Autism Series 2013 – Part 3: The Autism “Epidemic”

Weintraub, K., Autism counts. Nature, 2011. 479(7371): 22-4.

Weintraub, K., Autism counts. Nature, 2011. 479(7371): 22-4.

It seems that autism is on the rise.  Once hidden away in institutions or just dismissed as odd, society is now faced with a condition that it is yet to come to grips with.  Some out in the community believe that it must be a toxin, or vaccines or mercury.  Others accuse doctors of simply giving in to the unreasonable demands of pushy parents to defraud the system of money – “Things have reached the point these days where any kid that’s not a charming little extrovert will be accused of being, ‘on the spectrum.’”[1]

So is there an epidemic of kids who are “not charming little extroverts”?  It depends on who you ask.

Take, for example, two articles written in the year 2000.  In the first, titled “The autism epidemic, vaccinations, and mercury”, Rimland said,

“While there are a few Flat-Earthers who insist that there is no real epidemic of autism, only an increased awareness, it is obvious to everyone else that the number of young children with autism spectrum disorders (ASD) has risen, and continues to rise, dramatically.”[2]

The other, written by Professor Tony Attwood, a world authority on Aspergers Syndrome, said,

“… is there an epidemic of people being diagnosed as having Asperger’s Syndrome? At present we cannot answer the question, as we are unsure of the diagnostic criteria, the upper and lower levels of expression and the borders with other conditions. Nevertheless, we are experiencing a huge increase in diagnosis but this may be the backlog of cases that have been waiting so long for an explanation.”[3]

I don’t think it’s very often Prof Attwood is lumped with ‘flat-earthers’.  But you can see the change in perspective from one side looking objectively to the other who need for there to be an “epidemic” of autism in order to strengthen their case.

So who’s right?  To see if this autism “epidemic” hypothesis has any real merit, we need to delve into some numbers.

First, some basic epidemiology – because part of the confusion in looking at the autism numbers is defining exactly what those numbers represent.  Here are some important epidemiology terms from the “Physicians Assistant Exam for Dummies”[4]:

Incidence: For any health-related condition or illness, incidence refers to the number of people who’ve newly acquired this condition.

Prevalence: Prevalence concerns the number of people who have this condition over a defined time interval.

Most autism figures are for prevalence, or often more specifically, point prevalence – “the number of people who have this condition at any given point in time.”

The other thing to remember from my last blog is that initially autism was only diagnosed on the strict rules of Kanner, and was considered to be a single disease caused mainly by bad parenting [5].  So through the 1960’s and 1970’s, only the most severe children were diagnosed as having autism because the high-functioning autism would not have met Kanners criteria, and even if they did, most parents didn’t want the label for fear of the social stigma.

So then, what are the numbers?  The early prevalence was estimated to be less than 5/10,000 or 1 in 2000[6], although in surveys done after 1987, the numbers began to rise past 7/10,000[7].  In the 1990’s, Autism prevalence climbed into the teens and the latest prevalence has been documented for autism is 20.6/10,000[7].

But that’s only about 1 in 485.  The CDC estimated a prevalence of 1 in 88 (113/10,000)[8].  Where did the other 400 people go?

This is where the importance of definitions is highlighted.  Autism is considered part of a spectrum, and at the time of the surveys reviewed by Fombonne, DSM III then DSM IV considered conditions like Pervasive Developmental Disorder and then Aspergers Disorder to be part of that spectrum.  Adding in the rate of PDD and you have a figure of 57.7/10,000 and adding in Aspergers gives you a combined rate of 63.7/10,000, or 1 in 157 people surveyed[7].

And yet even then, who you measure and how you measure makes much more of a difference, because a recent, rigorous study targeting all 7 to 12 year old children in a large South Korean populous found a prevalence of 2.64%, which is 264/10,000 or 1 child in every 38.  The authors noted that, “Two-thirds of ASD cases in the overall sample were in the mainstream school population, undiagnosed and untreated. These findings suggest that rigorous screening and comprehensive population coverage are necessary to produce more accurate ASD prevalence estimates and underscore the need for better detection, assessment, and services.”[9]

So if there has been a fifty-fold change in prevalence (from 5 to 264 cases per 10,000 people) in just thirty years, isn’t that an epidemic?

Well, no.  As much as some might ignorantly deny it, there is no real evidence for it.  Remember the definitions from the “Physicians Assistant Exam for Dummies”[4]:

Incidence: For any health-related condition or illness, incidence refers to the number of people who’ve newly acquired this condition.

Prevalence: Prevalence concerns the number of people who have this condition over a defined time interval.

It’s the rapid rise in the number of new cases diagnosed that defines an epidemic, which is the incidence and not the prevalence[10].  While the prevalence has changed a lot, the incidence has been fairly stable.  From Nature, “Christopher Gillberg, who studies child and adolescent psychiatry at the University of Gothenburg in Sweden, has been finding much the same thing since he first started counting cases of autism in the 1970s. He found a prevalence of autism of 0.7% among seven-year-old Swedish children in 1983 and 1% in 1999. ‘I’ve always felt that this hype about it being an epidemic is better explanation’, he said.”[11]

Fombonne agrees. “As it stands now, the recent upward trend in estimates of prevalence cannot be directly attributed to an increase in the incidence of the disorder.”[7]  He said later in the article that a true increase in the incidence could not be ruled out, but that the current epidemiological data which specifically studied the incidence of autism over time was not strong enough to draw conclusions.

While there’s no epidemic, there is the real issue of the genuinely increasing prevalence.  Why the rise in those numbers?  Fombonne went on to explain, “There is good evidence that changes in diagnostic criteria, diagnostic substitution, changes in the policies for special education, and the increasing availability of services are responsible for the higher prevalence figures.”[7]  Nature published a graph from the work of Professor Peter Bearman, showing that 54% of the rise in the prevalence of autism could be explained by the refining of the diagnosis, greater awareness, an increase in the parental age, and clustering of cases in certain geographic areas.

Weintraub, K., Autism counts. Nature, 2011. 479(7371): 22-4. (Adapted from King, M. and Bearman, P., Diagnostic change and the increased prevalence of autism. International Journal of Epidemiology, 2009. 38(5): 1224-34 AND King, M.D. and Bearman, P.S., Socioeconomic Status and the Increased Prevalence of Autism in California. Am Sociol Rev, 2011. 76(2): 320-46.)

Weintraub, K., Autism counts. Nature, 2011. 479(7371): 22-4. (Adapted from King, M. and Bearman, P., Diagnostic change and the increased prevalence of autism. International Journal of Epidemiology, 2009. 38(5): 1224-34 AND King, M.D. and Bearman, P.S., Socioeconomic Status and the Increased Prevalence of Autism in California. Am Sociol Rev, 2011. 76(2): 320-46.)

From Nature: “The fact that he still cannot explain 46% of the increase in autism doesn’t mean that this ‘extra’ must be caused by new environmental pollutants, Bearman says. He just hasn’t come up with a solid explanation yet. ‘There are lots of things that could be driving that in addition to the things we’ve identified,’ he says.”[11]

There is no autism epidemic, just medical science and our population realising just how common autism is as the definition becomes more refined, people become more aware, and some other biosocial factors come into play.

What can we take from the numbers?  That we’re being overtaken by Sheldon clones?  That soon there will be no more “charming little extroverts”?  If the CDC figure is accurate, then one person in every hundred is on the spectrum, so the world is hardly being overtaken by autism.  But the take home message is that Autism Spectrum Disorders are more common that we ever thought, and there are more people on the spectrum “hiding in plain sight”.  If the study from South Korea is accurate then one person in every thirty-eight is on the spectrum, but two thirds of them are undiagnosed.

Should there be more funding, more resources, or more political representation for people on the spectrum?  Perhaps, although the public and research funds are not unlimited, and other health concerns should also be treated fairly.  But since autism is life long and impacts on so many areas of mental health and education, understanding autism and managing it early could save governments billions of dollars into the future.

Rather, I think that the climbing prevalence of ASD is a clarion call for understanding and tolerance.  If we learn to tolerate differences and practice discretionary inclusion, then both the autistic and the neuro-typical can benefit from the other.  That’s a world which we’d all like to live.

REFERENCES

1. Bolt, A. If the autistic don’t get full cover, where’s the money going? 2013  2013 May 11]; Available from: http://blogs.news.com.au/heraldsun/andrewbolt/index.php/heraldsun/comments/if_the_autistic_dont_get_full_cover_wheres_the_money_going/.

2. Rimland, B., The autism epidemic, vaccinations, and mercury. Journal of Nutritional and Environmental Medicine, 2000. 10(4): 261-6.

3. Attwood, T., The Autism Epidemic: Real or Imagined, in Autism Aspergers Digest2000, Future Horizons Inc: Arlington, TX.

4. Schoenborn, B. and Snyder, R., Physician Assistant Exam For Dummies. 2012: John Wiley & Sons.

5. Pitt, C.E. Autism Series 2013 – Part 2: The History Of Autism. 2013  [cited 2013 2013 Aug 15]; Available from: https://cedwardpitt.com/2013/08/15/autism-series-2013-part-2-the-history-of-autism/.

6. Rice, C.E., et al., Evaluating Changes in the Prevalence of the Autism Spectrum Disorders (ASDs). Public Health Reviews. 34(2).

7. Fombonne, E., Epidemiology of pervasive developmental disorders. Pediatric research, 2009. 65(6): 591-8.

8. Baio, J., Prevalence of Autism Spectrum Disorders: Autism and Developmental Disabilities Monitoring Network, 14 Sites, United States, 2008. Morbidity and Mortality Weekly Report. Surveillance Summaries. Volume 61, Number 3. Centers for Disease Control and Prevention, 2012.

9. Kim, Y.S., et al., Prevalence of autism spectrum disorders in a total population sample. American Journal of Psychiatry, 2011. 168(9): 904-12.

10. “Epidemic vs Pandemic”. 2013  [cited 2013 Sept 03]; Available from: http://www.diffen.com/difference/Epidemic_vs_Pandemic.

11. Weintraub, K., Autism counts. Nature, 2011. 479(7371): 22-4.

 

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Autism Series 2013; Part 1 – Why it matters.

What do you think of when you think about autism?  Is it a TV character like Jake, from Kiefer Sutherland’s recent series ‘Touch’, or perhaps Sheldon from ‘The Big Bang Theory’?  Or is it a movie character like the savant that Dustin Hoffman played in ‘Rain Man’? They are common stereotypes, but they only depict a tiny fraction of the autism that is all around us every day.  Chances are, you would run into people every day who have autism.  Would you be able to pick them?

The current point prevalence rate of autism is given by various international health bodies including the World Health Organization, as one person in a hundred.  With a prevalence of one percent of the population as having autism, you would think it would be better known, better dealt with by teachers, better handled by public officials, better screened and managed by health workers, and better resourced in terms of assistance to families and in terms of research dollars.

But while funding and recognition are important, the greatest impact that the lack of autism awareness has is the human cost.  It is the cost that can’t be measured in terms of dollars, caused by the maligned stigma that having autism brings.

Autism at the less severe end, what used  to be called ‘high functioning’ autism, or what I prefer to classify as (the now unofficial diagnosis of) Aspergers Syndrome, doesn’t make a person look that much different on the outside.  But it makes their behaviour somewhat odd to everyone else.  They have quirks.  They have strange mannerisms.  They have rigid ways of doing things.  They have very narrow interests.  They misread social cues.

“Normal” people don’t like odd.  Especially children.  If you don’t fit in to their particular group-think view of the world, their intolerant tormenting can be merciless and unrelenting.  Some people never grow up though, and many adults with autism can be marginalised by their adult peers. Every barb, joke and isolating experience eroding at the soul of a person with autism until there is nothing left.

This is the most destructive of all. It is death by a thousand insults.

I am writing this series of blogs because I want to help assist in whatever way I can to reduce the ignorance surrounding autism.  There is still so much ignorance out there – simple ignorance because the message is still diffusing through our social networks, and  obstinate ignorance, by people who use pseudoscientific scare mongering to promote their views, or promote bogus treatments for the sole purpose of taking advantage of the desperation of some of those who live with autism.

No matter which form of ignorance is out there, ignorance is ignorance and it does the same damage.  It needs to be stopped.

When I was a little boy, I was odd.  It took me a while before I started talking.  I had an obsession with vacuum cleaners and watches.  I was the misfit, or the loner.  I was incessantly bullied in the latter half of primary school and almost all the way through high school.  I didn’t want to go out and be with large groups of other kids.  My parents made me go to marshall arts training, cub scouts, church groups and school holiday excursions.

I hated those social outings.  I had huge anxiety being in these large groups.  Even when I wasn’t being mocked or belittled, I still felt anxious because I didn’t naturally fit in with the other kids.  The leaders of the group would go out of their way to include me but that had the opposite effect of highlighting how much of a social misfit I was.  The anxiety was disabling when I was in middle high school.

Thankfully I was smart, mainly in maths and science.  Academic achievement was my only positive, so I took refuge in studying.  I graduated in the top percentile in my state, and made it into medical school.  I did a whole medical degree, five years in hospitals including several in subspecialty paediatrics, and a fellowship in General Practice, and another eight years of GP experience, before my son was diagnosed as being on the autistic spectrum.

Despite years of medical training, It’s only been since my son’s diagnosis that I have been realising just how much of my quirky behaviour and social dysfunction was due to the fact that I’m on the spectrum too.  All those years, I thought I was retarded, socially incompetent, a freak.  All those years, I was bullied, harassed and made to think I was stupid, just because I didn’t naturally understand the unspoken social codes , but no one explained them to me.

That’s nearly forty years of living with self-doubt, low self-esteem, low self-confidence, and various mental health issues, because I never knew, because no one else knew, because of ignorance and intolerance.

So it stings when I hear people spread mistruths about ASD, and it pains me when the mistruths are spread by people who should know better.  It makes me mad when the mistruths come from self-titled ‘experts’.

I don’t want my son going through the same stigma and denigration, or anyone else on the spectrum for that matter.  The truth about autism – what it is, what it is caused by, and what strengths autism bestows, need to hold sway so that death by a thousand insults is no longer tolerable in our progressive society.

I will publish further blog posts over the coming days to weeks on what autism is, on why it seems to be increasing, and the latest scientific evidence on what autism may be caused by.  I will devote a whole blog (or two) to the misinformation surrounding vaccines and autism.  So stay tuned.