What Is Adult ADHD?
Attention deficit hyperactivity disorder (ADHD) is well recognized in children and adolescents, and is increasingly being recognized in adults. The labels used to describe this cluster of problems have changed many times over the past 100 years, but currently attention deficit disorder (ADD) and attention deficit hyperactivity disorder (ADHD) are the most commonly used diagnostic terms. As with most psychiatric disorders, the causes of ADHD are not fully understood, but the condition is thought to be due to a combination of genetic factors, prenatal exposures, and life experiences. Symptoms of ADHD lead to poorer performance, particularly at school and work, than would be expected.
Attention deficit hyperactivity disorder is defined as a neurodevelopmental disorder in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). ADHD includes primarily problems with inattention and/or hyperactivity. However, because inattention and hyperactive behavior affect emotions and relationships with others, the impact of ADHD can be broad and pervasive. The problems with attention and/or hyperactivity start in childhood, but for many people, these continue into adulthood too. In order to be diagnosed with ADHD, an adult must have a history of symptoms that start during childhood. The DSM-5 requires the presence of symptoms before the age of 12, since recall of symptoms earlier in life is difficult or impossible to reliably establish. Therefore, by definition, there can't be a diagnosis of adult-onset ADHD.
A recent study suggested that there may actually be a different type of ADHD that starts in adulthood. However, this finding is quite controversial and contrary to currently accepted diagnosis and treatment recommendations. A second study was published shortly after this one and argued that diagnoses of adult-onset ADHD are actually better explained by substance use disorders, sleep disorders, and other conditions that can impair attention.
It is important to recognize that inattention due to ADHD does not affect all areas in someone's life equally. When people with ADHD are involved in an area that naturally holds their interest, they may pay attention as well as, or nearly as well as, others. However, when tasks are repetitive or hold less interest for that person, these individuals often experience greater difficulty maintaining focus and remaining on task. Because of this, those with ADHD may be prone to procrastination, and their behavior may be perceived as immature or inappropriate.
As children with ADHD grow up, their overtly hyperactive-impulsive qualities often diminish, while the inattentive and disorganized patterns of behavior tend to persist. Adults with ADHD often fit this pattern: inattention, disorganization, and low tolerance of frustration or boredom, combined with the childhood history of inattention and hyperactivity. In adults, inattention tends to cause the most impairment and problems.
Compared with unaffected people, those with ADHD often require more practice over longer periods of time to develop effective habits and behavior. These issues can result in complications in many aspects of life, including school or job achievement, performance in athletic activities, driving, as well as success in relationships, specifically friendships, dating, and marriage.
The acceptance of adult ADHD has changed dramatically over the last 20 years. Based on accepted knowledge at the time, the DSM-IV indicated that most adolescents and adults outgrew ADHD and did not have persistent symptoms as adults. More recently, however, it is thought that 60%-70% of adults who had ADHD as children continue to have significant symptoms that cause impairment. Recent studies indicate that around 5% of children and 2%-4% of adults are affected by ADHD. Males seem to be more likely to have ADHD, with one and a half to two times as many males as females affected. When assessing adults for ADHD, it is critical to establish the presence of symptoms in childhood, and to rule out other psychiatric and non-psychiatric medical disorders that can cause attention problems (this includes mood, anxiety, and psychotic disorders; personality disorders; substance use disorders; sleep disorders; and cognitive disorders). Adults with ADHD are also at higher risk of also having other comorbid psychiatric disorders, including substance use disorders, depression, and anxiety disorders.