Selective serotonin reuptake inhibitors in pediatric depression: is the balance between benefits and risks favorable?

BDNF and its Role in the Alcohol Abuse Initiated During Early Adolescence: Evidence from Preclinical and Clinical Studies

Brain-derived neurotrophic factor (BDNF) is a crucial brain signaling protein that is integral to many signaling pathways. This neurotrophin has shown to be highly involved in brain plastic processes such as neurogenesis, synaptic plasticity, axonal growth, and neurotransmission, among others. In the first part of this review, we revise the role of BDNF in different neuroplastic processes within the central nervous system. On the other hand, its deficiency in key neural circuits is associated with the development of psychiatric disorders, including alcohol abuse disorder. Many people begin to drink alcohol during adolescence, and it seems that changes in BDNF are evident after the adolescent regularly consumes alcohol. Therefore, the second part of this manuscript addresses the involvement of BDNF during adolescent brain maturation and how this process can be negatively affected by alcohol abuse. Finally, we propose different BNDF enhancers, both behavioral and pharmacological, which should be considered in the treatment of problematic alcohol consumption initiated during the adolescence.

Efficacy of interventions for suicide and self-injury in children and adolescents: a meta-analysis

Despite increased numbers of children and adolescents seeking and receiving mental health treatment, rates of self-injurious thoughts and behaviors (SITBs) in youth are rising. In the hopes of aiding ongoing efforts to alleviate the burden of SITBs in this vulnerable population, the present study summarizes current knowledge on the efficacy of SITB interventions in children and adolescents. We conducted a meta-analysis of randomized controlled trials (RCTs) assessing treatment effects on SITBs in child and adolescent populations. A total of 112 articles comprising 558 effect sizes were included in analyses. Nearly all interventions produced nonsignificant reductions in SITBs. For binary SITB outcomes, a nonsignificant treatment effect was detected, with an RR of 1.06 (95% CIs [0.99, 1.14]). For continuous SITB outcomes, analyses also yielded a nonsignificant treatment effect (g = - 0.04 [- 0.12, 0.05]). These patterns were largely consistent across SITB outcomes, regardless of intervention type, treatment components, sample and study characteristics, and publication year. Our findings highlight opportunities for improving SITB intervention development and implementation in child and adolescent populations. The most efficacious interventions are likely to directly target the causes of SITBs; therefore, future research is needed to identify the causal processes underlying the onset and maintenance of SITBs in youth.

Chronic SSRI Treatment, but Not Norepinephrine Reuptake Inhibitor Treatment, Increases Neurogenesis in Juvenile Rats

There has been growing recognition that major depressive disorder is a serious medical disorder that also affects children. This has been accompanied by an increased use of antidepressant drugs in adolescents; however, not all classes of antidepressants are effective in children and adolescents. There is an increasing need to understand the differences in antidepressant action in different developmental stages. There are some data indicating that the behavioral effect of chronic antidepressant treatment in adult rodents is dependent on hippocampal neurogenesis; however, it is not known which classes of antidepressant drugs induce hippocampal neurogenesis in adolescent rodents. Three classes of antidepressant drugs were tested in two age groups of Sprague Dawley rats, pre-adolescent (postnatal days 11–24) and adolescent (postnatal days 21–34): monoamine oxidase inhibitors (MAOIs); selective serotonin reuptake inhibitors (SSRIs); serotonin norepinephrine reuptake inhibitors (SNRIs); and tricyclic antidepressants (TCAs). To address which classes of antidepressant drugs might alter the rate of mitogenesis in neural progenitor cells in an adolescent rodent model, adolescent Sprague Dawley rats were treated with the thymidine analog 5-bromo-deoxy-2′-uridine (BrdU) on postnatal days 21 and 22 and antidepressant drugs or vehicle for 14 days (postnatal days 21–34). To address which classes of antidepressant drugs might alter the rate of neurogenesis, postnatal day-21 Sprague Dawley rats were treated with antidepressant drugs or vehicle for 14 days (postnatal days 21–34) and BrdU on postnatal days 33 and 34. In both experimental paradigms, BrdU-positive cells in the subgranular zone and the granule cell layer were counted. Newborn neurons were identified in the neurogenic paradigm by identifying cells expressing both the neuronal specific marker NeuN and BrdU using confocal microscopy. Only the SSRI fluoxetine significantly altered the basal mitogenic and neurogenic rates in adolescent rats. Treatment with the monoamine oxidase inhibitor (MAOI) tranylcypromine (TCP) and the TCA desipramine did not alter the rate of hippocampal neurogenesis in the adolescent rats. This is consistent with human clinical observations, where only SSRIs have efficacy for treatment of depression in patients under the age of 18. In pre-adolescent rats, postnatal days 11–24, none of the drugs tested significantly altered the basal mitogenic or neurogenic rates. All of the classes of antidepressant drugs are known to induce hippocampal neurogenesis in adult rats. The mechanisms of action underlying this developmental difference in antidepressant drug action between juveniles and adults are not known.

The Resilient Phenotype Induced by Prophylactic Ketamine Exposure During Adolescence Is Mediated by the Ventral Tegmental Area-Nucleus Accumbens Pathway

BACKGROUND

Major depressive disorder is prevalent in children and adolescents and is associated with a high degree of morbidity throughout life, with potentially devastating personal consequences and public health impact. The efficacy of ketamine (KET) as an antidepressant has been demonstrated in adolescent rodents; however, the neurobiological mechanisms underlying these effects are unknown. Recent evidence showed that KET reverses stress-induced (i.e., depressive-like) deficits within major mesocorticolimbic regions, such as the prefrontal cortex, nucleus accumbens (NAc), and hippocampus, in adult rodents. However, little is known about KET's effect in the ventral tegmental area (VTA), which provides the majority of dopaminergic input to these brain regions.

METHODS

We characterized behavioral, biochemical, and electrophysiological effects produced by KET treatment in C57BL/6J male mice during adolescence (n = 7-10 per condition) within the VTA and its major projection regions, namely, the NAc and prefrontal cortex. Subsequently, molecular targets within the VTA-NAc projection were identified for viral gene transfer manipulations to recapitulate the effects of stress or KET treatment.

RESULTS

Repeated KET treatment produced a robust proresilient response to chronic social defeat stress. This effect was largely driven by Akt signaling activity within the VTA and NAc, and it could be blocked or recapitulated through direct Akt-viral-mediated manipulation. Additionally, we found that the KET-induced resilient phenotype is dependent on VTA-NAc, but not VTA-prefrontal cortex, pathway activity.

CONCLUSIONS

These findings indicate that KET exposure during adolescence produces a proresilient phenotype mediated by changes in Akt intracellular signaling and altered neuronal activity within the VTA-NAc pathway.

Further Support for the Involvement of Genetic Variants Related to the Serotonergic Pathway in the Antidepressant Response in Children and Adolescents After a 12-Month Follow-Up: Impact of the HTR2A rs7997012 Polymorphism

Objective: Fluoxetine is an effective and well-tolerated pharmacological treatment for children and adolescents with major depressive disorder (MDD). However, a high percentage of patients do not respond. There is a substantial genetic contribution to this variable clinical outcome. Based on previous genetic results of our group and given the lack of pharmacogenetics studies of antidepressant response with a long follow-up period, we evaluated the influence of single nucleotide polymorphisms (SNPs) in genes related to the serotonergic pathway on remission and recovery in children and adolescents diagnosed with MDD after 12 months of initiating fluoxetine treatment. Methods: The assessment was performed in 46 patients. All of them were visited at least once a month during the 12-month follow-up. Psychiatrists interviewed patients and their parents to explore clinical improvement. A total of 75 genotyped SNPs in 10 candidate genes were included in the genetic association analysis with remission and recovery. Bonferroni correction for multiple testing was applied to avoid false positive results. Results: The HTR2A rs7997012 SNP was significantly associated after Bonferroni correction with clinical improvement. Particularly, the homozygotes for the major allele (GG) showed the highest percentage of remitters and the highest score reductions on the Clinical Global Impressions-Severity (CGI-S) scale. Moreover, although the results were on the border of statistical significance, the GG homozygotes also tended to experience fewer readmissions during the follow-up period Conclusions: These results provide more evidence of the involvement of genetic variants related to the serotonergic pathway in the antidepressant response. Studies with larger cohorts are needed to integrate all relevant variants into clinical predictors of antidepressant response.

Selective Serotonin Reuptake Inhibitors and Violent Crime: A Cohort Study

BACKGROUND

Although selective serotonin reuptake inhibitors (SSRIs) are widely prescribed, associations with violence are uncertain.

METHODS AND FINDINGS

From Swedish national registers we extracted information on 856,493 individuals who were prescribed SSRIs, and subsequent violent crimes during 2006 through 2009. We used stratified Cox regression analyses to compare the rate of violent crime while individuals were prescribed these medications with the rate in the same individuals while not receiving medication. Adjustments were made for other psychotropic medications. Information on all medications was extracted from the Swedish Prescribed Drug Register, with complete national data on all dispensed medications. Information on violent crime convictions was extracted from the Swedish national crime register. Using within-individual models, there was an overall association between SSRIs and violent crime convictions (hazard ratio [HR] = 1.19, 95% CI 1.08-1.32, p < 0.001, absolute risk = 1.0%). With age stratification, there was a significant association between SSRIs and violent crime convictions for individuals aged 15 to 24 y (HR = 1.43, 95% CI 1.19-1.73, p < 0.001, absolute risk = 3.0%). However, there were no significant associations in those aged 25-34 y (HR = 1.20, 95% CI 0.95-1.52, p = 0.125, absolute risk = 1.6%), in those aged 35-44 y (HR = 1.06, 95% CI 0.83-1.35, p = 0.666, absolute risk = 1.2%), or in those aged 45 y or older (HR = 1.07, 95% CI 0.84-1.35, p = 0.594, absolute risk = 0.3%). Associations in those aged 15 to 24 y were also found for violent crime arrests with preliminary investigations (HR = 1.28, 95% CI 1.16-1.41, p < 0.001), non-violent crime convictions (HR = 1.22, 95% CI 1.10-1.34, p < 0.001), non-violent crime arrests (HR = 1.13, 95% CI 1.07-1.20, p < 0.001), non-fatal injuries from accidents (HR = 1.29, 95% CI 1.22-1.36, p < 0.001), and emergency inpatient or outpatient treatment for alcohol intoxication or misuse (HR = 1.98, 95% CI 1.76-2.21, p < 0.001). With age and sex stratification, there was a significant association between SSRIs and violent crime convictions for males aged 15 to 24 y (HR = 1.40, 95% CI 1.13-1.73, p = 0.002) and females aged 15 to 24 y (HR = 1.75, 95% CI 1.08-2.84, p = 0.023). However, there were no significant associations in those aged 25 y or older. One important limitation is that we were unable to fully account for time-varying factors.

CONCLUSIONS

The association between SSRIs and violent crime convictions and violent crime arrests varied by age group. The increased risk we found in young people needs validation in other studies.

Repeated ketamine exposure induces an enduring resilient phenotype in adolescent and adult rats

BACKGROUND

Major depressive disorder afflicts up to 10% of adolescents. However, nearly 50% of those afflicted are considered nonresponsive to available treatments. Ketamine, a noncompetitive N-methyl-D-aspartate receptor antagonist has shown potential as a rapid-acting and long-lasting treatment for major depressive disorder in adults. Thus, the effectiveness and functional consequences of ketamine exposure during adolescence were explored.

METHODS

Adolescent male rats (postnatal day [PD] 35) received two ketamine (0, 5, 10, or 20 mg/kg) injections, 4 hours apart, after exposure to day 1 of the forced swim test (FST). The next day, rats were reexposed to the FST to assess ketamine-induced antidepressant-like responses. Separate groups were exposed to chronic unpredictable stress to confirm findings from the FST. After these initial experiments, adolescent naive rats were exposed to either 1 or 15 consecutive days (PD35-49) of ketamine (20 mg/kg) twice daily. Ketamine's influence on behavioral reactivity to rewarding (i.e., sucrose preference) and aversive (i.e., elevated plus-maze, FST) circumstances was then assessed 2 months after treatment. To control for age-dependent effects, adult rats (PD75-89) were exposed to identical experimental conditions.

RESULTS

Ketamine (20 mg/kg) reversed the chronic unpredictable stress-induced depression-like behaviors in the FST. Repeated ketamine exposure resulted in anxiolytic- and antidepressant-like responses 2 months after drug exposure. None of the ketamine doses used were capable of inducing drug-seeking behaviors as measured by place preference conditioning.

CONCLUSIONS

Repeated ketamine exposure induces enduring resilient-like responses regardless of age of exposure. These findings point to ketamine, and its repeated exposure, as a potentially useful antidepressant during adolescence.

Escitalopram in the treatment of adolescent depression: a randomized, double-blind, placebo-controlled extension trial

OBJECTIVE

The purpose of this study was to evaluate the extended efficacy, safety, and tolerability of escitalopram relative to placebo in adolescents with major depressive disorder (MDD).

METHODS

Adolescents (12-17 years) who completed an 8-week randomized, double-blind, flexible-dose, placebo-controlled, lead-in study of escitalopram 10-20 mg versus placebo could enroll in a 16-24-week, multisite extension trial; patients maintained the same lead-in randomization (escitalopram or placebo) and dosage (escitalopram 10 or 20 mg/day, or placebo) during the extension. The primary efficacy was Children's Depression Rating Scale-Revised (CDRS-R) change from the lead-in study baseline to treatment week 24 (8-week lead-in study plus 16-week extension); the secondary efficacy was Clinical Global Impressions-Improvement (CGI-I) score at week 24. All efficacy analyses used the last observation carried forward (LOCF) approach; sensitivity analyses used observed cases (OC) and mixed-effects model for repeated measures (MMRM). Safety was evaluated via adverse event (AE) reports and the clinician-rated Columbia-Suicide Severity Rating Scale (C-SSRS).

RESULTS

Following lead-in, 165 patients enrolled in the double-blind extension (82 placebo; 83 escitalopram); 40 (48.8%) placebo and 37 (44.6%) escitalopram patients completed treatment. CDRS-R total score improvement was significantly greater for escitalopram than for placebo (p=0.005, LOCF; p=0.014; MMRM). Response rates (CDRS-R ≥ 40% reduction from baseline [adjusted and unadjusted] and CGI-I ≤ 2) were significantly higher for escitalopram than for placebo (LOCF); remission rates (CDRS-R ≤ 28) were 50.6% for escitalopram and 35.7% for placebo (p=0.002). OC analyses were not significantly different between groups. The most frequent escitalopram AEs (≥ 5% and more frequent than placebo) were headache, nausea, insomnia, vomiting, influenza-like symptoms, diarrhea, and urinary tract infection. Most AEs were mild/moderate and not related to the study drug. AEs suggestive of self-harm occurred in 5.7% and 7.1% of placebo and escitalopram patients. Occurrence of suicidal behavior and/or suicidal ideation assessed by C-SSRS was 10.9% (14/128) for placebo and 14.5% (19/131) for escitalopram.

CONCLUSIONS

Extended use of escitalopram was generally safe and resulted in modest improvement in efficacy in adolescents with MDD.

Depressed Adolescents Treated with Exercise (DATE): A pilot randomized controlled trial to test feasibility and establish preliminary effect sizes

The Depressed Adolescents Treated with Exercise (DATE) study evaluated a standardized aerobic exercise protocol to treat nonmedicated adolescents that met DSM-IV-TR criteria for major depressive disorder. From an initial screen of 90 individuals, 30 adolescents aged 12-18 years were randomized to either vigorous exercise (EXER) (>12 kg/kcal/week [KKW]) or a control stretching (STRETCH) activity (< 4 KKW) for 12 weeks. The primary outcome measure was the blinded clinician rating of the Children's Depression Rating Scale - Revised (CDRS-R) to assess depression severity and Actical (KKW) accelerometry 24hr/7days a week to assess energy expenditure and adherence. Follow-up evaluations occurred at weeks 26 and 52. The EXER group averaged 77% adherence and the STRETCH group 81% for meeting weekly target goals for the 12 week intervention based on weekly sessions completed and meeting KKW requirements. There was a significant increase in overall weekly KKW expenditures (p < .001) for both groups with the EXER group doubling the STRETCH group in weekly energy expenditure. Depressive symptoms were significantly reduced from baseline for both groups with the EXER group improving more rapidly than STRETCH after six weeks (p < .016) and nine weeks (p < .001). Both groups continued to improve such that there were no group differences after 12 weeks (p = .07). By week 12, the exercise group had a 100% response rate (86% remission), whereas the stretch group response rate was 67% (50% remission) (p = .02). Both groups had improvements in multiple areas of psychosocial functioning related to school and relationships with parents and peers. Anthropometry reflected decreased waist, hip and thigh measurements (p = .02), more so for females than males (p = .05), but there were no weight changes for either gender. The EXER group sustained 100% remission at week 26 and 52. The STRETCH group had 80% response and 70% remission rates at week 26 and by week 52 only one had not fully responded. The study provides support for the use of exercise as a non-medication intervention for adolescents with major depressive disorders when good adherence and energy expenditure (KKW) are achieved.

Child and adolescent depression: psychotherapeutic, ethical, and related nonpharmacologic considerations for general psychiatrists and others who prescribe

Depression is a common, recurring disorder affecting millions of youth at some point before they reach mature adulthood. Given the shortage of and uneven distribution of psychiatrists who have completed specialized fellowships in child and adolescent psychiatry, a significant number of depressed youth will receive their pharmacotherapy from general psychiatrists and other prescribers with varying degrees of interest, training, and even willingness to treat children and adolescents. For general psychiatrists who will prescribe antidepressants for minors, knowledge of the training and expertise of nonphysician mental health professionals, the psychotherapies they may employ, and familiarity with school services are essential. Physicians who typically work only with adults will also need familiarity with differing ethical, legal, and regulatory issues and standards applicable to pediatric psychopharmacology. General psychiatrists, pediatricians, family physicians, nurse practitioners, and others contribute greatly to the care of depressed children, adolescents, and their families, and many find this work to be a very rewarding part of their professional practices.

Impact of initiation timing of SSRI or SNRI on depressed adolescent healthcare utilization and costs

BACKGROUND

Adolescents with newly diagnosed depression may not receive timely antidepressant therapy. Clinical and economic effects of early versus late treatment initiation are unclear.

OBJECTIVE

To compare effects of early versus late initiation of second-generation (SSRI/SNRI) antidepressants on emergency room (ER) visits, hospitalizations and healthcare costs in adolescents with depression.

METHODS

Patients aged 12-17 with a diagnosis of depression were identified in a claims database (1999-2007). Patients initiating antidepressants within 1 month of initial diagnosis were considered early initiators; patients initiating within 2-12 months were late initiators. Clinical resource use and healthcare costs were measured during the 6-month pre-index and 12-month post-index (study) periods and compared descriptively between groups. Logistic regression compared healthcare services utilization; a generalized linear model compared costs. All models were adjusted for baseline characteristics, including demographics, comorbidities, and healthcare services utilization.

RESULTS

A total of 7344 adolescents met study criteria. 4415 (60%) initiated antidepressant treatment within 1 month of diagnosis. At baseline, early initiators had more all-cause inpatient visits (14 vs. 7%) and all-cause ER visits than late initiators (25 vs. 21%, both p<0.01). They had higher medical ($1434 vs. $1160) and total costs ($1565 vs. $1290) (both p<0.01). In the study period, late initiators had higher risk of ER visits (OR=1.13, p=0.03). They incurred higher medical costs ($5415 vs. $4061) and higher total healthcare costs ($6001 vs. $4907), but lower adjusted drug costs ($767 vs. $888) (all p<0.01).

LIMITATIONS

Clinical data are scarce in the claims database, and the ability to observe disease severity and reasons for delayed treatment is limited. The definition of early and late initiation was based on empirical analysis, and no clear cutoff was identified beyond what was observed in the data.

CONCLUSIONS

Adolescents who initiated SSRI/SNRI therapy earlier experienced lower risk of ER visits and had lower total costs compared to late initiators.

Short- and long-term functional consequences of fluoxetine exposure during adolescence in male rats

BACKGROUND

Fluoxetine (FLX), a selective serotonin reuptake inhibitor, is prescribed for the treatment of major depressive disorder in young populations. Here, we explore the short- and long-term consequences of adolescent exposure to FLX on behavioral reactivity to emotion-eliciting stimuli.

METHODS

Adolescent male rats received FLX (10 mg/kg) twice daily for 15 consecutive days (postnatal days 35-49). The influence of FLX on behavioral reactivity to rewarding and aversive stimuli was assessed 24 hours (short-term) or 3 weeks after FLX treatment (long-term). A separate group of adult rats was also treated with FLX (postnatal days 65-79) and responsiveness to forced swimming was assessed at identical time intervals as with the adolescents.

RESULTS

Fluoxetine exposure during adolescence resulted in long-lasting decreases in behavioral reactivity to forced swimming stress and enhanced sensitivity to sucrose and to anxiety-eliciting situations in adulthood. The FLX-induced anxiety-like behavior was alleviated by re-exposure to FLX in adulthood. Fluoxetine treatment during adolescence also impaired sexual copulatory behaviors in adulthood. Fluoxetine-treated adult rats did not show changes in behavioral reactivity to forced swim stress as observed in those treated during adolescence and tested in adulthood.

CONCLUSIONS

Treating adolescent rats with FLX results in long-lived complex outputs regulated by the emotional valence of the stimulus, the environment in which it is experienced, and the brain circuitry likely being engaged by it. Our findings highlight the need for further research to improve our understanding of the alterations that psychotropic exposure may induce on the developing nervous system and the potential enduring effects resulting from such treatments.

From TADS and SOFTADS to TORDIA and beyond: what's new in the treatment of adolescent depression?

Major depressive disorder in adolescents is associated with significant morbidity and mortality. Major advances have been made in recent years in the treatment of adolescent depression, with promising outcomes. However, limitations of currently available treatments have prompted attempts to better understand pediatric depression from a broader perspective and to develop more effective treatment strategies in the future.

DATE: Depressed adolescents treated with exercise: Study rationale and design for a pilot study

There is an important need for non-medication interventions for depressed youth. The aim of this study is to evaluate the feasibility of using a standardized aerobic exercise regime to treat non-medicated clinically depressed adolescents based on adherence and completion rates, including 1) establishing effect sizes for the primary outcomes including the Chidren's Depression Rating Scale - Revised (CDRS-R) and Actical (energy expenditure data) as well as selected secondary outcomes; (e.g., Clinical Global Improvement, depression rating scales, exercise logs, attitudes), and 2) determining whether moderate to strenuous exercise (12 kcal/kg/week [KKW]) versus a control stretching activity (<4 KKW) for 12 weeks leads to a clinically meaningful reduction in depressive symptoms and/or improved psychosocial functioning. The challenge is to develop an exercise intervention that can motivate a typically sedentary depressed adolescent to exercise on a regular basis. The goal is to demonstrate that exercise alone can provide an important and effective non-medication intervention for adolescent depression. This paper reports on the rationale and design of a pilot study which aims to inform the design of a larger trial to evaluate the efficacy of aerobic exercise to treat adolescent depression. After describing the case for exercise within the broader context of the prevalence of adolescent depression and other treatments, the paper describes the intervention and procedures for data collection.

Treatment with escitalopram but not desipramine decreases escape latency times in a learned helplessness model using juvenile rats

RATIONALE

The pharmacological treatment of depression in children and adolescents is different from that of adults due to the lack of efficacy of certain antidepressants in the pediatric age group. Our current understanding of why these differences occur is very limited.

OBJECTIVES

To develop more effective treatments, a juvenile animal model of depression was tested to validate it as a possible model to specifically study pediatric depression.

MATERIALS AND METHODS

Procedures for use with juvenile rats at postnatal day (PND) 21 and 28 were adapted from the adult learned helplessness model in which, 24 h after exposure to inescapable stress, animals are unable to remove themselves from an easily escapable stressor. Rats were treated for 7 days with either the selective serotonin reuptake inhibitor escitalopram at 10 mg/kg or the tricyclic antidepressant desipramine at 3, 10, or 15 mg/kg to determine if treatment could decrease escape latency times.

RESULTS

Escitalopram treatment was effective at decreasing escape latency times in all ages tested. Desipramine treatment did not decrease escape latency times for PND 21 rats, but did decrease times for PND 28 and adult animals.

CONCLUSIONS

The learned helplessness model with PND 21 rats predicts the efficacy of escitalopram and the lack of efficacy of desipramine seen in the treatment of pediatric depression. These findings suggest that the use of PND 21 rats in a modified learned helplessness procedure may be a valuable model of human pediatric depression that can predict pediatric antidepressant efficacy and be used to study antidepressant mechanisms involved in pediatric depression.

Antidepressant-coincident mania in children and adolescents treated with selective serotonin reuptake inhibitors

Several factors have amplified concern about the possibility that antidepressant medication may contribute to induction of pediatric mania. These include the high rate of antidepressant medication prescription, the recent surge in the rate of diagnosis of pediatric bipolar disorder in the USA, and a growing number of case reports and clinical studies showing coincidence of manic symptoms with antidepressant pharmacotherapy in both youths and adults. However, the question of how medications and manic symptoms might be related is complicated, and decisive research studies with rigorous designs for evaluating the issues have not been published. The situation makes it difficult for practitioners to make good, evidence-based decisions. The scientific literature is ambiguous, and the stakes are high. We review the extant literature, offer seven different conceptual models of how medication and mania might be related, and comment on the evidence and clinical implications of each.

Alpha-2 adrenergic-induced changes in rectal temperature in adult and 13-day old rats following acute and repeated desipramine administration

Background

The effects of acute and repeated treatment with desipramine on the functional response of α₂-adrenoceptors were tested in adult and 13-day old rats. The functional response measured was hypothermia that was induced by brimonidine, an α₂-adrenoceptor agonist. The change in the extent of the brimonidine-induced hypothermia following pretreatment with either single or 4 twice-daily injections of desipramine was compared in 13-day old and adult (65–75 days old) male rats.

Results

Brimonidine, alone, lowered rectal temperature to a greater extent in juvenile than in adult rats, and this response was dose-dependently blocked by the selective α₂-adrenoceptor antagonist, RX821002, in both groups of rats. Single desipramine administration lowered rectal temperature in the absence of brimonidine in adult but not in juvenile rats. The adult rats developed tolerance to this hypothermic effect after 4 days of desipramine treatment (10 mg/kg twice daily). Repeated desipramine treatment of adult rats also resulted in an enhancement in the brimonidine-induced hypothermic effect 24 h after the last dose, a time when above 90% of desipramine and its metabolite, desmethyldesipramine, had cleared the brain, but not at 14, 48 or 96 h after the last dose. In juvenile rats repeated injections of desipramine (3 mg/kg twice daily for 4 days) had no effect on the α₂-agonist-induced hypothermia when brimonidine was given 14, 24, 63 and 96 h after the last dose of desipramine.

Conclusion

The results suggest that juvenile rats response differently than adult rats to agonist stimulation of α₂-adrenoceptors with and without pretreatment with the antidepressant desipramine. In the absence of desipramine pretreatment, the α₂-adrenoceptor-induced hypothermic effect in juvenile rats is greater than in adult rats. Acute injections of desipramine, in the absence of agonist produced a hypothermic effect in adult but not juvenile rats. In addition, the increased α₂-agonist-induced hypothermic effect following repeated injections of desipramine that is seen in adult rats is not seen in juvenile rats.

An international perspective on pediatric psychopharmacology

The use of pharmacotherapy for children and adolescents with mental disorders varies widely across countries. More than 80% of the world use of stimulant medications occurs in the USA. The use of antidepressants and antipsychotics is many times greater in the USA than in other countries. Factors likely to influence the pediatric use of psychotropic medications are here examined and discussed. Variability in use reflects differences in diagnostic systems, clinical practice guidelines, drug regulation, health services organization, availability and allocation of financial resources, and cultural attitudes towards childhood behavioral and emotional disturbances. Cultural context seems to exert a greater influence on the identification and management of psychiatric disorders than on other areas of medicine. It is currently unknown if the heterogeneity in treatment approaches results in differential clinical outcomes and prognosis. A better understanding of the factors underlying international variability may help clarify the process of diagnosis and treatment selection in child and adolescent psychiatry.

Antidepressant prescribing practices for the treatment of children and adolescents

OBJECTIVE

This study evaluates pediatric antidepressant prescribing practices of Nebraska clinicians.

METHODS

Surveys were sent in July, 2005, to 1,521 prescribing clinicians throughout Nebraska to assess pediatric antidepressant use along with any practice changes following the U.S. Food and Drug Administration (FDA) "black box" warning issued in October, 2004.

RESULTS

Over half (n = 866) of the clinicians responded to the survey, of which 96.8% reported awareness of the FDA "black box" warning. Of the respondents, 76.9% (n = 666) were prescribing antidepressants to children and/or adolescents. Clinicians reported decreased prescribing frequency for both children (15.5%) and adolescents (36.6%), with 36% having increased referrals to specialists. While 31.9% reported seeing patients more frequently upon initiation of antidepressants, only 7.5% reported weekly visits for the first month of treatment, as recommended by the FDA. Over one fifth (21.9%) reported a caregiver or patient had refused antidepressant medication treatment due to the FDA's warning.

CONCLUSION

Clinicians in Nebraska report changes in clinical practice due to the issuance of the FDA "black box" warning, with a decrease in prescribing antidepressants to pediatric patients and an increase in referrals to specialists. Although awareness of the FDA's warning was evident among clinicians and patients, adherence to recommended guidelines was low.

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.

The differential regulation of BDNF and TrkB levels in juvenile rats after four days of escitalopram and desipramine treatment

Major depressive disorder is a major health problem in adults and is now recognized as a substantial problem in children as well. Tricyclic antidepressants, including desipramine (DMI), are no better than placebo in treating childhood and adolescent depression, but are effective in treating adult depression. Several studies have suggested that normal BDNF (brain-derived neurotrophic factor) signaling is necessary for antidepressant drug action. Antidepressant drugs induce several plastic changes in the rodent brain which may be associated with changes in BDNF levels and/or with BDNF function. In the present study we report parallel measurements of BDNF mRNA and protein in the frontal cortex and hippocampus after four days of twice daily treatments with escitalopram, a selective serotonin reuptake inhibitor, and desipramine, a tricyclic antidepressant. Post-natal day 13, 21, 28 and adult rats were used in this study. TrkB (the primary receptor for BDNF) mRNA levels were also examined under the same treatment conditions. BDNF mRNA and protein levels, as well as TrkB mRNA levels, were increased significantly in post-natal day 13 pups after escitalopram treatment as compared to control, but desipramine failed to increase either BDNF or TrkB. The failure of desipramine to increase BDNF and TrkB levels in juvenile rats is consistent with the lack of efficacy of desipramine in children and adolescents. The serotonergic nervous system matures earlier than the noradrenergic system, which may explain why escitalopram, but not desipramine, increases BDNF and TrkB levels.

Childhood and adolescent depression: why do children and adults respond differently to antidepressant drugs?

Childhood and adolescent depression is an increasingly problematic diagnosis for young people due to a lack of effective treatments for this age group. The symptoms of adult depression can be treated effectively with multiple classes of antidepressant drugs which have been developed over the years using animal and human studies. But many of the antidepressants used to treat adult depression cannot be used for pediatric depression because of a lack of efficacy and/or side effects. The reason that children and adolescents respond differently to antidepressant treatment than adults is poorly understood. In order to better understand the etiology of pediatric depression and treatments that are effective for this age group, the differences between adults, children and adolescents needed to be elucidated. Much of the understanding of adult depression has come from studies using adult animals, therefore studies using juvenile animals would likely help us to better understand childhood and adolescent depression. Recent studies have shown both neurochemical and behavioral differences between adult and juvenile animals after antidepressant treatment. Juvenile animals have differences compared to adult animals in the maturation of the serotonergic and noradrenergic systems, and in dose of antidepressant drug needed to achieve similar brain levels. Differences after administration of antidepressant drug have also been reported for adrenergic receptor regulation, a physiologic hypothermic response, as well as behavioral differences in two animal models of depression. The differences between adults and juveniles not only in the human response to antidepressants but also with animals studies warrant a specific distinction between the study of pediatric and adult depression and the manner in which new treatments are pursued.

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.

Fragwürdigkeit eines Gerichtsurteils zur Antidepressiva-Verordnung bei Jugendlichen

Zusammenfassung: Ein Sozialgericht (SG Dresden, S 16 KR 51/06) hat eine beklagte Krankenkasse dazu verurteilt, einer depressiven Jugendlichen stationär verordnetes Fluoxetin für die Zeit der Ausschleichphase weiter zu erstatten, aber die Klage auf generelle Kostenübernahme bei der Patientin für dieses Medikament ansonsten abgewiesen. Dabei wurden dem Gericht vorliegende Unterlagen, insbesondere die Stellungnahme der DGKJP, fehlerhaft rezipiert und das Gericht hat auf die Schaffung einer eigenen Sachkunde, beispielsweise durch ein Sachverständigengutachten, verzichtet. Eine Bezugnahme auf ein Urteil des Bundessozialgerichts zum off-label-Gebrauch zeigt ebenfalls Recherchemängel des erkennenden Gerichts auf und weist allgemein auf eine unklare Umsetzung dieses Urteils hin. Für den behandelnden Arzt resultiert aus dem SG-Urteil ein therapeutisches, ethisches und haftungsrechtliches Dilemma: ein Absetzen der Substanz gefährdet eventuell die Patientin, ist aber im Urteil so vorgesehen. Durch die mittlerweile erfolgte EMEA-Zulassung der Substanz für Minderjährige über 8 Jahren in Europa ist der Fall vielleicht geklärt - nicht jedoch die Implikationen von juristischen Eingriffen in die ärztliche Therapiefreiheit und wissenschaftlich gut begründbare Therapierationalen.

Differential effects of the tricyclic antidepressant desipramine on the density of adrenergic receptors in juvenile and adult rats

Although the tricyclic antidepressants, such as desipramine (DMI), are among the most efficacious treatments for adult depression, they are not effective in treating childhood and adolescent depression. Because the adrenergic nervous system is not fully developed until late adolescence, we hypothesized that the mechanisms regulating receptor density may not yet be mature in young mammals. To test this hypothesis, the effects of DMI treatment on cortical alpha-1-, alpha-2-, and beta-adrenergic receptors were compared in juvenile and adult rats. DMI was delivered either by 4 days of twice daily injections to postnatal day 9 to 13 (4 and 7 mg/kg/day) and adult (20 mg/kg/day) rats, or by 2 weeks of continual drug infusion (osmotic minipumps) to postnatal day 21-35 (15 mg/kg/day) and adult (10 mg/kg/day) rats. These delivery paradigms gave juvenile brain concentrations of DMI similar to those in adult rats. The beta-adrenergic receptor was down-regulated with both treatment paradigms in both juvenile and adult rats. By contrast, in the postnatal day 9 to 13 rats, there was a dose-dependent up-regulation of the alpha-1 in the cortex and alpha-2-adrenergic receptor in the prefrontal cortex, whereas there was no change in density in adult rats. These differences in the alpha-adrenergic receptor regulation after DMI treatment suggest that the lack of efficacy of tricyclic antidepressants in treating childhood depression may be related to immature regulatory mechanisms for these receptors.

Bipolar depression: diagnostic and treatment considerations

Bipolar affective disorder is a recurrent, disabling, and potentially lethal illness that typically begins early in life. Although the disorder is defined by the manic and hypomanic episodes, for most people the depression episodes are the more virulent aspect of the illness. Specifically, the depressive episodes are more numerous, last longer, and are more difficult to treat than the manias, and depression is the principal cause of the illness's increased mortality due to suicide. For people with early-onset depression, predictors of subsequent bipolarity include a family history, psychotic features, and reverse neurovegetative features. Initial episodes of depression are commonly misdiagnosed, which often delays initiation of appropriate therapy and increases the likelihood of treatment with antidepressants alone. Unfortunately, the correct diagnosis is often not made until there has been a treatment-emergent affective switch. There are no treatments specifically approved for bipolar disorder in youth and, among antidepressants, only fluoxetine has received approved. When bipolarity is suspected, treatment with mood stabilizers, both conventional (i.e., lithium, valproate, and carbamazapine) and more recently classified (lamotrigine) and atypical antipsychotics should be prioritized. When antidepressants are indicated in combination with mood stabilizers, first choice options include bupropion and the selective serotonin reuptake inhibitors. Studies of adults indicate that several forms of focused psychotherapy may improve longer term outcomes.

Ethical issues in child psychopharmacology research and practice: emphasis on preschoolers

INTRODUCTION

Psychoactive drug prescription for preschoolers has increased over the past decade and has been a controversial topic for those who prescribe, regulate, and research the use of psychotropics in this population. Children and adolescents are deemed vulnerable populations, at risk of being harmed by unethical or suboptimal practice and research and are in need of special protection. Historically, preschoolers have been therapeutic and research "orphans," excluded from pharmacological studies so that the evidence base for their treatment has to be extrapolated from other ages. Within the past few decades, several ethical principles guiding pediatric psychopharmacological research have been developed. The same principles could effectively guide the treatment of these patients.

CONCLUSION

Further studies are needed to elucidate the safety and effectiveness of psychotropics, and sound ethical guidelines for their involvement in psychiatric research are needed. This article reviews some challenges facing mental health care providers involved in prescribing or researching the use of psychoactive drugs in preschoolers. Some of these challenges are general to medical treatment and research with children, and others are particular to child psychopharmacological treatment and research.

Medikamentöse Therapie der Depression bei Kindern und Jugendlichen

Pharmacological treatment of depression in minors is contested after some published warnings about suicide related behaviour among youths treated with SSRI. This paper examines the last developments concerning antidepressant use in minors, prescrition patterns and evidence of antidepressants used in minors. Reviewing the guidelines and practise parameters, metaanalyses and the TADS-study a recommendation for an evidence based use in minors can only be given for Fluoxetine. Safety aspects should be taken into consideration during the treatment and patients should be kept in close contact to their therapists to observe suicidal related behaviour and adherence.

Research in child and adolescent psychopharmacology: recent accomplishments and new challenges

RATIONALE

Research in pediatric psychopharmacology has expanded considerably in the last 10 years. Still, controversy remains about the effectiveness and safety of commonly used psychotropics and their role in child treatment, thus pointing to the need for more in-depth and targeted investigations.

OBJECTIVES

To review recent accomplishments and current limitations of pediatric psychopharmacology, and discuss approaches to further research.

METHODS

Selective review of the relevant literature and research in progress.

RESULTS

Controlled clinical trials have been conducted in many common psychiatric disorders in children and adolescents, thus providing a basis on which evidence-based treatment guidelines can be constructed. Little innovation has, however, occurred in treatment development and testing. Safety concerns are prominent and have a major influence on clinical practice and drug utilization.

CONCLUSIONS

While a research infrastructure has been successfully built for conducting pediatric clinical trials, important aspects such as long-term treatment effects, optimal sequencing and individualization of interventions, and integration of neuroscience findings into innovative, theory-driven treatment development remain to be addressed.

Appropriate dosing regimens for treating juvenile rats with desipramine for neuropharmacological and behavioral studies

The tricyclic antidepressants, including desipramine (DMI), are no better than placebo in treating childhood and adolescent depression, but are effective in adult depression. Animal studies comparing the effects of DMI in juveniles and adults are complicated by age-related variations in elimination rates. Thus, different dosing regiments are needed to achieve similar brain drug levels in juvenile and adult rats. We compared the half-life of DMI as well as the brain and serum concentrations of DMI and its active metabolite desmethyldesipramine in juvenile and adult rats after various drug administration paradigms. After acute i.p. administration DMI is eliminated from the brain more slowly in postnatal day (PND) 21 and 28 rats as compared to adults. After chronic i.p. administration (for 4-5 days between PND 9 and 28), lower doses of DMI are needed with juvenile rats to obtain the same brain DMI concentrations as adults. By contrast, 2 weeks of continuous drug delivery (minipump) to PND 21-35 and adult rats result in similar brain DMI concentrations. Thus, the pharmacokinetic properties of DMI varies with the age of the animal and dosing of DMI and needs to be carefully adjusted in order to have appropriate brain levels of the drug.

Antidepressants in children and adolescents—changes in utilisation after safety warnings

BACKGROUND

Antidepressants, in particular selective serotonin reuptake inhibitors, are one of the most commonly used classes of psychotropic drug in children and adolescents. Beginning in June 2003, evidence emerged suggesting that antidepressants may increase risk of suicidal behaviour in young people. This evidence was accompanied by national and international guidelines cautioning against use of many antidepressants in young people. This study aimed to assess whether these safety warnings have impacted upon antidepressant utilisation rates.

METHOD

This study was based at a metropolitan health service incorporating children's and adult hospitals. Total service utilisation of antidepressants was extracted from pharmacy software for the period January 2002 to December 2005. Monthly utilisation rates were computed for adults and children's services as defined daily doses (DDD) per occupied bed days. Changes in utilisation over time were examined for children and adults.

RESULTS

There was a significant relationship between time and antidepressant utilisation in children and adolescents, where antidepressant use decreased over time (R = 0.474; t = -3.66; p < 0.01), and in particular, use of SSRIs (R = 0.461; t = -3.52; p < 0.01). In contrast, use of SSRIs (R = 0.587; t = 4.91; p < 0.001) and all antidepressants (R = 0.327; t = 2.35; p < 0.05) increased over time in adults.

CONCLUSIONS

National and international warnings about safety of antidepressants in children and adolescents appear to have influenced local utilisation of these medications in young people but not in adults. Further research is required to determine optimal utilisation rates.

Acute time to response in the Treatment for Adolescents with Depression Study (TADS)

OBJECTIVE

To examine the time to response for both pharmacotherapy and psychotherapy in the Treatment for Adolescents with Depression Study (TADS).

METHOD

Adolescents (N = 439, ages 12 to 17 years) with major depressive disorder were randomized to fluoxetine (FLX), cognitive-behavioral therapy (CBT), their combination (COMB), or pill placebo (PBO). Defining response as very much improved or much improved on the Clinical Global Impression-Improvement Scale (CGI-I), survival analyses using Cox proportional hazards models, and Kaplan-Meier curves were conducted to evaluate time to first response and time to stable response for subjects receiving pharmacotherapy (COMB, FLX, PBO) as well as for subjects receiving CBT (COMB, CBT). Direct comparisons between pharmacotherapy and CBT were not made because of differences in visit schedules.

RESULTS

Based on pharmacotherapist CGI-I scores, COMB and FLX showed faster onset of benefit than PBO on time to response and time to stable response (p < .001), and COMB was faster than FLX on time to stable response (p = .034). The probability of sustained early response was approximately threefold greater for COMB than PBO, twofold greater for FLX than PBO, and 1.5-fold greater for COMB than FLX. On the psychotherapist CGI-I scores, both first response and stable response occurred faster in COMB than CBT (p < .001), with a probability of sustained early response approximately threefold greater for COMB than CBT.

CONCLUSIONS

In the acute treatment of depressed adolescents, FLX and COMB accelerate response relative to PBO, and COMB accelerates response relative to CBT alone.