Do children and adolescents have differential response rates in placebo-controlled trials of fluoxetine?

Evidence for machine learning guided early prediction of acute outcomes in the treatment of depressed children and adolescents with antidepressants

BACKGROUND

The treatment of depression in children and adolescents is a substantial public health challenge. This study examined artificial intelligence tools for the prediction of early outcomes in depressed children and adolescents treated with fluoxetine, duloxetine, or placebo.

METHODS

The study samples included training datasets (N = 271) from patients with major depressive disorder (MDD) treated with fluoxetine and testing datasets from patients with MDD treated with duloxetine (N = 255) or placebo (N = 265). Treatment trajectories were generated using probabilistic graphical models (PGMs). Unsupervised machine learning identified specific depressive symptom profiles and related thresholds of improvement during acute treatment.

RESULTS

Variation in six depressive symptoms (difficulty having fun, social withdrawal, excessive fatigue, irritability, low self-esteem, and depressed feelings) assessed with the Children's Depression Rating Scale-Revised at 4-6 weeks predicted treatment outcomes with fluoxetine at 10-12 weeks with an average accuracy of 73% in the training dataset. The same six symptoms predicted 10-12 week outcomes at 4-6 weeks in (a) duloxetine testing datasets with an average accuracy of 76% and (b) placebo-treated patients with accuracies of 67%. In placebo-treated patients, the accuracies of predicting response and remission were similar to antidepressants. Accuracies for predicting nonresponse to placebo treatment were significantly lower than antidepressants.

CONCLUSIONS

PGMs provided clinically meaningful predictions in samples of depressed children and adolescents treated with fluoxetine or duloxetine. Future work should augment PGMs with biological data for refined predictions to guide the selection of pharmacological and psychotherapeutic treatment in children and adolescents with depression.

Restoring the two pivotal fluoxetine trials in children and adolescents with depression

BACKGROUND

Fluoxetine was approved for depression in children and adolescents based on two placebo-controlled trials, X065 and HCJE, with 96 and 219 participants, respectively.

OBJECTIVE

To review these trials, which appear to have been misreported.

METHODS

Systematic review of the clinical study reports and publications. The primary outcomes were the efficacy variables in the trial protocols, suicidal events, and precursors to suicidality or violence.

RESULTS

Essential information was missing and there were unexplained numerical inconsistencies. (1) The efficacy outcomes were biased in favour of fluoxetine by differential dropouts and missing data. The efficacy on the Children's Depression Rating Scale-Revised was 4% of the baseline score, which is not clinically relevant. Patient ratings did not find fluoxetine effective. (2) Suicidal events were missing in the publications and the study reports. Precursors to suicidality or violence occurred more often on fluoxetine than on placebo. For trial HCJE, the number needed to harm was 6 for nervous system events, 7 for moderate or severe harm, and 10 for severe harm. Fluoxetine reduced height and weight over 19 weeks by 1.0 cm and 1.1 kg, respectively, and prolonged the QT interval.

CONCLUSIONS

Our reanalysis of the two pivotal trials showed that fluoxetine is unsafe and ineffective.

Meta-Analysis: Pediatric Placebo Response in Depression Trials Does Not Replicate in Anxiety and Obsessive-Compulsive Disorder Trials

Background: Placebo response has been identified as an important factor influencing the success of adult antidepressant trials, yet little research of placebo response has been conducted in pediatric populations. Understanding disorder-specific and transdiagnostic predictors of pediatric placebo response is important in designing successful child psychopharmacological trials. Methods: A PubMed search was conducted for all pediatric antidepressant randomized controlled trials treating depression, anxiety, or obsessive-compulsive disorder (OCD). A random-effects model was utilized to examine the magnitude of placebo symptom improvement using standardized mean difference (SMD) and placebo response rates. Stratified subgroup analysis was performed by diagnostic indication. Meta-regression was utilized to search possible correlates of placebo symptom improvement and placebo response rate. Results: Thirty antidepressant trials involving 2911 participants receiving placebo were included in this meta-analysis. Magnitude of placebo improvement and placebo response rates varied significantly across disorders; being greater in depression (SMD = 1.44, 95% confidence interval [CI]: 1.18 to 1.71) than anxiety disorders (SMD = 1.09, 95% CI: 0.77 to 1.41) and the lowest in OCD (SMD = 0.71, 95% CI: 0.32 to 1.12). Different predictors were associated with placebo response in different indications. Conclusions: Both the magnitude and predictors of placebo response in pediatric depression trials do not replicate across anxiety and OCD. Based on our results, across disorders, minimizing the number of sites might significantly reduce placebo improvement. In addition to these, we could potentially decrease the placebo response in depression trials by increasing the number of subjects enrolled per study site, minimizing the number of study visits and conducting the studies in the United States. Further research is needed into the predictors of placebo response in pediatric anxiety and OCD.

Anticipatory Effects on Perceived Pain: Associations With Development and Anxiety

OBJECTIVE

Naturalistic studies suggest that expectation of adverse experiences such as pain exerts particularly strong effects on anxious youth. In healthy adults, expectation influences the experience of pain. The current study uses experimental methods to compare the effects of expectation on pain among adults, healthy youth, and youth with an anxiety disorder.

METHODS

Twenty-three healthy adults, 20 healthy youth, and 20 youth with an anxiety disorder underwent procedures in which auditory cues were paired with noxious thermal stimulation. Through instructed conditioning, one cue predicted low-pain stimulation and the other predicted high-pain stimulation. At test, each cue was additionally followed by a single temperature calibrated to elicit medium pain ratings. We compared cue-based expectancy effects on pain across the three groups, based on cue effects on pain elicited on medium heat trials.

RESULTS

Across all groups, as expected, participants reported greater pain with increasing heat intensity (β = 2.29, t(41) = 29.94, p < .001). Across all groups, the critical medium temperature trials were rated as more painful in the high- relative to low-expectancy condition (β = 1.72, t(41) = 10.48, p < .001). However, no evidence of between-group differences or continuous associations with age or anxiety was observed.

CONCLUSIONS

All participants showed strong effects of expectancy on pain. No influences of development or anxiety arose. Complex factors may influence associations among anxiety, development, and pain reports in naturalistic studies. Such factors may be identified using experiments that employ more complex, yet controlled manipulations of expectancy or assess neural correlates of expectancy.

Pharmacotherapy of adolescent depression - fluoxetine monotherapy or combined treatment?

Depressive disorder is one of the most common and serious psychiatric diagnosis in paediatric population, often connected with suicidal risk. In recent years, fluoxetine monotherapy is the gold standard in acute phase of depression treatment in children and adolescents, but is not effective enough after an acute phase of treatment. More helpful researches concerning more effective therapeutic strategies of depression in this age are insufficient. The aim of our study is to evaluate the effectiveness and safety of fluoxetine monotherapy in comparison with combined olanzapine/fluoxetine therapy in acute 6-week treatment of depression in adolescence. We found that combined therapeutic strategy, using olanzapine augmentation is predicted to be more useful in the treatment of adolescent depression.

Understanding the Impact of Treatment on the Dimensions of Childhood Depression

BACKGROUND

Childhood depression is often chronic and recurrent, with only modest improvements after optimal treatments. Novel approaches are needed for accurate diagnosis, timely selection of the best treatment for childhood depression, and improvement of remission rates. An important part of diagnosis is to determine how many consistent dimensions underlie childhood depression and what impact treatment may have on these dimensions.

OBJECTIVE

The goal of the current study is evaluate the consistency of the number of depressive symptom dimensions and examine the effect of depression treatment on the change in dimensions by seeing if this dimensional structure is the same for groups that were given a placebo and groups that were given an active drug, fluoxetine.

METHODS

We examined a combined sample of three clinical trials data sets with a total of 269 placebo patients and 261 fluoxetine patients at baseline, and 253 placebo patients and 249 fluoxetine patients at exit. Principal components analysis with associated parallel analysis followed by a ProMax oblique rotation was conducted on each week's scores. The similarity of the rotated structures between treatments and between weeks was then assessed using Wrigley and Neuhaus' (1955) degree of factorial similarity measure, which is a correlation-like statistic that takes two solutions based upon the same measures and assesses how similar they are.

RESULTS

Preliminary analysis indicated that mean scores of both treatment groups declined from baseline to exit, but the decline was greater for the fluoxetine group. There were four dimensions at baseline and two dimensions at exit in each treatment group. Hence the numbers of dimensions were the same in the two groups, whereas the content of the components was the same at baseline for the two groups, but was different at exit. Basically, the factorial similarities of the rotated factors were very high at baseline between the two groups for both factors (Ψ = 0.97 for factor I and 0.94 for factor II) before they were treated differently. However, at exit, the respective similarities dropped to 0.58 and -0.04 for factors I and II. Therefore, time had a large effect in changing both groups' factor structure, but it was especially large when there was an active treatment.

CONCLUSIONS

In comparing the baseline and exit dimensions in a forced two factor solution of two treatment groups, it was revealed that treatment did have an impact on the change in dimensions. These results further the generality of the simplification of the factor structure of the Childhood Depression Rating Scale- Revised (CDRS-R) over time. In addition, these results show the effect of time and therapy on the factor structures. The fluoxetine group followed the trend of the content of the dimensions revealed in a previous study, whereas the placebo group had a less distinct change over time.

Comparative efficacy and tolerability of pharmacological interventions for attention-deficit/hyperactivity disorder in children, adolescents and adults: protocol for a systematic review and network meta-analysis

INTRODUCTION

Attention-deficit/hyperactivity disorder (ADHD) is a major public health issue. Pharmacological treatments play an important role in the multimodal treatment of ADHD. Currently, there is a lack of up-to-date and comprehensive evidence on how available ADHD drugs compare and rank in terms of efficacy and tolerability, in children or adolescents as well as in adults. We will conduct a network meta-analysis (NMA), integrating direct and indirect comparisons from randomised controlled trials (RCTs), to rank pharmacological treatments for ADHD according to their efficacy and tolerability profiles.

METHODS AND ANALYSIS

We will search a broad range of electronic databases, including PubMed, MEDLINE, EMBASE, PsycINFO, ERIC and Web of Science, with no date or language restrictions. We will also search for unpublished studies using international clinical trial registries and contacting relevant drug companies. We will identify and include available parallel-group, cross-over and cluster randomised trials that compare methylphenidate, dexmethylphenidate, amphetamine derivatives (including lisdexamfetamine), atomoxetine, clonidine, guanfacine, bupropion or modafinil (as oral therapy) either with each other or to placebo, in children, adolescents or adults with ADHD. Primary outcomes will be efficacy (indicated by reduction in severity of ADHD core symptoms measured on a standardised scale) and tolerability (the proportion of patients who left a study early due to side effects). Secondary outcomes will be global functioning, acceptability (proportion of patients who left the study early by any cause) and changes in blood pressure and body weight. NMA will be conducted in STATA within a frequentist framework. The quality of RCTs will be evaluated using the Cochrane risk of bias tool, and the quality of the evidence will be assessed using the GRADE approach. Subgroup and sensitivity analyses will be conducted to assess the robustness of the findings.

ETHICS AND DISSEMINATION

No ethical issues are foreseen. Results from this study will be published in a peer-reviewed journal and possibly presented at relevant national and international conferences.

TRIAL REGISTRATION NUMBER

CRD42014008976.

Emerging Pharmacologic Treatments for Adolescent Substance Use: Challenges and New Directions

Adolescence is a key period in the development of substance use and misuse. Substance use typically begins during adolescence and prevalence rates for many substance use disorders peak before age 21 years. Yet, despite clinical demand, treatments for youth rely almost entirely on psychosocial interventions that yield only modest benefit. One potential way to improve treatment effects is to augment the best available psychosocial interventions with pharmacotherapy. Although pharmacotherapy research has advanced care for adults with substance use disorders, no medication is indicated for adolescents and controlled trials with teenagers are scant. Optimizing treatments for youth will require closing this important gap in medication development research. In this paper we review the paucity of pharmacotherapy research for adolescent substance misuse, and we discuss how we can leverage human laboratory paradigms and technology to advance our understanding regarding if and how medications may improve treatment options for youths.

Pain and placebo in pediatrics: a comprehensive review of laboratory and clinical findings

Pain modulation by placebo mechanisms is one of the most robust and best-studied phenomena, yet almost all research investigating the mechanisms and implications of the placebo analgesia are based on adult research. After highlighting crucial aspects that need to be considered in studying pain modulation in children, this comprehensive review examines studies related to pain modulation with an emphasis on factors such as age, neural development and pain measures. We critically discuss psychological mechanisms underlying placebo effects, including (1) verbally induced expectations, (2) conditioning and learning mechanisms, and (3) child-parent-physician interactions. Taken together, research suggests that placebo mechanisms can affect therapeutic outcomes and potentially be exploited clinically to improve clinical outcomes in pediatric population. Recommendations for further investigating the mechanistic bases and harnessing placebo effects for supportive therapeutic applications are given.

Comparative efficacy, acceptability, and safety of medicinal, cognitive-behavioral therapy, and placebo treatments for acute major depressive disorder in children and adolescents: a multiple-treatments meta-analysis

BACKGROUND

New generation antidepressant therapies, including serotonin-norepinephrine reuptake inhibitor (SNRIs) and selective serotonin reuptake inhibitors (SSRIs) were introduced in the late 1980s; however, few comprehensive studies compared the benefits and risks of various contemporary treatments for major depressive disorder (MDD) in pediatric patients.

OBJECTIVE

Multiple-treatments meta-analysis (MTM) was conducted to assess efficacy, acceptability, and safety of contemporary interventions in children and adolescents with MDD.

METHODS

Cochrane Library, AMED, CINAHL, EMBASE, LiLACS, MEDLINE, PSYCINFO, PSYNDEX, and Journal of Medicine and Pharmacy databases were searched for randomized controlled trials (RCTs) comparing medicinal interventions (citalopram, escitalopram, fluoxetine, mirtazapine, paroxetine, sertraline, venlafaxine), cognitive behavioral therapy (CBT), combined fluoxetine with CBT, and placebo treatment for acute MDD from January 1988 to March 2013. Treatment success, dropout rate, and suicidal ideation/attempt outcomes were measured. Bayesian methods were used to conduct a MTM including age and funding subgroups.

RESULTS

A total of 21 RCTs (4969 participants) were identified. Combined fluoxetine/CBT exhibited the highest efficacy, with fluoxetine alone superior to CBT, paroxetine, sertraline, citalopram, escitalopram, and placebo treatment. Sertraline, paroxetine, escitalopram, and venlafaxine showed superior acceptability to fluoxetine and combined fluoxetine/CBT. Combined fluoxetine/CBT combination was less safe, though CBT was safer than fluoxetine alone. Combined fluoxetine/CBT, fluoxetine, and mirtazapine exhibited the highest efficacy; sertraline, escitalopram, venlafaxine, and paroxetine were the best tolerated; and mirtazapine and venlafaxine were the safest.

CONCLUSIONS

Sertraline and mirtazapine exhibited optimally balanced efficacy, acceptability, and safety for first-line acute treatment of child and adolescent MDD.

Pediatric depression: an evidence-based update on treatment interventions

Depression is a common condition among children and adolescents, with lasting detrimental effects on health, and social and occupational functioning. Despite being well-positioned to treat depression, primary care providers (PCPs) cite significant barriers. This review aims to summarize recent evidence to provide practical guidance to PCPs on the management of pediatric depression in their practices. Following identification and assessment, PCPs should provide general initial management. Children and adolescents with mild depression can be managed with active support and symptom monitoring, while those with moderate-to-severe depression can be treated with psychotherapy and/or antidepressants, which may involve referral to mental health specialty care. Less is known about the treatment of depression in children under the age of 12 years, who may be candidates for earlier referral to mental health specialty care. PCPs have the potential to improve the recognition and management of depression in young people, having lasting individual and societal benefits.

Developmentally informed pharmacotherapy for child and adolescent depressive disorders

This article reviews evidence-based pharmacotherapy for children and adolescents with depression. Several randomized controlled trials (RCTs) support the use of fluoxetine for the treatment of childhood and adolescent depression as well as escitalopram in the treatment of adolescent depression. To date, one RCT has demonstrated the effectiveness of sertraline or citalopram for the treatment of major depressive disorder in youth. Only a small number of RCTs for depression have included children, and none of these trials were adequately powered to detect differences in the efficacy of medication between children and adolescents.

Insomnia moderates outcome of serotonin-selective reuptake inhibitor treatment in depressed youth

OBJECTIVE

Insomnia is evident in the majority of youth with depression, and is associated with poorer outcomes. There are limited data on the impact of insomnia in response to acute treatment, which is particularly relevant with serotonin-selective reuptake inhibitors, given their tendency to worsen sleep architecture.

METHODS

Three hundred nine children and adolescents (ages 7-18 years) were randomized to fluoxetine (n=157) or placebo (n=152) for 8-9 weeks (Emslie et al.1997, 2002). Substantial insomnia at baseline was defined as a child's depression rating scale-revised [CDRS-R] sleep item ≥ 4. Outcome measures were CDRS-R, response, and remission.

RESULTS

Insomnia was reported in 172/309 (55.7%) youth, and was associated with higher depression severity and greater fatigue, suicidal ideation, physical complaints, and decreased concentration. While response rates were similar in those with or without insomnia overall (51.7% vs. 55.7%), there is a significant difference by age group. Among adolescents, those with insomnia were less likely to respond to fluoxetine (39.2%; 20/51) than those without (65.9%; 27/41; p=0.013), while in children on fluoxetine, those with insomnia were more likely to respond to fluoxetine (69.4%; 25/36) than those without insomnia (41.4%; 12/29; p=0.027). Insomnia did not impact the response to placebo in either age group. Within adolescents, the overall least squares means for CDRS-R total score (across the 8 weeks of treatment) were significantly different between those who had insomnia versus those who did not within the fluoxetine group (43.65 [SE=1.31] vs. 36.58[SE=1.45], F=12.69, df=1, 169, p=0.0005; d=0.82), but not within the placebo group (44.91[SE=1.34] vs. 43.75[SE=1.68], F=0.29, df=1, 179, p=0.591; d=0.15).

CONCLUSIONS

While adolescents reporting substantial insomnia were less likely to respond to antidepressant treatment than those without insomnia, children were more responsive to fluoxetine when they had insomnia. Additional intervention targeting sleep disturbance may be warranted in adolescents.

Anxiety as a predictor of treatment outcome in children and adolescents with depression

OBJECTIVE

The aim of this study was to examine the impact of co-morbid illnesses on treatment outcomes in depressed children and adolescents aged 7-17 who were treated with fluoxetine.

METHOD

This data set was drawn from two large clinical trials involving children and adolescents with depression. Subjects with a diagnosis of major depressive disorder and depressive symptoms of at least moderate severity as defined by a Children's Depression Rating Score, Revised (CDRS-R) total score >or=40 and a Clinical Global Impressions-Severity (CGI-S) rating >or=4 were included. Subjects were randomized to receive fluoxetine or placebo over an 8-week period. Predictor analyses examining two primary outcomes were conducted: (1) Response based on Clinical Global Impressions-Improvement (CGI-I) score of 1 or 2, and (2) remission based on CDRS-R score of <or=28. Logistic regression models were run to assess whether anxiety disorders were a predictor of response or remission.

RESULT

A total of 309 study participants were included. The only factor found to influence response was treatment with fluoxetine (p = 0.022, odds ratio [OR] = 2.08, 95% confidence interval [CI] 1.30, 3.31). Several factors were found to influence remission: Treatment with fluoxetine (p < 0.0001, OR = 3.17, 95% CI 1.80, 5.57), gender (p = 0.024, OR = 1.90, 95% CI 1.09, 3.30), and number of co-morbid diagnoses (p = 0.026, OR 0.73, 95% CI 0.55, 0.96).

CONCLUSION

Anxiety disorders alone did not predict response or remission, but the total number of co-morbid illnesses was associated with remission in depressed children and adolescents treated with fluoxetine.

Predictors of placebo response in randomized controlled trials of psychotropic drugs for children and adolescents with internalizing disorders

OBJECTIVE

The aim of this study was to assess predictors of placebo response in all available short-term, placebo-controlled trials of psychotropic drugs for children and adolescents with internalizing disorders, major depressive disorder (MDD), obsessive compulsive disorder (OCD,) and anxiety disorders (ANX) exclusive of OCD and posttraumatic stress disorder (PTSD).

METHOD

We reviewed the literature relevant to the use of psychotropic medication in children and adolescents with internalizing disorders, restricting our review to double-blind studies including a placebo arm. Placebo response, defined according to each trial's primary response outcome variable and Clinical Global Impressions-Improvement, when available, and potential predictive variables were extracted from 40 studies.

RESULTS

From 1972 to 2007, we found 23 trials that evaluated the efficacy of psychotropic medication involving youth with MDD, 7 pertaining to youths with OCD, and 10 pertaining to youths with ANX (N = 2,533 patients in placebo arms). For all internalizing disorders combined, predictors of nonresponse to placebo were the percentage of Caucasian patients included in the study and the duration of the disorder: Both variables were negatively correlated with the percent of placebo responders. The type of disorder was found to predict the robustness of placebo response: (OCD < ANX < MDD). For a subset of MDD studies, we found that baseline illness severity tended to be negatively correlated with placebo response. Finally, trial "success" was significantly associated with lower placebo response rate.

CONCLUSION

Predictors of placebo response in internalizing disorders of youths parallel those in adult studies, with the exception of race. These predictors should be considered when designing placebo-controlled trials in youths to enhance findings of true drug-placebo differences.

Escitalopram in the treatment of adolescent depression: a randomized placebo-controlled multisite trial

OBJECTIVE

This article presents the results from a prospective, randomized, double-blind, placebo-controlled trial of escitalopram in adolescent patients with major depressive disorder.

METHOD

Male and female adolescents (aged 12-17 years) with DSM-IV-defined major depressive disorder were randomly assigned to 8 weeks of double-blind treatment with escitalopram 10 to 20 mg/day (n = 155) or placebo (n = 157). The primary efficacy parameter was change from baseline to week 8 in Children's Depression Rating Scale-Revised (CDRS-R) score using the last observation carried forward approach.

RESULTS

A total of 83% patients (259/312) completed 8 weeks of double-blind treatment. Mean CDRS-R score at baseline was 57.6 for escitalopram and 56.0 for placebo. Significant improvement was seen in the escitalopram group relative to the placebo group at endpoint in CDRS-R score (-22.1 versus -18.8, p =.022; last observation carried forward). Adverse events occurring in at least 10% of escitalopram patients were headache, menstrual cramps, insomnia, and nausea; only influenza-like symptoms occurred in at least 5% of escitalopram patients and at least twice the incidence of placebo (7.1% versus 3.2%). Discontinuation rates due to adverse events were 2.6% for escitalopram and 0.6% for placebo. Serious adverse events were reported by 2.6% and 1.3% of escitalopram and placebo patients, respectively, and incidence of suicidality was similar for both groups.

CONCLUSIONS

In this study, escitalopram was effective and well tolerated in the treatment of depressed adolescents.

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.

Early prediction of acute antidepressant treatment response and remission in pediatric major depressive disorder

OBJECTIVE

: Less than half of youths achieve remission (minimal to no symptoms) after acute antidepressant treatment. Early identification of who will or will not respond to treatment and achieve remission may help clinicians formulate treatment decisions and shorten the time spent on ineffective treatments. In a prospective open-label fluoxetine study, we investigate indicators of acute treatment response and remission.

METHOD

: One hundred sixty-eight children and adolescents, ages 7 to 18 years, with primary diagnoses of major depressive disorder received 12 weeks of fluoxetine treatment. The youths were evaluated using the Kiddie Schedule for Affective Disorders and Schizophrenia. The outcome measure included the Children's Depression Rating Scale-Revised.

RESULTS

: Positive first-degree family history of depression was the only baseline demographic and clinical characteristic that predicted a favorable treatment response (p =.01). The rate of symptom improvement, however, is a good indicator of acute treatment response. A significant symptom reduction (approximately 50%) by week 4 is needed to achieve remission at the end of acute treatment.

CONCLUSIONS

: This study demonstrated that the rate of symptom improvement during early weeks of acute fluoxetine treatment is a good indicator of remission. Treatment approach may be reevaluated and modified as early as week 4 during acute treatment.Clinical trials registration information-Determining Optimal Continuation Treatment Duration for Depressed Children and Adolescents. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00332787.

Differential sensitivity to SSRI and tricyclic antidepressants in juvenile and adult mice of three strains

Clinical studies have shown differential efficacy of several antidepressants in children and adolescents compared to adults, yet few animal studies have sought to characterize this phenomenon. We compared effects of fluoxetine and imipramine in two common behavioral assays that hold high predictive validity for antidepressant activity, tail suspension and forced swim test, using juvenile (5 weeks) and adult (12 weeks) mice from 3 strains. C57BL/6J-Tyr(c-Brd) (C57), hybrid C57BL/6J-Tyr(c-Brd)x129S5/SvEvBrd (F2), and Balb/cAnNTac (Balb/C) mice were tested in forced swim test and tail suspension after i.p. dosing with either fluoxetine or imipramine. Brain tissues were analyzed to evaluate levels of VMAT2, a possible modulator of age-dependent sensitivity to antidepressants. Imipramine had more consistent antidepressant effect across age groups and strains. Imipramine increased struggle in mice of both ages. Fluoxetine did not have an effect on immobility in Balb/C of both ages in tail suspension. Fluoxetine also did not increase forced swim struggle behavior in juvenile mice of all strains, but was effective in increasing struggle in adults. Juvenile mice had higher immobility and lower struggle than adults in forced swim, and juveniles also had higher immobility in tail suspension test for Balb/C and C57. In addition, VMAT2 levels were increased in juveniles. These results confirm that standard antidepressants produce effects in both juveniles and adults but age-related differences were evident in both tests. Further examination of these effects is needed to determine whether it may be related to age-dependent difference in the clinical response to antidepressants of these classes.

Are child and adolescent responses to placebo higher in major depression than in anxiety disorders? A systematic review of placebo-controlled trials

BACKGROUND

In a previous report, we hypothesized that responses to placebo were high in child and adolescent depression because of specific psychopathological factors associated with youth major depression. The purpose of this study was to compare the placebo response rates in pharmacological trials for major depressive disorder (MDD), obsessive compulsive disorder (OCD) and other anxiety disorders (AD-non-OCD).

METHODOLOGY AND PRINCIPAL FINDINGS

We reviewed the literature relevant to the use of psychotropic medication in children and adolescents with internalized disorders, restricting our review to double-blind studies including a placebo arm. Placebo response rates were pooled and compared according to diagnosis (MDD vs. OCD vs. AD-non-OCD), age (adolescent vs. child), and date of publication. From 1972 to 2007, we found 23 trials that evaluated the efficacy of psychotropic medication (mainly non-tricyclic antidepressants) involving youth with MDD, 7 pertaining to youth with OCD, and 10 pertaining to youth with other anxiety disorders (N = 2533 patients in placebo arms). As hypothesized, the placebo response rate was significantly higher in studies on MDD, than in those examining OCD and AD-non-OCD (49.6% [range: 17-90%] vs. 31% [range: 4-41%] vs. 39.6% [range: 9-53], respectively, ANOVA F = 7.1, p = 0.002). Children showed a higher stable placebo response within all three diagnoses than adolescents, though this difference was not significant. Finally, no significant effects were found with respect to the year of publication.

CONCLUSION

MDD in children and adolescents appears to be more responsive to placebo than other internalized conditions, which highlights differential psychopathology.

Texas Children's Medication Algorithm Project: update from Texas Consensus Conference Panel on Medication Treatment of Childhood Major Depressive Disorder

OBJECTIVE

To revise and update consensus guidelines for medication treatment algorithms for childhood major depressive disorder based on new scientific evidence and expert clinical consensus when evidence is lacking.

METHOD

A consensus conference was held January 13-14, 2005, that included academic clinicians and researchers, practicing clinicians, administrators, consumers, and families. The focus was to review, update, and incorporate the most current data to inform and recommend specific pharmacological approaches and clinical guidance for treatment of major depressive disorder in children and adolescents.

RESULTS

Consensually agreed on medication algorithms for major depression (with and without psychosis) and comorbid attention-deficit disorders were updated. These revised algorithms also incorporated approaches to address issues of suicidality, aggression, and irritability. Stages 1, 2, and 3 of the algorithm consist of selective serotonin reuptake inhibitor and norepinephrine serotonin reuptake inhibitor medications whose use is supported by controlled, acute clinical trials and clinical experience. Recent studies provide support that selective serotonin reuptake inhibitors in addition to fluoxetine are still encouraged as first-line interventions. The need for additional assessments, precautions, and monitoring is emphasized, as well as continuation and maintenance treatment.

CONCLUSIONS

Evidence and expert clinical consensus support the use of selected antidepressants in the treatment of depression in youths. The use of the recommended antidepressant medications requires appropriate monitoring of suicidality and potential adverse effects and consideration of other evidence-based treatment alternatives such as cognitive behavioral therapies.