New Study Challenges “Late-Onset ADHD”


The American Journal of Psychiatry has just published an article challenging the notion of “late-onset ADHD.” The researchers were led by Margaret H. Sibley at Florida International University. The researchers found that 95% of adolescents and adults who screened positive for late-onset ADHD did not merit the actual diagnosis. That is, out of every 100 adults identified by questionnaires as positive for ADHD, only 5 people actually meet criteria for the diagnosis.

“Individuals seeking treatment for late-onset ADHD may be valid cases,” Sibley writes. “However, more commonly, symptoms represent nonimpairing cognitive fluctuations, a comorbid disorder, or the cognitive effects of substance use.”

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They add that “among individuals with impairing late-onset ADHD symptoms, the most common reason for diagnostic exclusion was symptoms or impairment occurring exclusively in the context of heavy substance use.” That is, the supposed ADHD symptoms were actually due to the participant being impaired by substance use.

Of the few cases that did meet criteria for ADHD, almost all of them appeared in adolescence. The researchers write that “there was no evidence for adult-onset ADHD independent of a complex psychiatric history.”

The researchers note that this finding applies to adolescents and adults who do not have a childhood history of ADHD. That is, children with an ADHD diagnosis may still meet criteria for the diagnosis as adults. However, the researchers suggest that their work challenges the theory that ADHD can suddenly show up in adolescence or adulthood.

The study was part of the Multimodal Treatment Study of Children with ADHD (MTA), a large, long-running study on ADHD. The MTA is a commonly cited study on ADHD, whose findings have also demonstrated a lack of long-term efficacy for psychostimulant medications. The study included 239 children (on average, 10 years old) who did not have the ADHD diagnosis, and assessed them repeatedly for ADHD until they were young adults (on average, 25 years old). Assessments included self-report, parent report, and teacher report of behavior, as well as substance use and other contextual factors.

Sibley and her colleagues conclude that “false positive late-onset ADHD cases are common without careful assessment.”

Sibley notes that “adolescents and young adults without childhood attention deficit hyperactivity disorder (ADHD) often present to clinics seeking stimulant medication for late-onset ADHD symptoms.” In that context, it is vital that clinicians learn how to distinguish those who are abusing substances and who do not meet criteria for ADHD, even when screening positive.

The researchers suggest that screening questionnaires substantially increase the likelihood of overdiagnosis and that the prevalence of late-onset ADHD has been overestimated in the research literature for this reason. Instead, it is likely that very few adults actually meet criteria for the diagnosis of ADHD if they did not already have a history of ADHD as a child.

Sibley’s final advice?

“Clinicians should carefully assess impairment, psychiatric history, and substance use before treating potential late-onset cases.”



Sibley, M. H., Rohde, L. A., Swanson, J. M., Hechtman, L. T., Molina, B. S. G., Mitchell, J. T. . . . Stehli, A. (2018). Late-onset ADHD reconsidered with comprehensive repeated assessments between ages 10 and 25. American Journal of Psychiatry, 175(2), 140-149. (Link)


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  1. So first psychiatry invented childhood ADHD to lure parents into continually sedating rather than raising their healthy kids, who thus never develop the mature coping skills needed to become self-sufficient adults. Then it invented “late-onset ADHD” to offer legal speed to teens/adults who aren’t already hooked on psychiatry’s drugs. An entire profession of lying, scamming drug dealers has managed to gain prestige and riches by giving us epidemics of heroin overdosing, mass shootings, etc.

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    • But we never hear about how the “mental health” industry grooms people for future addictions or debilitates otherwise healthy people with periods of extended use of drugs that have never been studied long term. Nor do we bring up the fact that 2 generation have now been conceived in mothers who were told that anti-depressants and benzos are “safe”. This is an entrenched and government supported criminal enterprise that has rewritten human history for at least the short term.

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  2. I’m surprised this got published. Do I detect a little integrity at an academic institution? Let’s watch the push back. Florida International University will not get future federal funding. Margaret H. Sibley will get sacked. If she has tenure, she will not be asked to serve as a keynote speaker at future APA conferences or present her paper at gala events sponsored by big Pharma companies.

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    • But notice that it still supports the idea that childhood ADHD is a valid and real thing.

      ADHD and ADD are totally bogus as far as I’m concerned, for anyone. I taught fifteen years and never dealt with a student that I’d label with something like this. As a student myself I never, in my twelve years of schooling, ever ran across a fellow student who could have been labeled with this. It didn’t even exist until the late 1980’s when all of a sudden it cropped up out of nowhere. I’ve never understood why Americans are so convinced that this is a real thing. And I’ve never understood why American parents are so willing to drug their kids with legal speed. How in the hell does anyone think that giving kids speed is a good thing???? What ends up happening is that we stunt the physical and emotional and psychological growth of kids by doing this to them and in the end the drugged kids do no better in school and are no more attentive than their lucky classmates who managed to duck getting the horrible label. Teachers are one of the largest groups who advocate for labeling a child with this bull manure, along with school psychologists.

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  3. Every little bit of data helps. Nibble away at the clinical practices, subject prescribing practices to scrutiny, expose the ridiculousness and subjectivity of the routine diagnostic rituals to the public, one person at a time

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  4. I still don’t understand how anyone can claim “overdiagnosis” or “misdiagnosis” of something that has no objective diagnostic criteria. It’s good they recognize that “Adult ADHD” is a marketing scheme, but how is it any different than “childhood ADHD,” which they still claim to be able to diagnose accurately?

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  5. my personal guess is that we’re swinging back towards a more careful use of uppers by prescription, and this study is part of a shift from viewing speed as “necessary medication” back towards “Schedule II controlled substance with high abuse potential.”

    I do not think this means psychiatry, as a whole, or psychiatrists, individually, have suddenly developed a conscience. Far from it. Psychiatric diagnoses, treatment, outlook, etc. shift based on dogma, social changes, economic changes, and this is probably just a result of the anti-fun pills (for -most- people…) environment that we now live in. If you’ll notice, pain killers are now regarded with suspicion, and Xanax is being scrutinized, also. My guess is that this sort of study helps psychiatry seem “scientific,” and also puts Mental Health, Inc. in a position in which they can look as if they’re somehow “helping,” rather than facing judgment as ruthless, pseudoscientific drug pushers.

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  6. Steve and Yeah I Survived are both right. We should not be breaking out the champagne bottles because of this one critical study. Primary care physicians are still the number one on-ramp for receiving an ADHD diagnosis. For that reason alone, The Journal of Psychiatry can afford to publish this study because, after all, psychiatry can point fingers and say, “We did not create this over-prescribing problem, pediatricians and primary care providers did!” In fact, one could argue, the publication of this study in a journal dedicated to PSYCHIATRY is likely to have far less impact on prescribing for ADHD than if it had been published in a journal for pediatricians. Still, some readers of this article may be start to develop a healthy skepticism. Maybe some parents, upon reading this article may be more inclined to ask their doctors some tough questions, such as do they tend to believe or be influenced by the rubbish in the medical literature that passes for ‘science’? After all, readers can’t help but wonder what kind of marketing went into this epidemic of getting children hooked on clean meth?

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