Wednesday, 17 April 2013

Autism, the autisms or "developmental brain dysfunction"?

"If you've met one person with autism, you've met one person with autism" so the oft-cited phrase goes.

The implication is that whilst unified under the label of presenting with the triad/dyad characteristics of an autism spectrum condition, the heterogeneity present across the spectrum coupled with other comorbidity, allied to factors such as genes, personality, temperament, maturation, environment et al, mean that everyone is different and importantly everyone is dynamic.
Umbrella under an umbrella? @ Wikipedia  

Another term used by some people (including researchers) is that of 'neurotypical'  to somehow denote not-autism. For me however, that's always been a little too simplistic. It implied (a) that there is a definite line between autism and not-autism which kinda over-simplifies things including the broader autism phenotype (BAP), and (b) that there is such as thing as 'neurotypical' and indeed is counter to the phrase: 'if you've met one person, you've met one person' which should surely be as pertinent to not-autism as it is to autism; if you get me?

These concepts are relevant as today I'm talking about two papers: a paper by Whitehouse & Stanley* (open-access) questioning whether autism is one condition or multiple conditions, and a paper by Moreno-De-Luca and colleagues** which implies that we should even be doing away with behaviourally-defined labels such as autism and schizophrenia in favour of an altogether broader definition of 'developmental brain dysfunction' or DBD.

Regular readers might recognise the name Andrew Whitehouse as being one and the same researcher who has talked about various autism-related results from the Raine study (see here and here and here). His latest opinion piece builds on the fact that despite the 70 year anniversary since the first description of autism was published by Kanner (with appropriate consideration for Hans Asperger too), alongside huge amounts of time, money and research efforts, we are really still only scratching the research surface of the condition(s) known as autism. Certainly science hasn't yet come up with many defining 'universal' reasons to account for the appearance of the the clustering of symptoms and as for intervention options, well take a look at the recent draft guidance from NICE to see what I mean. One of the main stumbling blocks he and his colleague opine on is the "phenotypic variability" and how moves should be made towards defining smaller subgroups on the autism spectrum. In effect talking about the autisms over autism as per another very interesting paper by Poot*** (open-access).

To many people this is not new news. That the search for an 'autism gene' or 'autism genetic mutation' (sorry about the cold science term) or indeed 'autism environmental variable' has so far been underwhelming in terms of results coupled to the cost/benefit ratio of such research for example, is testament to the variability present in both autism and not-autism. This demonstrates also how complex a continuum the autism spectrum is. Indeed how complex a thing the human spectrum is****.

Likewise when it comes to intervention, I've talked before on this blog about how we should perhaps be re-assessing the way we look at proposed interventions and in particular focusing on subgroup responses rather than some almighty universal spectrum response to denote intervention success of not. Without equating autism with cancer or vice-versa, the recent opinion paper by Stewart & Kurzrock***** (open-access) might inform this methodological discussion somewhat further.

Whitehouse and Stanley also talk about the lessons learned from cerebral palsy (CP) and how where once CP was thought of as "a unitary disorder", the more contemporary view is somewhat more "umbrella" like. I've covered CP on this blog before so won't say much more about that; I think many people might agree that autism is similarly an umbrella term; even more so when the DSM-V comes into force in literally weeks time (Monday 20th May 2013 apparently).

The Moreno-De-Luca paper goes one stage further. As per the paper and some associated media attention (see here) the suggestion is that not only is there the autisms, but that because of the various overlapping genetic features between the autisms and conditions such as schizophrenia (the schizophrenias), we should be looking at using an even more over-arching concept to group these collected diagnoses together: developmental brain dysfunction (DBD). A sort of umbrella for the umbrella if you like. It's not a new suggestion by the way****** (open-access).

I can imagine that your view of autism - be that a personal perspective of autism, a parental perspective or just an observer looking in - is probably going to influence how you receive this suggestion to some degree. For a researcher looking at the possibility of shared genetics or even epigenetics between conditions which might overlap, there is some sense in looking at the bigger picture. My recent post on common ground (see here) based on the 'five psychiatric disorders linked' paper******* kinda reiterates this position alongside other papers including this one from Caamaño and colleagues******** on subclinical comorbid psychopathology. That and the fact that there might be some convergence when it comes to the autism and schizophrenia spectrums for example (see here) also makes a case. The authors sum it up well: "genes don't respect our diagnostic classification boundaries, but that really isn't surprising given the overlapping symptoms and frequent co-existence of neurodevelopmental disorders".

Other perspectives - and I am only speculating on such viewpoints - might not necessarily share the same sentiments. Aside from leaving out any important relationship that genes might have with little things like the environment, as in maternal immune activation during pregnancy, or all those correlations with other facets of modern living (see here and here), the implication of 'brain dysfunction' takes us back to the whole neurotypical 'us and them' scenario and the questions: what exactly is 'normal' brain function? and what factors can and do affect it? I might add that I can also see how some people might not necessarily be taken with the concept of autism being akin to 'brain dysfunction' in the same way that lumping autism and schizophrenia together might have other, more societal connotations.

I'm going to stop there with this post, save any charges of over-analysing the papers and potential implications. Accepting that a diagnosis is currently the best way for people to [theoretically] receive the help and support they may need, I'm not sure we are in a position to re-write the diagnostic manuals just yet with autism and schizophrenia in mind. That umbrella-ing (is that a word?) autism with other conditions might also impact on the autism awareness message that we've all just had with World Autism Awareness Day is another consideration to bear in mind.

That being said, I do think we have already started to see hints of this brave new world of links and threads coming together. The DSM-V diagnosis of autism seems to be quite explicitly spectral and whilst not yet knowing the consequences of removing diagnoses such as Asperger syndrome and how that Social Communication Disorder category will work, the idea behind the change is sub-type removal similar to that envisaged for schizophrenia (see here and here). I'm not altogether sure but I am also wondering how and whether there will be any exclusion criteria on for example a dual diagnosis of autism and schizophrenia in the new guidance and what effect this might have? We wait and see.

"OK stop already". And I will.

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* Whitehouse AJO. & Stanley FJ. Is autism one or multiple disorders? Med J Aust 2013; 198: 302-303.

** Moreno-De-Luca A. et al. Developmental brain dysfunction: revival and expansion of old concepts based on new genetic evidence. The Lancet Neurology. 2013; 12: 406-414.

*** Poot M. Towards identification of individual etiologies by resolving genomic and biological conundrums in patients with autism spectrum disorders. Molecular Syndromology. February 2013.

**** Mitchell KJ. What is complex about complex disorders? Genome Biology. 2012; 13: 237.

***** Stewart DJ. & Kurzrock R. Fool's gold, lost treasures, and the randomized clinical trial. BMC Cancer 2013; 13: 193.

****** Hrdlicka M. & Dudova I. Controversies in autism: is a broader model of social disorders needed? Child & Adolescent Psychiatry and Mental Health 2013; 7: 9.

******* Cross-Disorder Group of the Psychiatric Genomics Consortium. Identification of risk loci with shared effects on five major psychiatric disorders: a genome-wide analysis The Lancet. February 2013.

******** Caamaño M. et al. Psychopathology in children and adolescents with ASD without mental retardation. JADD March 2013.

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ResearchBlogging.org Whitehouse AJ, & Stanley FJ (2013). Is autism one or multiple disorders? The Medical journal of Australia, 198 (6), 302-3 PMID: 23545020

ResearchBlogging.org Moreno-De-Luca A, Myers SM, Challman TD, Moreno-De-Luca D, Evans DW, & Ledbetter DH (2013). Developmental brain dysfunction: revival and expansion of old concepts based on new genetic evidence. Lancet neurology, 12 (4), 406-14 PMID: 23518333