'Flash, ah-ahh'. Flash Gordon. You remember him, and that fantastic film in 1980 with the soundtrack by Queen. Max von Sydow played Ming the Merciless who ruled Mongo with a iron fist. 'All hail Ming, Ruler of the Universe' was the chant from his (dis)loyal subjects. Well, Ming might well have been Ruler of the Cosmos, but us humans may very well bow down to another Ruler - or should I say a couple of trillion Rulers - our endogenous gut bacteria.
Despite my previous posts examining a possible relationship between some cases of autism spectrum conditions and 'abnormal' gut bacteria, this post is a little different. Different because it is not looking at gut bacteria in relation to autism per se, but rather some wider research.
Before I start, I want to acknowledge a few sources of information including Emily Deans over at Evolutionary Psychiatry, Maff at the Environmental Illness Resource and the Neurophilosophy blog (I don't want any charges of plagiarism levelled against me).
My attention was turned to two papers published recently on a possible bi-directional relationship between gut bacteria and behaviour in mice. By bi-directional, I mean that gut bacteria could influence behaviour and behaviour could influence gut bacteria. OK I hear you cry, fine if you are a mouse - and you would be absolutely right. But remember that mice are used to build a variety of different models of human functioning including that related to autism (see special edition of the Autism Research journal on mouse models).
Both the papers highlighted have generated quite a bit of discussion on their various implications.
The paper suggesting that behaviour (in this case, stress) can affect gut bacterial populations implies a few things: (a) gut bacterial populations are dynamic and responsive to our psychology and/or behaviour as well as more physiologically-determined variables such as medication or diet, (b) where gastrointestinal conditions are present and potentially tied into gut bacteria (IBS for example), the mechanism for psychosocial stress impinging on symptoms may well be tied in. This last point in particular may have some relevance for specific cases of autism spectrum conditions where stress and arousal seem to be common. Think also to my recent post covering probably the most undesirable therapy ever invented, fecal transplantation and the implications of a comment posted in jest on the EP blog "..if you ever have a fecal transplant, make sure it is from a slender, non-asthmatic, happy person!".
The other paper detailing the effect of gut bacteria (or lack of it) on behaviour seems to tie in with the growing interest in such a relationship related to autism. Remember that study from Richard Sandler and colleagues from 2000 where short-term administration of a powerful antimicrobial acting on gut bacteria (I assume!) led to some short-term positive behavioural changes in children with autism?
As per the ethos of this blog I have tried to tie the work back to autism, but really these papers potentially show some applicability to lots of different areas. ME/CFS perhaps? How about what happens when we try and change/affect our gut bacterial populations? What happens to behaviour?
This paper was published a few years back and tried just that. Using a double-blind, placebo-controlled methodology, the authors looked at what happened to anxiety symptoms in participants with CFS when a probiotic preparation was taken. The results: a rise in the 'good' bacteria (aerobic predominantly) and a decrease in anxiety symptoms when taking the probiotic over the placebo. Let's be straight though. I am not saying that such an intervention will help everyone with every condition. But all these papers tell us that perhaps we should be looking at our gut bacterial populations a little more closely from a research perspective.
All hail the gut bacteria, ruler of OUR Cosmos!
Monday, 4 April 2011
Sunday, 3 April 2011
Autism and PUBERTY!
It is the one thing that everyone goes through and don't we all know it. Nature probably had a smirk on its face when it thought up puberty. That transitionary period where girl becomes woman and boy becomes man. Acne, mood swings, and lots of physical changes - hair everywhere.
Puberty always reminds me of Harry Enfield's Kevin the teenager and his over-used catchphrases to his parents 'I hate you', 'it's so unfair'. An illustration whereby the physical body is shouting 'grow up!' but more often than not, the mind is a little way behind (or is it the other way around?).
There is no doubt about it, puberty can be a really rough time for lots of children and their parents. For a child diagnosed with an autism spectrum condition, puberty has been described as bringing its own set of new challenges.
I remember the discussions with our collaborating partners whilst working on the ScanBrit trial of a gluten- and casein-free diet for autism. When it came to deciding the age range of our participant group, there was lots of chatter but only one message - avoid puberty.
The reason why so many studies and research avoid puberty when evaluating things like interventions is partly to do with a leaning towards assessing early interventions for young children with autism and partly because there is quite a lot of evidence to suggest that puberty for children with autism can be a bit of a torrid time and will potentially play havoc with any study results obtained (tip: best way to show that something does not work, study it during puberty!).
One of the first people to investigate autism and puberty was Christopher Gillberg. In one of the first papers on the subject, Gillberg discussed how autistic symptoms were negatively affected by puberty in a case series investigation. His follow-up work down the years has presented a similar message; a message that has been echoed by others. The message is that puberty, more often than not, tends to increase (worsen?) the presentation of various autistic symptoms.
At this point, most people would probably say 'what did you expect?' bearing in mind what puberty does to children who do not have autism e.g. questioning authority, wanting to spend more time alone, wanting to be more independent. Mmm - sounds like the border regions of 'challenging behaviours' to me - I jest of course.
But question more closely the details of puberty in relation to autism.
Puberty is all about hormones driving maturational changes. Hormones such as oestrogen and testosterone (testosterone.. I've heard that somewhere before related to autism). Within this period (pardon the term) of hormonal soup, are we saying that 'puberty affects autism' or does puberty merely affect a child with autism the same way is does a child without autism but is further complicated by the presence of autism (and any other comorbidities)?
There is some interesting research being done, directly and peripherally, in is this area.
It appears that there is a potential link between some cases of autism and onset of various comorbidity following puberty. Likewise, various mechanisms linked to autism have been suggested to 'intensify' as a result of puberty including those related to epilepsy.
Peripherally also, it seems that there is some evidence that important compounds such as serotonin (5-HT) don't seem to show the same maturational patterns in autism as in non-autism - is this an effect of puberty?
I don't think there is anything that can be done to 'get' around puberty - nothing that ethically we would want to use anyway - and so like not-autism, it is mainly a case of 'grin and bear it'. The light at the end of the tunnel is that, whilst disruptive, puberty does not last forever; and as many authors have noted, culturally-speaking, puberty is an important rite of passage into adulthood.
Puberty always reminds me of Harry Enfield's Kevin the teenager and his over-used catchphrases to his parents 'I hate you', 'it's so unfair'. An illustration whereby the physical body is shouting 'grow up!' but more often than not, the mind is a little way behind (or is it the other way around?).
There is no doubt about it, puberty can be a really rough time for lots of children and their parents. For a child diagnosed with an autism spectrum condition, puberty has been described as bringing its own set of new challenges.
I remember the discussions with our collaborating partners whilst working on the ScanBrit trial of a gluten- and casein-free diet for autism. When it came to deciding the age range of our participant group, there was lots of chatter but only one message - avoid puberty.
The reason why so many studies and research avoid puberty when evaluating things like interventions is partly to do with a leaning towards assessing early interventions for young children with autism and partly because there is quite a lot of evidence to suggest that puberty for children with autism can be a bit of a torrid time and will potentially play havoc with any study results obtained (tip: best way to show that something does not work, study it during puberty!).
One of the first people to investigate autism and puberty was Christopher Gillberg. In one of the first papers on the subject, Gillberg discussed how autistic symptoms were negatively affected by puberty in a case series investigation. His follow-up work down the years has presented a similar message; a message that has been echoed by others. The message is that puberty, more often than not, tends to increase (worsen?) the presentation of various autistic symptoms.
At this point, most people would probably say 'what did you expect?' bearing in mind what puberty does to children who do not have autism e.g. questioning authority, wanting to spend more time alone, wanting to be more independent. Mmm - sounds like the border regions of 'challenging behaviours' to me - I jest of course.
But question more closely the details of puberty in relation to autism.
Puberty is all about hormones driving maturational changes. Hormones such as oestrogen and testosterone (testosterone.. I've heard that somewhere before related to autism). Within this period (pardon the term) of hormonal soup, are we saying that 'puberty affects autism' or does puberty merely affect a child with autism the same way is does a child without autism but is further complicated by the presence of autism (and any other comorbidities)?
There is some interesting research being done, directly and peripherally, in is this area.
It appears that there is a potential link between some cases of autism and onset of various comorbidity following puberty. Likewise, various mechanisms linked to autism have been suggested to 'intensify' as a result of puberty including those related to epilepsy.
Peripherally also, it seems that there is some evidence that important compounds such as serotonin (5-HT) don't seem to show the same maturational patterns in autism as in non-autism - is this an effect of puberty?
I don't think there is anything that can be done to 'get' around puberty - nothing that ethically we would want to use anyway - and so like not-autism, it is mainly a case of 'grin and bear it'. The light at the end of the tunnel is that, whilst disruptive, puberty does not last forever; and as many authors have noted, culturally-speaking, puberty is an important rite of passage into adulthood.
Saturday, 2 April 2011
Are savant skills more likely in males with autism?
The impact of the 1988 film 'Rainman' on autism awareness has been pretty significant I would say. The Oscar winning film portrayed one 'type' of autism fairly well I think; certainly, the film received quite a bit of acclaim back in the day. One could even perhaps say that the film was influential in bringing autism awareness to a mainstream audience during the late 1980's (although there have been other notable events also).
I do however stress the one 'type' of autism presented in the film, because, as many people down the years have said, the sort of savant skills that were depicted in the film, are perhaps not entirely representative of everyone with autism.
I mention all this because of a new paper from the world famous Karolinska Institute in Sweden has been published titled: Sex differences in cognitive domains and their clinical correlates in higher-functioning autism spectrum disorders. I only have the abstract of the paper at the moment but I was interested in what they did and what they found.
Basically, the authors looked at attention-to-detail and selected executive functions between males and females with and without autism. They found some sex differences: predominantly that males were perhaps better on measures relating to attention-to-detail as measured by the block design test. The authors interpreted this as being potential evidence for a sex difference in savant skills skewed towards males.
Their results are not alone in suggesting the possibility of a stronger tendency towards savant skills in males over females. A few years back Prof. Sir Michael Rutter suggested the same thing and it was mentioned in this overview article.
It did get me thinking about the possible reasons for such gender disparity in the presentation of savant skills. Is it due to the presentation of symptoms differing between the genders? Are males inherently more likely to be savants or are there other environmental factors contributory? In Yoda speak: "answers I do not have to these questions".
My train of thought then led to the question of defining savant skills and whether our perception of what is, or is not, a savant skill might also be contributory to such a sex disparity. I note on the Wikipedia entry for savant syndrome quite a few people are listed - males and females - although again, noticeably skewed towards more males than females.
The person I most remember from my early recollections of autism was Stephen Wiltshire, and his fantastic drawings of various landmarks which aired on Blue Peter here in the UK.
Notable also on this list is Temple Grandin and her influential work on animal husbandry (timely also that her biopic is on TV here in the UK tomorrow and, no doubt, will stimulate more interest in autism).
I do however stress the one 'type' of autism presented in the film, because, as many people down the years have said, the sort of savant skills that were depicted in the film, are perhaps not entirely representative of everyone with autism.
I mention all this because of a new paper from the world famous Karolinska Institute in Sweden has been published titled: Sex differences in cognitive domains and their clinical correlates in higher-functioning autism spectrum disorders. I only have the abstract of the paper at the moment but I was interested in what they did and what they found.
Basically, the authors looked at attention-to-detail and selected executive functions between males and females with and without autism. They found some sex differences: predominantly that males were perhaps better on measures relating to attention-to-detail as measured by the block design test. The authors interpreted this as being potential evidence for a sex difference in savant skills skewed towards males.
Their results are not alone in suggesting the possibility of a stronger tendency towards savant skills in males over females. A few years back Prof. Sir Michael Rutter suggested the same thing and it was mentioned in this overview article.
It did get me thinking about the possible reasons for such gender disparity in the presentation of savant skills. Is it due to the presentation of symptoms differing between the genders? Are males inherently more likely to be savants or are there other environmental factors contributory? In Yoda speak: "answers I do not have to these questions".
My train of thought then led to the question of defining savant skills and whether our perception of what is, or is not, a savant skill might also be contributory to such a sex disparity. I note on the Wikipedia entry for savant syndrome quite a few people are listed - males and females - although again, noticeably skewed towards more males than females.
The person I most remember from my early recollections of autism was Stephen Wiltshire, and his fantastic drawings of various landmarks which aired on Blue Peter here in the UK.
Notable also on this list is Temple Grandin and her influential work on animal husbandry (timely also that her biopic is on TV here in the UK tomorrow and, no doubt, will stimulate more interest in autism).
Friday, 1 April 2011
Is 'gut health' entering mainstream medicine?
A short post this one following quite a few busy evenings of blogging.
My BMC alerts are certainly paying dividends with the papers they are revealing. Today I received another paper from BMC Medicine titled: 'Gut health': a new objective in medicine?
The paper, which is my favourite kind, open-access, is from this chap and is a review article on the various workings of the gut, including gut barrier function, tied into various biological systems and diseases/conditions. It serves as quite a good overview of gut function and mentions quite a bit about pharmcotherapeutics in relation to the gut. Importantly also is the discussion on the gut microflora; which quite nicely reminds me of a new post in the pipeline for this blog coming up in the next few days (oh he's such a self-publicist!)
Anyway, enjoy the article.
My BMC alerts are certainly paying dividends with the papers they are revealing. Today I received another paper from BMC Medicine titled: 'Gut health': a new objective in medicine?
The paper, which is my favourite kind, open-access, is from this chap and is a review article on the various workings of the gut, including gut barrier function, tied into various biological systems and diseases/conditions. It serves as quite a good overview of gut function and mentions quite a bit about pharmcotherapeutics in relation to the gut. Importantly also is the discussion on the gut microflora; which quite nicely reminds me of a new post in the pipeline for this blog coming up in the next few days (oh he's such a self-publicist!)
Anyway, enjoy the article.
On the Hippocratic Oath
I have more than a passing interest in all things Greek - particularly the language, which I have been learning for the past 10 years or so, and the history. When I say history, I am not talking so much about recent history, more the Classical period; the time when Greece was truly the cradle of modern European Civilisation.
One figure in particular is of interest: Hippocrates of Kos. Hippocrates (pronounced Hipp-o-kra-tees not hippo-crates - a la Bill and Ted and their colourful use of 'So-crates'!) was a physician, or at least the Classical equivalent to a physician, often referred to as the Father of Modern Medicine.
What did he do? Well he is credited with bringing medicine out of the realm of superstition and into a more real-world way of thinking with such notions as disease being caused by natural phenomena. One might say he is one of the first people to bring evidence-based practice to the forefront. There are quite a lot of other things he did and, assuming you have the time, I could recommend finding out more about his, and his students, teachings.
One of the more notable achievements of Hippocrates (or at least ascribed to Hippocrates and his followers) was the introduction of a code to which physicians subscribe to as part of their license to practice Medicine. The Hippocratic Oath forms the fundamental moral and ethical guidelines for practicing Medicine. For those lucky enough to be able to read Ancient and/or Modern Greek, excerpts of the original texts can be found here.
Whilst not a medical Physician myself, I have taken a little time to study what the Oath says and potentially implies. Herein I share some interesting parts of said Oath.
Depending on which version is used, there are some interesting points to be made.
First, the language used. Throughout all versions of the Oath there is use of the word 'art'. The various versions posted on Wikipedia (original, classic and modern) all contain 'art' and implicitly imply that medicine, whilst being science is also part art. I have to say that against all my scientific training and background, I do kinda like this. I like it because it suggests that science can take Medicine so far, but art perhaps takes it that little bit further. Importantly, it puts physicians in the driving seat when it comes to the care they provide for individuals perhaps differing from person to person. This article says pretty much the same. Remember also my post on autism and n=1?
Second, the Oath acknowledges that physicians, whilst respected for their science and their art, are not infallible. To quote from the modern text: "I will not be ashamed to say that I know not..". I think it is a mark of great strength when someone can admit that they don't know something and ask advice from those who might. This part of the Oath directs physicians to do just that.
Third, the Oath talks about treating 'people' not diseases or conditions. In these modern times, where finances for healthcare are being squeezed and contact time with patients is an issue to meet targets (certainly here in the UK), it is perhaps important to step back and understand that the patient is key, not the condition, disease, injury or state. The implication for autism for example is that 'underneath' the presentation of symptoms is a person (and their family, as also discussed in the Oath) and that the duty of care is to that person, whatever care they may or may not require either as a result of their autism or resultant from any associated co-morbidity.
Finally, the modern Oath quotes: "Above all, I must not play at God". Medicine has seen a few examples of physicians trying to play God. Here in the UK we had Dr Harold Shipman not so long ago; lest we forget his victims that ran into the hundreds in numbers. Away from just mortality (which this sentence of the Oath is specifically focused on) the message here is that physicians have an extremely important responsibility over their patients and their care; a responsibility that resonates throughout the medical and peripheral professions.
Some final words from a protagonist in our friendly neighbour-hood Spiderman movie (or was it Chris Eubank): "With great power comes great responsibility".
One figure in particular is of interest: Hippocrates of Kos. Hippocrates (pronounced Hipp-o-kra-tees not hippo-crates - a la Bill and Ted and their colourful use of 'So-crates'!) was a physician, or at least the Classical equivalent to a physician, often referred to as the Father of Modern Medicine.
What did he do? Well he is credited with bringing medicine out of the realm of superstition and into a more real-world way of thinking with such notions as disease being caused by natural phenomena. One might say he is one of the first people to bring evidence-based practice to the forefront. There are quite a lot of other things he did and, assuming you have the time, I could recommend finding out more about his, and his students, teachings.
One of the more notable achievements of Hippocrates (or at least ascribed to Hippocrates and his followers) was the introduction of a code to which physicians subscribe to as part of their license to practice Medicine. The Hippocratic Oath forms the fundamental moral and ethical guidelines for practicing Medicine. For those lucky enough to be able to read Ancient and/or Modern Greek, excerpts of the original texts can be found here.
Whilst not a medical Physician myself, I have taken a little time to study what the Oath says and potentially implies. Herein I share some interesting parts of said Oath.
Depending on which version is used, there are some interesting points to be made.
First, the language used. Throughout all versions of the Oath there is use of the word 'art'. The various versions posted on Wikipedia (original, classic and modern) all contain 'art' and implicitly imply that medicine, whilst being science is also part art. I have to say that against all my scientific training and background, I do kinda like this. I like it because it suggests that science can take Medicine so far, but art perhaps takes it that little bit further. Importantly, it puts physicians in the driving seat when it comes to the care they provide for individuals perhaps differing from person to person. This article says pretty much the same. Remember also my post on autism and n=1?
Second, the Oath acknowledges that physicians, whilst respected for their science and their art, are not infallible. To quote from the modern text: "I will not be ashamed to say that I know not..". I think it is a mark of great strength when someone can admit that they don't know something and ask advice from those who might. This part of the Oath directs physicians to do just that.
Third, the Oath talks about treating 'people' not diseases or conditions. In these modern times, where finances for healthcare are being squeezed and contact time with patients is an issue to meet targets (certainly here in the UK), it is perhaps important to step back and understand that the patient is key, not the condition, disease, injury or state. The implication for autism for example is that 'underneath' the presentation of symptoms is a person (and their family, as also discussed in the Oath) and that the duty of care is to that person, whatever care they may or may not require either as a result of their autism or resultant from any associated co-morbidity.
Finally, the modern Oath quotes: "Above all, I must not play at God". Medicine has seen a few examples of physicians trying to play God. Here in the UK we had Dr Harold Shipman not so long ago; lest we forget his victims that ran into the hundreds in numbers. Away from just mortality (which this sentence of the Oath is specifically focused on) the message here is that physicians have an extremely important responsibility over their patients and their care; a responsibility that resonates throughout the medical and peripheral professions.
Some final words from a protagonist in our friendly neighbour-hood Spiderman movie (or was it Chris Eubank): "With great power comes great responsibility".
Regression and autism: then and now
The words 'regression and autism' mean different things to different people. To some, regression relates to diagnosis and in particular that little-known diagnostic box, childhood disintegrative disorder or Heller syndrome. To some, regression is a debate of definition and characterisation in the course of autism symptoms. To some, regression relates to events and sudden loss of functions and onset of symptoms.
In this post I am specifically focusing on the definition and characterisation of 'regression' relating to autism, and in particular how views and opinions on regression might have changed over the years. I would stress that I am not talking about regression occurring as a consequence of an intervention or some other man-made change i.e. an adverse drug reaction or a change of school / environment; although I do realise how difficult it might be to separate out such factors from symptom course.
Looking into the early years of autism research, there were reports and reports which detailed regression-type presentation of autistic symptoms - that is, a loss of previously-acquired skills. Interestingly, many of these reports whilst mentioning regression, tended to characterise behavioural regression as being due to things like epilepsy / seizure-type disorders or diagnosed as Heller syndrome or in some cases 'blamed' on co-morbidity such as tuberous sclerosis. Puberty was also a potential explanator in later childhood (I will perhaps come back to this at a later date). I may be wrong but it seemed like autism was somehow not seen as being able to be a regressive condition in its earliest years.
Sometime during the early to mid-1990's a change seemed to be apparent. First, researchers started talking more about regression in autism. Papers such as this one by Fred Volkmar (1992) described how uneven patterns of symptoms and developmental regressions were actually quite prevalent in autism and, furthermore, seemingly more prevalent in the 'lower-functioning' ability range.
At about this time, Cathy Lord and colleagues also published their revisions to the ADI (the ADI-R) (1994). Those in the know will know that ADI-R includes items discussing the issue of regression - or more accurately 'loss of language/other skills'. I am not saying that this was a significant addition to the ADI-R, merely that one of the gold-standard assessment instruments now included 'regression' as part of its schedule.
The floodgates seemed to be opened after this point and regression was something that appeared in various papers, texts and books as being, quote: "a typical event in the natural course of autism". So where has the concept of regression in autism gone since?
Well first of all some authors have suggested that regression might be hard-wired as part of the symptom presentation of some people with autism - a sort of genetic predisposition to regressive presentation of some symptoms. The same authors do not rule out regression occurring as a result of environmental events as a 'second-hit'. Specific assessment tools have also been developed to more accurately quantify regression in autism; one example is the Regression Supplement Form - a sort of add-on for the ADI-R.
We don't have a precise figure on the percentage of autism cases associated with regression partly because regression is such a nebulous term covering all kinds of different regressive symptoms. Estimates of varying degrees of language regression in autism range from 15% in this study to 20% in this study. Regression in social interactive behaviours seems to be following suit in terms of percentages, bearing in mind that language and social behaviours seem to be linked.
Various other co-morbid conditions have also been tied into regression in autism. A family history of coeliac disease, inflammatory bowel conditions and rheumatoid arthritis were associated with language regression in this study - oh, also specific functional bowel symptoms too.
The debate has moved on from asking if regression is present in autism, to things like ascertaining sub-groups within the regression camp. I remember being very interested in seeing the work from Sally Ozonoff and colleagues on their description of the 'delays-plus-regression' phenotype for example.
A possible association between regression in autism and comorbid mitochondrial disease has been the source of quite a lot of speculation quite recently and perhaps represents regression in autism turning full circle and going back to 'caused by other things' (assuming that mitochondrial disorder is comorbid and not a 'cause' of autism). I can't really add too much more to this debate because I don't know enough about mitochondrial disorders aside from what I read in places like this.
So there you have it. Regression has come along way in autism over the past 20 years or so. Having said that, can anyone tell me if DSM or ICD criteria for autism mention regression, or propose to mention it in future editions?
In this post I am specifically focusing on the definition and characterisation of 'regression' relating to autism, and in particular how views and opinions on regression might have changed over the years. I would stress that I am not talking about regression occurring as a consequence of an intervention or some other man-made change i.e. an adverse drug reaction or a change of school / environment; although I do realise how difficult it might be to separate out such factors from symptom course.
Looking into the early years of autism research, there were reports and reports which detailed regression-type presentation of autistic symptoms - that is, a loss of previously-acquired skills. Interestingly, many of these reports whilst mentioning regression, tended to characterise behavioural regression as being due to things like epilepsy / seizure-type disorders or diagnosed as Heller syndrome or in some cases 'blamed' on co-morbidity such as tuberous sclerosis. Puberty was also a potential explanator in later childhood (I will perhaps come back to this at a later date). I may be wrong but it seemed like autism was somehow not seen as being able to be a regressive condition in its earliest years.
Sometime during the early to mid-1990's a change seemed to be apparent. First, researchers started talking more about regression in autism. Papers such as this one by Fred Volkmar (1992) described how uneven patterns of symptoms and developmental regressions were actually quite prevalent in autism and, furthermore, seemingly more prevalent in the 'lower-functioning' ability range.
At about this time, Cathy Lord and colleagues also published their revisions to the ADI (the ADI-R) (1994). Those in the know will know that ADI-R includes items discussing the issue of regression - or more accurately 'loss of language/other skills'. I am not saying that this was a significant addition to the ADI-R, merely that one of the gold-standard assessment instruments now included 'regression' as part of its schedule.
The floodgates seemed to be opened after this point and regression was something that appeared in various papers, texts and books as being, quote: "a typical event in the natural course of autism". So where has the concept of regression in autism gone since?
Well first of all some authors have suggested that regression might be hard-wired as part of the symptom presentation of some people with autism - a sort of genetic predisposition to regressive presentation of some symptoms. The same authors do not rule out regression occurring as a result of environmental events as a 'second-hit'. Specific assessment tools have also been developed to more accurately quantify regression in autism; one example is the Regression Supplement Form - a sort of add-on for the ADI-R.
We don't have a precise figure on the percentage of autism cases associated with regression partly because regression is such a nebulous term covering all kinds of different regressive symptoms. Estimates of varying degrees of language regression in autism range from 15% in this study to 20% in this study. Regression in social interactive behaviours seems to be following suit in terms of percentages, bearing in mind that language and social behaviours seem to be linked.
Various other co-morbid conditions have also been tied into regression in autism. A family history of coeliac disease, inflammatory bowel conditions and rheumatoid arthritis were associated with language regression in this study - oh, also specific functional bowel symptoms too.
The debate has moved on from asking if regression is present in autism, to things like ascertaining sub-groups within the regression camp. I remember being very interested in seeing the work from Sally Ozonoff and colleagues on their description of the 'delays-plus-regression' phenotype for example.
A possible association between regression in autism and comorbid mitochondrial disease has been the source of quite a lot of speculation quite recently and perhaps represents regression in autism turning full circle and going back to 'caused by other things' (assuming that mitochondrial disorder is comorbid and not a 'cause' of autism). I can't really add too much more to this debate because I don't know enough about mitochondrial disorders aside from what I read in places like this.
So there you have it. Regression has come along way in autism over the past 20 years or so. Having said that, can anyone tell me if DSM or ICD criteria for autism mention regression, or propose to mention it in future editions?
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