Coeliac disease, autism and more

"Compared with the general population, children with celiac disease had a 1.4-fold greater risk of future psychiatric disorders. Childhood celiac disease was identified as a risk factor for mood disorders, anxiety disorders, eating disorders, behavioral disorders, ADHD [attention-deficit hyperactivity disorder], ASD [autism spectrum disorder], and intellectual disability."

So said the study findings reported by Agnieszka Butwicka and colleagues [1] who, yet again, relied on one of those oh so important Scandinavian nationwide [research] registries to look at potential extra-intestinal comorbidity associated with a diagnosis of coeliac (celiac) disease. This research group have been pretty active in 'mining' the Swedish population databases in relation to various aspects potentially linked to labels like autism (see here and see here for examples). Importantly, at least one of the authors has also talked about how any connection specifically between coeliac disease (CD) and autism is likely to be rather complicated (see here).

OK, back one step. Coeliac disease (CD) is the premier autoimmune condition - that's autoimmune condition not allergy - where dietary gluten is the [mostly modifiable] baddie. There is a growing realisation in the peer-reviewed science community that aside from the gastrointestinal (GI) manifestations of CD, it looks like extra-intestinal 'effects' are not uncommon too (see here for example) including those affecting early years development (see here). Of the myriad of other diagnoses/labels that have been mentioned alongside CD down the years, autism or ASD has cropped up more than once; leading some to suggest that there may be a connection between the two diagnoses and onward, the need for additional screening (see here). I might add that the gluten connection to CD also overlaps with 'some' research hinting that dietary gluten might have 'effects' for some on the autism spectrum too (see here).

The current Butwicka results represent something quite important. No, they do not infer that everyone diagnosed with autism or ADHD or mood disorder or anxiety disorder has CD but rather that these labels are not protective against the development of CD. Indeed, something else important is mentioned by the authors: "In contrast, siblings of celiac disease probands were at no increased risk of any of the investigated psychiatric disorders." This implies that the relationship, in general terms, seems to be quite specific to the biology / genetics and clinical course of CD and those other developmental/behavioural/psychiatric labels.

Then a tantalising question: what happens to these extra-intestinal labels/conditions when CD is managed/treated via a gluten-free diet? Well, we'll have to wait and see for the science to catch-up but I daresay for some, treating CD might be an important step to managing other labels too (see here)...

Music to close: and double-denim never really went out of fashion y'know...

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[1] Butwicka A. et al. Celiac Disease Is Associated with Childhood Psychiatric Disorders: A Population-Based Study. J Pediatr. 2017 Mar 7. pii: S0022-3476(17)30153-1.

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Butwicka A, Lichtenstein P, Frisén L, Almqvist C, Larsson H, & Ludvigsson JF (2017). Celiac Disease Is Associated with Childhood Psychiatric Disorders: A Population-Based Study. The Journal of pediatrics PMID: 28283256

[Objective] exposure to flame retardants and social behaviours

Although a few details of the study reported by Shannon Lipscomb and colleagues [1] (open-access) interested me, I was particularly taken by their use of "a silicone passive wristband sampler [worn] around his/her wrist or ankle" to "assess the child’s exposure to flame retardants" as part of their investigation "to determine if flame retardant exposure was associated with measurable differences in social behaviors among children ages 3–5 years."

I've covered the topic of potential adverse effects associated with exposure to flame retardants such as brominated diphenyl ethers (BDE) before on this blog (see here and see here for examples). Such compounds are listed as POPs (persistent organic pollutants) because of their ability to endure in the environment, accumulate in the body and potentially [adversely] affect various biological systems. In other words, these are compounds that might well have served an important purpose at one time - flame retardants - but are now realised to have quite a risk profile attached to them. Sounds familiar doesn't it?

Anyhow, Lipscomb et al relied on other research [2] suggesting that various compounds/chemicals can be sequestered from silicone wristbands - those plastic things that many people wear for various causes - with the right equipment and under the right circumstances. To any analytical chemist, this is probably scientific music to their ears. They "extracted and analyzed for 41 different flame retardant compounds using gas chromatography mass spectrophotometry" and focused on 11 compounds "PBDE-47, PBDE-99, PBDE-153, PBDE-154, PBDE-49, PBDE28 + 33, tris(1,3-dichloro-2-propyl) phosphate], TPP [e.g. triphenylphosphate], TCPP [e.g tris(1-chloro-2-propyl) phosphate], and TCEP [e.g. tris(2-chloroethyl) phosphate" that were quite readily present in 60% or more of wristbands. For some of the compounds the authors generated a 'sum of' score; for example: "ƩPBDEs is the total amount of PBDE-47, PBDE-99, PBDE-153, PBDE-154, PBDE-49, and PBDE28." Social behaviours by the way, were scored by teachers in the preschool setting of participants using the Social Skills Improvement System - Rating Scales.

Results: 92 children were initially recruited onto the study but only 77 children returned their wristbands intact (i.e. some of them 'went through the laundry'). Further: "a final sample size of 69 children with complete data... were included in the final analyses." Then: "Bivariate analysis revealed modest correlations between flame retardant exposure and some of the social behavior subscales." What this suggests is that there may be some evidence that such compounds (including organophosphate-based flame retardants (OPFRs)) might impact on aspects of social skills development but there are constraints based on the sample size used and the reliance on one primary measure of social skills for examples.

As per the previous sentence, I'm not totally convinced by this data but am still really interested in the use of wristband samplers described by Lipscomb and colleagues. I can see how this kind of objective measure of exposure could really add another dimension to lots of different areas of research on environmental exposures in relation to various labels. Take for example the quite complicated area of research talking about maternal air pollution exposure and offspring autism risk (see here). Instead of just relying on postcode (zip code) in relation to mapping (estimating) pollution exposure, one could potentially adapt the chemical assay to screen for particulate matter for example, as collected on those wristbands. Certainly an easier way than lugging around a portable air monitor I would have thought. No doubt there are also other uses for such simple solutions...

Music: Europe - The Final Countdown. 80s rock hairstyles at their best and perhaps an apt song given what happened here in Blighty yesterday...

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[1] Lipscomb ST. et al. Cross-sectional study of social behaviors in preschool children and exposure to flame retardants. Environmental Health 2017; 16: 23.

[2] O'Connell SG. et al. Silicone Wristbands as Personal Passive Samplers. Environ. Sci. Technol. 2014; 48: 3327–3335.

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Lipscomb ST, McClelland MM, MacDonald M, Cardenas A, Anderson KA, & Kile ML (2017). Cross-sectional study of social behaviors in preschool children and exposure to flame retardants. Environmental health : a global access science source, 16 (1) PMID: 28274271

L-methylfolate administration and autism: a case report

I should have really titled this post 'another case report' given yesterday's entry on this blog talking about a case of [untreated] PKU and autistic behaviours/diagnosis. Here I am again talking about another N=1 with autism in mind and specifically the findings reported by Kim Siscoe & David Lohr [1] on how: "L-methylfolate supplementation improved symptoms of aggression and disruptive behavior in a child with autism who tested positive for the C677TT allele of the methyltetrahydrofolate reductase enzyme gene."

First things first. This was a case report; please keep that in mind. Second, I am not a medical doctor and don't provide medical or clinical advice on this blog. Within those caveats I am however very interested in the Siscoe/Lohr observations.

Why? Well, methylene tetrahydrofolate reductase (MTHFR) (gene and enzyme) has featured quite a bit on this blog in light of findings linking gene and enzyme to cases of autism (see here and see here for examples). The idea is that MTHFR serves a primary function in reducing the compound 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate. 5-methyltetrahydrofolate - another name for L-methylfolate -  the reduced and methylated form of folic acid, is an important methyl group donor for the recycling of homocysteine back to methionine utilising vitamin B12 along the way (see here for a nice hand drawn graphic). The implications of disruptions to MTHFR (gene and enzyme) are potentially multiple but include effects on methyl group donor ability (methyl groups potentially linked to things like DNA methylation as part of all that epigenetics jazz that you hear so much about these days) and effects on downstream metabolites such as those related to homocysteine metabolism (see here).

So Siscoe & Lohr present data on what happened when the active form of folate was supplemented following the identified genetic issue with the MTHFR gene potentially affecting typical production of L-methlyfolate.

Where next with this work? Well, it stands to reason that in these days of personalised medicine percolating through to autism research and practice (see here), knowledge about a potential genetic issue identified in [some] cases of autism should be further investigated. We have other examples (see here). I'd like to see larger and more controlled trials of L-methlyfolate supplementation in relation to autism for example, based on screening for issues with the MTHFR gene. I'd like to see a few more biological measures incorporated in such study looking at other aspects of the folate and related cycles too (see here). I'd also like to see more discussion about any long-term implications and/or adverse effects associated with such supplementation along the lines of: should we really be tinkering with mechanisms linked to DNA methylation? Also in relation to some of the other diagnoses associated with issues with MTHFR there is similarly important work emerging [2] which could be quite important in certain instances...

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[1] Siscoe KS. & Lohr WD. L-Methylfolate supplementation in a child with autism and methyltetrahydrofolate reductase, enzyme gene C677TT allele. Psychiatr Genet. 2017 Mar 7.

[2] Roffman JL. et al. Biochemical, physiological and clinical effects of l-methylfolate in schizophrenia: a randomized controlled trial. Mol Psychiatr. 2017. Mar 14.

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Siscoe, K., & Lohr, W. (2017). L-Methylfolate supplementation in a child with autism and methyltetrahydrofolate reductase, enzyme gene C677TT allele Psychiatric Genetics DOI: 10.1097/YPG.0000000000000170

Presenting with the symptoms of autism and then diagnosed with phenylketonuria (PKU)

The case report from Betül Mazlum and colleagues [1] (open-access available here) illustrates once again that (a) the plural 'autisms' exist (see here) and (b) screening for inborn errors of metabolism (IEM) should be an important part of any autism assessment (see here). Indeed, screening for IEM should really be part of assessments for many different labels...

Detailing a case report wherein a 3-year old child came to clinical attention for "speech delay and social problems", the authors describe how following a diagnosis of "autism according to DSM-IV criteria" further investigations were undertaken. Said investigations included analysis of blood and urine amino acid levels and, voilà, high levels of phenylalanine were detected and a diagnosis of phenylketonuria (PKU) made. Initiation of a low phenylalanine diet (the treatment of choice for PKU) followed and was accompanied by some important [positive] changes to behaviour and cognition. Of particular note to the presentation of autism we are told that: "At 4 months follow-up improvement was noticed in his eye contact, joined attention and speech."

The authors further note: "This case was not at particular risk for PKU at first thought, being born to non-consanguineous parents and during a period when newborn screening with Guthrie test was widely applied in Turkey. Although the child had a heel prick in the hospital where he was delivered, the results are unavailable and therefore whether his sample was analyzed is questionable."

OK, this was a case report and whilst an important 'N=1' is not necessarily generalisable to all autism (or rather all autisms). Insofar as the methods talked about for establishing raised phenylalanine - "Blood and urine amino acid chromatography" - I would have liked to have seen a little more detail in relation to the specific 'chromatography' methods used and any results related to another aromatic amino acid (tyrosine). We don't also have any data on follow-up either (repeat biological testing)...

PKU is an important but quite rare IEM. This is not however the first time that PKU has been linked to autism or the presentation of autistic traits (see here) particularly in cases of 'untreated' PKU. Aside from PKU providing quite a good template for how diet - certain aspects of diet - can affect behaviour and mental state for some (see here) there are other potential implications and 'correlations' on the back of this work. Not least is the intersection between another intervention measure potentially indicated for PKU - tetrahydrobiopterin (sapropterin or BH4) - and research suggesting that the 'mopping up phenylalanine' properties of this compound might be potentially effective for some cases and facets of autism too (see here) based on double-blind, placebo-controlled trial results [2].

"The possibility of a metabolic disorder including PKU should be considered in any child presenting with symptoms of autism, learning or speech problems and PKU should be tested unless the newborn screening results are available." I wouldn't argue with those sentiments [3], allowing for the fact that other correlates should also be considered (see here for example) particularly it seems, when autism appears alongside something like intellectual (learning) disability. The question of whether the quite restrictive low phenylalanine diet typically indicated for PKU might also impact autistic signs and symptoms is something that science still perhaps needs to look into...

Music to close, and how about something lively from The King?

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[1] Mazlum B. et al. A late-diagnosed phenylketonuria case presenting with autism spectrum disorder in early childhood. Turk J Pediatr. 2016;58(3):318-322.

[2] Klaiman C. et al. Tetrahydrobiopterin as a treatment for autism spectrum disorders: a double-blind, placebo-controlled trial. J Child Adolesc Psychopharmacol. 2013 Jun;23(5):320-8.

[3] Bilder DA. et al. Neuropsychiatric comorbidities in adults with phenylketonuria: A retrospective cohort study. Mol Genet Metab. 2017 Mar 6. pii: S1096-7192(17)30052-5.

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Mazlum B, Anlar B, Kalkanoğlu-Sivri HS, Karlı-Oğuz K, Özusta Ş, & Ünal F (2016). A late-diagnosed phenylketonuria case presenting with autism spectrum disorder in early childhood. The Turkish journal of pediatrics, 58 (3), 318-322 PMID: 28266201

Detecting stereotypic behaviours through technology

"We have designed an Internet-of-Things (IoT) framework named WearSense that leverages the sensing capabilities of modern smartwatches to detect stereotypic behaviors in children with autism."

So said the paper by Amir Mohammad Amiri and colleagues [1] (open-access available here) and, I have to say, something that really piqued my [research] attention. Describing how authors managed to design and construct a smartwatch with the ability to "detect three behaviors, including hand flapping, painting, and sibbing [hitting themselves on the top of their head] that are commonly observed in children with autism" they report some preliminary findings.

When I say these are preliminary findings, I do indeed mean preliminary, as a two-phase preliminary trial included data from "12 healthy subjects aged between 23–33" and "two subjects (ages 15 and 16) diagnosed with autism." Aside from the implication that young adults with autism are somehow 'not healthy' (I think the correct terminology should be 'not diagnosed with autism/autism spectrum disorder'), you can perhaps see that much of the data for this study came from artificial, induced behaviours not necessarily produced by those on the spectrum - "The tasks that the subjects were invited to do included three different types for 20 s." I do have some other quibbles about the write-up of this study as per very generalised sentences like: "These stereotypic behaviors happen when a child is trying to regulate the sensory input from their surrounding environment."

But I don't want to take anything away from the potential of this kind of research and where, with a bit more study and refinement, it could take many areas of autism research and practice. Accepting the argument that stereotypic behaviours that can accompany autism are not always something that needs to be tinkered with, I can perhaps see a use for this technology when it comes to screening and assessment. If for example, this kind of technology could be applied to something like an ADOS assessment, you could perhaps see how there may be additional information to be garnered (and indeed, built up coincidental to the 'objectivity' linked to such an exam). Coupled with other technology in relation to things like gaze monitoring for example, the potential gets even more exciting. And then also are the potentials of this kind of tracking software in relation to monitoring physical activity and autism (see here for example) or even in the context of epilepsy occurring alongside autism (see here for another WearSense use). There may be lots more to see when it comes to such technology and autism...

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[1] Amiri AM. et al. WearSense: Detecting Autism Stereotypic Behaviors through Smartwatches. Healthcare (Basel). 2017 Feb 28;5(1).

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Amiri AM, Peltier N, Goldberg C, Sun Y, Nathan A, Hiremath SV, & Mankodiya K (2017). WearSense: Detecting Autism Stereotypic Behaviors through Smartwatches. Healthcare (Basel, Switzerland), 5 (1) PMID: 28264474

Including the "full intellectual range" in autism vision research

The paper by Alyse Brown and colleagues [1] (open-access available here) is probably not going to gain any significant media headlines (unlike other recent studies - see here and see here) but does cover a rather important question regarding the autism research landscape: how representative is autism research?

Specifically looking at the collected research on visual processing (distinct from physical issues with the eyes that still require greater awareness) with autism in mind, the authors surveyed the research literature to determine "what extent the ASD with-ID [intellectual disability] population has been excluded from visual research." Intellectual or learning disability is one of the more frequently over-represented comorbidities that can accompany a diagnosis of autism or autism spectrum disorder (ASD). Their answer: "our searches indicate that 80% of the vision research associated with ASD is representative of less than 60% of the appropriate population, i.e., those with ASD without ID while the ASD with ID group who we argue currently represent 42% of the ASD population, have not been adequately considered."

You may well quibble with the "recalculation of ASD prevalence figures, using the criteria of DSM-5" as a means of calculating that '~40% of those with autism have ID too' figure. For me however, the message is quite stark: autism research - specifically related to visual processing issues - is not yet representative of  'all autism'.

"Reluctance to test individuals who are below 80 in IQ is presumably a practical stance as the data collected from these individuals are often hard to obtain, and often close to floor level performance." The authors note however that the presence of ID alongside autism in the area of visual processing is not something that cannot be 'overcome' by researchers with some creative thinking and a few modification(s) to their experimental designs. Indeed, visual processing research lends itself well to quite a few alterations to methods [2]...

How applicable might these results be to other areas of autism research? Well, we just don't know. I daresay that quite a lot of the 'psychology' based autism research in particular might show a bias towards autism without intellectual disability for just those reasons listed above. The problem then of grand, over-arching generalisations to 'all autism' on the basis of results from the more 'cognitively-able' becomes apparent. Of course, in these days of the plural 'autisms' (see here) and the realisation that 'heterogeneity means heterogeneity' when it comes to autism (see here) one could argue that even characterisations based on the presence of ID or not when it comes to autism are equally 'simplistic' and equally 'useless'. How many autisms might well have an ID element to them? Is ID a comorbidity or something rather more central to some of the autisms? These questions and related others are ones that autism research as a whole will eventually have to start looking at and taking into account.

And going back to the issue of eye disorders being potentially over-represented and under-diagnosed in relation to autism, the paper by Mouridsen and colleagues [3] reiterates that intellectual ability when accompanying autism needs more health equality: "The rate of eye disorder was particularly high (24.5%) in those with a co-occurring profound or severe learning disability (IQ < 50)."

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[1] Brown AC. et al. Vision Research Literature May Not Represent the Full Intellectual Range of Autism Spectrum Disorder. Front Hum Neurosci. 2017 Feb 14;11:57.

[2] Boot FH. et al. Delayed visual orienting responses in children with developmental and/or intellectual disabilities. J Intellect Disabil Res. 2013 Dec;57(12):1093-103.

[3] Mouridsen SE. et al. Eye Disorders among Adult People Diagnosed with Infantile Autism in Childhood: A Longitudinal Case Control Study. Ophthalmic Epidemiol. 2017 Mar 15:1-4.

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Brown AC, Chouinard PA, & Crewther SG (2017). Vision Research Literature May Not Represent the Full Intellectual Range of Autism Spectrum Disorder. Frontiers in human neuroscience, 11 PMID: 28261072

Autism and anxiety disorder: zooming in on the details

Although it is not necessarily new news that (a) autism rarely exists in some sort of diagnostic vacuum, and (b) that some of the comorbidity 'over-represented' when it comes to autism can actually be more disabling than autism itself, there are still more investigations to be done.

The paper by Vicki Bitsika & Christopher Sharpley [1] represents an example of how autism science is starting to go past the whole 'is there a connection between...' bit when it comes to autism and various comorbidity, specifically focused on the issue of anxiety. Looking at parental responses on "the Social Responsiveness Scale (SRS) and the GAD subscale of the Child and Adolescent Symptom Inventory (CASI-4 GAD) about their sons" researchers reported some rather interesting trends when it came to the two based on a cohort of young males diagnosed with autism. The authors used the term 'high-functioning' to describe the particular 'type' of autism being looked at in their study but I'm rather less sure this is an appropriate description ('high- and low-functioning' tend to be very generalised terms).

I should back-track slightly and point out that the reasoning behind this research was to "assist in treatment or avoidance of GAD [generalised anxiety disorder] by identifying ASD [autism spectrum disorder]-related behaviours as 'targets' for intervention with anxious children as well as for preventative treatments that could be implemented into daily routines before children become anxious." Of all the debates past and present in relation to autism, specifically on the topic of 'treatment' (or even 'cure'), I don't think anyone would be opposed to the idea that anxiety (whether symptoms or disorder) should be treated and potentially 'cured' in this context. Anxiety can be absolutely disabling including when tied into autism.

Results: bearing in mind their focus on only two parameters (SRS scores and GAD scores) in this study, there are some interesting trends in need of further investigation. So: "For pre-adolescents, high levels of tension in social situations were associated with 3.5-times greater likelihood of having GAD; for adolescents, experiencing difficulty in changes in routine was associated with a 10-fold increase in risk of GAD." The pre-adolescents and adolescents bit in that sentence was due to the division of their cohort on the basis of age. The results suggest therefore that anxiety (or at least GAD) might express itself for various different reasons potentially linked to the age/maturity of the person.

I know some people might be shrugging their shoulders at such a finding and saying 'we already knew that'. Well, I'm not one of them. Take for example the 'change in routines' as being a possible factor in the expression of GAD in adolescents. The recent work by Joyce and colleagues [2] looking at another important term relevant to this issue - intolerance of uncertainty - adds an additional layer to the Bitsika/Sharpley findings as per their conclusion that: "replicated previous findings based on parent report showing a significant positive relationship between RRB [restricted and repetitive behaviours] and anxiety." RRBs can, amongst other things, include responses to routine (and changes to said routines).

As to the question of what such findings might mean in the context of intervention, the authors talk about how intervening in the symptoms of GAD (a kind of reactionary approach) might also benefit from also trying to focus intervention on certain autistic symptoms too. Outside of the [careful] use of some of the talking/behavioural therapies and perhaps the whiff of some effect from certain pharmacological interventions when it comes to RRBs and autism, there isn't a great deal on offer at the moment in autism science and practice in this area. Indeed, if the relationship between RRBs and anxiety is further confirmed (and I mean confirmed [3]), I'd perhaps suggest that moves to target RRBs in the context of autism could/should be a research priority if only to potentially reduce the effects of anxiety.

And the inquiry continues [4]...

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[1] Bitsika V. & Sharpley CF. The association between parents' ratings of ASD symptoms and anxiety in a sample of high-functioning boys and adolescents with Autism Spectrum Disorder. Res Dev Disabil. 2017 Mar 1;63:38-45.

[2] Joyce C. et al. Anxiety, Intolerance of Uncertainty and Restricted and Repetitive Behaviour: Insights Directly from Young People with ASD. J Autism Dev Disord. 2017 Feb 25.

[3] Wang S. et al. Sex Differences in Diagnosis and Clinical Phenotypes of Chinese Children with Autism Spectrum Disorder. Neurosci Bull. 2017 Feb 25.

[4] South M. et al. Symptom overlap on the srs-2 adult self-report between adults with asd and adults with high anxiety. Autism Res. 2017. March 7.

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Bitsika, V., & Sharpley, C. (2017). The association between parents’ ratings of ASD symptoms and anxiety in a sample of high-functioning boys and adolescents with Autism Spectrum Disorder Research in Developmental Disabilities, 63, 38-45 DOI: 10.1016/j.ridd.2017.02.010

Congenital cytomegalovirus (CMV) infection and autism continued

I wanted to briefly talk about the paper by Francesca Garofoli and colleagues [1] on congenital cytomegalovirus (CMV) infection and autism not because it contains any novel data (see here), but because it reminds us that the potential 'pathways' to a diagnosis of autism are multiple and not necessarily 'pre-programmed' as per the 'it's all genetic' arguments that frequently figure in various domains.

Congenital CMV infection refers to the transmission of CMV - "a common virus that belongs to the herpes family of viruses" - from mother to foetus during pregnancy. The details are still under investigation as to how and why CMV affects a foetus (bearing in mind this is quite a common virus) but autism as a consequence of [some] congenital CMV infection has growing evidence-based support [2].

Garofoli et al included 70 'proven' cases of CMV "congenitally-infected infants" in their study; specifically looking "to correlate congenital cytomegalovirus (CMV) infection with autism spectrum disorder (ASD) and to define its prevalence." They determined that 2 of their 70 strong cohort met criteria for an ASD at the age of 3 years. Two of 70 translated as 2.8% of their cohort and contrasts with [estimated] autism prevalence "in general Italian population (0.66-1.36%)." The figure of 2.8% is also not a million miles away from other estimates of autism suggested via congenital CMV infection [3].

Although 2.8% of the cohort (2/70) might not sound like a lot I'm inclined to suggest that it does prompt quite a lot more additional investigation. Not least is the question: 'why was autism/ASD not diagnosed in the other 68 children?' and onward whether other factors (genetics(!), biology, infection timing, immunologic response, etc) might come into play [4] in relation to the congenital CMV infection - autism association? Taking also into account the estimated prevalence of ASD in Italy, these figures (estimates) do seem to be a little lower than that described in other geographical locations (see here and see here for examples). Indeed, bearing in mind the research evidence already looking at estimated ASD prevalence in Italy [5] it's not unfair to say that 'under-estimation' might be a familiar theme...

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[1] Garofoli F. et al. An Italian Prospective Experience on the Association Between Congenital Cytomegalovirus Infection and Autistic Spectrum Disorder. J Autism Dev Disord. 2017 Mar 3.

[2] Ornoy A. et al. Prenatal factors associated with autism spectrum disorder (ASD). Reprod Toxicol. 2015 Aug 15;56:155-69.

[3] Engman ML. et al. Prenatal acquired cytomegalovirus infection should be considered in children with autism. Acta Paediatr. 2015 Aug;104(8):792-5.

[4] Lombardo MV. et al. Maternal immune activation dysregulation of the fetal brain transcriptome and relevance to the pathophysiology of autism spectrum disorder. Mol. Psychiatr. 2017. March 21.

[5] Ferrante M. et al. Prevalence and age at diagnosis of Autism Spectrum Disorder in south Italy, 2004–2014. Eur J Public Health. 2015; 25 (suppl_3).

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Garofoli F, Lombardi G, Orcesi S, Pisoni C, Mazzucchelli I, Angelini M, Balottin U, & Stronati M (2017). An Italian Prospective Experience on the Association Between Congenital Cytomegalovirus Infection and Autistic Spectrum Disorder. Journal of autism and developmental disorders PMID: 28258350

On genotype and environmental exposure patterns

I was rather interested to read the paper by Michela Traglia and colleagues [1] (open-access available here) concluding that: "maternal and fetal genetic make-up are important determinants of mid-gestational maternal circulating levels of some environmental organohalogens." Interested because, in these days of gene-environment interactions being applied to just about everything, the detail that is missing - which genes might potentially be linked to which environmental factors - has not yet been suitably addressed in the peer-reviewed science literature.

So, based on data - "serum levels of a set of 21 organohalogens in a subset of 790 genotyped women and 764 children" - derived from participants included in the Early Markers for Autism (EMA) Project, researchers set about assessing how genetics might impact on environmental pollutant exposure profiles. Maternal blood samples were collected at around 15-20 weeks pregnancy. Children provided blood samples via the fabulous resource that is the newborn screening program, where: "Newborn blood spots were collected on filter paper 1-2 days after birth." Maternal samples were analysed for various environmental pollutants and both sets of samples were analysed for the genetic material they contained pertinent to whether "circulating mid-gestational levels of organohalogens would be driven by common maternal genetic determinants, and that these results could shed light on the observed associations between the organohalogens and ASD [autism spectrum disorder]."

Results: yes, the authors "found evidence that a large proportion of maternal circulating levels of BB-153, BDE-47, -100, -153 [polybrominated congeners] and their sum was significantly controlled by common genetic factors." Those 'common genetic factors' typically referred to the presence of point mutations (SNPs) that litter everyone's genome and on occasion, can affect the function/production of specific biological processes. So: "Genome-wide association analyses identified significant maternal loci for p,p'-DDE... in the CYP2B6 gene and for BDE-28... near the SH3GL2 gene, both involved in xenobiotic and lipid metabolism." In other words, although the environmental pollutants measured are not great products in the first place (in terms of safety), a person's genetic make-up can influence how such products are eventually dealt with by the body and potentially onwards, what subsequent effects they might have.

Additionally: "results suggest that the maternal circulating levels of some compounds were more highly influenced by fetal genetic factors than maternal genetics." This leads into another aspect of the current study whereby foetal genetic factors might also play a part in "controlling the toxicant disposition between mother and fetus." Specifically, authors noted that aspects of the individual genetics of a foetus (distinct from its mother) "contributed to the levels of BDE-100... and PCB187... near the potential metabolic genes LOXHD1 and PTPRD, previously implicated in neurodevelopment."

And finally: "We confirmed that the serum levels of BDE-100, -153 and the total sum of PBDEs were significantly lower in mothers of ASD-affected children compared to mothers of control children." This is interesting in light of other discussions about PBDEs and autism in particular (see here). The authors do discuss various scenarios to account for their results not least that "transplacental transfer of organohalogens during pregnancy may be driven by the fetal genome expressed in placenta." Further analyses of the 'placentome' might therefore be indicated.

To reiterate, this is interesting research. It tells us that many [adverse] environmental exposures, whilst typically to be avoided, don't act on the body in a uniform way as a function of differing genomes and differences in the ways that the body 'handles' such exposures. With autism in mind, this is not necessarily new news (remember paraoxonase gene variants and organophosphate metabolism [2] and air pollution and offspring autism?) but is a useful reminder. Such work also provides a template for looking at the myriad of other environmental factors put forward to influence autism risk and whether individual product safety is necessarily the only or most important factor when it comes to assessing relative risk profiles.

I might finally also draw your attention to a recent interesting meta-analysis of the various environmental risk factors potentially linked to autism [3] (open-access) and another article talking about similar things [4] (open-access) (thanks Annabelle). Genes and environment, genes and environment...

Music: Petula Clark sings the Beatles? Personally, I think it's better than the original...

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[1] Traglia M. et al. Independent Maternal and Fetal Genetic Effects on Mid-gestational Circulating Levels of Environmental Pollutants. G3 (Bethesda). 2017 Feb 24. pii: g3.117.039784.

[2] D'Amelio M. et al. Paraoxonase gene variants are associated with autism in North America, but not in Italy: possible regional specificity in gene-environment interactions. Mol Psychiatry. 2005 Nov;10(11):1006-16.

[3] Modabbernia A. et al. Environmental risk factors for autism: an evidence-based review of systematic reviews and meta-analyses. Molecular Autism. 2017; 8: 13.

[4] Parker W. et al. The role of oxidative stress, inflammation and acetaminophen exposure from birth to early childhood in the induction of autism. Journal of International Medical Research. 2017. Jan 20.

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Traglia M, Croen LA, Lyall K, Windham GC, Kharrazi M, DeLorenze GN, Torres AR, & Weiss LA (2017). Independent Maternal and Fetal Genetic Effects on Mid-gestational Circulating Levels of Environmental Pollutants. G3 (Bethesda, Md.) PMID: 28235828

PACE trial recovery data and chronic fatigue syndrome - a reply

I'd encourage readers interested in the background to the response paper by Michael Sharpe and colleagues [1] to have a look at a previous blogging occasion when the topic of the PACE trial, chronic fatigue syndrome (CFS) and 'recovery' were discussed (see here).

Suffice to say that this latest paper is a reply to one published by Carolyn Wilshire and colleagues [2] who concluded that: "The claim that patients [with CFS] can recover as a result of CBT [cognitive behaviour therapy] and GET [graded exercise therapy] is not justified by the data, and is highly misleading to clinicians and patients considering these treatments." Said discussions linking back to some quite extensive debates on how one should (and shouldn't) treat/manage conditions like CFS (see here).

I wanted to highlight the latest Sharpe paper because (a) I anticipated a reply from these authors following the Wilshire paper criticism of their recovery paper [3], and (b) although the debates in this area have been quite extensive already, the use of the scientific peer-reviewed medium to discuss and even argue is an important avenue. The authors have a right to scientific reply.

So how did Sharpe et al respond? Well the words 'recovery', 'threshold' and ''no generally agreed measure of recovery" when it comes to CFS form the crux of the response to the Wilshire paper. They address the issue of recovery thresholds that have been a real source of discussion in relation to the PACE trial secondary analysis concluding that: "No participant met our full criteria for recovery at baseline." They point out that whilst "13% of participants met the recovery criterion of being within the normal range... for physical functioning when entering the trial" physical functioning was but one measure they used to determine recovery.

They also approach the topic of 'changing thresholds' when it came to the definition of recovery in the PACE trial. To quote: "We changed these thresholds for our detailed analysis plan because after careful consideration and consultation, we concluded that they were simply too stringent to capture clinically meaningful recovery." They also report that elements of their assessment - the PACE walking test - are "not comparable with data collected in other studies" as a function of their reliance on personal motivation/ability over and above the use of encouragement as in other studies.

Finally, authors also talk about 'what other studies have found regarding recovery' when it comes to CFS. They note that their findings in relation to the use of standard medical care (SMC) for CFS in the PACE trial were similar to other reports [4]. They also point to research suggesting that the use of CBT in independent study for CFS show similar rates of recovery [5] to theirs originally reported. In other words, they make a case for their findings fitting in with some of the other literature on this topic.

A quick trawl of PubMed with the terms 'chronic fatigue syndrome' and 'recovery' reveals that there is indeed quite a bit more to do in this area of science. To quote from one paper (a critical review) [4]: "Estimates of recovery ranged from 0 to 66 % in intervention studies and 2.6 to 62 % in naturalistic studies." What this tells us is that (a) how recovery is reported in relation to CFS is still in need of some clarification [6] and perhaps more importantly, agreed uniformity is still required in its assessment; (b) some of the measures used to form judgements of recovery when it comes to CFS are not necessarily fit for purpose [7] (bearing in mind not everyone agrees with this); and (c) further efforts need to go into looking at many more aspects of CFS recovery outside of just a reliance on the fatigue parameter (see here and see here for examples). In short, science does not really know what recovery looks like in relation to CFS [8] despite it seemingly happening for all manner of reasons...

Where do we go from here? This is a difficult question to answer. It is doubtful that the response from Sharpe and colleagues is going to change too many opinions about PACE given the strength of feeling on the topic and the various goings-on that have occurred around debate in this area (see here). Still today, other comments on the PACE trial continue to emerge in the peer-reviewed domain [9] from notable CFS researchers and there are even calls to retract the original recovery paper (see here). Yes, there are lessons to be learned from the PACE trial (e.g. stick to your "original protocol thresholds", make your data 'open-access' and think about how to do this in the planning/recruitment stages of your trial, be mindful that short-term gains don't necessarily translate into long-term ones, work with the ME/CFS community (rather than labelling elements of them 'vexatious' or worse when they ask questions or request data) but I can't see how these factors will immediately and positively affect the lives of people living with CFS/ME here and now. That recommendations on the use of CBT for CFS have already altered in some parts of the world (see here) - "The strength of evidence on global improvement is downgraded from moderate to low when considering CBT separately from other counseling and behavioral interventions" - and are potentially likely to change here in Blighty perhaps signifies that science and medicine is moving on when it comes to this topic. Science should be doubling its efforts to expand its research boundaries when it comes to managing CFS outside of just a reliance on the [outdated?] psychosomatic model and indeed, it is...

And on the topic of other CFS research avenues, I've already talked about a few interesting avenues on this blog (see here and see here and see here) mindful that when we talk about CFS/ME, we're probably not talking about just one entity (see here). Also alongside, that there seems to be an awful lot of 'over-represented' comorbidity accompanying quite a lot of CFS/ME (see here for example) to also contend with...

Music: Lush Life (even if you don't know the song title, you might recognise the tune).

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[1] Sharpe M. et al. Do more people recover from chronic fatigue syndrome with cognitive behaviour therapy or graded exercise therapy than with other treatments? Fatigue: Biomedicine, Health & Behavior. 2017. Feb 15.

[2] Wilshire C. et al. Can patients with chronic fatigue syndrome really recover after graded exercise or cognitive behavioural therapy? A critical commentary and preliminary re-analysis of the PACE trial. Fatigue: Biomedicine, Health & Behavior. 2016. Dec 14.

[3] White PD. et al. Recovery from chronic fatigue syndrome after treatments given in the PACE trial. Psychol Med. 2013 Oct;43(10):2227-35.

[4] Cairns R. & Hotopf M. A systematic review describing the prognosis of chronic fatigue syndrome. Occup Med (Lond). 2005 Jan;55(1):20-31.

[5] Flo E. & Chalder T. Prevalence and predictors of recovery from chronic fatigue syndrome in a routine clinical practice. Behav Res Ther. 2014 Dec;63:1-8.

[6] Twisk FN. A definition of recovery in myalgic encephalomyelitis and chronic fatigue syndrome should be based upon objective measures. Qual Life Res. 2014 Nov;23(9):2417-8.

[7] Matthees A. Assessment of recovery status in chronic fatigue syndrome using normative data. Qual Life Res. 2015 Apr;24(4):905-7.

[8] Brown B. et al. 'Betwixt and between'; liminality in recovery stories from people with myalgic encephalomyelitis (ME) or chronic fatigue syndrome (CFS). Sociol Health Illn. 2017 Feb 27.

[9] Jason LA. The PACE trial missteps on pacing and patient selection. Journal of Health Psychology. 2017. Feb 1.

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M Sharpe, T Chalder, AL Johnson, KA Goldsmith, & PD White (2017). Do more people recover from chronic fatigue syndrome with cognitive behaviour therapy or graded exercise therapy than with other treatments? Fatigue: Biomedicine, Health & Behavior, 1-5 : 10.1080/21641846.2017.1288629

ALSPAC says no to cat ownership - psychosis risk hypothesis but...

"While pregnant women should continue to avoid handling soiled cat litter, given possible T. gondii exposure, our study strongly indicates that cat ownership in pregnancy or early childhood does not confer an increased risk of later adolescent PEs [psychotic experiences]."

So said the findings reported by Francesca Solmi and colleagues [1] (open-access) who brought a smile to any reader of the title of their paper: "Curiosity killed the cat: no evidence of an association between cat ownership and psychotic symptoms at ages 13 and 18 years in a UK general population cohort." For those who might not be aware of the hypothesis, cat ownership has been previously linked to 'adverse' psychological outcomes (see here) tied into some peer-reviewed evidence on one possible environmental factor linked to psychosis and conditions manifesting psychosis: Toxoplasma gondii.

ALSPAC - Avon Longitudinal Study of Parents and Children - brought it's quite significant scientific prowess to bear on the question of whether "cat ownership in pregnancy and childhood (ages 4 and 10 years) was associated with psychotic experiences (PEs) in early (age 13, N = 6705) and late (age 18, N = 4676) adolescence, rated from semi-structured interviews." Having a cat in the house was not the only question asked by Solmi et al as the presence of other pets were also investigated: "dogs, rabbits, rodents, birds (all waves), and tortoises and fish (from 21 months)." PEs were assessed at approximate ages of 13 and 18 years old via responses to the "psychotic-like symptoms interview (PLIKSi), a semi-structured interviewer-rated screening assessment for PEs." Various other variables were also factored into the examination of any effect or not.

Results: well, as per the opening sentence to this post, cat ownership did not seem to be related to later PEs. The potential caveat being that in some of their analyses there did seem to be a possible association - "Owning a cat at age 4 years was associated with higher odds of having PEs at age 13 years in univariable models" - but the significance of this association disappeared when adjustments for other potentially confounding variables were made. Obviously this kind of study can't control for every single potentially confounding variable but they did at least try.

Why the disparity between these results and the previous ones suggestive of a possible connection between childhood cat ownership and later adverse psychological health? Well, an important point is made by Solmi and colleagues: "Our study was based on PEs in early and late adolescence, unlike other studies which were based on a clinical diagnosis of schizophrenia." In other words. psychotic experiences might be part and parcel of schizophrenia but not necessarily all that schizophrenia encompasses and not necessarily just enough to merit a diagnosis of schizophrenia. They do also go on to highlight how the previous report on the association may also not have included the range of potentially confounding variables that were included and controlled for in the current study as another possibility for the differences reported. Having said that [2]...

Does the T. gondii - schizophrenia hypothesis fall as a result of the Solmi results? Probably not. Solmi et al hint that even though cat ownership probably isn't related to PEs, they do not totally debunk the idea that there may be a connection. They did not for example, look for the presence of contact with T. gondii in this particular study (others have) as per serological examination of participants. I say this bearing in mind that not every moggy is necessarily infected with T. gondii or anything else. Sweeping generalisations on all cats are not required.

Music to close, and containing the lyric 'Caringosity killed the Kerouac cat', a chirpy little number from a band with quite a contentious name...

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[1] Solmi F. et al. Curiosity killed the cat: no evidence of an association between cat ownership and psychotic symptoms at ages 13 and 18 years in a UK general population cohort. Psychol Med. 2017 Feb 22:1-9.

[2] Fuller Torrey E. et al. The antecedents of psychoses: a case-control study of selected risk factors. Schizophr Res. 2000 Nov 30;46(1):17-23.

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Solmi F, Hayes JF, Lewis G, & Kirkbride JB (2017). Curiosity killed the cat: no evidence of an association between cat ownership and psychotic symptoms at ages 13 and 18 years in a UK general population cohort. Psychological medicine, 1-9 PMID: 28222824

HSV-2 gestational infection and offspring autism risk

"In our cohort, high levels of antibodies to herpes simplex virus 2 at midpregnancy were associated with an elevated risk of autism spectrum disorder in male offspring. These findings provide support for the hypothesis that gestational infection may contribute to the pathogenesis of autism spectrum disorder and have the potential to drive new efforts to monitor women more closely for cryptic gestational infection and to implement suppressive therapy during pregnancy."

That was the conclusion reached in the paper published by Milada Mahic and colleagues [1] including the research tag-team that is Mady Hornig and Ian 'virus hunter' Lipkin in the list of contributing authors. Having already received some media attention (see here), it doesn't need much more from me but I do want to include a few details and relevant points in this blog entry.

So, the Autism Birth Cohort was the starting point, and "442 mothers of children with ASD... and 464 frequency-matched controls" who all provided plasma samples "(903 samples acquired at midpregnancy and 878 acquired after delivery)." Said samples were analysed for IgG antibodies to ToRCH agents: "Toxoplasma gondii, rubella virus, cytomegalovirus (CMV), and herpes simplex viruses 1 (HSV-1) and 2 (HSV-2)." Some of those viruses and parasites have previously been mentioned with [some] autism in mind (see here and see here and see here).

Results: well, an important detail first: "Because rubella vaccination is part of the routine child vaccination schedule in Norway, almost all individuals had IgG antibodies to rubella virus." Indeed, other authors have speculated that rubella vaccination has actually "prevented substantial numbers" of autism as a knock-on effect of reducing the numbers of cases of congenital rubella syndrome [2]. Vaccination doing more than just saving lives eh?

Next: "Our data suggest that the presence of high levels of anti-HSV-2 antibodies at midpregnancy increases the risk of ASD [autism spectrum disorder] in boys." The authors complemented this finding by some rather neat statistical wizardry whereby odds ratios were calculated based on "four different anti-HSV-2 reference levels (60, 120, 180, and 240 arbitrary units [AU]/ml)." Having said that: "High levels of antibodies, which are typically indicative of recent infection, were found in only a small number of subjects." They also reported "no statistically significant association with risk was found with high levels of HSV-2 antibodies at delivery" and saw nothing significant when it came to the other infections examined. These important points have been picked up in the NHS Choices entry on this study (see here).

These are interesting findings and, as far as I can see, represent something quite novel to the quite vast autism research landscape (assuming you count maternal HSV-2 levels and not antibody levels in actual people diagnosed with autism). The reliance on data from an initiative like the Autism Birth Cohort ensured some rigour in terms of the diagnosis of autism [3] and with the reputations following Drs Hornig and Lipkin, one would have to be pretty brave to question their virus-hunting credentials also with autism in mind [4].

Then to the million-dollar question: how might elevated HSV-2 antibodies during pregnancy affect offspring risk of autism? There is a familiar theme offered by the authors to this question as per statements like: "ASD risk associated with high levels of antibodies to HSV-2 is not specific to HSV-2 but instead reflects the impact of immune activation and inflammation on a vulnerable developing nervous system." I know some people still have a bit of a problem with the idea that something like maternal immune activation (MIA) might up the risk for various offspring outcomes [hint: if an article contains the word 'truth' in the title, step away] but please, stop with the 'it can never happen' generalisations and instead look to the existing peer-reviewed evidence on the topic [5]. Yes, science needs to do more on the topic of MIA and autism but clues are emerging all the time...

Oh, and I'll be coming to research talking about another member of the herpesviruses in relation to autism quite soon on this blog.

To close, operation hardtack and other videos (best viewed in full-screen mode).

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[1] Mahic M. et al. Maternal Immunoreactivity to Herpes Simplex Virus 2 and Risk of Autism Spectrum Disorder in Male Offspring. mSphere. 2017. Feb 22.

[2] Berger BE. et al. Congenital rubella syndrome and autism spectrum disorder prevented by rubella vaccination - United States, 2001-2010. BMC Public Health. 2011; 11: 340.

[3] Stoltenberg C. et al. The Autism Birth Cohort (ABC): A Paradigm For Gene-Environment-Timing Research. Molecular Psychiatry. 2010;15(7):676-680.

[4] Hornig M. et al. Lack of association between measles virus vaccine and autism with enteropathy: a case-control study. PLoS One. 2008 Sep 4;3(9):e3140.

[5] Careaga M. et al.  Maternal Immune Activation and Autism Spectrum Disorder: From Rodents to Nonhuman and Human Primates. Biol Psychiatry. 2017 Mar 1;81(5):391-401.

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Milada Mahic, Siri Mjaaland, Hege Marie Bøvelstad, Nina Gunnes, Ezra Susser, Michaeline Bresnahan, Anne-Siri Øyen, Bruce Levin, Xiaoyu Che, Deborah Hirtz, Ted Reichborn-Kjennerud, Synnve Schjølberg, Christine Roth, Per Magnus, Camilla Stoltenberg, Pål Surén, Mady Hornig, & W. Ian Lipkin (2017). Maternal Immunoreactivity to Herpes Simplex Virus 2 and Risk of Autism Spectrum Disorder in Male Offspring. mSphere : 10.1128/mSphere.00016-17

Fatty acids and autism meta-analysed yet again (with a different result?)

OK I'm a little confused right now.

Not so long ago I talked about the paper from Horvath and colleagues [1] (see here) concluding that "the limited data currently available suggest that ω-3 FA [omega-3 fatty acid] supplementation does not enhance the performance of children with ASD [autism spectrum disorder]." Such a conclusion was based on the application of a systematic review and meta-analysis of the available peer-reviewed literature up to August 2016.

Now however, another systematic review and meta-analysis on the topic has emerged from Mazahery and colleagues [2] and reported something a little bit different: "Populations with ASD have lower n-3 LCPUFA status and n-3 LCPUFA supplementation can potentially improve some ASD symptoms." Don't you just love science!

OK, so what could be the reason(s) for the differing conclusions reached by the reviews on this topic? Well, Mazahery and colleagues (the most recent review) actually conducted two meta-analyses: "meta-analysis 1 compared blood levels of LCPUFA and their ratios arachidonic acid (ARA) to docosahexaenoic acid (DHA), ARA to eicosapentaenoic acid (EPA), or total n-6 to total n-3 LCPUFA in ASD to those of typically developing individuals (with no neurodevelopmental disorders), and meta-analysis 2 compared the effects of n-3 LCPUFA supplementation to placebo on symptoms of ASD." Horvath et al only conducted one meta-analysis in their study roughly equivalent to meta-analysis 2 presented by Mazahery looking at the effects of fatty acid supplementation on the presentation of autism. Mazahery and colleagues also surveyed the literature up to May 2016 and found four randomised-controlled trials (RCTs) (N=107) whereas Horvath et al (who published earlier!) surveyed the literature up to August 2016 and found five RCTs (N=183). Indeed, it appears that based on that last 'difference' one might see how the grand 'top of the scientific hierarchy' meta-analysis is yet again, only as good as the data it contains. And a certain celebrity in science circles seems to agree...

Where next I hear you ask? Well, I'd be tempted to follow the recommendations of Mazahery and colleagues when they suggest that: "Further research with large sample size and adequate study duration is warranted to confirm the efficacy of n-3 LCPUFA." Indeed, there are already studies to watch in this area. That and recognising that within the vast plurality that is the autisms it is not totally outside the realms of possibility that specific parts of the autism spectrum might be more vulnerable to fatty acid issues than others. Oh, and don't forget that outside of impacting autistic 'performance' (or not), fatty acid supplementation does seem to have other health-related properties too...

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[1] Horvath A. et al. ω-3 Fatty Acid Supplementation Does Not Affect Autism Spectrum Disorder in Children: A Systematic Review and Meta-Analysis. J Nutr. 2017 Jan 11. pii: jn242354.

[2] Mazahery H. et al. Relationship between Long Chain n-3 Polyunsaturated Fatty Acids and Autism Spectrum Disorder: Systematic Review and Meta-Analysis of Case-Control and Randomised Controlled Trials. Nutrients. 2017 Feb 19;9(2). pii: E155.

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Mazahery H, Stonehouse W, Delshad M, Kruger MC, Conlon CA, Beck KL, & von Hurst PR (2017). Relationship between Long Chain n-3 Polyunsaturated Fatty Acids and Autism Spectrum Disorder: Systematic Review and Meta-Analysis of Case-Control and Randomised Controlled Trials. Nutrients, 9 (2) PMID: 28218722