As seen in Psychology Today.

For many years, attention deficit/hyperactivity disorder (ADHD) was typically thought of as a condition that affected children and adolescents and remitted as they grew older, but there has been a notable increase in ADHD diagnoses in adults recently. Why is that?

ADHD is a neurodevelopmental disorder characterized by a pattern of inattention, difficulties with impulse control, hyperactivity, and an inability to maintain concentration, which can interfere with academic, social, or occupational functioning.

ADHD presents in one of three ways:

  • Predominately inattentive
  • Predominately hyperactive or impulsive
  • Combined inattentive and hyperactive or impulsive

Is ADHD New?

No. While the diagnosis of ADHD was formally adopted in 1987 with the publication of the revision to the third edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-III-R), the disorder is not a recent phenomenon. The core features of the condition were described as early as 1798 by the Scottish physician Sir Alexander Crichton; the first report on the efficacy of stimulant medication to treat symptoms of ADHD in children was published in 1937; and the publication of the DSM-II in 1968 included a section on “hyperkinetic reaction of childhood (or adolescence),” which has since become ADHD.

Is ADHD Becoming More Common?

Regardless of age, more patients are being diagnosed with ADHD. The National Health Interview Survey estimated the prevalence in children aged 4 to 17 years to be around 6 percent in the 1990s, but that figure had climbed to approximately 10 percent by 2016. There is no indication that this trend has reversed. In fact, figures from the Centers for Disease Control and Prevention reveal that ADHD has recently been diagnosed in 2 percent of children aged 3 to 5 years, 10 percent of children aged 6 to 11 years, and 13 percent of children aged 12 to 17 years.

Though more individuals are being diagnosed with ADHD, few people would argue that it is becoming more common. Rather, the rise seems to be due to an increase in access to healthcare; a decrease in stigmatization about receiving mental health care; and greater awareness of the symptoms of ADHD among clinicians, guardians, educators, and patients. In the past, ADHD was only diagnosed in children who were hyperactive. In recent years, more attention has been given to symptoms associated with inattention, which has also led to a rise in the number of people diagnosed with the disorder—particularly girls, who present with the inattentive subtype more often than the hyperactive subtype.

Can Adults Be Diagnosed with ADHD?

Yes. ADHD does not resolve once a patient turns 18 or graduates high school. Researchers have recognized that ADHD symptoms persist into adulthood for as many as 60 percent of those who were diagnosed with the disorder during childhood. Recognition of this fact may explain the 123 percent increase in ADHD prevalence among adults reported between 2007 and 2016 (from 0.43 percent to 0.96 percent).

Rather than symptoms disappearing as one grows older, they may manifest in new ways, with symptoms of hyperactivity and impulsivity tending to become less overt. A predominately hyperactive child who is unable to remain in their seat for the duration of a short cartoon may grow into an adult who finds themselves fidgeting throughout a film. A predominately impulsive child who talks over others or acts without thinking may mature into an adult who monopolizes conversations, finds it impossible to stick to a budget, or engages in risky behaviors that frequently lead to accidents and injuries.

More frequently, symptoms that can affect attention and executive functioning persist well into adulthood without significant changes, meaning patients may exhibit an inability to focus, plan, organize, manage time, prioritize tasks, and make decisions—what people now call “adulting”. This can lead not only to academic underachievement following high school, but career problems and difficulties with financial responsibilities or maintaining relationships. If you are struggling with these kinds of problems, you may have ADHD.

If you sometimes get distracted because of a notification from an app on your phone and then suddenly find yourself, many minutes later, still staring at the screen, you probably don’t have ADHD. What you have is an attention-seeking machine in your pocket that is designed to distract you and monopolize your gaze. This is coupled with a media ecosystem where every political or celebrity-related event needs to be sensationalized and converted into clickbait. Since every second that you are working, sleeping, or socializing translates into potential lost revenue for someone, billions are spent devising novel ways to grab your attention and keep you engaged.

In other words, if you can’t stop looking at your phone, it’s only proof that you are susceptible to sophisticated technologies meant to hijack your attention—not evidence that you have ADHD.

Is Adult-Onset ADHD Possible?

It is possible for adults to develop symptoms that present as ADHD, but it is uncommon for these symptoms to appear without a history of ADHD. As noted before, the prevalence of ADHD has likely remained static, even if the rate of diagnosis has increased since the end of the last century. Consequently, it is possible that some individuals may have had mild cases of ADHD while children went undiagnosed because there was no need to seek psychiatric care. Still others may have had symptoms that were below the threshold for a diagnosis of ADHD or were included as part of another disorder, like oppositional defiant disorder. The ADHD symptoms (particularly inattention) may have then become more pronounced later in life, possibly following a stressful life event.

There is no question that adults can have ADHD. However, it’s important to distinguish between ADHD-like symptoms that are likely caused by stress and ADHD itself, which has its own unique pathophysiology. For patients who have no history of ADHD or any other related illness but complain of an inability to concentrate and stay on task, clinicians should encourage them to engage in stress mediation techniques, eat a balanced diet, exercise, avoid social media, and get a good night’s sleep. If these interventions don’t work, only then should the possibility of adult ADHD be considered.