Antidepressant Prescribing by Pediatricians: A Mixed-Methods Analysis

Antidepressant Prescribing Practices of Pediatric Palliative Care Providers

Background: Mental health diagnoses can co-occur with complex medical illness in pediatric patients. Pediatricians may not feel comfortable with managing psychopharmacology for patients and access to child psychiatrists can be limited. Palliative care (PC) providers follow patients with serious illness longitudinally to address burdensome symptoms that affect quality of life and may be responsible for evaluation and treatment of mental health concerns; however, education in managing psychologic distress for pediatric palliative care (PPC) providers is limited. Objective: This study seeks to describe the antidepressant prescribing practices of PPC providers and describe their level of training and comfort in assessing for anxiety and depression and prescribing psychotropic medications. Methods: An electronic survey approved by the American Academy of Hospice and Palliative Medicine was distributed nationally to PPC providers. Results: A total of 58 providers responded to the survey (response rate 12.3%). Most reported prescribing a variety of antidepressants (79%). Very few used formal assessment tools to screen for depression (7%) or anxiety (16%). Less than a third of providers consulted child psychiatry before prescribing antidepressants (29%). More than half of providers (54.5%) had no formal training in assessment and treatment of anxiety and depression in pediatric patients. Despite this, many providers (70%) reported feeling comfortable in prescribing antidepressants while also endorsing interest in more training for behavioral health evaluation and treatment (82.5%). Conclusions: Limited training in assessing mental health concerns, prescribing, and managing psychopharmacology suggests an opportunity for more targeted education for pediatric PC providers regarding antidepressant prescribing practices.

Pharmacogenetic Factors Influence Escitalopram Pharmacokinetics and Adverse Events in Youth with a Family History of Bipolar Disorder: A Preliminary Study

Introduction: Escitalopram is an effective and generally well-tolerated antidepressant, but children of parents with bipolar disorder (BD) may be at increased risk for adverse events associated with antidepressants, including increased irritability, restlessness, impulsivity, and manic symptoms. This risk may be influenced by polymorphisms in genes encoding cytochrome P450 enzymes (CYP2C19 or CYP2D6), the serotonin transporter (SLC6A4), and the serotonin receptor 2A subtype (HTR2A). We explored whether gene-drug interactions influence the emergence of adverse events in depressed and/or anxious youth with a family history of BD. Materials and Methods: Children and adolescents aged 12-17 years with a first-degree relative with bipolar I disorder were treated with escitalopram and monitored for adverse effects, underwent pharmacogenetic testing, and provided serum escitalopram levels. Emergence of adverse events was determined by study clinicians, and symptoms were tracked using the Treatment-Emergent Activation and Suicidality Assessment Profile (TEASAP) and Pediatric Adverse Events Rating Scale. Clinical Pharmacogenetics Implementation Consortium guidelines were used to determine CYP2C19 and CYP2D6 phenotypes. Results: Slower CYP2C19 metabolizers had greater dose-normalized 24-hour area under the curve (AUC0-24; p = 0.025), trough concentrations (Ctrough; p = 0.013), and elimination half-lives (t1/2; p < 0.001). CYP2D6 phenotype was not significantly associated with any pharmacokinetic parameter. Slower CYP2D6 metabolizers had increased TEASAP akathisia (p = 0.015) scores. HTR2A A/A and A/G genotypes were associated with increased TEASAP "self-injury, suicidality, and harm to others" subscale scores (p = 0.017). Escitalopram maximum concentration, AUC0-24, CYP2C19 phenotype, and SLC6A4 genotype were not associated with adverse events. Conclusions: CYP2C19 phenotype influences escitalopram pharmacokinetics whereas CYP2D6 phenotype does not. Slower CYP2D6 metabolism was associated with increased akathisia, and HTR2A A/A or A/G genotypes were associated with increased risk of self-harm or harm to others. Larger cohorts are needed to identify associations between genetic test results and antidepressant-associated adverse events. Trial Registration: ClinicalTrials.gov identifier: NCT02553161.

Need for Multidimensional and Multidisciplinary Management of Depressed Preadolescents and Adolescents: A Review of Randomized Controlled Trials on Oral Supplementations (Omega-3, Fish Oil, Vitamin D3)

(1) Background: Depression is a serious health problem with a high cost for public administration. Epidemiological studies report that one in five children have a mental disorder and about 50% of mental health problems exacerbate in childhood and adolescence. Moreover, the antidepressant efficacy in children and adolescents is poorly demonstrated and can cause severe behavioral adverse events such as suicidal ideation. (2) Methods: This systematic literature review examined oral supplementations (Omega-3, fish oil, Vitamin D₃) to treat depressed children, preadolescents, and adolescents. MEDLINE, Scopus, Embase, and PsycInfo were searched for articles published in the last five years. Six studies met the eligibility criteria. The inclusion criteria encompassed children, preadolescents, and adolescents, a diagnosis of depression, and an intervention of oral supplementations such as Omega-3, fish oil, and Vitamin D₃. (3) Results: Most of the studies demonstrated that dietary intervention provides positive outcomes in terms of depression symptoms. (4) Conclusions: Overall, the results demonstrate a positive effect for oral supplementation suggesting an increase intake of Omega-3, fish oil, and Vitamin D₃. However, only a few studies assess the effectiveness of diet recommendations, as a monotherapy or combined treatment, for the management of depression at developmental ages. Thus, there is still a need to further investigate these aspects and to look more specifically at adolescents and preadolescents.

Anxiety and Depression Treatment in Primary Care Pediatrics

BACKGROUND AND OBJECTIVES

Primary care pediatricians (PCP) are often called on to manage child and adolescent anxiety and depression. The objective of this study was to describe PCP care practices around prescription of selective serotonin reuptake inhibitors (SSRI) for patients with anxiety and/or depression by using medical record review.

METHODS

We identified 1685 patients who had at least 1 visit with a diagnosis of anxiety and/or depression in a large primary care network and were prescribed an SSRI by a network PCP. We randomly selected 110 for chart review. We reviewed the visit when the SSRI was first prescribed (medication visit), immediately previous visit, and immediately subsequent visit. We abstracted rationale for prescribing medication, subspecialist involvement, referral for psychotherapy, and medication monitoring practices.

RESULTS

At the medication visit, in 82% (n = 90) of cases, PCPs documented reasons for starting an SSRI, most commonly clinical change (57%, n = 63). Thirty percent (n = 33) of patients had documented involvement of developmental-behavioral pediatrics or psychiatry subspecialists at 1 of the 3 visits reviewed. Thirty-three percent (n = 37) were referred to unspecified psychotherapy; 4% (n = 4) were referred specifically for cognitive behavioral therapy. Of 69 patients with a subsequent visit, 48% (n = 33) had documentation of monitoring for side effects.

CONCLUSIONS

When prescribing SSRIs for children with anxiety and/or depression, PCPs in this network documented appropriate indications for starting medication and prescribed without subspecialist involvement. Continuing medical education for PCPs who care for children with these conditions should include information about evidence-based psychotherapy and strategies for monitoring potential side effects.

Medical decision-making for adolescents with depression: A bibliometric study and visualization analysis via CiteSpace

This study focussed on evaluating the status of recent research on medical decision-making for adolescents with depression and identifying research hotspots and frontiers via CiteSpace. We extracted studies that were concerned with medical decision-making for adolescents with depression from the Web of Science Core Collection (WoSCC), covering the period from 1 January 1999 to 20 September 2022. We used CiteSpace to generate online maps of worldwide cooperation among countries, institutions, and authors. Hotspots and frontiers were systematically summarized. A total of 368 papers related to medical decision-making for adolescents with depression were obtained from WoSCC. The most prolific author was Nick Midgley (seven papers). The United States and University College London were the leading country and institution in this research area, with 177 and 17 papers, respectively. Countries, institutions, and authors all actively collaborated. Main recent research trends include the preference or attitude towards medical treatment in adolescents with depression; approaches for adolescents with depression to seeking medical help; and the key role of parent, family, and primary care in medical decision-making for adolescents. Thus, further attention should be paid to determining how to promote the role of parents, families, and primary care in the decision-making process and create appropriate online help-seeking tools and decision aids to facilitate shared decision-making in the future.

Adverse Effects of Antidepressant Medications and their Management in Children and Adolescents

INTRODUCTION

Selective serotonin reuptake inhibitors (SSRIs) and, to a lesser extent, serotonin-norepinephrine reuptake inhibitors (SNRIs) are the cornerstone of pharmacotherapy for children and adolescents with anxiety and depressive disorders. These medications alleviate symptoms and restore function for many youths; however, they are associated with a distinct adverse effect profile, and their tolerability may complicate treatment or lead to discontinuation. Yet, SSRI/SNRI tolerability has received limited attention in the pediatric literature.

METHODS

This review examines the early- (e.g., activation, gastrointestinal symptoms, sedation) and late-emerging (e.g., weight gain) adverse effects of SSRIs and some SNRIs in pediatric patients.

RESULTS

We provide a framework for discussing SSRI/SNRI tolerability with patients and their families and describe the pharmacologic basis, course, and predictors of adverse events in youth. Strategies to address specific tolerability concerns are presented. For selected adverse events, using posterior simulation of mean differences over time, we describe their course based on Physical Symptom Checklist measures in a prospective, randomized trial of anxious youth aged 7-17 years who were treated with sertraline (n = 139) or placebo (n = 76) for 12 weeks in the Child/Adolescent Anxiety Multimodal Study (CAMS).

MAIN RESULTS

In CAMS, the relative severity/burden of total physical symptoms (p < 0.001), insomnia (p = 0.001), restlessness (p < 0.001), nausea (p = 0.002), abdominal pain (p < 0.001), and dry mouth (p = 0.024) decreased from baseline over 12 weeks of sertraline treatment, raising the possibility that these symptoms are transient. No significant changes were observed for sweating (p = 0.103), constipation (p = 0.241), or diarrhea (p = 0.489). Finally, we review the antidepressant withdrawal syndrome in children and adolescents and provide guidance for SSRI discontinuation, using pediatric pharmacokinetic models of escitalopram and sertraline-two of the most used SSRIs in youth.

CONCLUSION

SSRI/SNRIs are associated with both early-emerging (often transient) and late-emerging adverse effects in youth. Pharmacokinetically-informed appraoches may address some adverse effects and inform SSRI/SNRI discontinuation strategies.

Pharmacogenomic Profiling of Pediatric Patients on Psychotropic Medications in an Emergency Department

OBJECTIVE

The aim of the study was to evaluate the ability of a combinatorial pharmacogenomic test to predict medication blood levels and relative clinical improvements in a selected pediatric population.

METHODS

This study enrolled patients between ages 3 to 18 years who presented to a pediatric emergency department with acute psychiatric, behavioral, or mental health crisis and/or concerns, and had previously been prescribed psychotropic medications. Patients received combinatorial pharmacogenomic testing with medications categorized according to gene-drug interactions (GDIs); medications with a GDI were considered "incongruent," and medications without a GDI were considered "congruent." Blood levels for escitalopram, fluoxetine, aripiprazole, and clonidine were evaluated according to level of GDI. Relative clinical improvements in response to the prescribed psychotropic medications were measured using a parent-rated Clinical Global Impression of Improvement (CGI-I) assessment, where lower scores corresponded with greater improvement.

RESULTS

Of the 100 patients enrolled, 73% reported taking ≥1 incongruent medication. There was no significant difference in CGI-I scores between patients prescribed congruent versus incongruent medications (3.37 vs 3.68, P = 0.343). Among patients who presented for depression or suicidal ideation, those prescribed congruent medications had significantly lower CGI-I scores compared with those taking incongruent medications ( P = 0.036 for depression, P = 0.018 for suicidal ideation). There was a significant association between medication GDI and blood levels for aripiprazole (n = 15, P = 0.01) and escitalopram (n = 10, P = 0.01).

CONCLUSIONS

Our preliminary findings suggest that combinatorial pharmacogenomic testing can predict medication blood levels and relative outcomes based on medication congruency in children presenting to an emergency department with acute psychiatric/behavioral crises. Additional studies will be needed to confirm these findings.

Assessment of Oncology Advanced Practice Professional Willingness to Participate in Medical Aid in Dying

IMPORTANCE

In 2021, New Mexico passed legislation allowing nurse practitioners and physician assistants (referred to herein as advanced practice professionals [APPs]) to prescribe medications for medical aid in dying (MAID). Other US states with existing MAID laws (eg, Washington) are also considering expanding MAID prescribing authority to APPs. There is a lack of research exploring APP knowledge of, willingness to, and comfort with acting as a prescribing or consulting clinician for MAID.

OBJECTIVE

To assess perspectives of oncology APPs regarding MAID, including their willingness to prescribe and/or consult for MAID and factors associated with willingness.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional, self-report survey study used data collected from APPs working at a comprehensive cancer center in Washington State in fall 2021.

MAIN OUTCOMES AND MEASURES

The primary survey question was whether APPs would be willing to participate in death with dignity, the term used for MAID in Washington. Survey questions evaluated how influential specific factors were on APP views on MAID as well as respondents' knowledge of and comfort with aspects of the MAID process.

RESULTS

Of 167 eligible APPs, 77 (46.1%) responded to the survey. Most respondents (68 [88.3%]) reported their race and ethnicity as White; 72 (93.5%) identified as a woman. Medical oncology (28 [36.4%]) was the most common field of practice, and 21 respondents (27.3%) reported having practiced as an APP for 6 to 10 years. Of all respondents, 61 (79.2%) reported having at least 1 patient who inquired about MAID; depending on the question, less than a third of respondents (5.0%-27.0%) endorsed feeling knowledgeable or very knowledgeable about any aspect of the MAID process. In this study, 39 APPs (50.6%) endorsed being willing to participate in MAID either as a consulting or prescribing clinician, whereas 31 (40.3%) were uncertain of whether they would participate. Willingness to participate was associated with having had more patients pursue MAID (33 of the 39 willing participants [84.6%] vs 15 of the 31 unsure participants [48.4%] reported having 1 or more patients pursue MAID). Higher knowledge and comfort scores were both significantly associated with increased odds of being willing to participate (odds ratio, 1.14 per 1-point score increase [95% CI, 1.03-1.27]; P = .01) vs unsure (1.18 [95% CI, 1.07-1.30; P = .001).

CONCLUSIONS AND RELEVANCE

The results of this survey study suggest that oncology APPs may require preparation for the addition of MAID to their scope of practice. This study also raises questions for future research regarding support for APPs who may be considering participation in MAID but question their role or want physician involvement.

A Double-Blind Randomized Trial to Investigate Mechanisms of Antidepressant-Related Dysfunctional Arousal in Depressed or Anxious Youth at Familial Risk for Bipolar Disorder

Antidepressants are standardly used to treat moderate to severe symptoms of depression and/or anxiety in youth but may also be associated with rare but serious psychiatric adverse events such as irritability, agitation, aggression, or suicidal ideation. Adverse events are especially common in youth with a family history of bipolar disorder (BD) who are at heightened risk for dysfunction in neurobiological systems that regulate emotion and arousal. To further understand this phenomenon, this study will examine (a) baseline risk factors associated with dysfunctional arousal in a sample of youth at high-risk for BD treated with or without an antidepressant, (b) whether antidepressant-related changes in arousal are mediated by changes in prefrontal-limbic circuitry, and (c) whether pharmacogenetic factors influence antidepressant-related changes in arousal. High-risk youth (aged 12-17 years with moderate to severe depressive and/or anxiety symptoms and at least one first-degree relative with bipolar I disorder) will be randomized to receive psychotherapy plus escitalopram or psychotherapy plus placebo. Neuroimaging and behavioral measures of arousal will be collected prior to randomization and at 4 weeks. Samples for pharmacogenetic analysis (serum escitalopram concentration, CYP2C19 metabolizer phenotype, and HTR2A and SLC6A4 genotypes) will be collected at 8 weeks. Youth will be followed for up to 16 weeks to assess change in arousal measures.

Acute neurofunctional effects of escitalopram during emotional processing in pediatric anxiety: a double-blind, placebo-controlled trial

Anxiety disorders are the most common mental disorders in adolescents. However, only 50% of pediatric patients with anxiety disorders respond to the first-line pharmacologic treatments-selective serotonin reuptake inhibitors (SSRIs). Thus, identifying the neurofunctional targets of SSRIs and finding pretreatment or early-treatment neurofunctional markers of SSRI treatment response in this population is clinically important. We acquired pretreatment and early-treatment (2 weeks into treatment) functional magnetic resonance imaging during a continuous processing task with emotional and neutral distractors in adolescents with generalized anxiety disorder (GAD, N = 36) randomized to 8 weeks of double-blind escitalopram or placebo. Generalized psychophysiological interaction analysis was conducted to examine the functional connectivity of the amygdala while patients viewed emotional pictures. Full-factorial analysis was used to investigate the treatment effect of escitalopram on amygdala connectivity. Correlation analyses were performed to explore whether pretreatment and early (week 2) treatment-related connectivity were associated with treatment response (improvement in anxiety) at week 8. Compared to placebo, escitalopram enhanced emotional processing speed and enhanced negative right amygdala-bilateral ventromedial prefrontal cortex (vmPFC) and positive left amygdala-right angular gyrus connectivity during emotion processing. Baseline amygdala-vmPFC connectivity and escitalopram-induced increased amygdala-angular gyrus connectivity at week 2 predicted the magnitude of subsequent improvement in anxiety symptoms. These findings suggest that amygdala connectivity to hubs of the default mode network represents a target of acute SSRI treatment. Furthermore, pretreatment and early-treatment amygdala connectivity could serve as biomarkers of SSRI treatment response in adolescents with GAD. The trial registration for the study is ClinicalTrials.gov Identifier: NCT02818751.

Pediatric Psychopharmacology for Depressive and Anxiety Disorders

Anxiety and depressive disorders are the most common psychiatric illnesses among children and adolescents. These disorders are associated with impairments in social, family, and educational functioning. This article summarizes the evidence base for psychopharmacologic interventions; the developmental pharmacology of selective serotonin reuptake inhibitors (SSRIs) and serotonin norepinephrine reuptake inhibitors (SNRIs); and pharmacokinetic and pharmacodynamic differences between youths and adults that call for differences in dosage and affect response and tolerability. The authors also review the efficacy and tolerability of SSRIs and SNRIs in children and adolescents with depressive and anxiety disorder diagnoses, as well as data related to duration of therapy and SSRI/SNRI discontinuation in this population. Taken together, the current evidence suggests that SSRIs are the first-line psychopharmacologic intervention for youths with depressive and anxiety disorders, with SNRIs having a more limited role. These medications are safe and well tolerated, although emerging data and developmental pharmacologic concepts may help clinicians to choose from available SSRIs and to improve the efficacy and tolerability of these medications in children and adolescents.

Medication Management of Anxiety and Depression by Primary Care Pediatrics Providers: A Retrospective Electronic Health Record Study

OBJECTIVES

To describe medication management of children diagnosed with anxiety and/or depression by primary care providers within a primary care network.

STUDY DESIGN/METHODS

We performed a retrospective cross-sectional analysis of electronic health record (EHR) structured data from all children seen at least twice in a 4-year observation period within a network of primary care clinics in Northern California. For children who had visit diagnoses of anxiety, depression, anxiety+depression or symptoms characteristic of these conditions, we analyzed the rates and types of medications prescribed. A logistic regression model considered patient variables for the combined sample.

RESULTS

Of all patients 6-18 years old (N = 59,484), 4.4% (n = 2,635) had a diagnosis of anxiety only, 2.4% (n = 1,433) depression only, and 1.2% (n = 737) both anxiety and depression (anxiety + depression); 18% of children with anxiety and/or depression had comorbid ADHD. A total of 15.0% with anxiety only (n = 357), 20.5% with depression only (n = 285), and 47.4% with anxiety+depression (n=343) were prescribed a psychoactive non-stimulant medication. For anxiety and depression only, the top three medications prescribed were sertraline, fluoxetine, and citalopram. For anxiety + depression, the top three medications prescribed were citalopram, sertraline, and escitalopram. Frequently prescribed medications also included benzodiazepines. Logistic regression modeling showed that the depression only and anxety + depression categories had increased likelihood of medication prescription. Older age and mental health comorbidities were independently associated with increased likelihood of medication prescription.

CONCLUSIONS

In this network, ~8% of children carried a diagnosis of anxiety and/or depression. Medication choices generally aligned with current recommendations with the exception of use of benzodiazepines.

Pharmacogenetically Guided Escitalopram Treatment for Pediatric Anxiety Disorders: Protocol for a Double-Blind Randomized Trial

Current pharmacologic treatments for pediatric anxiety disorders (e.g., selective serotonin reuptake inhibitors (SSRIs)) frequently use "one size fits all" dosing strategies based on average responses in clinical trials. However, for some SSRIs, including escitalopram, variation in CYP2C19 activity produces substantial variation in medication exposure (i.e., blood medication concentrations). This raises an important question: would refining current SSRI dosing strategies based on CYP2C19 phenotypes increase response and reduce side effect burden? To answer this question, we designed a randomized, double-blind trial of adolescents 12-17 years of age with generalized, separation, and/or social anxiety disorders (N = 132). Patients are randomized (1:1) to standard escitalopram dosing or dosing based on validated CYP2C19 phenotypes for escitalopram metabolism. Using this approach, we will determine whether pharmacogenetically-guided treatment-compared to standard dosing-produces faster and greater reduction in anxiety symptoms (i.e., response) and improves tolerability (e.g., decreased risk of treatment-related activation and weight gain). Secondarily, we will examine pharmacodynamic variants associated with treatment outcomes, thus enhancing clinicians' ability to predict response and tolerability. Ultimately, developing a strategy to optimize dosing for individual patients could accelerate response while decreasing side effects-an immediate benefit to patients and their families. ClinicalTrials.gov Identifier: NCT04623099.

Primary care pediatrician perceptions towards mental health within the primary care setting

BACKGROUND

Mental health (MH) conditions are highly prevalent, yet only marginal portions of children receive adequate services. Access to specialized mental healthcare is limited and, consequently, pediatricians remain the source of management and care of children with MH disorders. Despite this, research suggests that pediatricians report lack of access to training and support regarding MH care of youth, leading to discomfort with managing the population they are asked to treat. An additional barrier to care that has less research is perceptions regarding MH disorders among pediatricians. This scoping review aims to describe the state of science regarding perceptions and possible stigma towards MH in pediatric primary care.

METHODS

PsychInfo, PubMed Medline, Ovid Medline, CINAHL, and Embase were searched with terms related to stigma, pediatricians, and MH disorders. New research articles were included after review, which addressed stigma in pediatricians treating youth with MH disorders.

RESULTS

Our initial search produced 457 titles, with 23 selected for full-text review, and 8 meeting inclusion criteria, N = 1571 pediatricians.

CONCLUSIONS

While a limited number of studies focus on physician-based perceptions/stigma, and even less data on pediatrician stigma towards MH, more studies are needed to explore how this impacts patient care.

IMPACT

In this scoping review, we sought to shed light on the limitations regarding MH care access, especially with the increasing need for care and not enough MH specialists, adding to an already tremendous burden pediatric primary care providers face daily. We also reviewed barriers to said care within pediatric primary care, including the potential for physician stigma towards MH diagnosis, treatment, and management. This review adds a concise summary of the current limited studies on stigma towards MH within primary care pediatricians and the importance of continued research into how perception and stigma affect patient care. This material is an original project and has not been previously published. This work is not submitted for publication or consideration elsewhere.

Who is prescribing psychotropic medications in a public developmental-behavioural clinical service and how often?

AIM

Psychotropic prescribing by paediatricians is increasingly common, and there is considerable variation in care provided. The aims of this study were to examine current rates of psychotropic prescribing in the developmental-behavioural outpatient clinics at the Royal Children's Hospital's Centre for Community Child Health, and to compare rates between paediatric consultants and advanced trainees.

METHODS

Data were extracted for appointment encounters from electronic medical records across 12 months in 2017. Patient demographics, provider and medication order data were analysed using Excel and STATA to calculate logistic regression, standard deviation, percentages and means.

RESULTS

From 5069 encounters, there were 847 (16.7%) that included psychotropic prescribing. Advanced trainees prescribed psychotropic medications in only 4.4% of their encounters compared with consultants who prescribed these medications in 23% of encounters (P < 0.001). Stimulants were the most commonly prescribed psychotropic medication (62%), either alone (86.3%) or in combination (13.7%).

CONCLUSIONS

Psychotropic prescribing rates were lower than expected. Advanced trainees may need more experience in psychotropic prescribing.

CYP2C19-Guided Escitalopram and Sertraline Dosing in Pediatric Patients: A Pharmacokinetic Modeling Study

Objective: Cytochrome P4502C19 (CYP2C19) is a highly polymorphic gene that encodes an enzyme that metabolizes escitalopram and sertraline, two selective serotonin reuptake inhibitors (SSRIs) that are FDA approved for pediatric use and commonly used to treat anxiety and depressive disorders in youth. Using pharmacokinetic (PK) models in adolescents, we sought to (1) model SSRI dosing across CYP2C19 phenotypes to compare SSRI exposure (area under curve, AUC) and maximum concentration (Cmax), (2) evaluate the impact of b.i.d. dosing (in rapid metabolizers [RM] and ultrarapid metabolizers [UM]) on SSRI exposure and Cmax, and (3) determine pharmacogenomically-informed dosing strategies to provide similar exposure across CYP2C19 phenotypes in adolescents. Methods: Using PK parameters in CYP2C19 phenotype groups and previously reported pediatric PK data for escitalopram and sertraline, we modeled exposure (AUC0-24) and Cmax and determined CYP2C19-guided dosing strategies. Results: Compared with normal CYP2C19 metabolizers treated with either escitalopram or sertraline, Cmax and AUC0-24 were higher in slower metabolizers and lower in patients with increased CYP2C19 activity, although the magnitude of these differences was more pronounced for escitalopram than for sertraline. For escitalopram, poor metabolizers (PMs) require 10 mg/day and UMs require 30 mg/day to achieve an exposure that is equivalent to 20 mg/day in a normal metabolizer (NM). For sertraline, to achieve AUC0-24 and Cmax similar to NMs receiving 150 mg/day, PMs require 100 mg/day, whereas a dose of 200 mg/day was required in rapid and UMs. For UMs, b.i.d. escitalopram dosing was necessary to achieve comparable trough levels and exposure to NMs. Conclusions: This simulation study raises the possibility that achieving similar escitalopram and sertraline plasma concentrations could require dose adjustments in CYP2C19 poor metabolizers and UMs, although the magnitude of these differences were more pronounced for escitalopram than for sertraline. However, prospective trials of pharmacogenomically guided dosing in the pediatric population are needed to extend the findings of these modeling studies.

Pharmacogenomic Testing in Child and Adolescent Psychiatry: An Evidence-Based Review

Significant advances have been made in the application of pharmacogenomic testing for the treatment of patients with psychiatric disorders. Over the past decade, a number of studies have evaluated the utility of pharmacogenomic testing in pediatric patients with psychiatric disorders. The evidence base for pharmacogenomic testing in youth with depressive and anxiety disorders as well as attention/deficit hyperactivity disorder (ADHD) is reviewed in this article. General pharmacogenomic principles are summarized and functional polymorphisms in P450 enzymes (and associated metabolizer phenotypes), the serotonin transporter promoter polymorphisms, serotonin 2A receptor genes (e.g., HT2AR) and catecholamine pathway genes (e.g., COMT) are reviewed. These commonly tested pharmacogenomic markers are discussed with regard to studies of drug levels, efficacy and side effects. The translation of pharmacogenomics to individualized/precision medicine in pediatric patients with ADHD, anxiety and depressive disorders has accelerated; however, its application remains challenging given that there are numerous divergent pathways between medication/medication dose and clinical response and side effects. Nonetheless, by leveraging variations in individual genes that may be relevant to medication metabolism or medication target engagement, pharmacogenomic testing may have a role in predicting treatment response, side effects and medication selection in youth with ADHD, depressive and anxiety disorders.

Antidepressant-Induced Activation in Children and Adolescents: Risk, Recognition and Management

The tolerability of antidepressants is poorly characterized in children and adolescents with depressive and anxiety disorders. Among adverse events that affect the tolerability of antidepressants in youth is activation, a cluster of symptoms that represent a hyperarousal event characterized by impulsivity, restlessness, and/or insomnia. This cluster of symptoms was first identified as a side effect of selective serotonin and selective serotonin norepinephrine inhibitors (SSRIs and SSNRIs) in the early 1990s; however, activation remains poorly characterized in terms of prevalence, risk factors, and pathophysiology. This article describes the pathophysiology of antidepressant-related activation, predictors of activation and its clinical management in youth with depressive and anxiety disorders who are treated with antidepressant medications.