Attention-Deficit / Hyperactivity Disorder

Sarah Walser, M.D., Matthew Burkey, M.D., Carisa Perry-Parrish, Ph.D.

DEFINITION

  • Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental, chronic disorder involving a persistent pattern of inattention and/or hyperactivity/impulsivity that interferes with functioning or development.
    • Inattentive symptoms includes poor attention to details with frequent careless mistakes, difficulty maintaining attention during tasks, not paying attention when spoken to directly (i.e. wandering mind), trouble following through on projects to completion (i.e. easily sidetracked ), difficulty organizing one’s self (i.e. frequently messy, missed deadlines, trouble completing sequential tasks), avoiding or disliking tasks that require sustained attention, often losing things, frequently distracted by irrelevant things, and forgetfulness (i.e. keeping appointments, chores/ errands).
    • Hyperactive symptoms include prematurely blurting out answers (i.e. before the question is asked or other person’s sentence is complete), trouble waiting one’s turn, frequently interrupting or intruding on others, fidgeting, difficulty remaining seated when expected, restlessness, or difficulty remaining quiet during activities.
  • ADHD is classified under the Neurodevelopmental Disorders section of the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5-TR)[1].
    • The DSM-5 has an extensive, but not exhaustive, list of criteria for ADHD. For these detailed criteria, please see the DSM-5-TR itself[1].
    • The criteria-based diagnosis requires meeting of inattention and/or hyperactivity-impulsivity criteria, onset before age 12, occurrence in two or more settings, and resulting impairment in functioning.

EPIDEMIOLOGY

  • ADHD is the most common neurodevelopmental disorder. It affects approximately 5.9% of youth and 2.5% of adults worldwide[2].
  • The majority of ADHD is the result of variety of genetic and environmental factors.
  • More frequent in males than females, with ratio of 2:1 in children and 1.6:1 in adults
    • Females may be more likely to present primarily with inattentive features.
  • Risk factors:
    • Temperament (e.g., reduced behavioral inhibition and effortful control, increased negative emotionality and novelty-seeking)
    • Environmental (e.g., very low birth weight: < 1500g, in utero exposures)
    • Genetic: substantial heritability

DIAGNOSIS

Clinical Presentation

  • ADHD is a multifaceted disorder that varies greatly in symptom type and severity.
  • Along with inattention, hyperactivity, and impulsivity, difficulties with emotion regulation, cognitive deficits, and multiple comorbidities are common (e.g., learning disorders, oppositional defiant disorder).
  • ADHD is often a lifelong disorder, with 85% of adolescents and 50% of adults exhibiting residual symptoms. However, there is evidence that suggests that although children may outgrow some symptoms, most do continue to struggle with some degree of impairment that may fluctuate throughout adulthood[3][4].
  • Poor social/interpersonal functioning and negative self-attitude are common, along with poor frustration tolerance and irritability. People with ADHD may struggle with lower quaility of life, relationship difficulties, and educational and/or career underachievement.
  • ADHD is associated with increased risk for substance use disorders, depression and suicide attempts.
  • ADHD is associated with premature death, which may be related to increased impulsivity. A recent large observational cohort study suggested that pharmacologic treatment of ADHD resulted in lower all-cause mortality over a 2-year period, particularly death due to unnatural causes[5].

Tests and Procedures

  • ADHD is a clinical diagnosis based on developmental history, clinical interview regarding symptoms/impairment, and objective ratings of inattention and/or hyperactivity/impulsivity across multiple settings, with multiple informants (e.g., parents, teachers).
  • When assessing adults, collateral and developmental data is needed to document developmental onset.
  • People struggling with a mood disorder and/or anxiety may also find that they have difficulty paying attention. Certain medicines (ie, benzodiazepines) or drug use (ie, cannabis) can also mimic ADHD. Therefore a careful history and collateral information is important in making an accurate diagnosis.
  • There is no diagnostic laboratory test or imaging modality to diagnose ADHD.
    • However, etiology-specific tests, such as TSH or serum lead levels may be helpful when hyperthyroidism or lead poisoning are suspected by history or examination.
  • In the pediatric population, common ADHD screening measures include:
    • Broad-band measures of psychopathology
      • e.g., the Child Behavior Checklist, the Behavior Assessment Scale for Children
    • Narrow-band measures that are specific to ADHD and common comorbidities
  • For the adult population, there are a few ADHD-specific screening tools available for self and informant ratings:
    • e.g., the Barkley Adult ADHD Rating Scale–IV, the Adult ADHD Self-Report Scale, the Conners Adult ADHD Rating Scale (CAARS)
    • Some measures focus on assessment of childhood ADHD symptoms in patients who present as adults.
      • e.g., the Wender Utah Rating Scale
  • Some patients may benefit from psychological testing to clarify whether cognitive deficits should be addressed in treatment.
    • e.g., to assess for low intelligence, executive dysfunction, and learning disabilities
  • Computerized tests show modest correlations with parent and teacher ratings and do not detect inattention unique to ADHD.
    • e.g., the CPT-II

Differential Diagnosis

TREATMENT

General

  • A combination of stimulant medication and behavior therapy is first-line treatment.
  • Treatment may involve home-, clinic-, and school-based efforts.
  • Psychoeducation is useful to increase parent, teacher, and self-knowledge about ADHD symptoms and effects on behavior and emotions.
  • Family involvement and control of behaviors (e.g. noncompliance, oppositionality, rule-breaking) are beneficial.

Pharmacotherapy

  • Most youths and adults with ADHD respond favorably to psychostimulants (e.g., derivatives of methyphenidate and amphetamine).
    • Efficacy in preschoolers is more modest.
    • Common adverse effects include appetite decrease, weight loss, insomnia, and headache.
      • These may improve with dose adjustment or switching to another stimulant.
    • Coexisting substance use disorders may increase the risk for diversion of stimulants.
      • Osmotic delivery systems (e.g., Concerta) may reduce inappropriate use.
    • For young patients and any patients with difficulties swallowing pills, liquid preparations are available.
      • e.g., dextroamphetamine, ProCentra, methylphenidate HCl, Quillivant
  • Nonstimulant medications have more modest effects and typically take longer to produce therapeutic responses.
    • e.g., atomoxetine, guanfacine, and bupropion
    • These may be useful when stimulants side effects are intolerable or as adjunctive treatment.
  • To optimize medication treatment, pre- and post-treatment parent and teacher ratings are recommended until adequate dosing is achieved with minimal adverse effects.

Psychotherapy

  • Behavior therapy (i.e., parent management training) is effective as front-line treatment for mild ADHD and recommended as an adjunctive treatment for moderate-to-severe ADHD.
  • Comorbid disruptive behavior (e.g., ODD) is also an indication for behavior therapy.
  • Cognitive behavioral therapy (CBT) may be appropriate in older children, adolescents, and adults with comorbid internalizing symptoms (e.g., anxiety, depression).
  • CBT in older adolescents and adults on stable stimulant doses may help manage residual symptoms of ADHD (e.g., disorganization, time management).
  • Consulting with schools about behavior management and supports is recommended.

Other

  • ADHD is a chronic disease with early onset and frequent progression into adulthood.
  • Engagement in prosocial, healthy activities is recommended (e.g., sports, social activities, exercise).
  • Vitamins, dietary supplements, and other alternative/complementary approaches lack scientific evidence of effectiveness.

WHEN TO REFER

  • Pediatricians and other primary care physicians manage the majority of patients with ADHD.
    • Pediatricians are well-positioned to diagnose and treat uncomplicated ADHD.
  • ADHD without hyperactivity/impulsivity may be more difficult to detect.
  • ADHD over diagnosis and over treatment may be common in some community settings.
  • Seek psychiatrist consultation if the patient exhibits unusual reactions to stimulants or fails three trials of stimulant medications.
    • Patients with preexisting cardiac disease should undergo cardiologic evaluation prior to initiating a stimulant medication.
  • Consider referring to a child psychologist or psychiatrist when multiple comorbid conditions.
    • e.g., learning issues, social problems, internalizing/externalizing disorders

FOLLOW UP

  • The need for ongoing behavior therapy can be determined by a child’s level of functional impairment and co-occurring behavioral difficulties.

COMMENTS

  • ADHD is associated with other psychiatric disorders, notably disruptive behavior problems, internalizing disorders, and later substance use problems.
    • These will need to be addressed during treatment.
  • All ADHD subtypes in childhood predict adolescent depression/dysthymia and suicide attempts, underlining the need for ongoing treatment across development.
  • Attention and impulsivity/hyperactivity are dimensional in nature.

PATIENT EDUCATION

Patient Education Author:
Sarah Walser, M.D.
  • ADHD is a neurodevelopmental disorder that begins in childhood and can persist into adulthood. This means that symptoms of ADHD are always present in childhood even if a diagnosis does not occur until adulthood. Some people find that symptoms improve as their brain develops into adulthood. Worldwide prevalence of ADHD is approximately 2-6% among adults and 7-10% among children.
  • Symptoms of ADHD include features of inattention, hyperactivity, or both. People who meet diagnostic criteria for ADHD have at least six symptoms of inattention and/or hyperactivity, and they demonstrate significant impairment in their functioning in multiple areas of their life (such as school, work, and at home).
    • Inattentive symptoms includes poor attention to details with frequent careless mistakes, difficulty maintaining attention during tasks, not paying attention when spoken to directly (i.e. wandering mind), trouble following through on projects to completion (i.e. easily sidetracked ), difficulty with organization (i.e. frequently messy, missed deadlines, trouble completing sequential tasks), avoiding or disliking tasks that require sustained attention, often losing things, frequently distracted by irrelevant things, and forgetfulness (i.e. keeping appointments, chores/ errands).
    • Hyperactive symptoms include prematurely blurting out answers (i.e. before the question is asked or other person’s sentence is complete), trouble waiting one’s turn, frequently interrupting or intruding on others, fidgeting, difficulty remaining seated when expected, restlessness, or difficulty remaining quiet during activities.
  • It is important to talk to your doctor about your symptoms since difficulty paying attention or feeling restless can be instead related to other conditions. For example, people struggling with a mood disorder and/or anxiety may also find that they have difficulty paying attention, but the treatment for these conditions is different. Certain medicines (ie, benzodiazepines) or drug use (ie, cannabis) can also mimic ADHD.
  • Treatment for ADHD can involve behavioral and/or occupational therapy and medications. Medications include both stimulants, like amphetamines and methylphenidates, and non-stimulants, like serotonin norepinephrine reuptake inhibitors (atomoxetine) and alpha agonists (guanfacine, clonidine). Antidepressants like bupropion and tricyclic antidepressants are also sometimes used.
  • Learn more and find support resources at Children and Adults with Attention Deficit Hyperactivity Disorder (CHADD).

References

  1. American Psychiatric Association. (2022). Diagnostic and statistical manual of mental disorders (5th ed., text rev.; DSM-5-TR)
  2. Faraone SV, Banaschewski T, Coghill D, et al. The World Federation of ADHD International Consensus Statement: 208 Evidence-based conclusions about the disorder. Neurosci Biobehav Rev. 2021;128:789-818.  [PMID:33549739]
  3. Sibley MH, Arnold LE, Swanson JM, et al. Variable Patterns of Remission From ADHD in the Multimodal Treatment Study of ADHD. Am J Psychiatry. 2022;179(2):142-151.  [PMID:34384227]
  4. Sibley MH, Kennedy TM, Swanson JM, et al. Characteristics and Predictors of Fluctuating Attention-Deficit/Hyperactivity Disorder in the Multimodal Treatment of ADHD (MTA) Study. J Clin Psychiatry. 2024;85(4).  [PMID:39431909]
  5. Li L, Zhu N, Zhang L, et al. ADHD Pharmacotherapy and Mortality in Individuals With ADHD. JAMA. 2024;331(10):850-860.  [PMID:38470385]
  6. Adler LA, Dirks B, Deas P, et al. Self-Reported quality of life in adults with attention-deficit/hyperactivity disorder and executive function impairment treated with lisdexamfetamine dimesylate: a randomized, double-blind, multicenter, placebo-controlled, parallel-group study. BMC Psychiatry. 2013;13(1):253.  [PMID:24106804]
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  8. Becker SP, Langberg JM, Luebbe AM, et al. Sluggish Cognitive Tempo is Associated With Academic Functioning and Internalizing Symptoms in College Students With and Without Attention-Deficit/Hyperactivity Disorder. J Clin Psychol. 2013.  [PMID:24114716]
  9. Chronis-Tuscano A, Molina BS, Pelham WE, et al. Very early predictors of adolescent depression and suicide attempts in children with attention-deficit/hyperactivity disorder. Arch Gen Psychiatry. 2010;67(10):1044-51.  [PMID:20921120]
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  11. Kessler RC, Adler L, Barkley R, et al. The prevalence and correlates of adult ADHD in the United States: results from the National Comorbidity Survey Replication. Am J Psychiatry. 2006;163(4):716-23.  [PMID:16585449]
  12. Lara C, Fayyad J, de Graaf R, et al. Childhood predictors of adult attention-deficit/hyperactivity disorder: results from the World Health Organization World Mental Health Survey Initiative. Biol Psychiatry. 2009;65(1):46-54.  [PMID:19006789]
  13. McGee RA, Clark SE, Symons DK. Does the Conners' Continuous Performance Test aid in ADHD diagnosis? J Abnorm Child Psychol. 2000;28(5):415-24.  [PMID:11100916]
  14. Riccio CA, Reynolds CR. Continuous performance tests are sensitive to ADHD in adults but lack specificity. A review and critique for differential diagnosis. Ann N Y Acad Sci. 2001;931:113-39.  [PMID:11462737]
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Last updated: August 18, 2025