Managing ADHD in High School Students: Diagnosis and Therapeutic Interventions

Abstract: With the changes in the recently published fifth edition of the Diagnostic and Statistical Manual of Mental Disorders, the prevalence of attention-deficit/hyperactivity disorder (ADHD) in high school students is likely to increase, not decrease. Thus, pediatricians must be familiar with diagnostic and treatment practices in this population. Diagnostic considerations (both for reassessing an ADHD diagnosis made in childhood as well as for making a de novo ADHD diagnosis during the high school years), evidence-based clinical interventions and their associated risks, and issues specific to managing ADHD in high school students are discussed.

The childhood-onset constellation of impairing inattentive and/or hyperactive-impulsive symptoms has been described in the literature for more than 200 years.¹ Despite this, the disorder we now refer to as attention-deficit/hyperactivity disorder (ADHD) has undergone many changes.

Recently, the American Psychiatric Association published the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5).² The new edition includes several changes from its precursor, the DSM-IV-TR,³ including the following²:

• Behavioral descriptions of ADHD symptoms that are more applicable to adolescents and adults

• A lower diagnostic threshold (5 symptoms of inattention and/or 5 symptoms of hyperactivity-impulsivity) for individuals aged 17 years and older compared with those aged 16 years and younger (6 symptoms)

• The age of onset criterion has been raised from age 7 years to age 12 years and now stipulates that several inattentive or hyperactive-impulsive symptoms need be present

• The impairment criterion has been changed substantially and now indicates that the ADHD symptoms “interfere with or reduce the quality of functioning” rather than cause clinically significant functional impairment (as stipulated in the DSM-IV-TR)

• Autism spectrum disorders are no longer an exclusionary criteria for making an ADHD diagnosis.

It is too early to know how these diagnostic changes will affect working with high school students, although it seems reasonable to suggest that the changes will increase the prevalence of ADHD in high school populations. Given this likely outcome, it is important for pediatricians to be familiar with evidence-based diagnostic and therapeutic practices for managing ADHD in high school students. This article discusses diagnostic considerations for reassessing an ADHD diagnosis made in childhood as well as for making a de novo ADHD diagnosis in high school; evidence-based clinical interventions and the risks associated with them (eg, stimulant misuse, stimulant diversion); and issues specific to managing ADHD in high school students (eg, motor vehicle operation).

High School ADHD Basics

Using data from the Centers for Disease Control and Prevention,⁴ the overall prevalence of ADHD in the United States has increased dramatically over the past 30 years. With an overall pediatric prevalence of 9.5%, ADHD is the most common neurobehavioral disorder of childhood. However, it is striking that the prevalence rates are the highest in the high school age population, with 13.6% of those aged 15 to 17 years ever having received a diagnosis of ADHD.⁴ Boys are roughly 2.5 times more likely to receive a diagnosis of ADHD than are girls.⁴

The majority of children (50% to 70%) who receive a diagnosis of ADHD will maintain their ADHD diagnosis into adulthood.⁵ The fact that not all children with ADHD will develop into adults with ADHD likely is a reflection of the natural decline of ADHD symptoms in typically developing populations^6,7 and/or the developmental insensitivity of diagnostic algorithms.⁸ Conversely, delays in cortical maturation in children with ADHD may help explain why the majority of children with ADHD continue to have impairing ADHD symptoms into high school. Neuroimaging data suggest that cortical development in children with ADHD lags behind that of typically developing children by several years, most prominently in the prefrontal cortex.⁹ The prefrontal cortex is the area of the brain that subserves a variety of cognitive functions with which individuals with ADHD often struggle, including the “executive control” of attention, evaluation of reward/punishment contingencies, and working memory. Thus, as a function of delayed cortical maturation, many children with ADHD will become high school students with ADHD.

Having a family history of ADHD is a significant predictor of which children with ADHD will maintain their diagnosis into high school.^10,11 For example, parents of children whose ADHD persisted into high school were 20 times more likely to have ADHD themselves than were parents of controls¹²; in comparison, parents of children with nonpersistent ADHD showed only a fivefold increased risk.¹² In addition to having a family history of ADHD, having more-severe childhood ADHD symptoms, having a comorbid psychiatric disorder (especially depression or oppositional defiant disorder), and the presence of psychosocial adversity (eg, poverty, maltreatment) all increase the likelihood the diagnostic persistence of ADHD into the high school years.^13,14

Compared with childhood ADHD (and even adult ADHD), far less information is known about ADHD in high school students. Of the data that have been published, it appears that the functional impairments that were present in elementary and middle school often intensify in high school.^15-17 The impact of ADHD on high school students is greatest in the areas of classroom performance, homework management, and disruptive behaviors.¹⁸ High school students with ADHD are less likely to pursue postsecondary education, and they obtain lower-status employment than do their typically developing peers.^19-21 All of these observations suggest that ADHD is not the benign condition that often is portrayed in the popular media,²² and pediatricians need to be familiar with evidence based diagnostic and treatment practices.

Diagnostic Considerations

Reassessing ADHD in a previously diagnosed adolescent. Given that 30% to 50% of children with ADHD will outgrow their ADHD diagnosis and be less impaired by their ADHD symptoms,⁵ careful attention should be paid to reassessing ADHD diagnostic status in high school students. Although the high school student may have an existing diagnosis, it is generally helpful to review the age of onset to ensure that the developmental requirement for ADHD symptoms has been met.

Similar to an initial diagnostic evaluation for ADHD in elementary school aged children, the use of parent-, teacher-, and self-report rating scales is central to the evaluation in high school aged children. A variety of broad-band scales (eg, Behavior Assessment System for Children, Second Edition²³) and narrow-band scales (ADHD Rating Scale–IV⁶) exist to aid clinical decision-making. Given that inattention and impulsivity are rather nonspecific symptoms and that DSM-5 criterion 5 requires the ruling out of alternative explanations for the ADHD symptoms, the use of both a broad- and narrow-band instrument is suggested.

Once the diagnostic threshold of 6 symptoms (or 5 if the student is aged 17 years or older) is met, the pediatrician can assess the cross-setting nature of the ADHD symptoms and how significantly these symptoms interfere with or reduce the quality of functioning. Finally, alternative explanations for the ADHD symptoms need to be ruled out. Unlike in childhood, during which substance abuse presents more rarely, in high school substance abuse increases in prevalence,²⁴ especially in individuals with childhood ADHD.²⁵ While it is certainly possible to have ADHD and a comorbid substance abuse disorder,^26,27 careful delineation of the timeline of ADHD symptoms is particularly important when attempting to reassess ADHD in high school students with substance abuse histories.

In addition to substance abuse, internalizing disorders such as depression and anxiety need to be considered as better explanations for inattentive and impulsive symptoms. Longitudinal studies following children with ADHD into adolescence suggest that depression and anxiety disorders are common psychiatric comorbidities (25% to 30%) with ADHD,²⁷ especially for children with ADHD who maintain their ADHD diagnosis as adolescents.¹³ These data suggest that ADHD often occurs concomitantly with anxiety and depression, thus complicating the diagnostic reassessment. Similar to when substance abuse is present, a careful delineation of the timeline of ADHD and anxious/depressed symptoms is important when attempting to reassess ADHD in high school students.

Unless there is a clear history of a medical condition (eg, concussion, diabetes mellitus, hypothyroidism, seizure disorder), routine laboratory tests and neuroimaging are not indicated in an ADHD evaluation. Psychological testing can be helpful if a learning disability or cognitive factors are suspected as a primary reason for inattentive symptoms in the academic setting; however, routine psychological testing is not sensitive or specific for the diagnosis of ADHD in a high school student.

Making an initial diagnosis of ADHD in a high school student. While the DSM-5 states that several inattentive or hyperactive-impulsive symptoms need to be present before age 12, it is likely that a high school student will present for an ADHD assessment without the disorder ever having been diagnosed before. In my experience, the student himself or herself, rather than a parent or teacher, more often initiates these evaluation requests. Similar to the reassessment of ADHD in a high school student with an existing ADHD diagnosis, establishing a timeline of ADHD symptoms (especially inattentive symptoms) is crucial in adolescents who do not have an existing ADHD diagnosis.²⁸ The DSM-5 impairment criterion has been changed substantially and now indicates that the ADHD symptoms “interfere with or reduce the quality of functioning.”² Thus, it is conceivable that more high school students who had relatively benign symptoms during childhood (yet who clearly had symptoms that affected functioning) and whose symptoms now are affecting functioning more robustly, will be receiving an ADHD diagnosis de novo in high school.

To aid in making a new diagnosis of ADHD in a high school student, it is most important to first assess functioning (eg, how is he doing in school? How well is she doing in her after-school job?), not symptoms. In addition to assessing functioning, it is also critical to establish the cross-setting nature of the ADHD symptoms. Inattentive symptoms that only occur at school and during homework time most likely do not indicate ADHD and probably are better explained by other factors (eg, interest level, motivation, relative strengths and weaknesses in cognitive abilities).

After functioning and the cross-setting nature of the symptoms have been established, separate interviews with the adolescent and parents should follow.²⁹ To maximize sensitivity to an ADHD diagnosis, carefully assess the timeline of ADHD symptoms and the extent to which these symptoms, and not other factors, explain any functional difficulties that may be present.

Evidence-Based Therapies

Similar to the evidence-based treatment approaches to managing childhood ADHD, the adolescent ADHD evidence base supports a combined treatment intervention of pharmacotherapy (often with stimulants) and psychosocial/behavioral intervention.²⁹ Stimulant medications have medium to large effect sizes for decreasing ADHD symptoms, yet they positively affect functioning (especially academic) less robustly.³⁰ In addition to stimulant medications, nonstimulant medications such as atomoxetine, bupropion, clonidine, and guanfacine often are employed for managing ADHD in adolescents. Stimulant medications, however, generally are considered the frontline approach for managing adolescent ADHD.³¹

Pediatricians who manage stimulant medications for high school students should be aware of the most common adverse effects: onset insomnia, appetite reduction, and headaches,²⁸ of which appetite loss is most likely to be more consistent over time.³² While acute cardiovascular effects (eg, blood pressure changes, heart rate changes) have been reported in a number of short-term studies,³³ most judge these changes as clinically insignificant.³⁴ A reduced growth rate typically occurs with stimulant treatment initiation (during the first year of therapy) and lessens over time.³⁵ Baseline height and weight values are positively associated with diminished growth; in other words, heavier and taller children experience the most growth delay.³⁶

Much data have been published on the efficacy of stimulants for adolescents with ADHD, yet far less data have been published on psychosocial interventions.³⁷ Of the interventions that have been tested empirically, highly structured academic activities (eg, note-taking), classroom-based individualized behavior management programs, and family-based interventions have demonstrated the most promise.²⁹

Maximizing stimulant treatment adherence. Developmentally, typically developing high school students strive for independence and autonomy, and parents, expecting more functional independence, may rely on the adolescent to manage his or her own medications. These are 2 possible factors that explain why adherence to stimulant medications wanes as a function of age.^32,38 In addition to typically developing phenomena, symptoms of oppositional defiant disorder that manifest at school are a strong predictor of failure to adhere to stimulant treatment.³⁹

In conjunction with being aware of which high school students are more likely to not adhere to treatment, certain strategies also may be beneficial. Rather than immediate-release stimulant formulations, the use of extended-release formulations is recommended by the American Academy of Child and Adolescent Psychiatry as a frontline management strategy.²⁹ For high school students in whom poor adherence is attributable to inadequate response or intolerance of adverse effects, a nonstimulant medication may prove helpful in increasing treatment adherence.²⁹ Moreover, the use of conjunctive therapies such as psychotherapy also may help high school students adhere better to stimulant treatment.³⁷

Minimizing stimulant misuse or diversion. Stimulant misuse or diversion is a real possibility for any high school student,⁴⁰ and especially so for students with a comorbid conduct disorder or substance abuse diagnosis.^41,42 In general, research suggests the motivating factors for stimulant misuse can be broken into 2 primary domains: for performance enhancement or cognitive enhancement,^43-49 and to achieve a high.^44-46,48-52 Because the delivery for some medications (eg, lisdexamfetamine⁵³) to the brain is slower, and extraction of the active drug ingredients is more difficult, the use of extended-release formulations offers some protection from stimulant misuse and diversion. In addition to the use of an extended-release formulation, the use of a nonstimulant medication also can reduce the risk of drug misuse and/or diversion.^54,55

High School & ADHD: Common Challenges

Motor vehicle operation. While not specific to ADHD, high school students are more likely than any other age cohort to have an automobile accident.⁵⁶ Nonetheless, ADHD is associated with risk-taking and thrill-seeking behaviors.⁵⁷ Data suggest that, possibly as a function of risk-taking or of less driving knowledge,⁵⁸ high school students with ADHD have more at-fault automobile accidents and speeding tickets, are more likely to have driven a car without a license, and are more likely to have had their license suspended.^59,60 These driving outcomes are especially likely in the presence of comorbid conduct disorder.⁶⁰

Stimulants can be effective in improving motor vehicle operation outcomes in high school students with ADHD.^61-64 Given that high school students with ADHD may be driving their vehicle during the late afternoon or evening, extended-release formulations again appear to be the optimal medication to lessen the risk of motor vehicle operation impairments.

Transition to adult-care providers. Facilitating the transition to adulthood has been an increasing focus in the ADHD literature.^65,66 The transition to adulthood is defined by young adults themselves as accepting responsibility for oneself, gaining autonomy and independence, and becoming financially independent.^67,68 In many ways, these attributes and qualities often are very difficult for high school students with ADHD. Many psychosocial treatment approaches for high school students focus explicitly on these domains, although the outcomes data on the effectiveness of these interventions at improving these functional domains are rather sparse.

Adult health care providers often report feeling less equipped to manage ADHD than do pediatric providers.⁶⁹ In addition to increasing training in residency programs for internal medicine and adult psychiatry, it has been suggested that guidelines be created and adopted for ensuring the best transfer of care between child and adult health care providers for high school students with ADHD.

To facilitate the transfer of care, having a warm, empathic provider whom the high school student trusts appears to be a key factor.⁷⁰ In ADHD, parental input may be desired (or required) to allow for better transfer of care to adult providers, especially in the early stages of transition.⁷⁰ Nonetheless, the high school student needs to be an active and engaged participant in the transition process. Ideally, early in high school, transition planning will begin with opportunities to meet adult health care providers and visit the office.⁷¹

Interestingly, high school students with more complex ADHD (ie, ADHD and a comorbid psychiatric disorder) appear to transition easier to adult mental health care.⁷⁰ This possibly is due to the adult care providers’ having more knowledge about how to manage the psychiatric comorbidities (eg, depression, anxiety, substance abuse) relative to uncomplicated ADHD.⁷⁰

Dr Antshel is an associate professor of psychology and director of clinical training at Syracuse University in Syracuse, New York.

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