APPROACH
APPROACH
Definitions:
DISTRACTIBILITY: Inability to focus attention for age-appropriate periods of time.
HYPERACTIVITY: Excessive activity significantly above the level expected for the setting and the individual’s developmental stage.
IMPULSIVITY: Taking action without appropriate thought and consideration, which often leads to a dangerous situation.
Clinical Presentation
ADHD is characterized by a consistent pattern of inattention and/or hyperactivity/impulsivity that is more pronounced or frequent than expected for a given stage of development. Symptoms must persist for a minimum of six months, begin before the age of 12, and be evident in multiple settings (e.g., home and school). It is essential to recognize that in less structured home environments, parents may not always notice the child’s short attention span or excessive hyperactivity and impulsivity. In such cases, gathering observations from other sources beyond school, such as daycare providers, after-school programs, or babysitters, is crucial to confirm the pervasiveness of ADHD symptoms.
The prevalence of ADHD is estimated to be between 3% and 5% in prepubertal children, with boys more frequently diagnosed with the hyperactive-impulsive subtype compared to girls. The inattentive subtype is marked by difficulty paying attention to details, trouble maintaining focus on tasks, difficulty following instructions, struggles with task organization, frequently misplacing items, being easily distracted by external stimuli, and forgetfulness in daily activities. Hyperactivity is exhibited through excessive fidgeting, difficulty remaining seated in a classroom, being overly loud during play, and persistently high levels of motor activity that are not significantly influenced by social context. Impulsivity is demonstrated by blurting out answers, struggling to wait in line or take turns, frequently interrupting others, and excessive talking without appropriate responses in social interactions. Table 3-1 outlines the diagnostic criteria for ADHD.
Nearly two decades of research confirm that a substantial proportion of individuals diagnosed with ADHD in childhood continue to exhibit symptoms into adulthood. Long-term studies tracking individuals for years or even decades after their initial diagnosis indicate that ADHD does not simply disappear at a specific age.
Research also found that the DSM-IV criteria were as effective for diagnosing adults as they were for children, though a lower threshold of symptoms (five instead of six) was deemed sufficient for a reliable diagnosis.
Pathophysiology
While the precise cause of ADHD remains unclear, evidence suggests it results from decreased activity in dopaminergic and noradrenergic pathways in several regions of the prefrontal cortex. The dorsal anterior cingulate gyrus plays a role in selecting what an individual focuses on, whereas the dorsolateral prefrontal cortex is involved in maintaining attention and executive functioning. Both areas appear to be implicated in ADHD. Impairment in the prefrontal motor cortex is thought to contribute to hyperactivity, while decreased activity in the orbitofrontal cortex is associated with impulsivity. The severity of ADHD symptoms in a child depends on the degree of impairment in these specific areas of the prefrontal cortex.
Differential Diagnosis
ADHD frequently coexists with oppositional defiant disorder (ODD) or conduct disorder (CD) in children and adolescents. It is crucial to recognize that medication can only:
1. Help the child sit still—if the child wants to sit still.
2. Help the child focus their attention—if the child wants to pay attention.
3. Help the child think before acting—but will not influence whether they make good decisions.
Failure to identify ODD or CD in a child with ADHD often leads clinicians to attempt to medicate away deliberate disruptive behavior. ADHD, particularly when combined with ODD, can sometimes be mistaken for childhood bipolar disorder (see Case 8 for a detailed discussion).
Many children with ADHD also have learning disabilities, so a thorough evaluation should be conducted after optimizing ADHD symptom management. Early-onset bipolar disorder may present with restlessness and distractibility, but symptoms in these cases have an additional affective component. Lead intoxication can also cause hyperactivity, making it important to measure blood lead levels during initial evaluations.
Petit mal seizures can sometimes be mistaken for poor attention in ADHD. However, careful history-taking often reveals episodes where the child briefly loses awareness of their surroundings or experiences “lost time” (absences). In contrast, children with inattentive ADHD typically report that their minds were occupied with something else during inattentive moments. Parents and teachers should be asked about staring spells where the child is unresponsive even when directly spoken to, as this could indicate petit mal seizures. If uncertainty remains, an electroencephalogram (EEG) should be performed.
Treatment
First-Line Medications
Current American Academy of Child and Adolescent Psychiatry (AACAP) guidelines recommend treating ADHD with either stimulant medications or atomoxetine. Approximately 70% to 80% of children with ADHD respond to stimulant medications, which include methylphenidate and amphetamine preparations.
Common side effects of stimulants include:
• Decreased appetite (which can slow growth rate)
• Initial insomnia
• Irritability
• Dysphoria
• Headaches
In some cases, stimulants can trigger or worsen tics in children with tic disorders. Stimulants have a rapid onset of action, but their effects typically wear off by the end of the day.
Atomoxetine is a selective norepinephrine transporter inhibitor and serves as an effective alternative for ADHD treatment. It is often preferred in cases where:
- Substance abuse issues exist in the family (since atomoxetine is not a controlled substance).
- The child has tics, as it does not worsen them like stimulants.
- The patient has comorbid anxiety disorders.
Unlike stimulants, atomoxetine takes 2 to 3 weeks to show effects and provides 24-hour symptom control once it becomes effective. Some patients report sedation, but it generally promotes good sleep.
Both stimulants and atomoxetine can reduce appetite, making regular height and weight monitoring essential to assess any impact on growth.
Second-Line Medications
For children who do not respond to stimulants or atomoxetine, alternatives include clonidine and guanfacine. These medications are often prescribed at low doses to address sleep disturbances or agitated behavior in children already stabilized on ADHD medication. Clonidine and guanfacine can be used alone or in combination with a stimulant.
Third-Line Medications
Other medications with demonstrated effectiveness for ADHD include bupropion and imipramine, which are considered third-line treatments.
- Imipramine requires blood level monitoring and ECGs due to the risk of QT prolongation.
- Bupropion is contraindicated in individuals with seizure disorders and can worsen tics due to its dopaminergic action.
Behavioral Therapy
Behavioral therapy alone is typically not sufficient for treating ADHD. However, once medication has effectively controlled symptoms, behavioral parent training can be beneficial in helping parents adjust their parenting strategies to better accommodate their child’s needs. Additionally, classroom behavior modification techniques can be helpful.
Other forms of psychotherapy, aside from behavioral parent training and classroom behavior modification, have not yet been convincingly demonstrated as effective treatments for ADHD.