Research Paper: Overlooking Childhood Trauma when Diagnosing Attention-Deficit Hyperactivity Disorder (ADHD)

Abstract

This paper explores the connection between trauma and ADHD, in terms of symptomology and etiology. Current diagnostic assessment methods for ADHD are inadequate for those who have experienced trauma. A call for more integrative, trauma-focused screening methods when diagnosing and treating ADHD is recommended.

Keywords: Acute Stress Disorder, adverse childhood experiences (ACEs), Attention-Deficit Hyperactivity Disorder (ADHD), childhood trauma, comorbidity, complex trauma, Disinhibited Social Engagement Disorder (DSED), evidence-based treatments, interpersonal trauma, Posttraumatic Stress Disorder (PTSD), Reactive Attachment Disorder (RAD), trauma screening

Introduction

Attention-Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder that manifests in early childhood and presents as predominantly inattentive (ADHD-PI), predominantly hyperactive-impulsive (ADHD-HI), or combined type (ADHD-C). The severity ranges from mild to severe based on the number of symptoms present across two or more settings, as well as the impairment these symptoms have on the individual’s overall functioning (American Psychiatric Association [APA], 2013). Mash and Wolfe (2019) note that the prevalence of an ADHD diagnosis is “about 5% to 9% of all children and adolescents 4 to 17 years old in North America” (p. 244). The DSM-5 reports rates of 5% in children due to lower worldwide occurrences (APA, 2013). However, despite varying prevalence rates, ADHD is reported in every country that studies it, across all socioeconomic statuses (SES), and amongst males and females at a 2-3:1 ratio respectively (Mash & Wolfe, 2019). ADHD is considered to be a pervasive, lifelong disorder with varying patterns of behavior and intensity based on developmental levels (Mash & Wolfe, 2019). Since ADHD is a common referral problem, it is imperative that the diagnostic screening and assessment tools used are both valid and reliable.

When diagnosing ADHD, it is important to ascertain whether the symptoms are developmentally appropriate or a result of another medical, mental, or neurodevelopmental disorder (APA, 2013). This poses a challenge because approximately “80% of clinic-referred children with ADHD have a co-occurring psychological disorder” (Mash & Wolfe, 2019, p. 244; Canadian ADHD Resource Alliance [CADDRA], 2018), with the DSM-5 highlighting Antisocial Personality Disorder (ASPD), Autism Spectrum Disorder (ASD), Conduct Disorder (CD), Disruptive Mood Dysregulation Disorder (DMDD), Intermittent Explosive Disorder (IED), Major Depressive Disorder (MDD), Obsessive-Compulsive Disorder (OCD), Oppositional Defiance Disorder (ODD), Specific Learning Disorder (SLD), and anxiety, personality, psychotic, substance use, and tic disorders as potential comorbid or differential diagnoses (APA, 2013). In addition, Bipolar Disorder (BP), Intellectual Developmental Disorder (IDD), Reactive Attachment Disorder (RAD), and neurocognitive disorders are included as differential diagnoses to be considered (APA, 2013). Accounting for potential comorbid and differential diagnoses, ensures an accurate diagnosis and treatment plan. While the DSM-5 includes many comorbid and differential diagnoses for consideration, a growing body of research highlights the need for trauma screening when diagnosing ADHD due to the relational course and symptomology.

Traumatic events may be termed in the literature as complex trauma (Conway, Oster, & Szymanski, 2011; Pottinger, 2015), interpersonal trauma (Mash & Wolfe, 2019), and/or adverse childhood experiences (ACEs) (Conway et al., 2011; Brown et al., 2017). Like ADHD, trauma does not discriminate: “in 2017, there were 59,236 child and youth victims (aged 17 years and younger) of police-reported violence in Canada… overall, 33% of children and youth victims had been subjected to violence by a casual acquaintance and 18% by a stranger” (Burczycka, Conroy, & Savage, 2018, p. 4). This is a reduction from the 85,440 substantiated cases in 2008 (Klien, Daminai-Taraba, Koster, & Campbell, 2015). These types of violence included complex and interpersonal forms of trauma, such as neglect, sexual assault, and physical and emotional abuse. These experiences in childhood can lead to diagnosable trauma- and stressor-related disorders such as Acute Stress Disorder, Disinhibited Social Engagement Disorder (DSED), Posttraumatic Stress Disorder (PTSD), and Reactive Attachment Disorder (RAD) in 10-20% of cases (APA, 2013). However, whether diagnosable or not, trauma has a negative impact on childhood development. Based on the 1998 ACEs study, 11-23% of adults have experienced childhood trauma that can “impede an individual’s ability to integrate sensory, emotional, and cognitive information” and present as hyperarousal (Conway et al., 2011, p. 61-2). Having ACE scores increases “a child’s risk for toxic levels of stress, which in turn might impair neurodevelopment, behavior, and overall physical and mental health” (Brown et al., 2017, p. 349-50). Unfortunately, while childhood trauma is far-reaching, this is not often the case for trauma screening.

The ADHD and Trauma Connection

Within the research, the connection between trauma and ADHD has been established. For instance, Ford et al. (2000) found a strong correlation between ADHD and trauma; 25% and 11% of individuals with ADHD experienced physical and sexual abuse respectively and rates of trauma rose to 91% with comorbid ODD. Weinstein, Staffelbach, and Biaggio (2000) also found a correlation between sexual abuse and ADHD. In 2006, Endo, Sugiyama, and Someya found that 14-46% of children with ADHD had experienced abuse. Similarly, Briscoe-Smith and Hinshaw (2006) found that 6 to 12 year old girls with ADHD had experienced higher rates of abuse than the general public – 14.3% to 4.5% respectively. They found that the girls with ADHD who experienced abuse often presented with externalizing symptoms and combined type ADHD. Rucklidge, Brown, Crawford, and Kaplan (2006) surveyed adults with ADHD using the Childhood Trauma Questionnaire and 56% of the individuals with ADHD self-reported childhood trauma. Conway et al. (2011) studied 79 children ages 8 to 18 from Hispanic and African-American backgrounds in an urban psychiatric hospital and found that those with ADHD experienced trauma at higher rates than the general public. Perry and Mackinnon (2012) purported that developmental adversity is a risk factor for the expression of ADHD. In 2013, Biederman et al. studied children in a pediatric setting and found that children from families with higher levels of interpersonal conflict had disproportionately higher rates of ADHD.

While these comparisons were based off of DSM-IV-R assessment criteria, recent studies using DSM-5 diagnostic criteria continue to connect ADHD to trauma. Klein et al. (2015) studied Canadian children in child protection services and found that they “are diagnosed and treated for… ADHD at higher rates than the general population” due to symptom overlap (p. 178). Fuller-Thomson and Lewis (2015) had Canadian adults self-report past childhood physical abuse, sexual abuse, and domestic violence. They found that the first two adverse experiences elevated odds of an ADHD diagnosis in both women and men, whereas domestic violence elevated odds of an ADHD diagnosis in women only. Brown et al. (2017) used a sample of 76,277 children ages 4 to 17 and found that ACE scores and ADHD were associated. Furthermore, they found a gradual relationship between the number of ACE scores and the severity of the ADHD presentation (Brown et al., 2017). In their brain neuroimaging research, Park et al. (2017) found that childhood trauma “strongly predicts the development of ADHD and influences biological processes in offspring” (p. 184). Thus, a clear relationship among trauma and ADHD continues to be substantiated in the literature, yet relatively overlooked in current DSM-5 diagnostic criteria and assessment practices.

Shared Etiology and Symptomology in ADHD and Trauma

ADHD and trauma share similar etiologies and symptomologies. While neurobiological factors rather than psychological factors are often the focus for ADHD and vice versa for trauma, a more integrative approach is preferred. Looking at neurobiological factors, Mash and Wolfe (2019) note that “ADHD appears to be related to abnormalities and developmental delays in the frontostriatal circuitry of the brain and pathways connecting this region with the limbic system, the cerebellum, the thalamus, and the default mode network” (p. 256). Trauma impacts areas of the brain connected to stress, such as the limbic and neuroendocrine systems (Mash & Wolfe, 2019). Similar deficits can be observed in the prefrontal cortex and in gray and white matter abnormalities. Spitzer, Schrager, Imagawa, and Vanderbilt (2017) studied children with PTSD and found that they had “reduced N-acetyl aspartate (NAA), indicating loss of neuronal integrity, in the medial prefrontal cortex… implying a common neuroanatomical etiology” with ADHD brain patterns (p. 345). Similarly, Perry and Mackinnon (2012) found that neglect can lead to an underdeveloped prefrontal cortex and reduced gray matter, leading to externalizing behaviors of impulsivity and reactivity or internalizing behaviors of withdrawal. Park et al. (2016) found white matter anomalies in children with ADHD and in those who had experienced childhood trauma. Furthermore, Park et al. (2017) researched catechol-o-methyltransferase genes on inhibitory deficits in children with ADHD and found “a genetic influence on the association between childhood trauma and the severity of inhibitory deficits in children with ADHD” (p. 183). While an in-depth exploration of brain functioning is beyond the scope and sequence of this research paper, it is important to note the brain connections between childhood trauma and ADHD that may result in similar behavioral presentations.

Psychological factors that are shared amongst ADHD and trauma include low SES, parental separation and divorce, parental mental illness, maternal substance use during pregnancy, and birth complications (Brown et al., 2017; Conway et al., 2011; Dubowitz et al., 2011; Gul & Gurkan, 2018; Mash & Wolfe, 2019; Richards, 2013). Mash and Wolfe (2019) recognize that “family problems may lead to greater severity of symptoms and to the emergence of co-occurring conduct problems” (p. 256), even though ADHD is generally not thought of as being caused by psychosocial factors. Furthermore, stigmatization and lack of family supports and resources can lead to mismanagement and misdiagnosis of symptoms (Fuller-Thomson & Lewis, 2015; Pottinger, 2015; Richards, 2012).

Symptoms of trauma, especially those related to PTSD, often mimic ADHD-like symptoms of hyperactivity and inattention. For instance, internalizing and externalizing behaviors such as inattention, distractibility, disruption, fidgeting, hyperactivity, restlessness, impulsivity, irritability, and poor emotional regulation may be observed in both cases (Briscoe-Smith & Hinshaw, 2006; Conway et al., 2011; Dahmen, Purtz, & Herpertz-Dahlmann, 2012; Endo et al., 2006; Ford et al., 2000; Klein et al., 2014; Park et al., 2017; Perry, 2007; Rucklidge et al., 2006; Spitzer et al., 2017; Szymanski, Sapanski, & Conway, 2011; Weinstein et al., 2000). Spitzer et al. (2017) found that when children cannot rely on a caregiver they adapt in ways that seem disruptive and “may present with signs and symptoms similar to ADHD” (p. 345). ADHD is listed as a differential or comorbid disorder in DSED due to similar impulsivity symptoms (APA, 2013). However, DSED is not listed as a differential or comorbid diagnosis for ADHD despite symptom overlap.

It has been argued that the externalizing symptoms of ADHD are easier to identify than the re-experiencing or avoidance symptoms related to PTSD and trauma, especially in young children (Ford et al., 2000; Klein et al., 2014; Spitzer et al., 2017; Szymanski et al., 2011; Young, Kenardy, & Cobham, 2011). The symptoms can impact relationships, academic performance, and executive functioning (Mash & Wolfe, 2019; Pottinger, 2015). In their study of Canadian children in the welfare system, Klein et al. (2015) found that the anxiety and hypervigilance response to trauma can mimic the hyperactivity and impulsivity found in ADHD. Furthermore, trauma-related avoidant behaviors can present like inattention in ADHD (Spitzer et al., 2017; Szymanski et al., 2011; Weinstein et al., 2000). When both disorders are present, trauma can exasperate symptoms since issues with coping and listening can further create a dysregulated affect (Szymanski et al., 2011). Because the symptoms of trauma and ADHD are closely related, a clinician may miss the signs of trauma and attribute behaviors solely to ADHD.

Evidence-Based Treatment

While the two disorders share behavioral symptoms, the treatment methods and approaches differ. The cost of ADHD in the United States varies between 12 to 17 thousand USD per person due to medical and educational needs (Klein et al., 2015; Mash & Wolfe, 2019). Thus, it is important that the treatments used are evidence-based and tailored to an accurate diagnosis so that they are both helpful and cost-effective. Treatment of ADHD often involves parent management training (PMT), educational and environmental interventions, and/or stimulant medications, such as dextroamphetamine, amphetamine-dextroamphetamine, and methylphenidate (CADDRA, 2018; Conway et al., 2011; Mash & Wolfe, 2019; Richards, 2013). Pharmacotherapy treatment is a common approach backed by the Multimodal Treatment of Attention Deficit Hyperactivity Disorder (MTA) study,but in complicated situations medications should be used in combination with psychoeducational interventions (Klein et al., 2014; Mash & Wolfe, 2019). ADHD treatments focus on treating the behavioral symptoms, whether through stimulant medications and/or environmental adaptations.

Treating trauma, on the other hand, focuses on the root cause(s) first and the specific behavioral symptoms second. These evidence-based treatments include Trauma-Focused Cognitive Behavioral Therapy (TF-CBT), psychotherapy, parent management training through the Triple P Program and Project Safe Care, and/or serotonergic antidepressants for PTSD specifically (Conway et al., 2011; Mash & Wolfe, 2019; Spitzer et al., 2017). The most common approach for PTSD treatment is TF-CBT, which incorporates elements of exposure therapy, narrative writing, role-play perspective taking, parental involvement, family communication, parental training, psychoeducation, safety, and relaxation, self-regulation, and stress management skills (Mash & Wolfe, 2019; Pottinger, 2015; Weisz & Kazdin, 2017). For those diagnosed with RAD or DSED, parenting classes, environmental changes, and counselling are the preferred methods over psychopharmacological treatments (Mash & Wolfe, 2019; Perry & Mackinnon, 2012). In addition, building on protective factors such as family and social supports (Perry & Mackinnon, 2012), connecting families to support resources (Dubowitz et al., 2011), and Duty to Report protocol in childcare professions can support trauma treatment.

At best mistreatment could lead to ineffective approaches; at worst mistreatment could lead to potential harm. For instance, Klein et al. (2015) note concerns such as “prolonged exposure to unhelpful medications, stigmatization, a feeling of being misunderstood and opportunity cost in treating other problems” (p. 183). Furthermore, mistreatment neglects “the underlying emotional, personality, and interpersonal issues” that the child may have (Conway et al., 2011, p. 6). Richards purports that treating children who have experienced trauma with stimulant medication “runs the risk of colluding with an external environment which needs to change, and effectively ‘silencing’ the mechanisms a child is using to communicate that ‘all is not well'” (2013, p. 496). Because ADHD treatments focus on the behaviors, using these treatments with those who have experienced trauma does little to help the child and may overlook the relational and familial problems (Richards, 2013). Briscoe-Smith et al. (2006) found the following:

There are children with ADHD for whom abuse appears to be overlooked diagnostically, either as an etiological factor or an exacerbating variable. If such trauma is not addressed, symptoms associated with it may go unchecked and may even become worse as the child develops. The usual interventions for ADHD (behavioral modification procedures, stimulant medications) may not be the appropriate treatments for traumatized children. (p. 10)

Furthermore, if ADHD-based treatments are used without trauma supports, “symptoms and functional impairments may persist” (Klein et al., 2015, p. 181). Misdiagnosis and thus, mistreatment is predictive of negative outcomes.

If a child has ADHD but also a history of trauma, it is important not to treat each in a vacuum. Not only would the developmental course be more severe (Biederman et al., 2012; Brown et al., 2017; Ford et al., 2000; Szymanski et al., 2011), but both the trauma and ADHD symptoms would require monitoring. Brown et al. (2017) note that “cumulative exposure to traumatic experiences is associated with worse overall ADHD symptom severity” and may explain why solely using ADHD treatments does not work (p. 353). Ensuring safety and trauma symptom stabilization is recommended before treating the comorbid ADHD (Biederman et al., 2013; Perry & Mackinnon, 2012). While children who experience trauma may require medications and behavioral management strategies as part of their treatment, especially when comorbid ADHD occurs, a typical approach would be therapeutic or caused-based, followed by medications or behavior-based treatments. Further research on specific, research-based trauma and ADHD treatments is needed (Briscoe-Smith et al., 2006). Pottinger (2015) has adapted trauma-based strategies to support clients with comorbid ADHD but continued work in the field would be beneficial to ensure validity and reliability.

Moving Forward with Trauma Screening

ADHD and childhood trauma are closely related; thus, it is integral to have screening tools and methods that differentiate between the two. Unfortunately, despite research, trauma screening is not mandatory when exploring an ADHD diagnosis. Spitzer et al. (2017) found that only 44% of general practitioners screened for trauma. Furthermore, Brown et al. (2017) note that “although it has been shown that children exposed to ACEs can manifest many of the disruptive behaviors, impulsivity, and executive dysfunction characteristics of ADHD, comprehensive evaluation for traumatic stressors is not routinely performed during ADHD assessment” (p. 350). They found that only 2-4% of general practitioners routinely screened for ACEs and for one third, trauma screening was not part of their practice. The Canadian ADHD Practice Guidelines briefly mention exploring trauma histories but no specific screening tools are recommended (CADDRA, 2018). The DSM-5 recommends excluding other mental disorders and Reactive Attachment Disorder (RAD) is included as a differential diagnosis with differences in the amount of symptoms shown and attachment styles (APA, 2013). However, research by Szymanski et al. (2011) and Conway et al. (2011) shows that there is diagnostic ambiguity and confusion with determining differential diagnoses. This may be because each child differs in their behavioral presentation. Moving forward, trauma screening should become commonplace to ensure accurate diagnosis, proper care, and cost-effectiveness of treatments.

If trauma screening is to become best practice, having the appropriate tools is necessary. Currently, a pediatrician or family physician would work with an educational psychologist to diagnose ADHD (CADDRA, 2018). Often it is the caregiver or educator whom makes the initial referral and acts as a main source of screening information (Klein et al., 2015), because they have firsthand experience with the child. Since there are no definitive diagnostic tools for ADHD, clinical judgement and triangulation of assessments from multiple sources is necessary. These assessments may include parent and teacher rating scales, such as the Conners Comprehensive Behavior Rating Scales-3 (Conners CBRS-3), Vanderbilt ADHD Diagnostic Rating Scales (VADRS), ADHD Rating Scale, SNAP-IV Teacher and Parent Rating Scales, and Child Behavior Checklist (CBCL) (CADDRA, 2018; Gupta & Kar, 2010). It is important to note that none of these rating scales are intended to diagnose or screen for trauma (Spitzer et al., 2017; Weinstein et al., 2000) and rater-bias may occur (Gupta & Kar, 2010). Furthermore, Brown et al. (2017) report that:

Current rating scales and checklists focus primarily on presenting behaviors and do not query about psychosocial and environmental factors, such as exposure to traumatic stress, which might play an important role in ADHD symptom onset and progression and if identified, can help clinicians determine helpful components of multimodal therapy. (p. 350)

From a best-practice standpoint, the connection between trauma and ADHD should lend itself to clinical consideration of both concerns even when a diagnosis of ADHD seems obvious.

Moving forward, clearer diagnostic guidelines, mandatory trauma screening protocol, and more education on the relationship between trauma and ADHD would be beneficial. Furthermore, including trauma as a comorbid or differential diagnosis to ADHD would help foster accurate diagnoses. Multi-agency collaboration between child protection workers, educators, psychologists, pharmacists, and doctors may help support accurate diagnosis of comorbid or differential ADHD and trauma. Asking direct questions about experiences of abuse and other trauma, probing further with similar symptomology, exploring developmental histories, observing children in their natural environments, and using rating scales in addition to written self-reports and medical exams is recommended (Mash & Wolfe, 2019; Ford et al., 2000; Richards, 2013; Weinstein et al., 2000). In addition, asking targeted questions about onset, duration, frequency, thoughts and feelings, environments, activities, family relationships, and the people around when certain symptoms occur is warranted to determine patterns of ADHD-like behavior from trauma-related symptoms. All children deserve an accurate diagnosis and treatment plan that deals with the complexity of their lives; we need an integrative, all-encompassing approach to diagnosing ADHD so that trauma will not be overlooked for any child with the misfortune.

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