When a diagnosis group that is a permanent diagnosis which has been around for a while sees substantial increases in new case counts over a decade, there are several things that could be happening. None of these explanations fully exclude the alternatives.
- The underlying construct of the diagnosis is really increasing and the case counts reflect this reality.
- In the US context, obesity diagnosis codes reflect this pattern (plus value based care payment arrangements incentivezes more aggressive coding too for risk adjustment purposes
- Something changed in the measurement system that makes a lot of previously non-diagnosed but examined cases into diagnosed cases
- In the US context, state maternal mortality spikes when the definition changed
- In the US criminal justice context, some states moved a DUI threshold to a blood alcohol level of 0.08 from 0.1 which made marginal No’s into marginal Yes’s
- We have better/more specific testing so cases that were previously part of the latent construct of the diagnosis that were not being identified as such are now being identified as such.
I was thinking about this for two reasons this week. I had a chance to talk with a friend about our mutual coffee addictions. They mentioned that they recently-ish had been diagnosed with ADD as a very successful and approaching middle aged adult. Their doc had indicated that their current caffeine and former nicotine consumption patterns were likely self-medicating behavior. We both agreed that the prototypical behavior of ADHD when we were teens (red faced, almost no regulation of attention at all, wild child — almost always teen boys) who might have been on Ritalin in the 90s was not their experience. And yet, they had always felt like their brains were moving on a different pace and pattern than expectations and that these patterns made things pretty damn rough for them until they could put in a compensating system.
The other reason why I’m thinking about this is if we think that the underlying count of the construct is increasing, we would expect more of the construct elements among the young than the old. That would be good evidence to support the first case. There was a study in JAMA looking at the epidemiology of autism in England fifteen years ago:
Context To our knowledge, there is no published information on the epidemiology of autism spectrum disorders (ASDs) in adults. If the prevalence of autism is increasing, rates in older adults would be expected to be lower than rates among younger adults….
Main Outcome Measures Autism Diagnostic Observation Schedule, Module 4 in phase 2 validated against the Autism Diagnostic Interview–Revised and Diagnostic Interview for Social and Communication Disorders in phase 3. A 20-item subset of the Autism-Spectrum Quotient self-completion questionnaire was used in phase 1 to select respondents for phase 2. Respondents also provided information on sociodemographics and their use of mental health services.
Results Of 7461 adult participants who provided a complete phase 1 interview, 618 completed phase 2 diagnostic assessments. The weighted prevalence of ASD in adults was estimated to be 9.8 per 1000 (95% confidence interval, 3.0-16.5). Prevalence was not related to the respondent’s age. Rates were higher in men, those without educational qualifications, and those living in rented social (government-financed) housing. There was no evidence of increased use of services for mental health problems.
Conclusions Conducting epidemiologic research on ASD in adults is feasible. The prevalence of ASD in this population is similar to that found in children. The lack of an association with age is consistent with there having been no increase in prevalence and with its causes being temporally constant.
These findings in the English context give some substantial evidence to the third mechanism — we’re seeing a lot more diagnosis because we’re actually diagnosing the underlying construct.
AUTISM HAS ALWAYS EXISTED. Everyone I know in WV had an autistic uncle or buddy who didn’t like to talk to people and had a barn or work shed that looked like it was organized by someone who was potty trained at gunpoint with 5,000 comic books labeled on shelves in their spare rooms
— Cake or Death (@johngcole.bsky.social) April 10, 2025 at 2:24 PM
Yeah — the 40 years ago, kids who were verbal, social enough and able to present as functional-ish were never getting diagnosed except as the weird kid during the recess. That has changed dramatically over the past few decades.
Tim C
When my son was diagnosed as high-functioning autistic a few years ago, my reaction was, “No way! I mean he’s way more functional and socially aware then I was when I was……… Oh….. OH!….. ooooooooohhhhhhhhhhhhhhhhh!…. Oh.”
Phylllis
A great meme I saw went something like this: Grandma: We just didn’t have this Autism nonsense when I was young. Also Grandma: Come let me show you my 1000-piece spoon collection and explain in detail how each one is minutely different from the other 999.
Wag
100% correct. But impossible to get this point across to anyone who has bought into the MAHA bullshit.
Wapiti
Ayup. My father had multiple extensive collections (stamps, coins, insulators from powerlines, old bottles that he dug up from old privies* or town dumps, etc.)
Related, I was vacationing in Arizona recently and met a number of obsessive bird-watchers. Their hobby reminded me of my brother’s kid, who is an obsessive Magic-the-Gathering (MTG) card collector and player.
* people would drink their private stash of hootch and then throw the bottles down in the outhouse, I guess so the spouse didn’t know. Examining old town plats, a dedicated collector could guestimate where the outhouses were located on the lots…
Spanky
Ummmmmm, how does one find out if they’re on the spectrum even if they’ve been functioning quite well (hmmmm) for 70 years?
Ten Bears
They called it “hyperactive”, gave me Ritalin©™ … when I was five. Can still taste it coming off the spoon sixty-five years later: metallic crossed with static electricity. No wonder I’ve always been crazy, and it hasn’t kept me from insane
Speaking a’which: In 1957 I was a two year old Army brat when they hit me with everything they had to go to Yurp, which included early MMR (was hit again fifteen years later as a recruit). While I’m pretty ambivalent to the whole vax hoopla I really don’t appreciate high-profile people making a mockery of those of us who wonder why we are as we are … with cockamamie conspiracy theories that serve to distract from the environmental factors that impact all of us, some less some more. Prostitute themselves to Big Oil
There’s something in the water …
A woman from anywhere (formerly Mohagan)
I have self-diagnosed as being on the spectrum, although not a compulsive collector except for books LOL. I originally trained as a reference librarian and ended up as a computer programmer and analyst. My considered opinion is that most people (nerds) in IT departments are on the spectrum.
A woman from anywhere (formerly Mohagan)
@Spanky: I’m 73 and have become much better at dealing with the world, but was definitely a weird kid in school, not too good at reading social cues.
Matt McIrvin
@Spanky: I’ve been hearing that right now is NOT the time to get any kind of diagnosis– it’s painting a giant target on yourself for eugenicists and “wellness” cranks jonesing to fix you or eliminate you.
Van Buren
I don’t think I’m on the spectrum, and being a teacher and having a kid on the spectrum has given me lots of experience with kids on the spectrum, so I’m pretty confident in my self diagnosis, but oh boy am I ADD, and was ADHD until about 11th grade.
Phylllis
@A woman from anywhere (formerly Mohagan): If I had a nickel for every time I thought ‘Am I the only one who sees this pattern?’ from about age 8 on, I’d be on easy street.
Spanky
@Matt McIrvin: Yeaaaah, this is a good point
(ETA I typed out this comment, then walked away without hitting “enter”.)
BeautifulPlumage
Thank you, David. The blaming of autism on vaccines is such bullshit. As with so much the MAGAs have latched onto, neurodiversity has always existed in human populations, just like gay and transgendered folks. And as history shows, psychopaths.
I appreciate you taking the time to post this.
dnfree
@A woman from anywhere (formerly Mohagan): I agree about IT. When I discovered programming/systems analysis in the 1960s, I found my niche. It wasn’t until very recent years that I wondered about being “on the spectrum”. I think I probably am, and others in my family are, but I’m never going to go get diagnosed at my age. Interesting that there are also associations being found between ADHD and autism.
WTFGhost
Heh. It’s interesting on the other side too – not just “child to adult” but “adult to child”.
Today, it’s well known that me/CFS (usually called “just” CFS) can cause a person to have a sudden loss of capability – e.g., finding one’s reading speed has gotten very slow and error prone. Similarly, they may find their internal calculator is on the fritz.
There are children out there, who are *geniuses*. I say “like me,” and, unlike Limbaugh, I really was fighting with half my brain tied behind my back, and, I was a powerful expert in my field, when I could work.
And those kids are suddenly finding they can’t read… I mean, they *can*, but it doesn’t quite take the same way. And they still can do math, but… now they need a calculator, and it’s annoying, because they know they shouldn’t need one, until 2,3, maybe 5 significant figures (I kid… a bit).
And they probably test really well! Adrenaline, doncha know. It also makes child abuse easy, because a spanking causes adrenaline, which wakes the child up, and hence, seems to “straighten (him, usually) out.” Thing is, the adrenaline doesn’t make the child normal – it’s just a powerful stimulant that wipes away fatigue. So beatings increase, because the lesson isn’t learned with lesser beatings.
Some of these kids, I hope they make it. And some of them, I hope, reach for some stars – I bet I’d be the master electrician who could wire every single circuit in a hospital, while half-asleep, if I’d gone into electrical work. (Why “hospitals”? Think X-ray, MRI, CAT scan, bedside charging ports for every charger known to humanity, etc.. I’d feel proud that I only occasionally needed a digital calculator, rather than a slide rule and paper+memory.) Remember, some of these people are extremely bright, they just keep finding their brains malfunctioning… but only sometimes.
If they don’t reach for the stars, because they don’t understand how much they still have, even when their brains slow down, they won’t ever reach them, or even come close, and folks who fatigue easily are really best when they can work with their brains.
One thing that nearly made me cry about Gus Walz is, he knows, and his family knows, and his school knows, and, before they kill the DOE, the school needs to provide a free and appropriate public education for him. So we’re getting better.
But ain’t no one thinking that me/CFS happens in children. Well, I don’t know that I had it – I’m not a doctor, after all! Still: someday, I hope they catch kids like I was, and if they do, I bet it will probably happen while looking for Long Covid in the child population.
Obvious Russian Troll
After my wife realized she was most likely autistic, I’ve come to the conclusion that I’m probably on the spectrum as well. We’re both certain her father was autistic, and one or both of my parents may have been on the spectrum as well.
My wife is also ADHD as hell (with a formal diagnosis), and I am probably as well. I haven’t gotten a diagnosis, though, although I am debating the merits of it. (Although originally from the states I’m in Canada so RFK Jr. will have to work harder to get me in his MAHA labor camps.)
currawong
I remeber reading an article many years ago, I think it was in The Atlantic, about adults with autism that had grown old with the condition but never been diagnosed. It’s always been there.
Doug R
I WAS THAT KID!!!
WTFGhost
@Tim C: I’m glad you had that reaction; as time marches on, I think our societal awareness improves. In the 90s, I heard so many people saying “they’d have put me on Ritalin if they had it when I was a kid!” (NB: they did. They didn’t use it.)
Well, if you would have been put on Ritalin, then, yes, it makes sense your child would be considered for it, and, come on, guys, make the compassionate connection!”
(“Guys” because it was most often men – girls tend to present ADHD symptoms differently.)
The idea that Ritalin might free a person’s brain didn’t occur to them. And some of them would chain smoke their way through a quart of Dunkin’ coffee, and hear that Ritalin is a stimulant, like caffeine, and nicotine, and…
(That was my howl of agony at missed treatment opportunities, pitched so only dogs and ravens can hear. Also: I did not either scream ‘nevermore,’ so that’s on you. And the raven, of course.)
@Phylllis: Thank you. One of Pratchett’s Discworld books is about an imagined re-building of the post office, and there is, of all things, a pin collector (who becomes the first stamp collector), and you just made me see the person Pratchett loved, when writing that book.
@Wag: If I ever have to work in public again, I’ll need a soundproof, fully shaded, panic room, not because I am panicking, but to prevent the panic of other employees when I let loose with my thoughts on Make America Healthy Again.
(I read mahablog.com, and I just can’t type that acronym, without feeling I’m defiling Barbara O’Brien.)
(BREAKING THE FOURTH WALL) No one has ever called *me* hyperactive! (/BREAKING)
@Ten Bears: While I bemoan missed treatment opportunities, I also mourn treatment failures – it sounds like Ritalin wasn’t right for you, and I hope you wouldn’t think I’m a drug advocate. I can sound that way, because medication is lifesaving for me. The wrong meds (or meds when none are needed) can cause all kinds of harm.
@A woman from anywhere (formerly Mohagan): With my CFS, I identify as “neurodivergent,” and I don’t think I’m on the spectrum… all the time. Maybe sometimes. Maybe a lot, sometimes, and a little all the time (and, to me, that’s just normal). But whatever I be, I’d proudly claim kinship among the nerds who spot the oddball pattern in IT.
(NB: I’m working off a lot of trauma right now, which is probably why I made a lot of replies – it’s something to hyperfocus on for a bit, and when pain stops your ability to process language a couple-three times a second sometimes, that’s a lot of hyperfocus time you can spend! More hyperfocus on anything = less trauma; less trauma means “more easily handled, no matter how low your resources.” coddle yourelf sufficiently, trauma actually can go away, not stick or stain.)
A Ghost to Most
Despite all the cockamamie bullshit about people “catching” autism, autism appears to be a genetic difference between them and normies. For some, it is a devastating existence. For some of us, like my father, son, and I, it’s a superpower with some side effects.
beckya57
Interesting study, hadn’t heard about it. This is in my professional wheelhouse. I think it’s safe to say that lots of people are being diagnosed now with either ADHD and ASD (or both) that weren’t in earlier eras. There’s good reason to think that females with ADHD, for example, have often been missed as children (less disruptive), and having decent verbal skills used to make an ASD diagnosis fairly unlikely. That said, there are people in the field who argue that ASD rates are also increasing. I think we’ll be arguing about this for awhile.
japa21
I have said before, RFK Jr. couldn’t come up with a definition of autism if you held a gun to his head.
3 things have happened over the years, starting in the mid 90’s.
1. Actual diagnostic criteria changed, broadening the scope of what would fall under the autism spectrum.
2. Valid and effective treatment regimens were developed which allowed for a lowering of social stigma.
3. Parents started being more willing to take their children in to see specialists and specialists were more willing to apply the diagnosis.
It took another 10-15 years for this to really have an impact in terms of numbers of people diagnosed with ASD.
So, no, there is no epidemic and no, there is no specific cause yet uncovered.
TheflipPsyd
I truly think it’s good to be doing research on these topics. I don’t believe the prevelemce of these characteristics has changed. And I understand that individuals find it helpful to have a name to describe characteristics of themselves. I would argue though, that all human behavior is on a spectrum and being on the spectrum of a behavior does not lead to diagnosis in every case.
I guess I get itchy when the experience or exhibition of certain characteristics becomes a diagnosis. The DSM states that certain patterns of behaviors qualify as a diagnosis when the characteristics impact psychosocial function. That is, the person is not functioning well in life.
I fear that all this labeling does not widen our understanding of what is neurotypical behavior. I also don’t think it leads to effective treatment for those who are on the upper ends of the spectrum. And, as someone who has been trained on the ADOS and does autism assessments, there is unfortunately a minority of parents who are looking for explanation for behaviors that make them uncomfortable. These parents too often are not interested in helping their children but seem invested in ensuring they are not blamed and/or are avoiding having to change their parenting style to adjust to the child’s needs.
Nukular Biskits
Interesting post.
I’ve always been of the opinion that disorders like autism (disclosure: my youngest g’baby is on the spectrum and, at almost 5, still doesn’t speak and we just now got her to do #1 in the potty … working on #2) have always been around but the reason it seems more prevalent is because of better diagnoses.
I’m not entirely dismissive that environmental factors may play a part in the increase but, until I’ve seen actual verifiable and peer-reviewed evidence of that from real SMEs (not jackasses with brain worms), I’m not interested in going down that path.
Darkrose
Autism when I was growing up in the 70’s and 80’s was “nonverbal white boy rocking and banging his head into walls.” As an extremely verbal little Black girl, I never would have been diagnosed. It’s only now, looking back at my difficulties reading social cues, my lack of filters, and my adult diagnosed ADHD that it’s clear I’m not neurotypical–a word that didn’t come into use until the 1990’s. The idea that there’s a spectrum didn’t seem to be part of the conversation; everything was presented as binary.
That said, the “vaccines cause autism” thing is infuriating because it’s mostly based on a single bad study by a discredited charlatan. If you have a couple hours to spare, I highly recommend watching “Vaccines and Autism: A Measured Response” by hbomberguy, one of the best video essayists on YouTube. He breaks down Andrew Wakefield’s “study” and equally as important, the media response that resulted in dramatic decreases in vaccination. He credits a lot of what he found to journalist Brian Deer, whose persistence finally broke the real story and was instrumental in getting Wakefield’s paper retracted and his medical license revoked.
TONYG
@dnfree: Yeah, I worked in I.T. for forty years and, yup, plenty of people who seem to be “on the spectrum”. (One guy — probably the most intelligent person I ever met — used to have entire conversations with me with his back turned.). (Whether I, too, am “on the spectrum” I’ll let others judge.)
Gretchen
When my godson was diagnosed in the 1980s, I had never heard the word autism and had to ask what that meant. At that time autism was blamed by Bruno Bettelheim on « refrigerator mothers » who were too cold to properly socialize their children.
The contrast between the help she got then and what’s available now is night and day. And, sadly, some parents refuse the help because they don’t want their child to be « labeled ».
Urza
If you’re in tech and don’t exhibit symptoms you’re not actually good at tech. Never seen a normie be able to be amazing at anything in the in the field
Ohio Mom
I always like this explanation of autism as a spectrum, and why having one or two characteristics doesn’t make you autistic — for example, just having sensory processing challenges may qualify you as neurodivergent but not as autistic:
https://neuroclastic.com/its-a-spectrum-doesnt-mean-what-you-think/
The diagnostic boundaries of autism are probably always going to be murky at the juncture where slightly quirky shades into normalcy. There isn’t going to be a sharp line. It’s sort of like, Is your uncle easily irritated, like your aunt insists, or does he have something of a rage disorder, like you suspect? The shades of gray are, well, gray.
Another confounding factor is that people, particularly kids, who have other issues get diagnosed as autistic so that they can get services. Thinking here of an acquaintance’s grandchild who was exposed to many mind-altering substances in utero, and another acquaintance’s niece who has never been the same since her brain surgery. Are either of them actually autistic, I don’t know. I’m glad they are getting needed supports and services but they must be the bane of epidemiologists.
Kayla Rudbek
@Phylllis: also quilting, knitting, crochet, spinning, collecting salt and pepper shakers, etc…heck, humans have been making clothing for about 170,000 years, which involves a lot of repetitive tasks
dnfree
@Urza: I have seen one normal person who is spectacular at tech because she is very driven to get things right, and I’ve seen a number of normal people who are very competent. There are also nerdy people who are not competent.
The correlation I have found striking over the years is between excellent musicians and developing software.
Aggieric
Diagnosed in my 40s and that was me, as a kid. I was lucky in my parents. I had what we now know were meltdowns up through high school, before I learned to better manage them. As a child, they didn’t punish – they just removed me from whatever public space was causing me distress. Often, a busy restaurant or a busy, crowded mall on a weekend. They acknowledged me as their “awkward child” or their “clumsy child” when I fumbled social settings. I still am clumsy – dyspraxia does that. My diagnosis was a real “well that explains a lot” moment for my parents and sibs.
Unknown known
@Ohio Mom: that’s me
I’m ADHD enough that certain kinds of task are unusually difficult (anything that requires sustained attention on something that isn’t interesting enough to hyper focus on, like driving on an a highway for more than 30-60 minutes), but can navigate most of the rest of life ok.
I have some autistic-like social tendencies but not a full range of autistic traits (eg., can usually read people if I’m paying enough attention, few sensory issues, etc)