Behavioral Interventions for Irritability in Children and Adolescents

Irritability is a common and impairing problem in children and adolescents that can be viewed as a dimension of psychopathology, as well as a core or co-occurring symptom in many childhood disorders. Two forms of interventions for irritability, parent management training (PMT) and cognitive-behavioral therapy (CBT), share common behavioral principles and social information-processing theoretical underpinnings. PMT aims to ameliorate aversive patterns of family interaction that produce the antecedents and consequences that maintain a child’s noncompliance and aggression. During CBT, children learn to regulate frustration and improve social problem-solving skills to reduce the frequency and intensity of anger outbursts and aggressive behavior. Dialectical behavior therapy (DBT) combines training in behavioral skills for reducing interpersonal conflicts with mindfulness and acceptance techniques for emotion regulation. Treatment studies of these approaches in children with various forms of behavioral and emotion dysregulation are reviewed and implications for children with disruptive mood dysregulation disorder are discussed.

Behavioral and Psychophysiological Investigations of Irritability

A better understanding of neurocognitive mechanisms underlying irritability has the potential to inform treatments and improve quality of life for the children for whom this symptom is severe and persistent. This chapter examines the existing behavioral and psychophysiological investigations into irritability-related mechanisms in youth. Together, these measures provide insight into the cognitive and socioemotional abilities of youth with irritability. Existing research explores three domains: executive functioning, reward processing, and responses to emotional stimuli. Although deficits have been observed in each domain, the strongest evidence exists for atypical frustrative nonreward responses (i.e., when an expected reward is not received), face emotion identification deficits, and increased attention toward threatening faces. We discuss limitations to the existing literature and propose avenues for future research, including exploring cognitive-emotion interactions, using dimensional measures of irritability, and examining whether deficits are unique to irritability or related to co-occurring symptoms.

On Being Mad, Sad, and Very Young

Up to 85% of young children in industrialized societies have tantrums. Anger peaks early in these outbursts, then declines. Distress/sadness behaviors remain relatively constant across the tantrum, but comfort-seeking accelerates toward the end, perhaps disinhibited by the anger decline. Distress always outlasts anger and can elicit parental comfort-giving, thus repairing social bonds broken by the child’s anger. Developmentally, tantrums become common around 18 months, perhaps reflecting the emergence of a neurodevelopmental program that anticipates struggles around weaning and independent mobility, as in contemporary forager/village cultures. Such a program might involve left hemisphere anger generation and right hemisphere distress. Mean tantrum frequencies range from 1–9/week, decreasing with age. Tantrum prevalence drops below 50% around 5–6 years. Tantrums may lengthen with age, perhaps morphing into adult anger episodes with a variable residue of distress. Tantrum severity increases in many medical and psychopathological conditions; roughly half of child psychiatry admissions involve severe tantrums.

Irritability in Pediatric Psychopathology

Irritability is a common presenting concern in youth with autism spectrum disorder (ASD). This chapter provides an overview of research on irritability in ASD, including informative findings from the related fields of temperament and emotion regulation. The developmental course is described, highlighting irritability as one of the earliest phenotypic characteristics in ASD. ASD-related characteristics that may predispose youth with ASD to experience high or chronic irritability are considered, in addition to conceptualizations of irritability in ASD as resulting from a co-occurring psychiatric disorder. Common approaches to assessment, psychosocial treatment, and pharmacologic management of irritability are summarized. Finally, gaps in our understanding of irritability in ASD are highlighted and promising directions for future research are provided.

Pharmacological Treatment of Pediatric Irritability

Irritability is among the most common and impairing mental health issues affecting children today, with research showing that the consequences of irritability last into adulthood. Advancing how we treat irritability, including with medications, thus should be a top public health priority, germane to all those working with children and adults, and not just restricted to mental health settings. In this chapter, the authors review general principles of using medication to treat irritability in children. Then, they provide the latest information about the pharmacological treatment of irritability. In doing so, they draw on published studies of disorders involving irritability, including bipolar disorder (BD), unipolar major depressive disorder (MDD), attention deficit/hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), intermittent explosive disorder (IED), and autism spectrum disorder (ASD). While there is ample room for innovative ways to assess and treat irritability in children, at present, clinicians should carefully assess the child, develop a working hypothesis for what disorder(s) involving irritability are present, use evidence-based treatments to address those problems, and then reassess for improvement, worsening, side effects, or how these longitudinal data shapes working diagnoses.

Irritability and Disruptive Behavior Disorders

Chronic irritability has recently been established as an affective component of pediatric disruptive behavior disorders. In this chapter, the authors review its relationship to disruptive behaviors, with a particular focus on aggression and major disruptive behavior disorders. Defined as a decreased threshold to respond to provocation with anger and temper outbursts, chronic irritability has long been considered an important feature of emotionally driven, disruptive behavior. Recent investigations into irritability suggest that it has important prognostic value for disruptive youth. Furthermore, investigations of disruptive behaviors have informed work on irritability, yielding promising leads for understanding its pathophysiology and treatment.

Genetics of Pediatric Irritability

This chapter provides an overview of behavioral and molecular genetics of pediatric irritability. Literature searches using PubMed and PsycInfo databases yielded 37 relevant animal and human studies on irritability. Studies of rodent and primate models initially suggested a genetic etiology for the trait and influenced selection of candidate genes for study in human studies. Behavioral genetic studies of irritability suggest that pediatric irritability is likely influenced by additive genetic and nonshared unique environmental factors, with little to no influence of dominant genetic or shared family environmental factors. Molecular genetic studies have been largely limited to candidate genes with a few emerging genome-wide association studies (GWAS). Results from the candidate gene literature on irritability are inconclusive, and GWAS in clinical populations has yielded limited findings. Future genetic studies of irritability would benefit from the use of appropriate phenotypic measures, adequate sample sizes, and multimethod and longitudinal approaches.

Measurement of Irritability in Children and Adolescents

While irritability is a symptom included in multiple DSM psychiatric illnesses, it has remained an ill-defined and underresearched phenomenon until relatively recently. There have been multiple attempts made to measure irritability in childhood and adolescence. The purpose of this chapter is to provide an overview of the various approaches used in the measurement and empirical study of pediatric irritability. In this chapter, the authors describe attempts at measuring irritability with standardized diagnostic interviews, and then discuss how variable- and person-centered statistical models have shaped these earliest measures. The authors discuss models and measures that are emerging, including the construct of disruptive mood dysregulation disorder as well as measures such as the Affective Reactivity Index and the Child Behavior Checklist-Dysregulation Profile. They conclude that, given the transdiagnostic nature of irritability, efforts should be made to understand the relationship of irritability to various forms of developmental psychopathology using multiple methods.

Introduction

Pediatric irritability is one of the most common reasons for mental health evaluation and treatment. Irritability is transdiagnostic; while it is the hallmark symptom of disruptive mood dysregulation disorder, a new diagnosis in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), it also appears in the diagnostic criteria for several mood, anxiety, and behavioral disorders and is a common correlate in others. The past 15 years have witnessed a rise in clinical neuroscience studies of pediatric irritability, resulting in significant advances in our understanding of its neural, genetic, psychophysiological, and behavioral correlates. These advances are detailed in the chapters in this volume. There is a particular focus on the implications of these findings for assessment and treatment of irritable youth, along with suggestions for further research.

Irritability in Mood and Anxiety Disorders

Irritability is common in children and adolescents presenting with mood and anxiety disorders and was recently introduced in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) as a diagnostic category under the name of disruptive mood dysregulation disorder (DMDD). The aim of this chapter is to describe the distinct phenomenology, epidemiology, and correlates of irritability in the context of bipolar disorder, DMDD, depression, and anxiety disorders. The course of irritability is episodic in bipolar disorder and depression and is commonly accompanied by elated and depressed mood, respectively. In contrast, the irritability seen in DMDD is chronic and recurrent. In anxiety disorders, the experience of irritability is usually related to the presence of the feared situation. Regardless of these differences, irritability seems to be associated with higher rates of comorbidity and greater functional impairment and may need attention in its own right.