Autism: a spectrum, dimensions or clusters? How about a multi-dimensional cluster of spectrums?

A write-up (see here) of the paper by Hyunsik Kim and colleagues [1] was the initial impetus for formulating this blog post, but it quickly escalated into something a little larger when the findings from Frank Duffy & Heidelise Als [2] also popped up.

The question at hand: how should one conceptualise autism? Is it truly a spectrum as per the Lorna Wing proposition, or is it something a trifle more complicated? As per the title of this post, should we perhaps be thinking about autism as some sort of "multi-dimensional cluster of spectrums?" I'll come back to that idea shortly.

Well, it's not for me to make definitive conclusions on this blog. Science rarely, if at all, provides an absolute 'truth' but rather the probability that something is approaching truth. Such a notion goes double when you consider the singular label of autism and the huge heterogeneity that it encompasses. There are no easy answers and probably little or no truths.

Starting with the Kim paper (including some notable names such as the surname 'Gadow') and the name of the research game was modelling, modelling in a computational sense. So: "The sample comprised 3,825 youth, who were consecutive referrals to a university developmental disabilities or child psychiatric outpatient clinic." The CASI-4R - formulated by Prof. Gadow - was the schedule administered, which includes "an ASD [autism spectrum disorder] symptom rating scale" among other things. Some nifty statistics were applied to the data and the initial findings were 'tested' on a further group of over 2500 children.

Results: "Based on comparison of 44 different models, results indicated that the ASD symptom phenotype is best conceptualized as multi-dimensional versus a categorical or categorical-dimensional hybrid construct." And the dimensions mentioned in that 'multi-dimensional' statement? Well, lucky for us they were something familiar: "social interaction, communication, and repetitive behaving."

Then to the Duffy/Als paper (again, these authors are no stranger to autism research) and a similar starting point: "The authors postulate that the broad definition of an omnibus 'spectrum disorder' may inhibit delineation of meaningful clinical correlations." Indeed, very familiar (see here). The conclusion: "evidence that an objectively defined, EEG [electroencephalogram] based brain measure may be helpful in illuminating the autism spectrum versus subgroups (clusters) question." The tool used by Duffy/Als in their study was something called NbClust "specifically designed to provide an objective means, i.e. independent of investigator choice, to identify the ‘optimal’ cluster number within a population." Said tool was applied to EEG data derived from 400 participants diagnosed with an ASD. Statistics and more statistics applied to the data revealed that: "430 subjects diagnosed as being on the autism “spectrum” and represented by 40 EEG coherence factors..., fell into two distinct clusters." These autism spectrum clusters differed from each other and importantly, from "554 subject neuro-typical control group subjects, not involved in the clustering process." Interesting results but an unfortunate use of the term 'neurotypical' (see here). Duffy & Als conclude that their data support a view whereby "autism disorder should not be seen as a continuous spectrum." So Kim & Duffy/Als arrive at similar conclusions: a singular 'spectrum' idea of autism is probably not the best way of conceptualising the essence of the label.

I would perhaps add in a little more evidence for the idea that 'multi-dimensional clusters of spectrums' is a potentially better fit. I used the words 'spectrums' (plural) because there is a growing body of evidence to support the idea of more than one 'type' of autism. I say that from the perspective of evidence for autism being 'acquired' under several different circumstances (e.g. accompanying inborn errors of metabolism, linked to exposure to certain infections or diseases, etc). There's also evidence that clinical profiles under the umbrella term autism are not uniform (e.g. regressive autism, the so-called 'optimal outcomers', differing developmental trajectories, etc). And when one looks at something like the success (or not) of intervention, it's plain to see that there is no universally shared genetics and/or biology of autism in the singular either (see here and see here for examples). Add in the idea that autism rarely appears in a diagnostic vacuum (see here) and that said comorbidity might 'cluster' in some subgroups of autism (see here), and I hope you can see why 'plural' might be a good addition to any attempt to re-conceptualise autism: spectrum, dimension, tapestry, cluster or however you think it should be defined...

Oh, and since we're on the topic of trying to conceptualise autism, a new book out recently has been reviewed in Nature (see here). It talks about how "conclusive findings about sex-linked brain differences have failed to materialize" which is particularly apt in relation to previous talk about 'extreme male brains' as a way of conceptualising [some] autism (see here). One quote I particularly liked from the review is this one: "The brain is no more gendered than the liver or kidneys or heart."

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[1] Kim H. et al. Quantifying the Optimal Structure of the Autism Phenotype: A Comprehensive Comparison of Dimensional, Categorical, and Hybrid Models. J Am Acad Child Adolesc Psychiatry. 2018 Oct 29. pii: S0890-8567(18)31894-X.

[2] Duffy FH. & Als H. Autism, spectrum or clusters? An EEG coherence study. BMC Neurol. 2019 Feb 14;19(1):27.

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On autism symptom trajectories and diagnosing autism late...

It's another one of my mash-up posts today, as two paper are brought to the blogging table. The first paper is from So Hyun Kim and colleagues [1] and looked at the rather interesting topic of differing symptom trajectories in the context of diagnosing autism. The second paper by Sally Ozonoff and colleagues [2] follows in a similar vein in terms of their analysis of children "who had undergone multiple comprehensive assessments in preschool and were determined to be ASD [autism spectrum disorder]-negative, only to meet criteria for ASD when tested in middle childhood."

Both these paper originate from well-respected autism research groups and appear in the same respected journal (Journal of the American Academy of Child & Adolescent Psychiatry). The common theme between them is that within the significant heterogeneity seen under the label of 'autism', there are various different developmental and presented symptoms trajectories, some of which (a) are not as stable as one might imagine, and (b) do not seemingly follow the oft-used assertion that 'autism is present and manifests from birth'. Indeed, on that last point, the implications are that autism is sometimes very much associated with regression (see here) and onward, that genetic and/or non-genetic post-natal factors may very well influence some children reaching clinical cut-off thresholds for a diagnosis of autism (see here for example).

So, to the Kim paper first: authors looked at over 900 "observations of the Autism Diagnostic Observation Schedule (ADOS)" from nearly 150 young children. They were specifically looking at symptoms trajectories based on those ADOS scores and whether or not 'clusters' of similar symptom trajectories were evident. The answer: yes, yes there were some different clusters of symptom trajectories noted. Not six developmental trajectories as per other research (see here) but four clusters: "Nonspectrum ∼25%; Worsening ∼27%; Moderately-Improving ∼25%; Severe-Persistent ∼23%)." Authors also report how: "Trajectory clusters varied significantly in the proportions of confirmatory ASD diagnosis, the level of baseline and final verbal/nonverbal abilities, and symptom severity."

Then to the Ozonoff paper: "Fourteen children met inclusion criteria for the Late Diagnosed group and were compared to a large sample of high- and low-risk siblings from the same sites who had ASD or typical development (TD) outcomes at age 3." Authors focused in on these 14 children and concluded that: "Seven showed very little evidence of ASD in preschool, while seven demonstrated subtle, subthreshold symptomatology." They also suggest that their results identifying a small but important group of children who seemingly first present with 'typical' behaviour but then 'grow into' the presentation of autism "shed light on reasons why the mean age of ASD diagnosis remains over 4 years." Indeed (see here).

I don't really need to say much more than I have already on these studies. Aside that is, from reiterating that the autism spectrum is truly wide and heterogeneous in both symptom presentation and also it seems, with regards to symptom onset and stability too. Alongside other research (see here) talking about how the presentation of autistic signs and symptoms wax and wane for some, I'm wondering when autism research is going to start looking beyond just presented behaviour, at whether for example, genetic and biological 'changes' might accompany such fluidity in behaviour and 'cluster' differences. Y'know, the same way that another group seemingly heading in the opposite direction - those who 'lose their diagnosis' (see here and see here) - also need to be closely investigated from a biological point of view too. It's only when we have such biological data that we can then start meaningfully probing the possible hows-and-whys...

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[1] Kim SH. et al. Variability in Autism Symptom Trajectories Using Repeated Observations from 14 to 36 Months of Age. Journal of the American Academy of Child & Adolescent Psychiatry. 2018. Sept 5.

[2] Ozonoff S. et al. Diagnosis of Autism Spectrum Disorder After Age 5 in Children Evaluated Longitudinally Since Infancy. Journal of the American Academy of Child & Adolescent Psychiatry. 2018. Sept 3.

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Yet more evidence suggesting that 'lifelong' is not an accurate description of some autism

The findings reported by Amaria Baghdadli and colleagues [1] didn't really come as a great surprise to me. In their study designed to "investigate the adaptive trajectories and their risk factors in ASD [autism spectrum disorder]", researchers reported that just over 5% of their cohort initially categorised as having autism "fell under the ADOS [Autism Diagnostic Observation Schedule] threshold" at a later point in time. 'Fell under the ADOS threshold' translates as not meeting the criteria for autism on one of the gold-standard assessment instruments (that's assessment, not screening) and by inference, not being autistic. Important too was another statistic from their study: "11.9% converted to atypical autism" and: "Most atypical autism diagnoses were unstable."

The Baghdadli study was quite an extensive one. We are told that participants were "prospectively followed" from childhood to adulthood with assessments (including the Vineland Adaptive Behaviour Scales) covering a period of 15 years. Outside of some participants seemingly exiting the diagnosis of autism, authors also talked about different trajectories noted among their cohort that ties in with lots of other research on this topic (see here and see here). The authors concluded that: "changes in diagnostic, speech, and adaptive status are not uncommon, even for individuals with low measured intelligence or apparent intellectual disability, and are sometimes difficult to predict." It's interesting too that: "One-third of children who are nonverbal at 5 years are verbal within 15 years, mostly before 8 years of age."

Minus any sweeping generalisations, I appreciate that talk about the 'instability' of presented symptoms/traits/characteristics and autism is not well received in some quarters. Despite study after study after study being published in the peer-reviewed science domain suggesting that, for some, autism is not a lifelong condition by diagnostic standards, there is a reluctance for some people to accept such data. I've heard for example, people talking about such a reversal of symptoms in the context that 'they weren't autistic in the first place' as if such commentators have some special insight into often complete strangers that surpasses professionals with years of clinical experience. I also don't doubt that talk about masking and camouflaging of symptoms, whilst legitimate in the context of [some] autism (albeit with a lot more science needed), might also eventually be used as another explanation too if it hasn't already. But please, don't tell me that preschoolers are also masking during their various assessments (see here)...

The fact remains that the peer-reviewed science on this topic is pretty unanimous insofar as autism not being 'lifelong' for everyone (see here). And yet again we need further investigations on this topic to elucidate whether a change in overt symptom profile heading towards asymptomatic also means changes in biological parameters or genetic functions/expression. Whether one day it might even be possible to predict who will fit into such a categorisation. I'm also keen to see further work being carried out around the idea that losing a diagnosis might have some pretty important effects on other quality of life affecting labels/symptoms/states (see here) that seem to be over-represented in relation to autism (see here). And then a final question: what role does intervention potentially play in such unstable behavioural profiles (see here) and I'm not just talking about 'behavioural' intervention either?

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[1] Baghdadli A. et al. Adaptive trajectories and early risk factors in the autism spectrum: A 15‐year prospective study. Autism Research. 2018. Oct 1.

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Yet more "lost their diagnosis" and autism research. Not for all but...

The question posed in the title of the paper by Solomon and colleagues [1] - "What will my child's future hold?" - examining the "phenotypes of autism spectrum disorder (ASD) based on trajectories of intellectual development from early (ages 2-3 ½) to middle (ages 5-8) childhood" - is an interesting one and a question that many parents/caregivers will probably ask or have asked at one point or another.

It's also an important question because throughout all the sweeping statements that have been made about the autism spectrum past and present, the generalisation that ALL autism is 'lifelong' is one of the more popular ones despite [peer-reviewed scientific] evidence pointing to the contrary (see here for example).

By saying all that I'm not trying to minimise the effect(s) that autism has on the lives of many, many people day-in and day-out throughout their lives and the varying requirements for suitable support. Just that, as per the notion 'if you've met one autistic person, you've met one person with autism' (or words to that effect), the experience(s) of continually hitting the diagnostic thresholds across the lifespan is likely to be different for different people as a function of many, many different factors. I say this acknowledging for example, the rise of 'compensation' in the context of autism recently (see here).

Solomon et al drew on data derived from the Autism Phenome Project including over 100 children "initially diagnosed with ASD." Researchers were particularly interested in cognitive trajectories as measured by IQ between 2 and 8 years of age and whether autistic and other related symptoms/traits were also affected by any changes to intellectual functioning. As it happens, they might be...

"A four class model best represented the data" meaning that participants typically fell into one of four 'patterns' with regards to their intellectual functions/trajectories. This included: "High Challenges (25.5%), Stable Low (17.6%), Changers (35.3%), and Lesser Challenges (21.6%) groups." As per the title of this post, I'm particularly interested in those described as 'Changers' or 'Lesser Challenges' who "demonstrated the most significant IQ change that was accompanied by adaptive communication improvement and declining externalizing symptoms" and "showed a significant reduction in ASD symptom severity" respectively. Indeed, within the Lesser Challenges group we are told that "by age 8, 14% of them no longer met ADOS-2 criteria for ASD." In other words, they did not reach cutoffs for the diagnostic criteria for an autism spectrum disorder (ASD) using a gold-standard assessment instrument and so could be considered not autistic by diagnostic standards.

Also important to the Solomon findings was the observation that: "Intervention history was not associated with group status." I'm not going to say too much more about this at the present time, but if replicated, the implications are pretty huge particularly where the current drive towards early intervention in autism is leading us (see here).

Although not always welcomed by everyone, the idea that a diagnosis of autism is permanent and immutable for all does not stand up well to scientific scrutiny. The best guess estimates currently suggest that somewhere between 9 and 12% of children/adults will 'lose their diagnosis' (see here and see here); also potentially affecting the presence of some important over-represented comorbidity too (see here). The old 'they weren't autistic in the first place' argument is a typical response from some nay-sayers on this topic; something which unfortunately contributes to the denigration of some important parts of the autism spectrum. Certainly a part of the autism spectrum that we can learn a lot from as the Solomon results are starting to show.

Indeed, given the other 'biological' focuses of the Autism Phenone Project [2] I'm hoping that we'll eventually see further results from this initiative providing important information on possible biological correlates linked to those who "no longer met ADOS-2 criteria for ASD". If ever there was a research study needed on autism, it is one including a little more biological and genetic information about those who move from autism to not-autism and what it could mean for the wider autism spectrum and particularly the concept of 'the plural autisms'...

To close, 'I want a deep fried turkey'....

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[1] Solomon M. et al. What will my child's future hold? phenotypes of intellectual development in 2-8-year-olds with autism spectrum disorder. Autism Res. 2017 Oct 27.

[2] Onore CE. et al. Levels of soluble platelet endothelial cell adhesion molecule-1 and P-selectin are decreased in children with autism spectrum disorder. Biol Psychiatry. 2012 Dec 15;72(12):1020-5.

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Multiple 'depressions' and multiple trajectories? Sounds very familiar.

I'm a fan of the idea that the categorical labelling system currently used in psychiatric and psychological circles probably isn't fit for purpose these days. Y'know, the idea that compartmentalising people into diagnostic boxes with an overarching title whilst useful for general identity and statistical classification, does little to inform about individual experiences or the important cross-over in presentation between and across different labels. Don't even get me started on how the use of such all-encompassing labels have probably hindered as much as helped research on these important presentations.

The continued moves towards 'pluralisation' with autism (see here) or schizophrenia (see here) in mind reflect the strength of feeling in this area and how reform might be needed. This is probably also why RDoC has continued its rise (and rise).

The paper by Katherine Musliner and colleagues [1] continues the idea that heterogeneity in the presentation of psychiatric or behavioural conditions might be good evidence for plural conditions, this time with depression in mind. With the aim to "characterize patterns and correlates of 10-year course trajectories of MDD [major depressive disorder]" researchers relied on data from one of those oh-so-useful Scandinavian registries - "The Danish Psychiatric Central Research Register (DPCRR)." With participant numbers in the thousand (~11,000) diagnosed with MDD, researchers followed participant records for 10 years after their initial MDD diagnosis. They looked at various variables including "past-year inpatient, outpatient, or emergency contact at a psychiatric hospital" as a primary 'response variable' and other details around "previous record of suicide attempt or self-harm, severity of the initial MDD diagnosis (mild, moderate, severe without psychotic features, severe with psychotic features, and severity unspecified), and parental records of psychiatric diagnoses in the DPCRR (unipolar depression, bipolar disorder, schizophrenia and related disorders, substance abuse, and anxiety or somatoform disorders)." Further reading about the study aims and findings can be found in an accompanying editorial [2].

Results: bearing in mind that researchers excluded individuals with other diagnoses such as bipolar disorder or schizophrenia from the analysis, four primary classes of trajectory were noted based on that primary response variable dealing with contact with psychiatric services: "brief contact (77.0%), prolonged initial contact (12.8%), later reentry (7.1%), and persistent contact (3.1%)." It is perhaps pleasing to see that for the majority of people diagnosed with MDD, their experiences of the condition were either ones of recovery or movement to care from other healthcare providers outside of specific psychiatric services as a consequence of their membership of the grouping 'brief contact'. Although including a much smaller percentage of people, the trajectory described by the grouping 'persistent contact' potentially reflects a type of MDD that is perhaps less treatment responsive and more chronic in terms of its presentation. The authors also suggest that this finding "suggests that a large proportion of specialized MDD treatment goes to a small proportion of cases."

Insofar as the other variables potentially linked to the classes of trajectory, a few notable observations emerged from the data. So: "severity of the first diagnosis was most strongly associated with trajectory class membership: the more severe the first diagnosis, the higher the probability of a more severe 10-year trajectory." Sex/gender was also a potential correlate in that: "Female sex was most strongly associated with membership in trajectories characterized by prolonged contact."

Familial psychiatric history also revealed some potentially interesting correlates such that: "different psychiatric diagnoses in parents were associated with different MDD trajectory patterns in offspring."  Picking out one or two details, researchers observed that those participants with a parental history of depression were for example, more likely to belong to the 'later re-entry' group. A family history of a primary psychotic disorder often led to categorisation in the 'persistent contact' grouping and onwards a more chronic disease course with a greater likelihood of poor treatment response.

Cumulatively, these findings provide good evidence that trajectory in MDD is diverse and potentially associated with various different factors including sex and parental experiences of mental illness. Further the authors note: "Different psychiatric disorders in parents are associated with different MDD trajectory patterns in their offspring, which suggests that observable heterogeneity in the course of MDD may reflect differences in the genetic underpinnings of the disorder." I'd be minded to suggest that science should continue to be wide-ranging in light of the 'heritability' aspect indicated (including the idea that structural genomics might not be the be-all-and-end-all of any relationship) but the Musliner findings do perhaps add to the increasingly louder calls for an overhaul of the way we categorise mental health. Oh, and the idea that psychiatric/behavioural diagnoses can be 'remitting' at a clinical descriptive level is something else we should be willing to take on board more generally, even if it does mean challenging dogma (see here).

Now, if one assumes that there may be various 'types' of depression, how about entertaining the idea that treatment-wise we might need to look to wider bodily functions such as that related to the immune system at least for some people? It has been mentioned before y'know...

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[1] Musliner KL. et al. Heterogeneity in 10-Year Course Trajectories of Moderate to Severe Major Depressive Disorder. JAMA Psychiatry. 2016. March 2.

[2] Shelton RC. The Course of Illness After Initial Diagnosis of Major Depression. JAMA Psychiatry. 2016. March 2.

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Musliner, K., Munk-Olsen, T., Laursen, T., Eaton, W., Zandi, P., & Mortensen, P. (2016). Heterogeneity in 10-Year Course Trajectories of Moderate to Severe Major Depressive Disorder JAMA Psychiatry DOI: 10.1001/jamapsychiatry.2015.3365

9% of those diagnosed with autism might have optimal outcome?

"Although for many children, Autism Spectrum Disorder (ASD) is a lifelong disability, a subset of children with ASD lose their diagnosis and show typical cognitive and adaptive abilities."

Unfortunately, that sentence taken from the report by Emily Moulton and colleagues [1] including one Deborah Fein on the authorship list, is not likely to be taken well by some people. Indeed, the whole concept of 'optimal outcome' with autism in mind (see here) has sometimes been met with outright hostility despite this being peer-reviewed science that, on occasion, has been independently verified (see here and see here). I can't say for sure why optimal outcome (OO) has not been received in the manner it should have been but I'd guess that dogma might have something to do with it (yet again). That some commentators have also made throw away comments to the effect that 'they were never autistic in the first place' I think, does a real disservice to an important group of people who were, very definitely, at some time on the autism spectrum. Heterogeneity people, heterogeneity.

No mind. The findings reported by Moulton et al add to a considerable bank of data suggesting that those with OO might be an important research focus for autism. This time around some 200 children "with an ASD at age two who were reevaluated at age four" are discussed and how most (~80%) retained their ASD label between the two testing occasions. But, and it is an important point: "9 % showed "optimal progress": clear ASD at age two but not at age four, and average cognition, language, communication and social skills at age four." The Masters thesis of Moulton can be read here containing more details.

Although requiring much more study, the idea that nearly one in ten children on the autism spectrum might 'lose' their diagnosis sounds quite important to me. Further: "Early child-level factors predicted optimal progress: diagnosis of PDD-NOS [Pervasive Developmental Disorder - Not Otherwise Specified], fewer repetitive behaviors, less severe symptomatology and stronger adaptive skills." A roadmap for where early screening and importantly, intervention might want to focus perhaps? Bear in mind that there may be other factors too [2].

There remains still quite a bit to do in this area before textbooks are re-written and the like. Personally, I'd also like to see a little bit more information about medical history included in future write-up and whether variables such as onset of symptoms might play some role in OO. Y'know, when something like infection has/had been 'correlated' with symptoms onset (see here for example) or autism in the presence of ear infections (see here) to name a few potentially important variables. I'm also yet to see whether genomic analysis has been suitably applied to the OO group too, taking into consideration the importance of gene expression as well as the focus on structural genetics. I'd also be interested to see what happens as and when DSM-5 criteria are more consistently used with this group, particularly in terms of the social communication disorder (SCD) label (see here) and how many might 'move' rather than 'lose' a diagnosis.

I do also have to caution that OO does not mean that early developmental issues manifesting as autism or autistic traits might not still exert an influence on a person. The paper by Inge-Marie Eigsti and colleagues [3] confirms as much, bearing in mind that brain imaging is still in its infancy with autism in mind and the wide heterogeneity (and comorbidity) present in the spectrum that complicates matters.

Lots more to see and do methinks, including further analysis on just how important the figure '9%' might be to optimal outcome and autism [4] (or at least when it comes to the question of diagnostic stability). All that, set within the context of paying a little more respect to the experiences of an important group who were at one time, part and parcel of the very wide autism spectrum.

And while I have you, I'd like to draw your attention to a new report from the folks over at Treating Autism in conjunction with Queen Mary University of London suggesting that 'could do better' is the mark awarded for access to good quality health support for those on the autism spectrum here in Blighty.

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[1] Moulton E. et al. Early Characteristics of Children with ASD Who Demonstrate Optimal Progress Between Age Two and Four. J Autism Dev Disord. 2016 Feb 19.

[2] Artigas-Pallares J. & Paula-Perez I. Autisms that 'cure themselves'. Rev Neurol. 2016 Feb 21;62(s01):S41-S47.

[3] Eigsti IM. et al. Language comprehension and brain function in individuals with an optimal outcome from autism. Neuroimage Clin. 2015 Dec 2;10:182-91.

[4] Wu YT. et al. Retention of autism spectrum disorder diagnosis: The role of co-occurring conditions in males and females. Research in Autism Spectrum Disorders. 2016; 25: 76-86.

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Moulton E, Barton M, Robins DL, Abrams DN, & Fein D (2016). Early Characteristics of Children with ASD Who Demonstrate Optimal Progress Between Age Two and Four. Journal of autism and developmental disorders PMID: 26895327

Early sex differences are not autism-specific

The title of this post mirrors the title of the paper published by Daniel Messinger and colleagues [1] (open-access available here) that reported on "younger sibling sex differences and proband sex differences on the odds of ASD [autism spectrum disorder] in a large sample of prospectively followed high-risk siblings."

Researchers found that alongside "a three-to-one male:female odds ratio in ASD recurrence... the emergence of ASD symptoms in high-risk siblings—both with and without eventual ASD outcomes—occurs in the context of naturally occurring sex-related variability." Further that their results cast "doubt on a female protective effect among high-risk ASD siblings."

Based on participant data derived from the Baby Siblings Research Consortium (BSRC) [2], a collaborative initiative focused on identifying the earliest signs and symptoms of autism, researchers assessed cognitive functioning and autism symptom severity in over 1800 infants, over 1200 of whom were categorised as 'high risk' insofar as being a "younger sibling of a proband with an ASD diagnosis." Of those 1241 high-risk siblings "252 had ASD outcomes" on the basis of a clinical best estimate diagnosis derived from the various data sources available for each participant.

Results: well, there were quite a few of them as previously discussed but I'm going to pick out a few highlights:

• "The male rate of ASD recurrence in the high-risk siblings was approximately 1 in 4 (26.7 %) while the female rate was 1 in 10 (10.3 %)." Further: "The overall—combined male and female—ASD recurrence rate of 19.5 % yielded an ASD outcome for approximately one in five high-risk siblings." This is an important addition to the previous research done on sibling recurrence rates (see here) bearing in mind the potential effect of variables such as reproductive stoppage and multiplex status.
• "Challenging accounts of greater female affectedness, there was no evidence that girls exhibited lower levels of cognitive functioning or higher levels of symptom severity than boys." The idea that there may be a female phenotype of autism has gained significant research traction in recent times (see here) partially based on the idea that it may take 'more genetic issues to trigger autism in girls than boys'. Alongside the idea that females may somehow possess greater protection against autism is the suggestion that autism when it does appear in females, may show differences in terms of severity perhaps as a function of that larger genetic load required. Messinger et al however, report that things might not be so simple.
• "Boys across all groups exhibited slower growth trajectories and lower levels of cognitive performance than girls in fine motor, visual reception, receptive and expressive language functioning." Harking back to some previous musings on the 'fragile male' (see here) Messinger et al showed small but notable difference across the sexes and across ages suggesting female superiority of somewhere between "1.06 to 3.3 months on age-equivalent scores" compared to males. That's not to say males did not develop - everyone developed - rather that girls seemed to develop skills at a faster rate.
• "With respect to the ASD symptom severity indices, males exhibited higher levels of repetitive behaviors than females, but there were no sex differences in social affect severity scores." This finding tallies with other research in this area (see here). The indication being that aspects such as stereotyped language, hand and finger mannerisms or complex mannerisms may be quite a bit more prevalent in 'boy autism' compared to 'girl autism'. More than that however, such repetitive behaviours might be more present in boys over girls (taking out the variable of autism diagnosis) "consistent with a male focus on regularity in the behavior of non-social objects and events." 'Boys and their toys' is a phrase that springs to mind.

The authors conclude that their results "suggest that male:female ASD differences are not ASD-specific but instead reflect more general sex differences reflected through a prism of autism-linked symptoms."

These are interesting results that gain some scientific traction as a function of the large participant numbers included for study and the prospective nature of the study initiative. The authors have made quite a bit of the fact that their results provide "no overall evidence of a female protective effect" in their high-risk siblings group but acknowledge the need for further investigations in this area specifically where female autism is present and how "female probands in multiplex families (two or more female siblings) [may] confer greater risk for ASD in successive offspring." I wonder if this might include some further thought on how sex differences in brain plasticity [3] might potentially be linked to autism?

Once again, autism reveals just how complicated a condition it is...

Music: The Slits - Typical Girls.

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[1] Messinger DS. et al. Early sex differences are not autism-specific: A Baby Siblings Research Consortium (BSRC) study. Mol Autism. 2015 Jun 4;6:32.

[2] Messinger D. et al. Beyond autism: a baby siblings research consortium study of high-risk children at three years of age. J Am Acad Child Adolesc Psychiatry. 2013 Mar;52(3):300-308.

[3] Mottron L. et al. Sex differences in brain plasticity: a new hypothesis for sex ratio bias in autism. Molecular Autism. 2015. 6; 33.

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Messinger DS, Young GS, Webb SJ, Ozonoff S, Bryson SE, Carter A, Carver L, Charman T, Chawarska K, Curtin S, Dobkins K, Hertz-Picciotto I, Hutman T, Iverson JM, Landa R, Nelson CA, Stone WL, Tager-Flusberg H, & Zwaigenbaum L (2015). Early sex differences are not autism-specific: A Baby Siblings Research Consortium (BSRC) study. Molecular autism, 6 PMID: 26045943

Responding to parental concerns about possible offspring autism

"In conclusion, despite early parental concerns, children with ASD [autism spectrum disorder] receive less proactive provider responses to these concerns than children with ID/DD [intellectual disability/developmental delay]. Less proactive/more passive provider responses are associated with delays in diagnosing ASD."

So said the paper from Katharine Zuckerman and colleagues [1] (open-access) who using "nationally representative data from the 2011 Survey of Pathways to Diagnosis and Treatment" tried to answer the following questions: "(1) Did child age at first parental concern and first parental conversation with provider differ among children eventually diagnosed with ASD compared with those diagnosed with DD or ID?; (2) Did provider response to concerns differ among these conditions?; and (3) Among children with ASD, was a more proactive/less reassuring provider response to parental concerns associated with earlier ASD diagnosis?"

What they found has been reported by various media (see here for example) and indicated that when it comes to early parental concerns about the behaviour and development of their offspring: "compared with parents of children with ID/DD, parents of children with ASD reported concerns earlier and had earlier provider conversations about these concerns, but were more likely than to receive reassuring/passive provider responses to those concerns." Indeed, the authors implied that healthcare provider behaviour might be an important factor in 'delayed autism identification'.

As it is in many areas of autism research, we've been here before. In a previous post titled ''You know what boys are like' and the autism pre-diagnostic experience' (see here) I discussed the paper by Sara Ryan & Helen Salisbury [2] (open-access). How for example, the UK experience of autism diagnosis might not be so different from the US experiences talked about by Zuckerman et al specifically with the idea that for some parents, premature reassurance by health professionals about their concerns about their child's behaviour/development may not sit too well with parents and may result in delays in assessment/diagnosis for the child. By saying this, I'm not trying to tarnish medical reputations. Children do not uniformly develop in the same way with lots of stopping and starting in skills learned in the early years which does not necessarily mean 'autism' or any other label. But Zuckerman et al are right to highlight this issue.

From the collected peer-reviewed evidence currently available, we know that there are many variables potentially affecting age of diagnosis when it comes to autism (see here). We also know that autism assessment/diagnosis is one part science and one part of art in terms of the skills of those charged with such tasks and the path does not always run as smoothly as we would wish (see here). Late, delayed or mis-diagnosis however, can be a source of significant stress to both families and children/adults alike (see here) particularly when parental views and opinions have been shown to be pretty accurate when it comes to the appearance of something like autism (see here). I might also direct you to the paper by Sacrey and colleagues at this point [3].

The best way forward? Accepting that resources are being stretched for many different reasons and that assessments cost both in terms of finance and human resources, perhaps give parents/significant others the benefit of the doubt when they say they think there might be 'issues' for someone. Dedicate greater resources towards how screening and assessment could be done more cost-effectively and reliably in the digital age (remember that YouTube work?) and focus on how early diagnosis might offer so much to a person (see here). Oh, and consider that "screening for ASD may need to be repeated multiple times in the first years of life" [4].

As is customary on this day: May the 4th be with you...

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[1] Zuckerman KE. et al. Parental Concerns, Provider Response, and Timeliness of Autism Spectrum Disorder Diagnosis. The Journal of Pediatrics. 2015. 14 April.

[2] Ryan S. & Salisbury H. 'You know what boys are like': pre-diagnosis experiences of parents of children with autism spectrum conditions. Br J Gen Pract. 2012 May;62(598):e378-83.

[3] Sacrey L-A R. et al. Can Parents’ Concerns Predict Autism Spectrum Disorder? A Prospective Study of High-Risk Siblings From 6 to 36 Months of Age. JAACAP. 2015. March 27.

[4] Ozonoff S. et al. Diagnostic stability in young children at risk for autism spectrum disorder: a baby siblings research consortium study. J Child Psychol Psychiatry. 2015 Apr 29.

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Katharine Elizabeth Zuckerman, Olivia Jasmine Lindly, & Brianna Kathleen Sinche (2015). Parental Concerns, Provider Response, and Timeliness of Autism Spectrum Disorder Diagnosis The Journal of Pediatrics : 10.1016/j.jpeds.2015.03.007

What have we learned about autism?

Today's post is a bit of mash-up based on the review paper by Jason Chen and colleagues [1] and a news entry from Autism Speaks titled: '10 Years of Progress: What We've Learned About Autism' (see here). Cumulatively, these two commentaries try to paint a picture of where we are, knowledge-wise, when it comes to the label of autism or autism spectrum disorder (ASD) and highlight the many gaps that remain in what we 'think' we know about autism.

The Chen paper approaches the 'emerging picture of autism' theme from the point of view of genetics and neuropathology (the paper title talks about pathology but as per quite a lot of autism research, the idea that autism might extend beyond the grey-pink matter floating inside our skull is still a bit of a research novelty in some quarters). The authors talk about a "number of recent breakthroughs" which have advanced our understanding of autism; more specifically in relation to genes and neuropathology.

The Autism Speaks commentary lists the research achievements that the organisation has been involved with over the decade of its operations. Interestingly, their focus is not just on genes and/or the brain, but a rather more broader view of autism covering issues such as comorbidity (epilepsy and somatic issues such as bowel function), diagnosis and intervention, and real-life events such as the issues of wandering and the lack of employment opportunities [2] for many on the spectrum. The focus is more practical; more functional if you like.

What I think both these commentaries do, is show how we have advanced our knowledge base when it comes to the diagnostic label that is autism, the ways and means it can potentially come about and the very real effects that it can have on a person and those around them. Appreciating for example, that the genetics of autism (if that is what I can currently call them) are not everyone's cup of tea, indeed that also Autism Speaks is not everyone's cup of tea, the collected message is that progress is being made, albeit with quite a lot more to do specifically with a focus on 'translating science into practice'. The paper from Politte and colleagues [3] (open-access) lists quite a bit of that progress and what it means for something like intervention.

I'm going to add a few other points to the question of 'what have we learned about autism?' based on my very humble reading of the research literature over the past few years. Here goes...

The autisms (plural)
First, the concept of 'the autisms' as a potential replacement for a single unifying idea of what autism might be. Regular readers have probably heard me talk about the plural autisms for a while on this blog on the basis of differing developmental trajectories being reported (see here) and the various different pathways that have been described as potentially leading to a diagnosis of autism (see here and see here). The recent paper from Yuen and colleagues [4] on siblings and genetic diversity in autism (see here) adds to the sentiments of plural autisms.

Trajectories and outcome
Second is the idea that because there may be quite a few developmental trajectories associated with autism, for at least some people in receipt of a diagnosis of autism, that diagnosis might not necessarily be as 'life-long' as was once thought. I speak of course about the work from Deborah Fein and others on the concept of optimal outcome and autism (see here) and the idea that some people/children do not fulfil the diagnostic criteria after having previously received a diagnosis. I appreciate that optimal outcomes has been a contentious topic at times, but other research highlighting similar processes [for some] potentially pertinent to a diagnosis of Asperger syndrome (see here) for example, cannot be readily ignored through fear of dogma or clinical / societal implications. Indeed, when it comes to the possibility that autism may, on occasion, morph into other clinical descriptions (see here), the idea of close and regular monitoring becomes pretty important.

Comorbidity clusters
Third, expanding the notion that a diagnosis on the autism spectrum might elevate the risk of other comorbid conditions also appearing, is the idea that we need to move away from the label as appearing in some sort of diagnostic vacuum. I've lost count of the amount of times both behavioural and/or somatic comorbidity has been linked to autism outside of the more classical examples of learning disability (see here) and epilepsy/seizure-type disorders (see here). Anxiety and depression have also received quite a lot of research attention in recent times (see here and see here respectively). I've always tended to view things such as epilepsy as comorbidity but as per other commentators, I'm now starting to move towards the view that where present, seizure or seizure disorders is perhaps a more central part of some 'types' of autism. I'll admit that the prospect of categorising autism on the basis of presented symptoms, developmental trajectory, presence of non-autism related pathology and response (or not) to certain interventions is a daunting one, potentially coming up with hundreds of different combinations. Much of this harks back to the work of people such as Isaac Kohane and colleagues and their 'comorbidity' clusters (see here). But if that is what the science is starting to indicate, maybe we should be making greater moves towards the idea that autism is a lot more complex than anyone had possibly imagined.

Exercise
Finally, I'd like to think that as autism research progresses we are starting to become a lot more aware of the physical and mental health and wellbeing of those on the autism spectrum. With all the various research findings on this, that and t'other in relation to autism, it's sometimes easy to lose sight of issues like the importance of exercise or healthy eating for those on the autism spectrum as for everyone else. Exercise and physical activity is something I've become particularly conscious of when it comes to autism. Whilst everyone (including me) have been wowed by the impact of technology on autism, I do wonder what this increasing screen time means for rates of physical activity for people on the autism spectrum. Sedentary behaviour and physical activity has turned up a few times in my writings on this blog (see here and see here) and the idea that we perhaps need to be promoting these a little more for some people on the spectrum. I'm not necessarily advocating turning people into the next Ironman / Ironwoman or Bruce Lee (see here) but just doing enough to ensure that the growing obesity issue does not further disadvantage people on the autism spectrum.

That's me done. Now for some music: Palma Violets and Best of Friends.

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[1] Chen JA. et al. The Emerging Picture of Autism Spectrum Disorder: Genetics and Pathology. Annu Rev Pathol. 2015 Jan 24;10:111-144.

[2] Baldwin S. et al. Employment activities and experiences of adults with high-functioning autism and Asperger’s Disorder. J Autism Dev Disord. 2014 Oct;44(10):2440-9.

[3] Politte LC. et al. Evidence-Based Treatments for Autism Spectrum Disorder. Current Treatment Options in Psychiatry. 2015. Jan 30.

[4] Yuen RK. et al. Whole-genome sequencing of quartet families with autism spectrum disorder. Nat Med. 2015 Jan 26.

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Chen JA, Peñagarikano O, Belgard TG, Swarup V, & Geschwind DH (2015). The Emerging Picture of Autism Spectrum Disorder: Genetics and Pathology. Annual review of pathology, 10, 111-144 PMID: 25621659

Diverse developmental trajectories in early years autism

"Findings confirm the heterogeneous nature of developmental trajectories in ASD [autism spectrum disorder]." That was the bottom line of the study by Peter Szatmari and colleagues [1] (open-access) tracking the developmental trajectory - autistic symptom severity and adaptive functioning - for a sample of "421 newly diagnosed preschool children with ASD 2 to 4 years old." Some accompanying media for the study can be found here.

The Szatmari paper is open-access so it doesn't need any grand details from me... OK, well just a few:

• "Prospective data collected at 4 points from time of diagnosis to age 6 years were used to track the developmental trajectories of children." 
• Old reliable ADOS (Autism Diagnostic Observation Schedule) was used "to index the developmental trajectories of autistic symptom severity" alongside the VABS (Vineland Adaptive Behavior Scales) which "assesses child adaptive behavior in the communication, socialization, daily living skills, and motor domains." The immediate difference between these schedules outside of looking at autism symptoms and adaptive behaviours is the reliance on observer scores and parent/caregiver report respectively. Just in case you were worried, the timing gaps between ADOS sessions for example, were probably large enough so as not to lead to any so-called practice effects impacting results. Other psychometric tools were also used to gauge 'trajectory prediction and outcome' including the ADI (Autism Diagnostic Interview) among other things.
• Results: outside of the heterogeneity of symptom presentations, a few key points were noted. So: "Individual children with ASD differ from each other in terms of autistic symptom severity and adaptive functioning from the time of diagnosis in the preschool years, and some of these differences appear to increase by age 6 years." Interesting but not exactly a novel finding as per other discussions in this area (see here).
• "Moreover, change in one domain is not necessarily associated with change in another." In other words, about 20% of their sample showed changes in "adaptive functioning trajectories" indicative of improvement. But that doesn't necessarily translate into similar changes in autistic presentation which were reported to be "more stable" although in about 10% of cases showing "a decrease in symptom severity from baseline to age 6 years."
• In all, the authors report two distinct trajectory groups based on autism severity and three groups for adaptive functioning. 
• Caveats? Well, this was a multi-site study in Canada but following diagnosis, participants were not just left without intervention. The Hanen More Than Words® intervention is mentioned as being offered at one site. Indeed the authors note: "the present analysis did not investigate the possible effect of services or opportunities to learn adaptive functioning skills on the developmental trajectories of children with ASD" so one has to be mindful that the results reported might be affected by this variable. Indeed, one would expect trajectory to be potentially affected by such early intervention...

This is interesting work particularly from the perspective of being a longitudinal study which relied on some of the gold-standard tools available to autism psychometric research. I'm really interested in developmental trajectory and autism in light of this area of research highlighting how autism is perhaps better described as the more plural 'autisms' and the breaking down of some sweeping generalisations and dogma which have pervaded autism understanding. That also one or more trajectory might come under the label of 'optimal outcome' (see here), that is moving outside of the diagnostic boundaries of the clinical description of autism, is another important part of this work. Oh, and just in case you think such ideas are bound to just children, think again (see here).

Gender (sex) is also mentioned in the Szatmari paper and the idea that "sex was the only significant predictor of autistic symptom group trajectory membership." The authors continue: "Boys were more likely to be in the group with more severe symptoms and a stable trajectory than girls, who were more likely to be in the group with less severe symptoms and an improving trajectory (controlling for age at diagnosis, cognitive and language scores, and site)." This is really quite an interesting observation and perhaps ties into the idea of sex differences in the presentation of autism (see here) among other things. I'd be interested to see how the gender splits pan out when it comes to those optimal outcomers too as and when larger participant numbers are eventually meta-analysed by someone.

Finally: "earlier age at diagnosis was more likely associated with membership in a group with higher functioning and improving." Going back to my previous point about a possible role for early intervention in developmental trajectory, the idea that earlier diagnosis can make a difference through the use of earlier intervention also potentially gains ground from such observations. Early diagnosis is a primary endpoint for quite a lot of autism research (see here) although with still quite a bit to do in this area (see here).

The Hurdy Gurdy Man to close from The "B.H. Surfers".

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[1] Szatmari P. et al. Developmental Trajectories of Symptom Severity and Adaptive Functioning in an Inception Cohort of Preschool Children With Autism Spectrum Disorder. JAMA Psychiatry. 2015. Jan 28.

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Szatmari, P., Georgiades, S., Duku, E., Bennett, T., Bryson, S., Fombonne, E., Mirenda, P., Roberts, W., Smith, I., Vaillancourt, T., Volden, J., Waddell, C., Zwaigenbaum, L., Elsabbagh, M., & Thompson, A. (2015). Developmental Trajectories of Symptom Severity and Adaptive Functioning in an Inception Cohort of Preschool Children With Autism Spectrum Disorder JAMA Psychiatry DOI: 10.1001/jamapsychiatry.2014.2463

The Autism-Spectrum Quotient: overlap between Asperger syndrome and schizophrenia

The paper by Tove Lugnegård and colleagues [1], including mention of one Maria Unenge Hallerbäck who has appeared on this blog previously, is fodder for today's discussions and their finding that a: "significant overlap of AQ [Autism-Spectrum Quotient] scores across the two diagnostic groups clearly reduces the discriminating power of the AQ in the separation of schizophrenia from AS [Asperger syndrome]."

They say you're judged by the strength of your enemies.

As per that link to previous work by Unenge Hallerbäck among others, the idea that the autism spectrum and the schizophrenia spectrum might not be as separate and independent as is commonly thought is gaining some renewed research momentum in recent times (see here). I wouldn't necessarily call it a reunification, as per older sentiments of autism being akin to childhood schizophrenia despite the fact that some of the criteria produced for example, by Mildred Creak and colleagues, contain some potentially pertinent information (see her 9 key features of ‘schizophrenic syndrome in childhood’).

Rather however a realisation that (a) autism is nothing like protective against the subsequent development of schizophrenia or related diagnoses particularly with a changing symptom profile moving into adulthood, and (b) in these days of RDoC (see here), common genetic / epigenetic / biological / behavioural ground may be evident across some cases of autism and some cases of schizophrenia including something of familial element [2]. The fact that Prof. Gillberg also makes an appearance on the Lugnegård paper adds to the ESSENCE of overlapping comorbidity (see here) or autism plus [3] if you so wish.

Back to the recent Lugnegård study, and based on quite a bit of work in this area by the authors (see here), they aimed to: "examine the AS-schizophrenia discriminating ability of the AQ." The AQ for those that might not know, represents a series of questions/statements scored on the basis of the presence (or not) of specific cognitive-behavioural traits noted as part of the autism spectrum. It's been talked about a few times on this blog in relation to looking at sensory issues in autism (see here) and rather more uncomfortably, suicide ideation/attempts with parts of the autism spectrum in mind (see here).

The AQ "was completed by 136 individuals: 36 with schizophrenic psychosis, 51 with AS and 49 non-clinical comparison cases." The results: well, as a group, those with AS did score significantly higher than the schizophrenia group, who scored higher than the asymptomatic control group. That being said, there was quite a bit of overlap in the range of AQ scores obtained across the groups and particularly when it came to those with AS and those with schizophrenia. Ergo, using one of the more popular self-report measures for autism, some on the schizophrenia spectrum might also present with a prominent level of autistic traits as part of their symptom profile.

Obviously one has to be slightly cautious with such findings. Self-report is subject to quite a few forms of bias; to some degree complicated by the questions and grading system used by the AQ (take the test here if you wish) which is very subjective in itself (e.g. " I prefer to do things with others rather than on my own" - in what context... going for a drink, taking a bath, etc.). That being said, papers such as the one by Shaun Eack and colleagues [4] (open-access) reporting "considerable similarity in social and non-social cognitive impairment in verbal adults with ASD and outpatients with schizophrenia" under more controlled conditions, offer something of a complementary viewpoint to the Lugnegård and other findings. And before you ask, such overlap in presentation might not just be accounted for by other comorbidity either [5].

Appreciating that diagnostic identity is still an important part of both autism and schizophrenia spectrums for all-manner of different reasons, the idea of compartmentalising when it comes to diagnostic labels is seemingly on less secure ground that it has been for many years. Fuzzy diagnostic boundaries intra-diagnosis - y'know the heterogeneity of the spectrums - has been further complicated by fuzzy diagnostic boundaries inter-diagnosis. And things are only likely going to get even more complicated as per the paper by Song and colleagues [6] for example...

And now for some music... Duck Sauce - Barbra Streisand

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[1] Lugnegård T. et al. Asperger syndrome and schizophrenia: Overlap of self-reported autistic traits using the Autism-spectrum Quotient (AQ). Nord J Psychiatry. 2014 Nov 12:1-7.

[2] Sullivan PF. et al. Family History of Schizophrenia and Bipolar Disorder as Risk Factors for Autism. Arch Gen Psychiatry. 2012;69(11):1099-1103.

[3] Gillberg C. & Fernell E. Autism plus versus autism pure. J Autism Dev Disord. 2014 Dec;44(12):3274-6.

[4] Eack SM. et al. Commonalities in social and non-social cognitive impairments in adults with autism spectrum disorder and schizophrenia. Schizophr Res. 2013 Aug;148(1-3):24-8.

[5] Mealey A. et al. Overlap between autistic and schizotypal personality traits is not accounted for by anxiety and depression. Psychiatry Res. 2014 Oct 30;219(2):380-5.

[6] Song DK. et al. Comparative analysis of autistic traits and behavioral disorders in Prader-Willi syndrome and Asperger disorder. Am J Med Genet A. 2014 Nov 11.

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Lugnegård T, Hallerbäck MU, & Gillberg C (2014). Asperger syndrome and schizophrenia: Overlap of self-reported autistic traits using the Autism-spectrum Quotient (AQ). Nordic journal of psychiatry, 1-7 PMID: 25389915

UK Millennium Cohort Study: School and the disabled child

Quite recently the BBC News online ran with the headline: "Disabled children's behaviour 'deteriorates at school'". The story revolved around the findings reported by Rebecca Fauth and colleagues [1] (open-access) looking at "the extent to which the associations between disability and behaviour are linked to children’s developmental stage and thus may be ‘grown out of’ as children enter school and move out of the early years". I should add that, at the time of writing, the Fauth paper is described as a 'working paper' and further "Citation of such a paper should account for its provisional character". So noted.

But why Earth, Jor-El? They're primitives...

With apologies for all the quotations included in this entry, participants for this trial were drawn from the UK Millennium Cohort Study (MCS) [2] which has previously reported on the topic of autism [3] - "Pre-diagnostic data showed early health problems differentiated children later diagnosed with autism from non-diagnosed peers" - Mmm.

In the Fauth paper it included over 6000 UK children covering various ages at different times over the course of the study (referred to as 'sweeps'). Children without reported disability were compared against 3 primary groups defined as 'disabled':

• Children with developmental delay (DD) at 9 months of age. This was assessed via "a set of 8 questions... that were taken from the Denver Developmental Screening Test" and "five items from an UK adaptation of the MacArthur Communicative Development Inventories (CDI) were used to identify early communicative gestures".
• Children with a "Long-standing limiting illness [LSLI] at 3, 5 or 7 years". LSLI was defined "if they had an LSLI at one or more of the occasions it was asked between age 3 and age 7" and included various conditions covering 'mental health' and physical health (asthma, type 1 diabetes and vision impairment).
• Children with Special Educational Needs (SEN) at age 7. Those familiar with the UK system will probably already know about SEN, but for those that don't, it covers "those children who need additional support with their learning" (see here). Further: "SEN may relate to learning difficulties or impairments such as hearing loss, ADHD or dyslexia".

Researchers tracked participants looking at various measures covering areas of "children's emotional, relationship and behavioural issues at the ages of three, five and seven" according to the BBC report. Fauth and colleagues list the dependent variables as being derived from "the four ‘problem’ subsets of the parent-reported Strengths and Difficulties Questionnaire (SDQ)". They also took into account various other factors based on family background and constitution, the parent-child relationship (including discipline practices) and child characteristics.

Based on some nifty statistical modelling, the authors reported on a few key points:

• So: "in their early preschool years disabled children do suffer from more challenging expressions of behaviour". 
• With some caveats: "disabled children exhibit a divergent trajectory from the ‘average’ child, showing increases over time in peer problems, hyperactivity and emotional problems, but not for conduct problems".
• Also: "family and individual characteristics that are associated with both disability and behaviour (such as poverty, family structure, cognitive ability and home environment) mediate the effects of disability in these instances".
• The authors talk about sex differences in their results: "overall girls face lower levels of peer, conduct and hyperactivity behavioural problems across the early years than boys". This is perhaps not an unexpected result as any parent with both boys and girls will perhaps tell you. But: "disabled boys consistently demonstrated more hyperactive problems than non disabled boys, and that these differences grew over time for boys with LSLI and SEN". Additionally: "The differences between disabled and non-disabled children is much greater for boys than for girls, and this divergence between disabled and non-disabled boys grows more over time than it does for girls".
• Parenting styles also get a mention in the results: "harsh discipline being consistently associated with higher levels of problem behaviours, and parent-child closeness being linked to lower rates of problem behaviours". With disability in mind however, the authors saw: "very little evidence of parenting moderating the relationship between disability and problem behaviours, either at age 3 or over time".

I should also add that when it came to looking at developmental delay (DD) the authors noted: "the developmental trajectories of children identified as DD did not diverge from those without DD" although measurement of peer and hyperactivity issues for example, did still not 'close the gap' compared with non-DD participants.

The authors conclude: "Child behavioural difficulties can have far reaching consequences and hence, without appropriate support or intervention, young disabled children may face an accumulation of adverse consequences that serve to compromise their well-being in adolescence and adulthood".

I'm sure you can appreciate how important this work is in terms of both how disability impacts on childhood and what strategies might be put in place to reduce some of the more adverse effects of such issues and lessen any inequality as a result. I note for example, that the BBC write-up of this research has given quite a lot of weight with regards to bullying and the notion that schools should adopt "more stringent anti-bullying strategies for those identified as different" as a result of the findings. I would very much agree with this position; with the caveat of ensuring that children with disability are not further plunged into the 'victim' label as a result of any strategies. This can sometimes itself have consequences for things like future independence and self-esteem; thus helping individuals to help themselves - instilling confidence and resilience and building up feelings of self-worth - is another strand to any discussions (and I have a few ideas on that without making any sweeping generalisations). I'm also wondering whether the debate on home-schooling might also come into play here too?

I'd finally also like to pass some comment about the issue of parenting styles discussed in the findings. Although no large effect appeared to be observed from parenting style and problem behaviours in those with disability, the more general association between harsh parenting style and hyperactive behaviours for example, offers a fascinating opportunity and potentially offers some, more general lessons on child development and rearing. I might add that the parenting style - disability non-event - "does not have much role in modifying the specific trajectories of problem behaviours associated with disability" - might also carrying some lessons for particular conditions like autism for example too (see here).

Now, how about looking at other potential mediators of behaviour such as adequate sleep [4], regular exercise and good nutrition [5] (including a possible role for supplementation)? Too much...?

Music to close. Love Me Like You from the Magic Numbers (although my brood prefer their cameo performance in the Harry Hill Movie...)

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[1] Fauth R. et al. Convergence or divergence? A longitudinal analysis of behaviour problems among disabled and non-disabled children aged 3 to 7 in England. Department of Quantitative Social Science. Institute of Education, University of London. Working Paper No. 14-13. Sept 2014.

[2] Connelly R. & Platt L. Cohort Profile: UK Millennium Cohort Study (MCS). Int J Epidemiol. 2014 Feb 17.

[3] Dillenburger K. et al. he Millennium child with autism: Early childhood trajectories for health, education and economic wellbeing. Dev Neurorehabil. 2014 Oct 7:1-10.

[4] Lee HK. et al. Sleep and cognitive problems in patients with attention-deficit hyperactivity disorder. Neuropsychiatr Dis Treat. 2014 Sep 17;10:1799-805.

[5] Bellisle F. Effects of diet on behaviour and cognition in children. Br J Nutr. 2004 Oct;92 Suppl 2:S227-32.

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Connelly R, & Platt L (2014). Cohort Profile: UK Millennium Cohort Study (MCS). International journal of epidemiology PMID: 24550246