Attention Deficit Hyperactivity Disorder in Autism Spectrum Disorder

This chapter will review the available evidence on individuals with co-occurring diagnoses of autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD). This chapter contends that children diagnosed with both disorders (ASD+ADHD) are a subset of the ASD population that is at risk for delayed recognition of their ASD diagnosis, poor treatment response, and poorer functional outcomes compared to those with ASD without ADHD. Specifically, the chapter highlights the best estimates of the prevalence of the comorbidity, the developmental trajectory of people with co-occurring ASD and ADHD, how ADHD symptoms change across development, overlapping genetic and neurobiological risk factors, psychometrics of ADHD diagnostic instruments in an ASD population, neuropsychological and functional impairments associated with co-occurring ASD and ADHD, and the current state of evidence-based treatment for both ASD and ADHD symptoms. Finally, the chapter discusses fruitful avenues of research for improving understanding of this high-risk comorbidity so that mechanism-to-treatment pathways for ADHD in children with ASD can be better developed.

Oppositional Defiant Disorder and Related Disruptive Behaviors in Autism Spectrum Disorder

The Diagnostic and Statistical Manual of Mental Disorders, fifth edition characterizes oppositional defiant disorder (ODD) as reflecting pervasive patterns of irritable mood, defiant behavior, and/or vindictiveness. Youth with autism spectrum disorder (ASD) exhibit high rates of disruptive behaviors commonly associated with ODD, such as noncompliance, irritability, temper tantrums, and mood dysregulation. This chapter reviews the presentation of ODD in individuals with ASD, including current prevalence estimates, proposed etiology, validated assessment methods, and emerging best practices designed to treat challenging behaviors. Although there is a robust literature describing assessment and treatment procedures for disruptive behaviors in individuals with ASD, conceptualizing these hallmark behaviors within the framework of ODD is relatively novel and not without controversy. Discussion thus includes challenges around the applicability of the diagnostic criteria in this population and future research directions that may provide clarity on this issue.

Synthesis

Recent research and clinical attention devoted to co-occurring psychiatric conditions within autism spectrum disorder (ASD) has led to significant advances in the understanding of and ability to assess and treat co-occurring problems effectively. This chapter summarizes those advances while also highlighting the substantial gaps that remain in the understanding of co-occurring problems in people with ASD. The chapter provides recommendations for future research directions in the areas of etiology, developmental course, assessment, and treatment. It also offers suggestions for improving the representativeness of research participants and strengthening community–academic partnerships in this important field of study.

A Model for Addressing Crisis Behavior in Youth With Autism Spectrum Disorder Within a Functional and Contextual Framework

This chapter provides a model that extends the current resources available for crisis behavior assessment and intervention for youth with autism spectrum disorder (ASD) and co-occurring psychiatric conditions who are in crisis stabilization settings. Visual diagrams and intervention materials incorporated into this chapter illustrate the use of both preventative and responsive behavior management strategies that can be implemented in a time of crisis to stabilize and treat the psychiatric patient with ASD. The chapter begins with a review of a contextual method for evaluating and understanding the function of the presenting crisis behavior by considering the multiple issues that can underlie the crisis presentation. Working from this contextual model, the chapter then provides a blueprint for implementing intervention strategies to address crisis behaviors. This includes a table illustrating key elements to consider when developing a behavior intervention plan for dissemination and generalization.

Co-Occurring Mood Problems in Autism Spectrum Disorder

Recent evidence suggests that individuals with autism spectrum disorder (ASD) experience depression at rates approximately four times greater than the general population. Co-occurring mood problems, including depressive and bipolar disorders, are associated with negative outcomes such as lower quality of life, increased adaptive behavior impairments, and greater service use. This chapter discusses what is known about the presentation of unipolar and bipolar depression in people with ASD and describes challenges to establishing sound prevalence estimates of mood disorders in ASD as they relate to methodological design issues and diagnostic assessment practices. It also provides an overview of potential vulnerability factors in the development of depression in this population; these areas of vulnerability include characteristics such as chronological age, cognitive ability, and ASD symptom severity, as well as those individual differences that may represent more direct mechanisms, for example, maladaptive coping styles, attentional biases, social reward profiles, and predisposition to rumination. The current research on interventions specifically designed to treat mood in people with ASD is very limited. However, promising treatments include adapted cognitive behavioral therapy and mindfulness-based approaches. Though most of this chapter focuses on unipolar depression in ASD as the more well-studied mood disorder, the chapter also summarizes the small research base on bipolar disorder in the context of ASD. It ends with a call for improved screening, assessment, and evidence-based treatment options to address this significant public health problem in this special population.

The Co-Occurrence of Autism and Gender Diversity

Gender diversity refers to gender expressions and/or gender identity experiences that vary from the common experiences of gender. Gender-diverse people may be gender nonconforming, gender nonbinary, gender fluid, gender exploring, transgender, and so forth. Some gender-diverse individuals experience gender dysphoria and/or gender incongruence and may require gender-affirming supports, including gender-affirming medical interventions. The co-occurrence of autism and gender diversity has been highlighted in a series of studies internationally as well as through rich community expressions. Studies in gender-referred individuals reveal high rates of autism traits as well as high rates of existing autism diagnoses. Studies in autistic populations reveal greater gender diversity characteristics. The long-term course of gender diversity in autistic individuals is poorly understood. Clinical guidelines have been developed for adolescents with the co-occurrence, but much work remains: No gender-related measures have been developed and tested for use in neurodiverse populations, no programs exist to support gender-diverse neurodiverse adults, and little is known about co-occurring mental health profiles, risks, or protective factors for people with the co-occurrence. The inclusion of this chapter on co-occurring autism and gender diversity within a book on “co-occurring psychiatric conditions” is problematic, because gender diversity is not a “psychiatric condition,” but instead a form of human diversity. The diagnosis of Gender Dysphoria is useful only insomuch as it allows individuals to obtain necessary gender-related supports. The authors’ choice to include this chapter in this book reflects a compromise, motivated by the need for educating both autism and gender specialists in this common co-occurrence.

Obsessive-Compulsive and Related Disorders in Autism Spectrum Disorder

Obsessive-compulsive and related disorders (OCRDs) are a group of diagnoses that center on compulsive behaviors and/or obsessive thoughts. They include obsessive-compulsive disorder (OCD), body dysmorphic disorder (BDD), hoarding disorder, excoriation disorder, and trichotillomania. Each of the OCRDs are associated with significant psychosocial impairment and family/caregiver burden. Furthermore, these disorders frequently co-occur with autism spectrum disorder (ASD) traits and diagnoses, and differential diagnosis can be difficult. OCD represents the most common of the OCRDs, and also the most well researched to date. Consequently, this chapter focuses on the nature and impact of comorbid OCD and ASD across the lifespan. Unfortunately, preliminary research indicates that individuals with OCD and ASD are significantly more disadvantaged by way of poorer psychosocial functioning, increased family burden/accommodation to symptoms, greater number of other comorbid conditions, and more likely to present with comorbid externalizing disorders. Future research is needed to determine what impact these unique complexities may have on treatment success. Preliminary research suggests that cognitive behavioral therapy (CBT) is of benefit to these individuals with comorbid ASD and OCD; however, modification may be necessary to improve engagement and outcomes (e.g., family inclusion in therapy). This chapter presents a case example of modified CBT for a child with comorbid ASD and OCD, delivered intensively. Future research should focus on the related OCRDs in individuals with ASD, as well as improving current assessment and treatment practices.

Medications to Treat Co-Occurring Psychiatric Conditions in Autism Spectrum Disorder

Although there are as yet no drugs specifically indicated for core symptoms of autism spectrum disorder (ASD), medications are frequently used as a component of comprehensive treatment for co-occurring psychiatric conditions in individuals with ASD across the lifespan. As is true for psychopharmacological treatment in general, the selection of particular therapeutic agents is not yet driven by an understanding of the contributions of specific genetic or other abnormalities to the development or expression of psychiatric symptoms. Treatment is thus largely empirical, and the most common therapeutic targets in ASD include hyperactivity and impulsivity, irritability, mood and anxiety symptoms, and insomnia. The literature suggests that individuals with ASD as a group respond less well to common pharmacologic interventions, and they are generally more likely to experience side effects. There is good evidence to support many of the commonly used medication strategies in ASD, particularly the use of stimulants and other drugs typically prescribed for attention deficit hyperactivity disorder, as well as atypical antipsychotics for a cluster of symptoms captured under the umbrella term of irritability. There is growing interest in exploring the role of drugs that act on glutamatergic and GABAergic systems. Overall, the evidence base to inform the practice of psychopharmacology is relatively limited even for situations where a Food and Drug Administration-approved indication exists, and considerable work needs to be done to better inform clinical practice.

Self-Injurious Behavior in Individuals With Autism Spectrum Disorder

Individuals with autism spectrum disorder (ASD) and other intellectual and neurodevelopmental disabilities are at increased risk for engaging in one or more types of problem behavior (e.g., aggression, property destruction, self-injury). Self-injurious behavior (SIB), the focus of the current chapter, refers to behaviors that produce (or could produce) physical injury to an individual’s own body and is common among individuals with ASD. SIB poses immediate and long-term risks for the individuals and their caregivers. This chapter summarizes the prevalence and developmental course of SIB in individuals with ASD, as well as research on the etiology, diagnosis, assessment, and evidence-based treatments for SIB. Case examples and suggestions for future research are provided.

Understanding Executive Function Challenges in Autism Spectrum Disorder

The construct of executive function (EF) has been referred to as an “umbrella” term for a collection of higher order cognitive processes that guide and manage goal-directed behavior and problem solving. EF impairments are common in autism spectrum disorder (ASD). EF is centrally related to characteristics of ASD and real-world outcomes such as adaptive behavior and quality of life. This chapter describes the profile of EF impairment in ASD and reviews its development across the lifespan and how it affects various aspects of daily functioning (social skills, adaptive behavior, co-occurring psychiatric conditions). The chapter also addresses the challenges assessing of EF and describes promising interventions to promote executive skills in ASD.