A cumulative meta-analysis of selective serotonin reuptake inhibitors in pediatric depression: did unpublished studies influence the efficacy/safety debate?

Annual Research Review: Defining and treating pediatric treatment-resistant depression

BACKGROUND

Adolescent major depressive disorder (MDD) is a significant health problem, associated with substantial morbidity, cost, and mortality. Depression is a significant risk factor for suicide, which is now the second leading cause of death in young people. Up to twenty per cent of adolescents will experience MDD before adulthood, and while a substantial proportion will improve with standard-of-care treatments (psychotherapy and medication), roughly one third will not.

METHODS

Here, we have reviewed the literature in order to discuss the concept of treatment-resistant depression (TRD) in adolescence, examine risk factors, diagnostic difficulties, and challenges in evaluating symptom improvement, and providing guidance on how to define adequate medication and psychotherapy treatment trials.

RESULTS

We propose a staging model for adolescent TRD and review the treatment literature. The evidence base for first- and second-line treatments primarily derives from four large pediatric clinical trials (TADS, TORDIA, ADAPT, and IMPACT). After two medications and a trial of evidence-based psychotherapy have failed to alleviate depressive symptoms, the evidence becomes quite thin for subsequent treatments. Here, we review the evidence for the effectiveness of medication switches, medication augmentation, psychotherapy augmentation, and interventional treatments (i.e., transcranial magnetic stimulation, electroconvulsive therapy, and ketamine) for adolescent TRD. Comparisons are drawn to the adult TRD literature, and areas for future pediatric depression research are highlighted.

CONCLUSIONS

As evidence is limited for treatments in this population, a careful consideration of the known risks and side effects of escalated treatments (e.g., mood stabilizers and atypical antipsychotics) is warranted and weighed against potential, but often untested, benefits.

Crowdsourcing the Citation Screening Process for Systematic Reviews: Validation Study

BACKGROUND

Systematic reviews (SRs) are often cited as the highest level of evidence available as they involve the identification and synthesis of published studies on a topic. Unfortunately, it is increasingly challenging for small teams to complete SR procedures in a reasonable time period, given the exponential rise in the volume of primary literature. Crowdsourcing has been postulated as a potential solution.

OBJECTIVE

The feasibility objective of this study was to determine whether a crowd would be willing to perform and complete abstract and full text screening. The validation objective was to assess the quality of the crowd's work, including retention of eligible citations (sensitivity) and work performed for the investigative team, defined as the percentage of citations excluded by the crowd.

METHODS

We performed a prospective study evaluating crowdsourcing essential components of an SR, including abstract screening, document retrieval, and full text assessment. Using CrowdScreenSR citation screening software, 2323 articles from 6 SRs were available to an online crowd. Citations excluded by less than or equal to 75% of the crowd were moved forward for full text assessment. For the validation component, performance of the crowd was compared with citation review through the accepted, gold standard, trained expert approach.

RESULTS

Of 312 potential crowd members, 117 (37.5%) commenced abstract screening and 71 (22.8%) completed the minimum requirement of 50 citation assessments. The majority of participants were undergraduate or medical students (192/312, 61.5%). The crowd screened 16,988 abstracts (median: 8 per citation; interquartile range [IQR] 7-8), and all citations achieved the minimum of 4 assessments after a median of 42 days (IQR 26-67). Crowd members retrieved 83.5% (774/927) of the articles that progressed to the full text phase. A total of 7604 full text assessments were completed (median: 7 per citation; IQR 3-11). Citations from all but 1 review achieved the minimum of 4 assessments after a median of 36 days (IQR 24-70), with 1 review remaining incomplete after 3 months. When complete crowd member agreement at both levels was required for exclusion, sensitivity was 100% (95% CI 97.9-100) and work performed was calculated at 68.3% (95% CI 66.4-70.1). Using the predefined alternative 75% exclusion threshold, sensitivity remained 100% and work performed increased to 72.9% (95% CI 71.0-74.6; P<.001). Finally, when a simple majority threshold was considered, sensitivity decreased marginally to 98.9% (95% CI 96.0-99.7; P=.25) and work performed increased substantially to 80.4% (95% CI 78.7-82.0; P<.001).

CONCLUSIONS

Crowdsourcing of citation screening for SRs is feasible and has reasonable sensitivity and specificity. By expediting the screening process, crowdsourcing could permit the investigative team to focus on more complex SR tasks. Future directions should focus on developing a user-friendly online platform that allows research teams to crowdsource their reviews.

Reporting of Adverse Events in Published and Unpublished Studies of Health Care Interventions: A Systematic Review

BACKGROUND

We performed a systematic review to assess whether we can quantify the underreporting of adverse events (AEs) in the published medical literature documenting the results of clinical trials as compared with other nonpublished sources, and whether we can measure the impact this underreporting has on systematic reviews of adverse events.

METHODS AND FINDINGS

Studies were identified from 15 databases (including MEDLINE and Embase) and by handsearching, reference checking, internet searches, and contacting experts. The last database searches were conducted in July 2016. There were 28 methodological evaluations that met the inclusion criteria. Of these, 9 studies compared the proportion of trials reporting adverse events by publication status. The median percentage of published documents with adverse events information was 46% compared to 95% in the corresponding unpublished documents. There was a similar pattern with unmatched studies, for which 43% of published studies contained adverse events information compared to 83% of unpublished studies. A total of 11 studies compared the numbers of adverse events in matched published and unpublished documents. The percentage of adverse events that would have been missed had each analysis relied only on the published versions varied between 43% and 100%, with a median of 64%. Within these 11 studies, 24 comparisons of named adverse events such as death, suicide, or respiratory adverse events were undertaken. In 18 of the 24 comparisons, the number of named adverse events was higher in unpublished than published documents. Additionally, 2 other studies demonstrated that there are substantially more types of adverse events reported in matched unpublished than published documents. There were 20 meta-analyses that reported the odds ratios (ORs) and/or risk ratios (RRs) for adverse events with and without unpublished data. Inclusion of unpublished data increased the precision of the pooled estimates (narrower 95% confidence intervals) in 15 of the 20 pooled analyses, but did not markedly change the direction or statistical significance of the risk in most cases. The main limitations of this review are that the included case examples represent only a small number amongst thousands of meta-analyses of harms and that the included studies may suffer from publication bias, whereby substantial differences between published and unpublished data are more likely to be published.

CONCLUSIONS

There is strong evidence that much of the information on adverse events remains unpublished and that the number and range of adverse events is higher in unpublished than in published versions of the same study. The inclusion of unpublished data can also reduce the imprecision of pooled effect estimates during meta-analysis of adverse events.

Systematic Review and Meta-Analysis: Early Treatment Responses of Selective Serotonin Reuptake Inhibitors in Pediatric Major Depressive Disorder

OBJECTIVE

Selective serotonin reuptake inhibitors (SSRIs) are the first-line pharmacological treatment for pediatric major depressive disorder (MDD). We conducted a meta-analysis to examine the following: the time-course of response to SSRIs in pediatric depression; whether higher doses of SSRIs are associated with an improved response in pediatric depression; differences in efficacy between SSRI agents; and whether the time-course and magnitude of response to SSRIs is different in pediatric and adult patients with MDD.

METHOD

We searched PubMed and CENTRAL for randomized controlled trials comparing SSRIs to placebo for the treatment of pediatric MDD. We extracted weekly symptom data from trials to characterize the trajectory of pharmacological response to SSRIs. Pooled estimates of treatment effect were calculated based on standardized mean differences between treatment and placebo groups.

RESULTS

The meta-analysis included 13 pediatric MDD trials with a total of 3,004 patients. A logarithmic model indicating that the greatest benefits of SSRIs occurred early in treatment best fit the longitudinal data (log[week] = 0.10, 95% CI = 0.06-0.15, p < .0001). There were no significant differences based on maximum SSRI dose or between particular SSRI agents. SSRIs were demonstrated to have a smaller benefit in pediatric compared to adult MDD.

CONCLUSION

Treatment gains in pediatric MDD are greatest early in treatment and are, on average, minimal after 4 weeks of SSRI pharmacotherapy in pediatric MDD. Further research is needed using individual patient data to examine the power of early SSRI response (e.g., 2-4 weeks) to predict outcomes in short-term pharmacological trials.

Accumulating research: a systematic account of how cumulative meta-analyses would have provided knowledge, improved health, reduced harm and saved resources

Background

“Cumulative meta-analysis” describes a statistical procedure to calculate, retrospectively, summary estimates from the results of similar trials every time the results of a further trial in the series had become available. In the early 1990s, comparisons of cumulative meta-analyses of treatments for myocardial infarction with advice promulgated through medical textbooks showed that research had continued long after robust estimates of treatment effects had accumulated, and that medical textbooks had overlooked strong, existing evidence from trials. Cumulative meta-analyses have subsequently been used to assess what could have been known had new studies been informed by systematic reviews of relevant existing evidence and how waste might have been reduced.

Methods and Findings

We used a systematic approach to identify and summarise the findings of cumulative meta-analyses of studies of the effects of clinical interventions, published from 1992 to 2012. Searches were done of PubMed, MEDLINE, EMBASE, the Cochrane Methodology Register and Science Citation Index. A total of 50 eligible reports were identified, including more than 1,500 cumulative meta-analyses. A variety of themes are illustrated with specific examples. The studies showed that initially positive results became null or negative in meta-analyses as more trials were done; that early null or negative results were over-turned; that stable results (beneficial, harmful and neutral) would have been seen had a meta-analysis been done before the new trial; and that additional trials had been much too small to resolve the remaining uncertainties.

Conclusions

This large, unique collection of cumulative meta-analyses highlights how a review of the existing evidence might have helped researchers, practitioners, patients and funders make more informed decisions and choices about new trials over decades of research. This would have led to earlier uptake of effective interventions in practice, less exposure of trial participants to less effective treatments, and reduced waste resulting from unjustified research.

Excessive mood elevation and behavioral activation with antidepressant treatment of juvenile depressive and anxiety disorders: a systematic review

BACKGROUND

The prevalence, characteristics and implications of excessive arousal-activation in children and adolescents treated with antidepressants for specific illnesses have not been systematically examined.

METHODS

We compared reports of antidepressant trials (n = 6,767 subjects) in juvenile depressive (n = 17) and anxiety disorders (n = 25) for consensus-based indications of psychopathological mood elevation or behavioral activation.

RESULTS

Rates of excessive arousal-activation during treatment with antidepressants were at least as high in juvenile anxiety (13.8%) as depressive (9.79%) disorders, and much lower with placebos (5.22 vs. 1.10%, respectively; both p < 0.0001). The antidepressant/placebo risk ratio for such reactions in paired comparisons was 3.50 (12.9/3.69%), and the meta-analytically pooled rate ratio was 1.7 (95% confidence interval: 1.2-2.2; both p ≤ 0.001). Overall rates for 'mania or hypomania', specifically, were 8.19% with and 0.17% without antidepressant treatment, with large drug/placebo risk ratios among depressive (10.4/0.45%) and anxiety (1.98/0.00%) disorder patients.

CONCLUSIONS

Risks of excessive mood elevation during antidepressant treatment, including mania-hypomania, were much greater than with placebo, and similar in juvenile anxiety and depressive disorders. Excessive arousal-activation in children or adolescents treated with antidepressants for anxiety as well as depressive disorders calls for particular caution and monitoring for potential risk of future bipolar disorder.

Psychopharmacology for medically ill adolescents

Medically ill adolescents are at increased risk for psychological distress and/or functional impairment. However, there are few research studies examining the optimal psychiatric treatments for this population. Psychiatric medication recommendations are largely based on studies of youth with a primary psychiatric disorder, adult studies, hypothesized mechanisms of action, and/or clinical experience. This paper provides evidence-informed recommendations for the psychopharmacological treatment of acutely medically ill adolescents suffering from significant psychological distress and/or functional impairment. Representing the most common problems among medically ill adolescents that are treated with psychiatric medications, recommendations are provided for anxiety and depression; iatrogenic medical trauma, inadequate sleep and insomnia; and, delirium.

Evidence map of prevention and treatment interventions for depression in young people

Introduction. Depression in adolescents and young people is associated with reduced social, occupational, and interpersonal functioning, increases in suicide and self-harm behaviours, and problematic substance use. Age-appropriate, evidence-based treatments are required to provide optimal care. Methods. "Evidence mapping" methodology was used to quantify the nature and distribution of the extant high-quality research into the prevention and treatment of depression in young people across psychological, medical, and other treatment domains. Results. Prevention research is dominated by cognitive-behavioral- (CBT-) based interventions. Treatment studies predominantly consist of CBT and SSRI medication trials, with few trials of other psychological interventions or complementary/alternative treatments. Quality studies on relapse prevention and treatment for persistent depression are distinctly lacking. Conclusions. This map demonstrates opportunities for future research to address the numerous evidence gaps for interventions to prevent or treat depression in young people, which are of interest to clinical researchers, policy makers, and funding bodies.

Unpublished data can be of value in systematic reviews of adverse effects: methodological overview

OBJECTIVE

To assess the impact of including unpublished data on adverse effects in systematic reviews.

STUDY DESIGN AND SETTING

We carried out a systematic review of methodological evaluations that compared the quantitative reporting of adverse effects data between published and unpublished sources, in particular, the frequency, rate, or risk of reported adverse effects. Included studies were sought from 10 databases as well as by checking references, handsearching, searching citations, and contacting experts.

RESULTS

We identified 6,218 potential articles yielding 10 relevant methodological evaluations. One evaluation found that adverse effects were reported more often in unpublished trials. For anecdotal case reports, two evaluations found a higher frequency of unpublished cases, whereas one study identified a greater number of published cases. Another evaluation indicated that differences in frequency of published and unpublished case reports were topic dependent. A comparison of relative risk estimates from five studies suggested no major systematic variation in risk estimates from published and unpublished studies.

CONCLUSION

Inclusion of unpublished studies can provide additional adverse effects information and more precise risk estimates. However, there is insufficient evidence to indicate whether inclusion of unpublished studies has a major influence on the pooled risk estimates in meta-analyses of adverse effects.

Canadian Network for Mood and Anxiety Treatments (CANMAT) clinical guidelines for the management of major depressive disorder in adults. III. Pharmacotherapy

BACKGROUND

In 2001, the Canadian Psychiatric Association and the Canadian Network for Mood and Anxiety Treatments (CANMAT) partnered to produce evidence-based clinical guidelines for the treatment of depressive disorders. A revision of these guidelines was undertaken by CANMAT in 2008-2009 to reflect advances in the field.

METHODS

The CANMAT guidelines are based on a question-answer format to enhance accessibility to clinicians. An evidence-based format was used with updated systematic reviews of the literature and recommendations were graded according to Level of Evidence using pre-defined criteria. Lines of Treatment were identified based on criteria that included Levels of Evidence and expert clinical support. This section on "Pharmacotherapy" is one of 5 guideline articles.

RESULTS

Despite emerging data on efficacy and tolerability differences amongst newer antidepressants, variability in patient response precludes identification of specific first choice medications for all patients. All second-generation antidepressants have Level 1 evidence to support efficacy and tolerability and most are considered first-line treatments for MDD. First-generation tricyclic and monoamine oxidase inhibitor antidepressants are not the focus of these guidelines but generally are considered second- or third-line treatments. For inadequate or incomplete response, there is Level 1 evidence for switching strategies and for add-on strategies including lithium and atypical antipsychotics.

LIMITATIONS

Most of the evidence is based on trials for registration and may not reflect real-world effectiveness.

CONCLUSIONS

Second-generation antidepressants are safe, effective and well tolerated treatments for MDD in adults. Evidence-based switching and add-on strategies can be used to optimize response in MDD that is inadequately responsive to monotherapy.

[Antidepressant use in children and adolescents]

Relative to placebo, selective serotonin reuptake inhibitors (SSRI) are efficacious for paediatric affective disorders, although their clinical effects appear relatively modest in major depressive disorder, intermediate in obsessive-compulsive disorder, and stronger in anxiety disorders. If SSRIs modestly increase the risk of occurrence of suicidal ideation and behavior, several studies show that their use is associated with a significant decrease in the suicide rates in children and adolescents, probably because of their efficacy, compliance, and low toxicity in overdose.

Selection criteria and generalizability within the counterfactual framework: explaining the paradox of antidepressant-induced suicidality?

BACKGROUND

Although the superior internal validity of the randomized clinical trial (RCT) is invaluable to establish causality, generalizability is far from guaranteed. In particular, strict selection criteria intended to maximize treatment efficacy and safety can impair external validity. This problem is widely acknowledged in principle but sometimes ignored in practice, with considerable consequences for treatment options.

PURPOSE

We demonstrate how selection of patients for an RCT can bias the results when the treatment effect varies across individuals. Indeed, not only the magnitude, but even the direction of the causal effect found in an RCT can differ from the causal effect in the target population.

METHODS

A counterfactual model is developed to represent the selection process explicitly. This simple extension of the standard counterfactual model is used to explore the implications of restrictive exclusion criteria intended to eliminate high-risk individuals. The counterintuitive findings of a recent FDA meta-analysis of suicidality in pediatric populations treated with antidepressant medications are interpreted in the light of this counterfactual model.

RESULTS

When the causal effect of an intervention can vary across individuals, the potential for selection bias (in the sense of a threat to external validity) can be serious. In particular, we demonstrate that the stricter the inclusion/exclusion criteria the greater the potential inflation of relative risk. A critical factor in determining bias is the extent to which individuals with differing types of causal effects can be distinguished prior to sampling. Furthermore, we propose methods that can sometimes be useful to identify the existence of bias in an actual study. When applied to the FDA meta-analysis of pediatric suicidality in RCTs of modern antidepressant medications, these methods suggest that the elevated risk observed may be an artifact of selection bias.

LIMITATIONS

Real-life scenarios are generally more complex than the counterfactual model presented here. Future modeling efforts are needed to refine and extend our approach.

CONCLUSIONS

When variation of treatment effects across individuals is plausible, lack of generalizability should be a serious concern. Therefore, external validity of RCTs needs to be carefully considered in the design of an RCT and the interpretation of its results, especially when the study can influence regulatory decisions about drug safety. RCTs should not automatically be considered definitive, especially when their results conflict with those of observational studies. Whenever possible, empirical evidence of bias resulting from sample selection should be obtained and taken into account.

Screening for child and adolescent depression in primary care settings: a systematic evidence review for the US Preventive Services Task Force

CONTEXT

Depression among youth is a disabling condition that is associated with serious long-term morbidities and suicide.

OBJECTIVE

To assess the health effects of routine primary care screening for major depressive disorder among children and adolescents aged 7 to 18 years.

METHODS

Medline, the Cochrane Central Registry of Controlled Trials, PsycInfo, the Cochrane Database of Systematic Reviews, recent systematic reviews, experts, and bibliographies from selected studies were the data sources. The studies selected were fair- and good-quality (on the basis of US Preventive Services Task Force criteria) controlled trials of screening and treatment (selective serotonin reuptake inhibitor and/or psychotherapy), diagnostic accuracy studies, and large observational studies that reported adverse events. Two reviewers quality-graded each article. One reviewer abstracted relevant information into standardized evidence tables, and a second reviewer checked key elements.

RESULTS

We found no data describing health outcomes among screened and unscreened populations. Although the literature on diagnostic screening test accuracy is small and methodologically limited, it indicates that several screening instruments have performed fairly well among adolescents. The literature on treatment efficacy of selective serotonin reuptake inhibitors and/or psychotherapy is also small but includes good-quality randomized, controlled trials. Available data indicate that selective serotonin reuptake inhibitors, psychotherapy, and combined treatment are effective in increasing response rates and reducing depressive symptoms. Not all specific selective serotonin reuptake inhibitors, however, seem to be efficacious. Selective serotonin reuptake inhibitor treatment was associated with a small absolute increase in risk of suicidality (ie, suicidal ideation, preparatory acts, or attempts). No suicide deaths occurred in any of the trials. CONCLUSIONS. Limited available data suggest that primary care-feasible screening tools may accurately identify depressed adolescents and treatment can improve depression outcomes. Treating depressed youth with selective serotonin reuptake inhibitors may be associated with a small increased risk of suicidality and should only be considered if judicious clinical monitoring is possible.

[Efficacy of psychiatric and psychotherapeutic interventions in children and adolescents with psychiatric disorders--a systematic evaluation of meta-analyses and reviews. Part I: Anxiety disorders and depressive disorders]

OBJECTIVE

In recent years, a large and growing body of research on the effectiveness of treatments for psychiatric disorders in childhood and adolescence has been published; however, the large number makes it difficult to get an overview on the current status of research. The aim of this article is to systematically review the existing meta-analyses and reviews on the four most frequent childhood and adolescent psychiatric disorders (anxiety disorder, depression, ADHD, conduct disorder) and to present an up-to-date summary on the effects of treatment for those disorders.

METHODS

This article is based on a systematic literature search, which produced 112 meta-analyses and reviews on efficacy of psychological and psychiatric interventions in childhood and adolescence published between 2000 and 2007. The articles resulting from the literature search were evaluated according to clearly defined criteria. Presentation of the results follows a dichotomous classification (internalizing vs. externalizing disorders), with Part I of this article reporting the results on anxiety disorders and depressive disorders.

RESULTS

The majority of reviews published between 2000 and 2007 focuses on the treatment of depressive disorders and ADHD. Only for ADHD is the use of medication (stimulants) considered to be the most efficacious treatment option available. For the remaining three disorders, psychotherapy is recommended as the most effective treatment of choice. A combination of psychological and pharmacological treatments is an important option in ADHD and depressive disorders. Considering the efficacy, treatments for ADHD and anxiety disorders produce higher effect-sizes than do interventions for depressive and conduct disorders. For all disorders, there are several desiderata (content and methodological aspects) to be incorporated into future research.

DISCUSSION

Empirically supported treatment recommendations can be derived for anxiety disorders, depressive disorders, ADHD and conduct disorders. Finally, important implications for research and practice are discussed.

Randomised controlled trials of selective serotonin reuptake inhibitors in treating depression in children and adolescents: a systematic review and meta-analysis

To evaluate the efficacy of selective serotonin reuptake inhibitors (SSRIs) in children and adolescents with depressive disorder, the main electronic databases and the reference lists of retrieved articles and reviews were searched up to January 2007. Randomized controlled studies (RCT) were assessed for methodological quality, taking into consideration the specific diagnostic and severity evaluation tools used, and a meta-analysis on the efficacy of SSRIs compared placebo was undertaken. In all, 13 studies were included, covering a total of 2530 children and adolescents. Eleven studies met the criteria for inclusion in the meta-analysis. The pooled odds ratio was 1.57 (95% C.I. 1.29-1.91). Only fluoxetine appeared to offer a moderately significant benefit profile (OR=2.39). All studies differed in diagnostic tools and primary efficacy measures. SSRI treatment, especially with fluoxetine, may be effective on child and adolescent depression. Nevertheless, additional RCTs with sound methodological designs, validated diagnostic instruments, large sample sizes, and consistent outcomes are necessary to determine the role of SSRIs, alone or in combination with psychological interventions in the treatment of depression in children and adolescents.

Drug Treatment in Juvenile Depression - Is St. John's Wort a Safe and Effective Alternative?

Analyses of juvenile depression studies with long established anti-depressants (tricyclic anti-depressants) have revealed discouragingly little benefit, while side effects have been profound. Modern anti-depressants like selective serotonin reuptake inhibitors seemed to solve part of this problem until they were found to be associated with an increased risk of suicidal attempts and ideation, hostile behaviour and self-harm, while meta-analyses have revealed only marginal therapeutic effects for the majority. Actually, no drug is unequivocally accepted as the gold-standard for young depressive patients. St. John's Wort (SJW) has been traditionally used in Europe to treat symptoms associated with juvenile depression. Close to 50 clinical studies performed over the last two decades have been presented as evidence that standardized SJW preparations are equally effective as synthetic anti-depressants in the treatment of mild to moderate depression in adults. Tolerability is excellent, but some relevant drug interactions have to be considered. Today, SJW is by far the most frequently prescribed medication for child and adolescent depression in Germany. Some pilot and observational studies from Germany, Canada and the US have delivered promising results. However, randomised controlled trials amongst this age group have yet to be carried out and are long overdue.