Adult attention deficit hyperactivity disorder (adult ADHD) is ADHD that persists into adulthood. It is a neurodevelopmental disorder, meaning impairing symptoms must have been present in childhood, except for when ADHD occurs after traumatic brain injury. According to the DSM-5 diagnostic criteria, multiple symptoms should have been present before the age of 12. This represents a change from the DSM-IV, which required symptom onset before the age of 7. This was implemented to add flexibility in the diagnosis of adults. ADHD was previously thought to be a childhood disorder that improved with age, but later research challenged this theory. Approximately two-thirds of children with ADHD continue to experience impairing symptoms into adulthood, with symptoms ranging from minor inconveniences to impairments in daily functioning, and up to one-third continue to meet the full diagnostic criteria.
This new insight on ADHD is further reflected in the DSM-5, which lists ADHD as a disorder and has distinct requirements for children and adults. Per DSM-5 criteria, children must display "six or more symptoms in either the inattentive or hyperactive-impulsive domain, or both," for the diagnosis of ADHD. Older adolescents and adults (age 17 and older) need to demonstrate at least five symptoms before the age of 12 in either domain to meet diagnostic criteria. The International Classification of Diseases 11th Revision (ICD-11) also updated its diagnostic criteria to better align with the new DSM-5 criteria, but in a change from the DSM-5 and the ICD-10, while it lists the key characteristics of ADHD, the ICD-11 does not specify an age of onset, the required number of symptoms that should be exhibited, or duration of symptoms. The research on this topic continues to develop, with some of the most recent studies indicating that ADHD does not necessarily begin in childhood.
A final update to the DSM-5 from the DSM-IV revised the way it classifies ADHD symptoms, exchanging "subtypes" for "presentations" to better represent the fluidity of ADHD features displayed by individuals across development and contexts.
Presentations Symptom manifestation and severity of ADHD vary greatly among individuals. Hyperactivity begins decreasing in adolescence. Inattention is more common than hyperactivity, manifesting as difficulty starting and completing tasks, forgetfulness, a lack of persistence, disorganization, and excessive tardiness. A combined presentation is a combination of hyperactivity, inattention, and impulsivity.
ADHD can be diagnosed only by licensed clinicians. Diagnosis is made clinically, via a comprehensive, structured interview whose purpose is to get full history of the individual's current and childhood symptoms and their negative impact on daily functioning. A complete medical history should also be obtained, because the rates of coexistent conditions (comorbidities) with ADHD are high. Supplemental history from people close to the individual in different settings, such as parents, siblings, romantic partners, teachers, coworkers, and employers, can support a diagnosis.
ADHD is a highly genetically influenced condition, meaning it commonly runs in families. Individuals with a first-degree relative with ADHD demonstrate a risk of ADHD 4-5 times higher than the general population rate and have prevalence rates of around 20%. The rate of inheriting the disorder is estimated to be about 76% among children and adolescents and between 70 and 80% among adults. The exact causes of ADHD are still not fully understood, but twin studies indicate that non-genetic biological risk factors (e.g., low birth weight, events during pregnancy) and non-shared environmental events also contribute to the development of ADHD.
Effective management of ADHD generally requires a combination of psychoeducation (teaching affected individuals about ADHD and its presentation and effects), behavioral interventions (e.g., cognitive behavioral therapy (CBT)), pharmacotherapy (treatment utilizing medication), and coaching for ADHD. Psychostimulants, or simply stimulants, are considered the first-line medication for the treatment of ADHD. Particularly for adults, amphetamines (e.g., dexamphetamine) are considered the most effective medication.
Classification ADHD presentations The Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5) categorizes ADHD into three presentations:
Predominantly Inattentive Presentation (ADHD-I) Meets criteria for inattentive but not hyperactive-impulsive presentation Predominantly Hyperactive-Impulsive Presentation (ADHD-HI) Meets criteria for hyperactive-impulsive but not inattentive presentation Combined Presentation (ADHD-C) Meets criteria for both inattentive and hyperactive-impulsive presentations ADHD-I is the most common presentation among adults, with 45% of adults with ADHD meeting criteria for the predominantly inattentive presentation. 34% of adults with ADHD meet criteria for the combined presentation (ADHD-C), and 21% of adults with ADHD meet criteria for the predominantly hyperactive-impulsive presentation (ADHD-HI).
Diagnostic criteria The DSM-5 lists 18 possible symptoms that a person may exhibit that would be consistent with a diagnosis of ADHD. There are nine inattentive symptoms and nine hyperactive-impulsive symptoms. Older adolescents and adults (age 17 and older) only need to demonstrate five symptoms in either the inattentive or hyperactive-impulsive presentation to meet the criteria for diagnosis. This differs from the required six symptoms in either presentation for children to meet diagnostic criteria.
In accordance with the updates to the DSM-5, published in 2013, the other criteria necessary for a diagnosis of ADHD in adults are as follows: Symptoms have been present for at least 6 consecutive months Symptoms do not match the individual's level of development Several symptoms onset before age 12 years Several symptoms manifest in two or more domains (e.g., home, school, work) Symptoms disrupt or diminish social, academic, and occupational performance Symptoms cannot be better explained by another psychiatric disorder
Signs and symptoms ADHD is a chronic condition, beginning in early childhood, and can persist throughout a person's lifetime. It is estimated that 33–66% 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, and disorganization. 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 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 management, 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 can lead to poor performance in school and work and can be followed by underachievement in these areas. In young adults, poor driving records with traffic violations may surface.
As problems accumulate, a negative 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.
Studies on adults with ADHD have shown that, more often than not, they experience self-stigma and depression in childhood, commonly resulting from feeling neglected and different from their peers. These problems may play a role in the high levels of depression, substance abuse, and relationship problems that affect adults with ADHD later in life.
Emotional dysregulation, or the inability to properly manage one's emotions, as demonstrated by low frustration tolerance, irritability, negative emotional outbursts, and emotional lability, has been found to be a key symptom of ADHD in all age groups. Unlike other symptoms of ADHD that tend to improve or decline with age, emotional dysregulation has been shown to be more persistent into adulthood. Despite the increasing recognition among clinicians of emotion dysregulation as a prominent symptom of ADHD, especially among adults, it is not recognized in the DSM-5 as a core symptom of ADHD for diagnostic criteria. However, the DSM-5 does include the symptoms of emotional dysregulation as "associated features" that can support the diagnosis of ADHD.
Inattentive-type (ADHD-I) Hyperactive/impulsive-type (ADHD-HI) In children: Forgetful during daily activities Easily distracted by extraneous stimuli Losing important items (e.g. pencils, homework, toys, etc.) Always asking for attention, but Not listening and not responding to names being called out Unable to focus on tasks at hand, cannot sustain attention in activities Avoids or dislikes tasks requiring sustained mental effort Makes careless mistakes by failing to pay attention to details Difficulty organizing tasks and activities Fails to follow through on complex instructions and tasks (e.g. homework, chores, etc.)In children: Squirms and fidgets (with hands and/or feet) Cannot sit still Cannot play quietly or engage in leisurely activities Talks excessively Runs and climbs excessively Always on the go, as if "driven by a motor" Cannot wait for their turn Blurts out answers Intrudes on others and interrupts conversations In adults: Avoiding tasks or jobs that require concentration Procrastination Difficulty initiating tasks Difficulty organizing details required for a task Difficulty recalling details required for a task Difficulty multitasking Poor time management, losing track of time Indecision and doubt Hesitation of execution Difficulty persevering or completing and following through on tasks Delayed stop and transition of concentration from one task to anotherIn adults: Fidgets with or taps hands or squirms in chair Has difficulty remaining seated Extreme restlessness Talks excessively Interrupts or intrudes on others Has difficulty waiting their turn Difficulty engaging in activities quietly Blurts out answers before questions have been completed
Diagnosis
Screening for ADHD in adults