Zoe Kessler, a Canadian writer and performer, was diagnosed with attention deficit hyperactivity disorder at age 46. At the time, she says, her life was "falling apart" and she was desperate to figure out why.
"I was struggling financially, I'd had any number of romantic relationships gone bad, I felt socially awkward, and, working as a freelance writer, I couldn't concentrate or focus," she said in an interview. "I was so scattered. I'd stand in the middle of a room in my apartment and literally not know what I was supposed to be doing."
Kessler sought help from "psychologists, social workers, psychiatrists, previous life regression therapists and rebirthers." None of them raised the possibility of ADHD, she said.
But when a friend suggested she might have the brain disorder that is most typically associated with "little boys bouncing off the walls," she went to see her doctor.
"Not long after, I left with a prescription for stimulant medication in my hand," she said. That diagnosis and treatment radically changed her life.
And only then did it dawn on Kessler, who wrote a book about her experience, that she'd likely suffered with the condition for decades, beginning in elementary school.
ADHD, the thinking goes, generally begins in childhood. In fact, to get diagnosed with ADHD as an adult, a patient needs to demonstrate they've had traits of the condition by age 12. But new research is fueling questions about the origins and trajectory of the brain disorder.
Several reports — two population studies from the U.K. and Brazil, and an earlier study from New Zealand — suggest not only that ADHD can begin in adulthood, but also that there may exist two distinct syndromes: adult-onset ADHD and childhood ADHD.
But as it is with many issues surrounding the disorder, it's controversial and complicated.
In one of the new papers, published last month in the journal JAMA Psychiatry, researchers from King's College, London, assessed a cohort of more than of 2,000 twins born in England and Wales in the mid 1990s. They found that among those over 18 with ADHD, more than two-thirds were not diagnosed during childhood assessments. Based on that, the researchers said, two different groups emerged: "a large, late-onset ADHD group with no childhood diagnosis, and a smaller group with persistent ADHD" from childhood into late adolescence or adulthood.
They conclude that "adult ADHD is more complex than a straightforward continuation of the childhood disorder," and suggest the possibility that "childhood-onset and late-onset adult ADHD may reflect different causes."
One of the study authors, Dr. Jessica Agnew-Blais from King’s College, offers several theories on what might be driving this "late-onset" ADHD. In a statement, she said:
• The disorder could have been masked in childhood due to protective factors, such as a supportive family environment;
• It could be entirely explained by other mental health problems;
• Late-onset ADHD could be a distinct disorder altogether.
A second report similarly concludes that adult ADHD may not necessarily be a continuation of childhood ADHD. Rather, researchers say, their results "suggest the existence of 2 syndromes that have distinct developmental trajectories."
"The key message here is that … ADHD [does] not always begin in childhood," said Luis Augusto Rohde, a professor in the department of psychiatry at the Federal University of Rio Grande do Sul in Brazil, and one of the study authors, in an email.
Why does this matter?
Rohde said that for patients, it can be a crucial distinction. "The majority of clinicians worldwide are trained to only diagnose ADHD in adults when a clear history of ADHD symptoms would be detected during childhood," he said. "According to the data from the two studies, a substantial proportion of adults in the population with clear ADHD symptoms and impairments during adulthood are not receiving diagnosis and treatment."
The researchers say more study is needed to determine the nuances of the disorder. But the findings also raise provocative questions, for instance, are there treatments that might work better for adult patients, and how should clinicians evaluate adults who report no childhood history?
An editorial in JAMA Psychiatry accompanying the papers cautions about potential flaws in the studies, among them, underestimating the persistence of ADHD into adulthood and overestimating the prevalence of adult-onset ADHD. In general, the editorial authors suggest, the conclusions of the new research "seem premature."
ADHD, with its telltale traits, including inattentiveness, a need for constant movement and rash, impulsive, sometimes scattered behavior, used to be considered an illness solely of childhood. And while an understanding of ADHD has evolved to include adult sufferers, there remains controversy around the diagnosis. Some have suggested that the broader definition of ADHD was fueled, at least in part, to broaden the market for medication manufacturers; and as the criteria for the condition loosened, reports emerged about clinicians involved in diagnosing ADHD also receiving money from drug makers.
These days, much attention has focused on the very young children who are now being diagnosed with ADHD — 4-year-olds and younger — and treated with powerful medications. Earlier this year, for instance, there was public outcry when a new chewable, fruit-flavored ADHD medication hit the market.
And, of course, numerous reports have documented how the medication, aka "the good grade pill" can be abused by students and others seeking to improve test scores, focus and academic performance.
Pinpointing The Onset of ADHD
Despite all that, the conventional wisdom remains that adults with ADHD also had it as children. (If you’re wondering if you might have ADHD, the full criteria for diagnosis is on the CDC website.)
Ron Kessler -- a psychiatric epidemiologist and professor of health care policy at Harvard Medical School, and no relation to Zoe Kessler -- says much of the recent literature on adult ADHD "is just trying to figure out the nature of the beast" since it's a relatively new diagnosis.
"Nobody stands on their desks and jumps up and down as an adult like a fourth grader might," Kessler said, so it's clear the condition can look very different at different ages. Still, says Kessler: "I'd be very cautious jumping to a conclusion that says there are adults who have it who didn't have it as kids."
Based on his own research, which includes a broader view of adult ADHD that involves so-called "executive function" problems, Kessler said "it seems unlikely that out of the clear blue sky, there are all these adults who didn't have symptoms when they were young."
The lead author of the ADHD editorial, Stephen V. Faraone, with the department of psychiatry and behavioral sciences at the State University of New York Upstate Medical University, said in an interview that he's not convinced adult-onset ADHD is a distinct condition but rather that signs of the disorder were there much earlier, but missed.
"My interpretation," he said, is that the researchers involved in the recent studies, "found a group of people with sub-threshold ADHD [patients who have some characteristics of ADHD but don't meet the official criteria for a diagnosis] in their youth. There may have been signs that things weren't going too well, but they weren't bad enough to go to a doctor."
Perhaps these were smart kids with particularly supportive parents or teachers who provided the "scaffolding" needed to help the children cope with their attention problems, he says, but then, "later in life something happen[ed] to trigger full blown ADHD."
Faraone writes in the editorial, which is co-written by Joseph Biederman, M.D., of Massachusetts General Hospital:
Such intellectual and social scaffolding would help youth with ADHD to compensate in early life, only to decompensate into a full ADHD syndrome when the scaffolding is removed.
In other words, as a kid with ADHD, you may be able to get by in a supportive environment or at a school that lets you run around and learn in creative ways, but as soon as you're out on your own, trying to hold down a job with deadlines and rigid bosses and public presentations, you might unravel.
Faraone writes that "These new data are a 'call to arms' to study adult onset ADHD." He adds that for patients who think they have ADHD with no recollection of it in childhood, there are two possibilities:
--They have ADHD but it was not evident previously, perhaps due to lower level symptoms or a particularly supportive environment; or
--They have something else (e.g., an addiction, too much stress, etc….). If so, that should be treated.
Craig Surman, M.D. a neuropsychiatrist at Massachusetts General Hospital and author of a book on ADHD, "Fast Minds" (co-written by CommonHealth contributor Karen Weintraub) agrees.
"We don't have a time machine," he said in an interview, "no way of knowing what people were like as children." But, as a clinician, he says: "Most of my adult ADHD folks who meet DSM criteria are telling stories about having childhood symptoms. Yes, the impairment varies over time, but why would it be that someone in their 40s, say, suddenly has ADHD? That doesn't fit for me...There are many other diagnoses to consider with a sudden late-onset story."
'I Don't Care What We Call It'
More than a decade after her diagnosis, Kessler now uses her own ADHD as material for stand-up comedy (An example: "They say people with ADHD think outside the box. That's ridiculous. I lost the box...years ago.")
For Kessler, the question of whether there's really a separate condition known as adult-onset ADHD is more an intellectual pursuit, rather than a pragmatic one.
"Is there adult-onset ADHD? Who knows," she said. "The bottom line is I don't care what we call it — I care that we get help and support and strategies for everyone who suffered from the things I suffered from."