Adult attention deficit hyperactivity disorder
|Attention deficit hyperactivity disorder|
Left: brain activity in healthy subjects. Right: apparent decreased brain activity in people living with ADHD. (Zametkin et al, 1990)
|Classification and external resources|
Adult attention deficit hyperactivity disorder (also referred to as adult ADHD or simply ADHD in adults, formerly AADD) is the neurobiological condition of attention deficit hyperactivity disorder (ADHD) in adults. About one-third(p44) to two-thirds of children with symptoms from early childhood continue to demonstrate notable ADHD symptoms throughout life.
Three subtypes of ADHD are identified in the DSM-IV as:
In later life, the hyperactive/impulsive subtype manifests less frequently.(p44) The hyperactivity symptoms tend to turn more into "inner restlessness", starting in adolescence and carrying on in adulthood.
Adult ADHD is typically marked by inattentiveness, difficulty getting work done, procrastination and organizational problems. Specifically, ADHD adults present persistent difficulties in following directions, remembering information, concentrating, organizing tasks, completing work within specified time frames and appearing timely in appointments. These difficulties affect several different areas of an ADHD adult's life, causing problems such as emotional, social, vocational, marital, legal, financial or academic.[unreliable medical source] As a result, low self-esteem is commonly developed.
- examination of personal history
- observational evidence from family members or close friends
- academic reports, often going back to school years
as well as evaluation to diagnose additional possible conditions which often coexist with ADHD.
The condition is highly heritable, and while its exact causes are not fully known, genetic or environmental factors are understood to play a part. ADHD is a childhood-onset condition, usually requiring symptoms to have been present before age seven for a diagnosis. Children under treatment will migrate to adult health services if necessary as they transit into adulthood, however diagnosis of adults involves full examination of their history.
Successful treatment of ADHD is usually based on a combination of medication, cognitive behavioral therapy, and coaching or skills training.[unreliable medical source] Medium-to-high intensity physical exercise, improved sleep and improved and targeted nutrition[unreliable medical source] are also known to have a positive effect. Within school and work, reasonable accommodations may be put in place to help the individual work more efficiently and productively.
The DSM-IV, or Diagnostic and Statistical Manual of Mental Disorders, 2000 edition, defines three types of ADHD:
To meet the diagnostic criteria of ADHD, an individual must display:
- at least six inattentive-type symptoms for the inattentive-type
- at least six hyperactive-type symptoms for the hyperactive/impulsive type
- all of the above to have the combined-type
The symptoms (see below) need to have been present since before the individual was seven years old, and must have interfered with at least two spheres of his or her functioning (at home and at school or work, for example) over the last six months. The DSM-IV criteria for ADHD are, however, tailored towards the type of symptoms that children would show, and might therefore underestimate the prevalence of ADHD in adults.[page needed] In 2013, the newer DSM-V reviewed some of these criteria, with more lenient requirements for the diagnosis, specially in adults.
Signs and symptoms
ADHD is a chronic condition, beginning in early childhood and persisting throughout a person's lifetime. It is estimated that up to 60% of children with ADHD will continue to have significant ADHD-related symptoms persisting into adulthood, resulting in a significant impact on education, employment, and interpersonal relationships.
Individuals with ADHD exhibit deficiencies in self-regulation and self-motivation which in turn foster problematic characteristics such as distractibility, procrastination, disorganization and misprioritization. They are often perceived by others as chaotic, with a tendency to need high stimulation to be less distracted and function effectively. The learning potential and overall intelligence of an adult with ADHD, however, are no different from the potential and intelligence of adults who do not have the disorder.
Whereas teachers and caregivers responsible for children are often attuned to the symptoms of ADHD, employers and others who interact with adults are far less likely to regard such behaviors as a symptom. In part, this is because symptoms do change with maturity; adults who have ADHD are less likely to exhibit obvious hyperactive behaviors. Instead they may report constant mental activity and inner restlessness, as their hyperactivity internalizes.
Symptoms of ADHD (see table below) can vary widely between individuals and throughout the lifetime of an individual. As the neurobiology of ADHD is becoming increasingly understood, it is becoming evident that difficulties exhibited by individuals with ADHD are due to problems with the parts of the brain responsible for executive functions (see below: Pathophysiology). These result in problems with sustaining attention, planning, organization, prioritization, time blindness, impulse control and decision making.
The difficulties generated by these deficiencies can range from moderate to extreme, resulting in the inability to effectively structure their lives, plan daily tasks, or think of and act accordingly even when aware of potential consequences. These lead to poor performance in school and work, followed by underachievement in these areas. In young adults, poor driving record with traffic violations as well as histories of alcoholism or substance abuse may surface. The difficulty is often due to the ADHD person's observed behaviour (e.g. the impulsive types, who may insult their boss for instance, resulting in dismissal), despite genuinely trying to avoid these and knowing that it can get them in trouble. Often, the ADHD person will miss things that an adult of similar age and experience should catch onto or know. These lapses can lead others to label the individuals with ADHD as "lazy" or "stupid" or "inconsiderate".
As problems accumulate, a negativistic self-view becomes established and a vicious circle of failure is set up. Up to 80% of adults may have some form of psychiatric comorbidity such as depression or anxiety. Many with ADHD also have associated learning disabilities, such as dyslexia, which contributes to their difficulties.
|Inattentive-type (ADHD-PI)||Hyperactive/Impulsive-type (ADHD-PH)|
|In adults, these evolve into:
The diagnosis of ADHD in adults requires retrospectively establishing whether the symptoms were also present in childhood, even if not previously recognized. As with other mental disorders such as schizophrenia there is no objective "test" that diagnoses ADHD. Rather, it is a combination of a careful history of symptoms up to early childhood, including corroborating evidence from family members, previous report cards, etc. The screening tests also seek to rule out other conditions or differential diagnoses such as depression, anxiety, or substance abuse. Other diseases such as hyperthyroidism may exhibit symptoms similar to those of ADHD, and it is imperative to rule these out as well. Asperger syndrome, a condition on the autism spectrum, is sometimes mistaken for ADHD, due to impairments in executive functioning found in some people with Asperger syndrome. However, Asperger syndrome also typically involves difficulties in social interaction, restricted and repetitive patterns of behavior and interests, and problems with sensory processing, including hypersensitivity.
Assessment of adult patients seeking a possible diagnosis can be better than in children due to the adult's greater ability to provide their own history, input, and insight. However, it has been noted that many individuals, particularly those with high intelligence, develop coping strategies that mask ADHD impairments and therefore they do not seek diagnosis and treatment.[unreliable medical source?]
Formal tests and assessment instruments such as IQ tests, standardized achievement tests, or neuropsychological tests typically are not helpful for identifying people with ADHD. Furthermore, no currently available physiological or medical measure is definitive diagnostically. However, psycho-educational and medical tests are helpful in ruling in or out other conditions (e.g. learning disabilities, mental retardation, allergies) that may be associated with ADHD-like behaviors.
United States medical and mental health professionals follow the Diagnostic and Statistical Manual of Mental Disorders (DSM) of the American Psychiatric Association; the International Classification of Diseases (ICD) published by the World Health Organisation (WHO) is often used by health professionals elsewhere. Periodic updates incorporate changes in knowledge and treatments.[unreliable medical source] For example, under DSM-IV (published in 1994, with corrections and minor changes in 2000), the diagnostic criteria for ADHD in adults broadly follow the same as in children, but the proposed revision for the DSM-5 differentiates the presentation of ADHD for children and adults for several symptoms.
It should be noted that every normal individual exhibits ADHD-like symptoms occasionally (when tired or stressed, for example) but for a positive diagnosis to be received, the symptoms should be present from childhood and persistently interfere with functioning in multiple spheres of an individual's life: work, school, and interpersonal relationships. The symptoms that individuals exhibit as children are still present in adulthood, but manifest differently as most adults develop compensatory mechanisms to adapt to their environment.
Over the last 30 years, research into ADHD has greatly accelerated. There is no single, unified theory that explains the cause of ADHD and research is ongoing. Genetic and environmental factors are thought to play a part.
It is becoming increasingly accepted that individuals with ADHD have difficulty with "executive functioning". In higher organisms, such as humans, these functions are thought to reside in the frontal lobes. They enable recall of tasks that need accomplishing, organization to accomplish these tasks, assessment of consequences of actions, prioritization of thoughts and actions, keeping track of time, awareness of interactions with surroundings, the ability to focus despite competing stimuli, and adaptation to changing situations.
Several lines of research based on structural and/or functional imaging techniques, stimulant drugs, psychological interventions have identified alterations in the dopaminergic and adrenergic pathways of individuals with ADHD. In particular, areas of the prefrontal cortex appear to be the most affected. Dopamine and norepinephrine are neurotransmitters playing an important role in brain function. The uptake transporters for dopamine and norepinephrine are overly active and clear these neurotransmitters from the synapse a lot faster than in normal individuals. This is thought to increase processing latency and salience, and diminished working memory.
Treatment for adult ADHD may combine medication and behavioral, cognitive, or vocational interventions. Treatment often begins with medication selected to address the symptoms of ADHD, along with any comorbid conditions that may be present. Medication alone, while effective in correcting the physiological symptoms of ADHD, will not address the paucity of skills which many adults will have failed to acquire because of their ADHD (e.g., one might regain ability to focus with medication, but skills such as organizing, prioritizing and effectively communicating have taken others time to cultivate).
Stimulants, the first line medications in adult ADHD are typically formulated in immediate and long-acting formulations.
Methylphenidate, a stimulant, with short and long-acting formulations, is often the first-line therapy and appears effective. In the short term, methylphenidate is well tolerated. However, long term studies have not been conducted in adults and concerns about increases in blood pressure have not been established. Methylphenidate increases concentrations of dopamine and norepinephrine in the synaptic cleft, promoting increased neurotransmission. It acts to block the dopamine and norepinephrine reuptake transporters, thus slowing the removal at which these neurotransmitters are cleared from the synapses.
Amphetamine and its derivatives, prototype stimulants, are likewise available in immediate and long-acting formulations. Amphetamines act by multiple mechanisms including reuptake inhibition, displacement of transmitters from vesicles, reversal of uptake transporters and reversible MAO inhibition. Thus amphetamines actively increases the release of these neurotransmitters into the synaptic cleft. They may have a better side-effect profile than methylphenidate cardiovascularly and potentially better tolerated.
The non-stimulant atomoxetine (Strattera), is also an effective treatment for adult ADHD. Although atomoxetine has a half life similar to stimulants it exhibits delayed onset of therapeutic effects similar to antidepressants. Unlike the stimulants which are controlled substances, atomoxetine lacks abuse potential. It is particularly effective for those with the predominantly inattentive concentration type of attention deficit due to being primarily a norepinephrine reuptake inhibitor. It is often prescribed in adults who cannot tolerate the side effects of amphetamines or methylphenidate. It is also approved for ADHD by the US Food and Drug Administration. A rare but potentially severe side effect includes liver damage and increased suicidal ideation.
Bupropion and desipramine are two antidepressants that have demonstrated some evidence of effectiveness in the management of ADHD particularly when there is comorbid major depression, although antidepressants have lower treatment effect sizes.
Treatment of adult ADHD may also include forms of stress management or relaxation training.
Research has shown that, alongside medication, psychological interventions in adults can be effective in reducing symptomatic deficiencies. Emerging evidence suggests a possible role for cognitive behavioral therapy (CBT) alongside medication in the treatment of adult ADHD.
For most adults, the psychosocial therapy is not effective. For this reason, medications are the first line of therapies. The medications that are prescribed for adults come in both stimulant and non-stimulant form. Although the drug therapies are effective for adults, the benefits should be discussed with the patient’s physician to ensure the benefits of the medications outweigh the risk. If medication is unwanted or not an option, increasing exercise and changing one’s diet may help alleviate some of the symptoms such as hyperactivity.
In North America and Europe, it is estimated that three to five percent of adults have ADHD, but only about ten percent of those have received a formal diagnosis.[non-primary source needed][non-primary source needed] It has been estimated that 5% of the global population has ADHD (including cases not yet diagnosed). In the context of the World Health Organization World Mental Health Survey Initiative, researchers screened more than 11,000 people aged 18 to 44 years in ten countries in the Americas, Europe and the Middle East. On this basis they estimated the adult ADHD proportion of the population to average 3.5 percent with a range of 1.2 to 7.3 percent, with a significantly lower prevalence in low-income countries (1.9%) compared to high-income countries (4.2%). The researchers concluded that adult ADHD often co-occurs with other disorders, and that it is associated with considerable role disability. Although they found that few adults are treated for ADHD itself, in many instances treatment is given for the co-occurring disorders.[non-primary source needed]
In the 1970s researchers began to realize that the condition now known as ADHD did not always disappear in adolescence, as was once thought. At about the same time, some of the symptoms were also noted in many parents of the children under treatment. The condition was formally recognized as afflicting adults in 1978, often informally called adult ADD, since symptoms associated with hyperactivity are generally less pronounced.[unreliable medical source]
Early work on disorders of attention was conducted by Alexander Crichton in 1798 writing about "mental restlessness". The underlying condition came to be recognized from the early 1900s by Sir George Still. Efficacy of medications on symptoms was discovered during the 1930s and research continued throughout the twentieth century. ADHD in adults began to be studied from the early 1970s and research has increased as worldwide interest in the condition has grown.
Society and culture
ADHD in adults, as with children, is recognized as an impairment that may constitute a disability under U.S. federal disability nondiscrimination laws, including such laws as the Rehabilitation Act of 1973 and the Americans With Disabilities Act (ADA, 2008 revision), if the disorder substantially limits one or more of an individual's major life activities. For adults whose ADHD does constitute a disability, workplaces have a duty to provide reasonable accommodations, and educational institutions have a duty to provide appropriate academic adjustments or modifications, to help the individual work more efficiently and productively.
In a 2004 study it was estimated that the yearly income discrepancy for adults with ADHD was $10,791 less per year than high school graduate counterparts and $4,334 lower for college graduate counterparts. The study estimates a total loss in productivity in the United States of over $77 billion USD.[unreliable medical source] By contrast, loss estimations are $58 billion for drug abuse, $85 billion for alcohol abuse and $43 billion for depression.[unreliable medical source]
- Anastopoulos, Arthur D.; Shelton, Terri L. (31 May 2001). Assessing attention-deficit/hyperactivity disorder. Topics in Social Psychiatry. New York: Kluwer Academic/Plenum Publishers. ISBN 978-0-306-46388-4. OCLC 51784126.
- Hechtman, Lily (8 February 2009). "ADHD in Adults". In Brown, Thomas E. ADHD Comorbidities: Handbook for ADHD Complications in Children and Adults (1st ed.). Washington, DC: American Psychiatric Publishing. p. 87. ISBN 9781585628339. OCLC 701833161.
- Kooij, SJ; Bejerot, S; Blackwell, A; Caci, H; Casas-Brugué, M; Carpentier, PJ; Edvinsson, D; Fayyad, J; Foeken, K; Fitzgerald, M; Gaillac, V; Ginsberg, Y; Henry, C; Krause, J; Lensing, MB; Manor, I; Niederhofer, H; Nunes-Filipe, C; Ohlmeier, MD; Oswald, P; Pallanti, S; Pehlivanidis, A; Ramos-Quiroga, JA; Rastam, M; Ryffel-Rawak, D; Stes, S; Asherson, P (3 September 2010). "European consensus statement on diagnosis and treatment of adult ADHD: The European Network Adult ADHD". BMC Psychiatry 10: 67. doi:10.1186/1471-244X-10-67. PMC 2942810. PMID 20815868.
- "Attention Deficit Hyperactivity Disorder: ADHD in Adults". WebMD.
- ADDitude Magazine; - Attention Deficit > ADD Symptoms & Statistics Is it ADHD? Checklist of 18 ADHD Symptoms Do you have ADD?
- Faraone, Stephen V.; Biederman, Joseph; Spencer, Thomas; Wilens, Tim; Seidman, Larry J.; Mick, Eric; Doyle, Alysa E. (July 2000). "Attention-deficit/hyperactivity disorder in adults: an overview". Biological Psychiatry 48 (1): 9–20. doi:10.1016/S0006-3223(00)00889-1. Retrieved 22 March 2013.
- DuPaul, George J. (2004). "ADHD Identification and Assessment: Basic Guidelines for Educators" (PDF). In Canter, Andrea S.; Paige, Leslie Z.; Roth, Mark D.; Romero, Ivonne; Carroll, Servio A. Helping Children at Home and School II: Handouts for Families and Educators. Bethesda, MD: NASP Publications. pp. S8–17–S8–19. ISBN 0-932955-82-7. Retrieved 19 February 2015.
- Rettew, David C.; Hudziak, James J. (2009). "Genetics of ADHD". In Brown, Thomas E. ADHD Comorbidities: Handbook for ADHD Complications in Children and Adults (1st ed.). Washington, DC: American Psychiatric Publishing. p. 32. ISBN 978-1-58562-158-3. OCLC 244601824.
- You've Got Adult ADD… Now What?, ADDitude magazine, 2007
- Newmark, Sandy. "The ADHD Food Fix: Fight Symptoms with Diet and Nutrition". ADDitudemag.com. Retrieved 12 March 2015.
- Curatolo P, D'Agati E, Moavero R (2010). "The neurobiological basis of ADHD". Ital J Pediatr 36 (1): 79. doi:10.1186/1824-7288-36-79. PMC 3016271. PMID 21176172.
- Division of Human Development, National Center on Birth Defects and Developmental Disabilities (29 September 2014). "Attention-Deficit / Hyperactivity Disorder (ADHD): Symptoms and Diagnosis". Centers for Disease Control and Prevention.
- Gentile, J. P.; Atiq, R.; Gillig, P. M. (2006). "Adult ADHD: Diagnosis, Differential Diagnosis, and Medication Management". Psychiatry (Edgmont (Pa. : Township)) 3 (8): 25–30. PMC 2957278. PMID 20963192.
- Valdizán, JR; Izaguerri-Gracia, AC (27 February 2009). "Trastorno por deficit de atencion/hiperactividad en adultos" [Attention deficit hyperactivity disorder in adults]. Revista de neurologia (in Spanish) 48 (Suppl 2): S95–9. PMID 19280582.
- Stanford, Clare; Tannock, Rosemary (29 February 2012). Behavioral Neurobiology of Attention Deficit Hyperactivity Disorder and Its Treatment. Springer. pp. 10–. ISBN 978-3-642-24611-1.
- Katragadda, S; Schubiner, H (June 2007). "ADHD in Children, Adolescents, and Adults". Primary Care: Clinics in Office Practice 34 (2): 317–341. doi:10.1016/j.pop.2007.04.012. PMID 17666230.
- Eden, GF; Vaidya, CJ (2008). "ADHD and developmental dyslexia: two pathways leading to impaired learning.". Annals of the New York Academy of Sciences 1145: 316–27. doi:10.1196/annals.1416.022. PMID 19076406.
- van Os J, Kapur S (August 2009). "Schizophrenia". Lancet 374 (9690): 635–45. doi:10.1016/S0140-6736(09)60995-8. PMID 19700006.
- National Institutes of Health (November 16–18, 1998). "Diagnosis and Treatment of Attention Deficit Hyperactivity Disorder" (PDF). Consensus Statement (NIH) 16 (2): 1–37.
- Kubose, Shauna (February 2000). "ADHD in Adults: Are the current Diagnostic Criteria Adequate?". NeuroPsychiatry Reviews (Parsippany, NJ: Quadrant HealthCom Inc.) 1 (1). Archived from the original on 7 June 2008.
- Moon, Kathryn F. (2004). "Development of the DSM". The History of Psychiatric Classification: From Ancient Egypt to Modern America (A Website composed for the History of Psychology (PSYC 6180) The University of Georgia). Archived from the original on 6 June 2009.
- Kieling, Christian; Kieling, Renata R.; Rohde, Luis Augusto; Frick, Paul J.; Moffitt, Terrie; Nigg, Joel T.; Tannock, Rosemary; Castellanos, Francisco Xavier (January 2010). "The age at onset of attention deficit hyperactivity disorder". Am J Psychiatry 167 (1): 14–6. doi:10.1176/appi.ajp.2009.09060796. PMID 20068122.
- "314.0x Attention Deficit/Hyperactivity Disorder: Proposed Revision". DSM-5 Development. American Psychiatric Association. 20 May 2010. Archived from the original on 4 December 2010.
- Hodgkins, Paul; Arnold, L. Eugene; Shaw, Monica; Caci, Hervé; Kahle, Jennifer; Woods, Alisa G.; Young, Susan (18 January 2012). "A systematic review of global publication trends regarding long-term outcomes of ADHD". Frontiers in Psychiatry 2: 84. doi:10.3389/fpsyt.2011.00084. PMC 3260478. PMID 22279437.
- Antshel KM, Hargrave TM, Simonescu M, Kaul P, Hendricks K, Faraone SV (2011). "Advances in understanding and treating ADHD". BMC Medicine 9: 72. doi:10.1186/1741-7015-9-72. PMC 3126733. PMID 21658285.
- Madras, Bertha K.; Miller, Gregory M.; Fischman, Alan J. (March 2002). "The dopamine transporter: relevance to attention deficit hyperactivity disorder (ADHD)". Behavioural Brain Research 130 (1-2): 57–63. doi:10.1016/S0166-4328(01)00439-9. Retrieved 22 March 2013.
- Bannon, Michael J. (May 2005). "The dopamine transporter: role in neurotoxicity and human disease". Toxicology and Applied Pharmacology. Membrane Transporters in Toxicology 204 (3): 355–360. doi:10.1016/j.taap.2004.08.013. PMID 15845424. Retrieved 22 March 2013.
- Searight, H. Russel; Burke, John M.; Rottnek, Fred (November 2000). "Adult ADHD: Evaluation and Treatment in Family Medicine". American Family Physician 62 (9): 2077–2086. Retrieved 22 March 2013.
- Epstein, T; Patsopoulos, NA; Weiser, M (Sep 18, 2014). "Immediate-release methylphenidate for attention deficit hyperactivity disorder (ADHD) in adults.". The Cochrane database of systematic reviews 9: CD005041. doi:10.1002/14651858.CD005041.pub2. PMID 25230710.
- Godfrey J (May 2008). "Safety of therapeutic methylphenidate in adults: a systematic review of the evidence". J. Psychopharmacol. (Oxford) 23 (2): 194–205. doi:10.1177/0269881108089809. PMID 18515459.
- Retz W, Retz-Junginger P, Thome J, Rösler M (September 2011). "Pharmacological treatment of adult ADHD in Europe". World J. Biol. Psychiatry. 12 Suppl 1: 89–94. doi:10.3109/15622975.2011.603229. PMID 21906003.
- Kolar D, Keller A, Golfinopoulos M, Cumyn L, Syer C, Hechtman L (April 2008). "Treatment of adults with attention-deficit/hyperactivity disorder". Neuropsychiatr Dis Treat 4 (2): 389–403. PMC 2518387. PMID 18728745.
- Simpson D, Plosker GL (2004). "Spotlight on atomoxetine in adults with attention-deficit hyperactivity disorder". CNS Drugs 18 (6): 397–401. doi:10.2165/00023210-200418060-00011. PMID 15089111.
- Santosh PJ, Sattar S, Canagaratnam M (September 2011). "Efficacy and tolerability of pharmacotherapies for attention-deficit hyperactivity disorder in adults". CNS Drugs 25 (9): 737–63. doi:10.2165/11593070-000000000-00000. PMID 21870887.
- Wilens, Timothy E.; Morrison, Nicholas R.; Prince, Jefferson (October 2011). "An update on the pharmacotherapy of attention-deficit/hyperactivity disorder in adults". Expert Review of Neurotherapeutics 11 (10): 1443–65. doi:10.1586/ern.11.137. PMC 3229037. PMID 21955201.
- Verbeeck W, Tuinier S, Bekkering GE. (February 2009). "Antidepressants in the treatment of adult attention-deficit hyperactivity disorder: a systematic review". Adv Ther 26 (2): 170–184. doi:10.1007/s12325-009-0008-7. PMID 19238340.
- Rösler M, Casas M, Konofal E, Buitelaar J (August 2010). "Attention deficit hyperactivity disorder in adults". World J. Biol. Psychiatry 11 (5): 684–98. doi:10.3109/15622975.2010.483249. PMID 20521876.
- Knouse LE, Safren SA (September 2010). "Current status of cognitive behavioral therapy for adult attention-deficit hyperactivity disorder". Psychiatr. Clin. North Am. 33 (3): 497–509. doi:10.1016/j.psc.2010.04.001. PMC 2909688. PMID 20599129.
- de Graaf, Ron; Kessler, Ronald C.; Fayyad, John; ten Have, Margreet; Alonso, Jordi; Angermeyer, Matthias; Borges, Guilherme; Demyttenaere, Koen; Gasquet, Isabelle; de Girolamo, Giovanni; Haro, Josep Maria; Jin, Robert; Karam, Elie G.; Ormel, Johan; Posada-Villa, José (December 2008). "The prevalence and effects of adult attention-deficit/hyperactivity disorder (ADHD) on the performance of workers: results from the WHO World Mental Health Survey Initiative". Occupational & Environmental Medicine 65 (12): 835–42. doi:10.1136/oem.2007.038448. PMC 2665789. PMID 18505771.
- Kessler, Ronald C.; Adler, Lenard; Barkley, Russell; Biederman, Joseph; Conners, C. Keith; Demler, Olga; Faraone, Stephen V.; Greenhill, Laurence L.; Howes, Mary J.; Secnik, Kristina; Spencer, Thomas; Ustun, T. Bedirhan; Walters, Ellen E.; Zaslavsky, Alan M. (April 2006). "The prevalence and correlates of adult ADHD in the United States: Results from the National Comorbidity Survey Replication". Am J Psychiatry 163 (4): 716–23. doi:10.1176/appi.ajp.163.4.716 (inactive 2015-04-13). PMC 2859678. PMID 16585449.
- Polanczyk G, de Lima MS, Horta BL, Biederman J, Rohde LA (June 2007). "The worldwide prevalence of ADHD: a systematic review and metaregression analysis". Am J Psychiatry 164 (6): 942–8. doi:10.1176/appi.ajp.164.6.942 (inactive 2015-04-13). PMID 17541055.
- Fayyad, J; De Graaf, R; Kessler, R; Alonso, J; Angermeyer, M; Demyttenaere, K; De Girolamo, G; Haro, JM; Karam, EG; Lara, C; Lépine, J-P; Ormel, J; Posada-Villa, J; Zaslavsky, AM; Jin, R (May 2007). "Cross-national prevalence and correlates of adult attention-deficit hyperactivity disorder" (PDF). Br J Psychiatry 190 (5): 402–9. doi:10.1192/bjp.bp.106.034389. PMID 17470954.
- "Adult ADHD Help Near Fort Worth, Texas". Dr. Lisa Fairweather. Fairweather Medical Group in Colleyville, Texas. Retrieved 27 October 2014.
- Berrios G.E. (2006). "Alexander Crichton and Mind in general". History of Psychiatry 17: 469–498.
- Lange, Klaus W.; Reichl, Susanne; Lange, Katharina M.; Tucha, Lara; Tucha, Oliver (30 Nov 2010). "The history of attention deficit hyperactivity disorder". Attention Deficit and Hyperactivity Disorders 2 (4): 241–55. doi:10.1007/s12402-010-0045-8. PMC 3000907. PMID 21258430.
- Ryan, Noreen; McDougall, Tim (2009). Nursing Children and Young People with ADHD. Taylor & Francis. p. 6. ISBN 9781134052196.
- ADA Division, Office of Legal Counsel (22 October 2002). "Enforcement Guidance: Reasonable Accommodation and Undue Hardship Under the Americans with Disabilities Act". The U.S. Equal Employment Opportunity Commission.
- Office of Civil Rights (25 June 2012). "Questions and Answers on Disability Discrimination under Section 504 and Title II". U.S. Department of Education.
- "Breaking News: The Social and Economic Impact of ADHD". American Medical Association. 7 September 2004. Archived from the original on 22 October 2004.
- Reinberg, Steven (9 September 2004). "Adult ADHD Costs Billions in Lost Income". HealingWell.
- "Publications About ADHD". National Institute for Mental Health. Rockville, MD.
- "Adult ADHD (attention-deficit/hyperactivity disorder)". Mayo Clinic. Mayo Foundation for Medical Education and Research.
- "AD/HD and Adults". Mental Health America. Alexandria, VA.
- "ADDA - Attention Deficit Disorder Association". Wilmington, DE.
- "ADDults with ADHD". Epping, NSW: ADDult with ADHD (NSW) Inc.
- "Home page". AADD-UK: The site for and by adults with ADHD.
- "Living with Adult ADHD". ADDitude. New York: New Hope Media LLC.
- "Attention Deficit Disorders Association: Southern Region". Houston, TX.