outcomes with active therapy compared to placebo and regression analysis showed that these outcomes were correlated.ConclusionsDespite the importance of pain as a reason for decreased ability to work, work-related outcomes are reported in substantially less than 1% of publications on placebo-controlled trials in chronic painful and rheumatic diseases. Work-related outcomes and pain responder outcomes are closely related.

Project description:BackgroundEarly identification of participants at risk of run-in failure (RIF) may present opportunities to improve trial efficiency and generalizability.MethodsWe conducted a partial factorial-design, randomized, controlled trial of calcium and vitamin D to prevent colorectal adenoma recurrence at 11 centers in the United States. At baseline, participants completed two self-administered questionnaires (SAQs) and a questionnaire administered by staff. Participants in the full factorial randomization (calcium, vitamin D, both, or neither) received a placebo during a 3-month single-blinded run-in; women electing to take calcium enrolled in a two-group randomization (calcium with vitamin D, or calcium alone) and received calcium during the run-in. Using logistic regression models, we examined baseline factors associated with RIF in three subgroups: men (N = 1606) and women (N = 301) in the full factorial randomization and women in the two-group randomization (N = 666).ResultsOverall, 314/2573 (12 %) participants failed run-in; 211 (67 %) took fewer than 80 % of their tablets (poor adherence), and 103 (33 %) withdrew or were uncooperative. In multivariable models, 8- to 13-fold variation was seen by study center in odds of RIF risk in the two largest groups. In men, RIF decreased with age (adjusted odds ratio [OR] per 5 years 0.85 [95 % confidence interval, CI; 0.76-0.96]) and was associated with being single (OR 1.65 [95 % CI; 1.10-2.47]), not graduating from high school (OR 2.77 [95 % CI; 1.58-4.85]), and missing SAQ data (OR 1.97 [1.40-2.76]). Among women, RIF was associated primarily with health-related factors; RIF risk was lower with higher physical health score (OR 0.73 [95 % CI; 0.62-0.86]) and baseline multivitamin use (OR 0.44 [95 % CI; 0.26-0.75]). Women in the 5-year colonoscopy surveillance interval were at greater risk of RIF than those with 3-year follow-up (OR 1.91 [95 % CI; 1.08-3.37]), and the number of prescription medicines taken was also positively correlated with RIF (p = 0.03). Perceived toxicities during run-in were associated with 12- to 29-fold significantly increased odds of RIF.ConclusionsThere were few common baseline predictors of run-in failure in the three randomization groups. However, heterogeneity in run-in failure associated with study center, and missing SAQ data reflect potential opportunities for intervention to improve trial efficiency and retention.Trial registrationClinicalTrials.gov: NCT00153816 . Registered September 2005.

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Project description:ObjectiveTo quantify and compare the treatment effect and risk of bias of trials reporting biomarkers or intermediate outcomes (surrogate outcomes) versus trials using final patient relevant primary outcomes.DesignMeta-epidemiological study.Data sourcesAll randomised clinical trials published in 2005 and 2006 in six high impact medical journals: Annals of Internal Medicine, BMJ, Journal of the American Medical Association, Lancet, New England Journal of Medicine, and PLoS Medicine.Study selectionTwo independent reviewers selected trials.Data extractionTrial characteristics, risk of bias, and outcomes were recorded according to a predefined form. Two reviewers independently checked data extraction. The ratio of odds ratios was used to quantify the degree of difference in treatment effects between the trials using surrogate outcomes and those using patient relevant outcomes, also adjusted for trial characteristics. A ratio of odds ratios >1.0 implies that trials with surrogate outcomes report larger intervention effects than trials with patient relevant outcomes.Results84 trials using surrogate outcomes and 101 using patient relevant outcomes were considered for analyses. Study characteristics of trials using surrogate outcomes and those using patient relevant outcomes were well balanced, except for median sample size (371 v 741) and single centre status (23% v 9%). Their risk of bias did not differ. Primary analysis showed trials reporting surrogate endpoints to have larger treatment effects (odds ratio 0.51, 95% confidence interval 0.42 to 0.60) than trials reporting patient relevant outcomes (0.76, 0.70 to 0.82), with an unadjusted ratio of odds ratios of 1.47 (1.07 to 2.01) and adjusted ratio of odds ratios of 1.46 (1.05 to 2.04). This result was consistent across sensitivity and secondary analyses.ConclusionsTrials reporting surrogate primary outcomes are more likely to report larger treatment effects than trials reporting final patient relevant primary outcomes. This finding was not explained by differences in the risk of bias or characteristics of the two groups of trials.

Dataset Information

Run-in periods and clinical outcomes of antipsychotics in dementia: A meta-epidemiological study of placebo-controlled trials.

Purpose

Methods

Results

Conclusions

Publications

Run-in periods and clinical outcomes of antipsychotics in dementia: A meta-epidemiological study of placebo-controlled trials.

Similar Datasets

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