Attention deficit hyperactivity disorder (ADHD) is often considered a childhood disorder that diminishes in adulthood. But it can also be diagnosed in adults.
In the United States, 15.5 million adults have been diagnosed with ADHD or attention deficit/hyperactivity disorder. More than half who received their diagnosis in adulthood experience symptoms that include trouble paying close attention to details, sustaining attention, following instructions, forgetfulness, talking excessively and/or interrupting.
“There used to be an old saying that people who had ADHD would grow out of it,” explains clinical psychologist Patrick Moran. “I think what really happened is that they would learn compensatory coping skills so that they could do some of the downregulation with their emotions and behaviors. In essence, they just got better at managing it, so it was less obvious to the external observer.”
A Challenging Diagnosis
The prevalence of ADHD diagnoses has increased, but the tendency for symptoms to overlap with depression, anxiety and other psychiatric disorders means that it is often misdiagnosed and, as a result, inadequately treated.
Moreover, Moran notes, “Most of the research over the years has been focused on kids, and so a lot of the materials that we've developed have had a very pediatric orientation to them and it took a while for the field to begin to hone in on developing those kinds of rating scales and other neurocognitive measures for adults.”
The right assessments are critical for diagnosing ADHD, ruling out other conditions that can masquerade as ADHD, providing a deeper understanding of individual symptoms and developing an effective treatment plan.
A comprehensive evaluation for ADHD in adults often includes the Delis Rating of Executive Functions, Adult (D-REF Adult), Brown Executive Function/Attention Scales ™, and cognitive or
neuropsychological tests such as the Wechsler Memory Scale ® (WMS ®) or the Delis-Kaplan Executive Function System ™ (D-KEFS ™).
“In adults, we’re going to see ADHD impacting executive functioning: how we organize ourselves, how we approach problem-solving, how we maintain attention and whether we have a level of cognitive flexibility to pivot to new information without losing critical aspects of the prior information…and when anomalies come in, are we able to adapt?” he says. “Neuropsychological tests tap into this well.”
The WAIS-5 and ADHD in Adults
Clinicians also use the Wechsler Adult Intelligent Scale ® (WAIS), the most popular cognitive assessment for adults, when assessing adults for ADHD. Although the WAIS ® -5 isn’t used to render a diagnosis of ADHD, it can help to rule out competing differential diagnoses, including low cognitive ability, low working memory, or slowed processing speed.
The WAIS test results for verbal working memory and processing speed have also been used as indicators of the severity of ADHD.
“It’s not predictive but we might see correlates of working memory and processing speed on the WAIS-5,” says Moran. “I like to think of it not as the defining diagnostic tool, but as an early indicator of some information processing difficulties they may have, and if we have lower scores with working memory and processing speed, then we follow up with additional testing to gain more specific information about how they are processing information.”
Issues with working memory are a hallmark of adult ADHD, according to Moran. The WAIS-5 measures auditory and visual working memory, offering a greater capacity to measure the nuances of working memory than previous versions. The assessment may also provide insights into processing speed and cognitive functioning to help characterize the clinical presentation
“Part of what we can do with WAIS-5 is differentially diagnose whether there is a core problem that affects ways of processing information or is primarily a problem with auditory or visual working memory,” he says. “A cognitive test like the WAIS-5 gives us a nice backdrop of overall cognitive abilities and gives a good indicator of information processing hurdles.”
Choosing the right assessments to diagnose adult ADHD is key for evaluating baseline functioning and how behaviors are manifesting in the real world before starting a medication trial and comparing it to the results once treatment is initiated. Moran adds, “It allows us to actually see some changes in how people process information when they're appropriately treated with the right cognitive therapy and medication.”