Folate receptor autoantibodies and autism... replicated (yet again)

Ah yes, scientific replication. A cornerstone of good science, when findings are independently reproduced and confidence increases that A is linked to B or Y affects Z (insert other letter from the alphabet as appropriate). No, it doesn't prove anything - proof is not something that sits well with the scientific method - but it does imply that a particular relationship is much more likely not to be just due to chance given a similar answer being found across different investigations and hopefully, different cohorts of people.

The findings reported by Jiaxiu Zhou and colleagues [1] represent scientific replication in action. Not only that, they represent scientific replication covering an increasingly important issue in relation to [some] autism: a possible role for folate receptor autoantibodies (FRAA).

I don't really want to re-type everything describing FRAAs, what they and what they mean, because I've covered such descriptions before on this blog (see here and see here). Suffice to say these are autoantibodies - where the body mounts an immune response against 'self' - that target a particular protein called folate receptor protein alpha which plays an important role in transporting something called 5-methyltetrahydrofolate (5-MTHF) into the brain. 5-MTHF is a biologically active form of folate, a pretty important nutrient by all accounts; and something with some 'significant' autism research history (see here).

Building on various other reports suggesting that FRAAs might be *over-represented* in relation to the diagnosis of autism [2], Zhou et al examined serum samples provided by 40 children diagnosed with an autism spectrum disorder (ASD) and some 42 matched not-autism controls. They were specifically looking for FRAAs as "measured by enzyme-linked immunosorbent assay" bearing in mind there are blocking FRAAs and binding FRAAs.

They reported more frequently finding FRAAs in the serum samples from those with autism compared with controls (77% vs. 54%). The difference was significant and led researchers to conclude that "children with ASDs may have defects in folic acid absorption that play a role in the onset of ASDs."

As you can see, whilst the rates of detection of FRAAs in the serum samples of those with autism are quite frequent, the presence of FRAAs are not something 'autism-specific'. I say that bearing in mind that FRAAs have been reported in various other conditions/states/diseases and are also seemingly influenced by the presence of certain dietary components too, such as milk consumption [3]. But that doesn't mean that they aren't potentially important to [some] autism...

Then to the next question: intervention. What can be done as and when FRAAs are detected? Well, I've talked before about some of the the scientific evidence on the use of folinic acid (leucovorin) in the context of autism and FRAAs (see here), investigated under double-blind, placebo-controlled conditions. Folinic acid represents an alternative way of getting a biological active folate into circulation in the context of FRAAs being detected. It needs quite a bit more investigation with autism in mind, but could be a useful intervention (minus any medical or clinical advice given or intended).

Also, a milk-free diet. I know some people don't like the idea that [some] dietary elements might 'affect' [some] autism, but again, there is some initial peer-reviewed evidence to suggest that a milk-free diet might be able to dampen down things like folate receptor autoimmunity [4]. This added to the already quite voluminous peer-reviewed science suggesting a possible 'diet-related phenotype' in relation to autism [5] that mentions milk (casein) as well as other dietary components (see here).

In short, folate receptor autoantibodies are probably important to at least some autism.

Oh, and while we're on the topic of folate, I see that someone recently has been talking about why a 'one-size-fits-all' model of folic acid use during pregnancy isn't going to cover all the biological bases (see here). The MTHFR (methylenetetrahydrofolate) gene that is mentioned, has also got quite a bit of peer-reviewed research history with autism in mind (see here)...

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[1] Zhou J. et al. High prevalence of serum folate receptor autoantibodies in children with autism spectrum disorders. Biomarkers. 2018 Mar 26:1-9.

[2] Quadros EV. et al. Folate receptor autoantibodies are prevalent in children diagnosed with autism spectrum disorder, their normal siblings and parents. Autism Res. 2018 Feb 2.

[3] Berrocal-Zaragoza MI. et al. High milk consumers have an increased risk of folate receptor blocking autoantibody production but this does not affect folate status in Spanish men and women. J Nutr. 2009 May;139(5):1037-41.

[4] Ramaekers VT. et al. A milk-free diet downregulates folate receptor autoimmunity in cerebral folate deficiency syndrome. Dev Med Child Neurol. 2008 May;50(5):346-52.

[5] Whiteley P. Nutritional management of (some) autism: a case for gluten- and casein-free diets? Proc Nutr Soc. 2015 Aug;74(3):202-7.

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Folate receptor autoantibodies and autism... replicated

I should warn you that this is another of my long posts, so make yourself a cup of tea/coffee/other, get comfy and read on...

"Overall, 76% of the affected children, 75% of the unaffected siblings, 69% of fathers and 59% of mothers were positive for either blocking or binding Ab, whereas the prevalence of this Ab in the normal controls was 29%."

'Normal controls' is not a term that I would use in the context of autism research, but the findings reported by Edward Quadros and colleagues [1] are a cause for some excitement as the topic of folate receptor alpha (FRα) autoantibodies (Abs) and autism receives some welcome interest and importantly, scientific replication (see here).

Just in case you're new to the concept of folate receptor autoantibodies, it all starts with folate (folic acid). Folates are a pretty important range of nutrient for lots of different reasons, not least the role they play in various brain functions. There are however, a variety of conditions where folate and its various metabolites are 'atypical', one of which is called cerebral folate deficiency (CFD). CFD is characterised by low levels of 5-methyltetrahydrofolate (5-MTHF) in cerebrospinal fluid (CSF) despite fairly typical levels of circulating folates in blood. One of the ways that 5-MTHF gets to the brain is via something called the folate receptor protein alpha. It is this pathway that appears to be 'aberrant' in cases of CFD, and hence use of a compound called folinic acid (leucovorin) (also called 5-formyltetrahydrofolic acid), another 'type' of folate', is used as a result of it utilising an alternative system for getting to the brain (the reduced folate carrier, RFC).

Still here? Good. The hows-and-whys of the folate receptor protein alpha being 'dysfunctional' in relation to CFD has focused on particular autoantibodies (where the immune system starts to mount a response against 'self' tissues) called folate receptor autoantibodies. There are two types of autoantibody: blocking and binding antibodies [2]. These autoantibodies block the transport of folate metabolites to places like the CFS and brain. Finally, there are ways and means that these autoantibodies can be detected in serum samples and, outside of CFD, autism has been a focus for such analyses [3] alongside other, potentially related, diagnoses (see here).

Clear as mud right?

So: "families of 82 children with ASD [autism spectrum disorder], 53 unaffected siblings, 65 fathers, and 70 mothers, along with 52 unrelated... controls" were tested for folate receptor alpha (FRα) autoantibodies in the current Quadros study. I should also mention that Quadros is a name that comes up quite a bit with folate receptor alpha (FRα) autoantibodies in mind. As per the opening line of this post, those autoantibodies were detected in a fairly high frequency in families where autism has been diagnosed. The authors note that the presence of such antibodies "may have a familial origin but the risk of developing ASD is likely influenced by other mitigating factors since some siblings who had the antibodies were not affected." True, absolutely true bearing in mind other work on things like the broader autism phenotype for example (see here).

But there's another strand to this work worthwhile talking about... milk. Milk and autism has been something of real interest to my autism research career down the years (see here) and continues to be. Use of a milk-free - casein-free - diet has filled quite a few peer-reviewed science column inches in relation to both behaviour (see here for example) and physiology (see here) for some on the autism spectrum. In relation to those folate receptor alpha (FRα) autoantibodies, consumption of milk seems to have some rather interesting effects on their presence [4]. The suggestion is that there may be some kind of 'cross-reactivity' going on given the 'homology' between human folate receptor alpha (FRα) and bovine (from cows) folate receptor alpha (FRα). This biological mix-up means that "repeated exposure to milk FR in the digestive tract is the likely mechanism for autoantibody generation" [5]. I'm left wondering a few things: (a) did Quadros and colleagues ask about milk consumption and/or was it recorded? and (b) regarding the 'heritability' issue, could this be part of a wider 'autoantibody heritability' issue among families where autism is present? Y'know, based on the idea that autoantibodies and autoimmunity seems to be a recurring theme for at least some people diagnosed with autism (see here) and in their families (see here)?

And finally, a few research direction suggestions to perhaps take this area forward: (a) wide-scale screening for those for those folate receptor autoantibodies when autism is diagnosed to see if the pretty high 'positives' numbers continue, (b) the requirement for a large (LARGE) study looking at both supplementation with folinic acid and use of a milk-free diet to ascertain exactly what symptoms/traits can potentially be impacted, and finally (c) the inclusion of other parameters when looking at the familial element to folate receptor autoantibodies, such as everyone's favourite 'leaky gut' (also reported in other family members [6]) as a 'vehicle' for possible antibody production. Speculative, yes. Testable, also yes.

Oh, and perhaps a little more inquiry into the thyroid connection (see here) too (with links to yet another autoimmune condition mentioned with autism in mind)...

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[1] Quadros EV. et al. Folate receptor autoantibodies are prevalent in children diagnosed with autism spectrum disorder, their normal siblings and parents. Autism Res. 2018 Feb 2.

[2] Frye RE. et al. Blocking and Binding Folate Receptor Alpha Autoantibodies Identify Novel Autism Spectrum Disorder Subgroups. Frontiers in Neuroscience. 2016;10:80.

[3] Ramaekers V. et al. Clinical recognition and aspects of the cerebral folate deficiency syndromes. Clin Chem Lab Med. 2013 Mar 1;51(3):497-511.

[4] Berrocal-Zaragoza MI. et al. High milk consumers have an increased risk of folate receptor blocking autoantibody production but this does not affect folate status in Spanish men and women. J Nutr. 2009 May;139(5):1037-41.

[5] Ramaekers VT. et al. A milk-free diet downregulates folate receptor autoimmunity in cerebral folate deficiency syndrome. Developmental medicine and child neurology. 2008;50(5):346-352.

[6] de Magistris L. et al. Alterations of the intestinal barrier in patients with autism spectrum disorders and in their first-degree relatives. J Pediatr Gastroenterol Nutr. 2010 Oct;51(4):418-24.

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"we found no association between maternal folic acid supplementation and offspring ASD" but...

The findings reported by Marit Strøm and colleagues [1] observing "no association between maternal folic acid supplementation and offspring ASD [autism spectrum disorder]" throw yet another research 'spanner in the works' when it comes to the [very generalised] idea that pregnancy folic acid supplementation might affect risk of offspring autism.

Don't get me wrong, I appreciate all the data suggesting that folic acid supplementation during pregnancy is a useful thing for helping to reduce the risks of neural tube defects (NTDs) for example. But when it comes to pregnancy folic acid (folate) potentially impacting on offspring risk of autism, I've always been a little cautious of the collected data so far and how its been interpreted/generalised in certain quarters (see here and see here for examples).

So, drawing on data from the "entire DNBC [Danish National Birth Cohort]" initially including nearly 100,000 singleton, live born children, researchers set out to find female "users" of folic acid supplements either just before conception or during the earliest stages of their pregnancy. Not just content with folic acid, they also looked at available data on "periconceptional vitamin B12" use too on the basis of some connection between the two vitamins. They then searched connected databases to find those offspring with a diagnosis of autism spectrum disorder (ASD): "identified by International Classification of Diseases (ICD)-10 diagnosis codes F840, F841, F845, F848, and F849; ‘childhood autism’ by diagnosis code F840." Analyses of these collected variables were undertaken, as well as adjusting for potentially confounding variables such as maternal age, parity, education level and the like.

Results: well, as per the title of this post, researchers reported finding very little when it came to pre-pregnancy or early pregnancy folate use: "There was no detectable association between maternal folic acid supplementation in the periconceptional period and offspring ASD" and: "Results from the analyses using midpregnancy exposure data were similar: there was no association with ASD/childhood autism neither for folic acid supplementation nor for dietary folate intake." Such results held when various 'corrections' were made for variables such as "sex specific effects" and cases where intellectual (learning) disability was present for example.

I have to say that the authors do seem genuinely surprised that their results did not tally with other large, population studies on this topic: "At present we are not able to present any viable explanation for these discrepant results." They do mention one particularly important point insofar as the usefulness of looking at small changes to something called the methylenetetrahydrofolate reductase (MTHFR) gene in the context of autism and folic acid as other authors have done [2]. This, on the basis that MTHFR plays an important role in folate metabolism (see here) and issues with this gene are no stranger to the autism research landscape (see here). I'm also minded to refer readers back to another potentially important issue identified in relation to some autism that might also affect folate metabolism: folate receptor autoantibodies (FRAAs) (see here).

I still think there is a place for further investigations on folic acid use during pregnancy and offspring autism risk. But like many things in the context of the plural 'autisms' (see here), it perhaps makes more sense to zoom in on potentially relevant sub-groups on the autism spectrum rather than treating all autism as being homogeneous in either aetiology or presentation. I might add that folic acid use as part of wider range of nutritional supplements potentially used during early pregnancy remains an important area of research attention in the context of offspring autism [3].

And also just to complicate things even further, the results from Wang and colleagues [4] add: "this comprehensive meta-analysis suggested that maternal use of folic acid supplements during pregnancy could significantly reduce the risk of ASD in children regardless of ethnicity, as compared to those women who did not supplement with folic acid." I don't think the debate is finished yet on this topic.

Music to close, and since my brood and I are competing again today, Sia (again) and some brilliant kata (hopefully our Heian Sandan will be as good).

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[1] Strøm M. et al. Research Letter: Folic acid supplementation and intake of folate in pregnancy in relation to offspring risk of autism spectrum disorder. Psychol Med. 2017 Sep 26:1-7.

[2] Schmidt RJ. et al. Maternal periconceptional folic acid intake and risk of autism spectrum disorders and developmental delay in the CHARGE (CHildhood Autism Risks from Genetics and Environment) case-control study. Am J Clin Nutr. 2012 Jul;96(1):80-9.

[3] DeVilbiss EA. et al. Antenatal nutritional supplementation and autism spectrum disorders in the Stockholm youth cohort: population based cohort study. BMJ 2017; 359: j4273.

[4] Wang M. et al. The association between maternal use of folic acid supplements during pregnancy and risk of autism spectrum disorders in children: a meta-analysis. Molecular Autism. 2017; 8: 51.

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One more time folks... pregnancy folate and autism risk

Folate yet again on this blog? Sorry but that's just how the peer-reviewed papers have fallen...

"Maternal folate supplementation during pregnancy may reduce the risk of ASD [autism spectrum disorder] in the offspring, especially in the Western population."

So said the meta-analysis by Yu and colleagues [1] reporting on a topic that has seen quite a lot of research interest down the years (see here). Authors this time around cumulatively examined data for some 4,500 cases of autism compared with well over a million control (not-autism) cases and determined that on the whole "maternal folate supplementation during pregnancy significantly reduced the risk of ASD in the offspring in the total population (OR=0.798, 95%CI: 0.669-0.952, P=0.012)."

What more is there to say on this topic? Well, potentially quite a bit, not least that not every study has suggested that folate is necessarily a risk reducer when it comes to offspring autism (see here) bearing in mind the potential number of confounders affecting any relationship. Of the multiple occasions that I've talked about folate and autism on this blog, I'm also minded to bring back into the frame how (a) the folate cycle, dealing with the biological metabolism of folate, and its related components is pretty complicated when it comes to a label like autism (see here) and (b) one area that is becoming particularly interesting is in relation to antibodies and folate receptors (see here for example) with autism in mind. Science still needs to do quite a bit more in relation to mechanics of any link between pregnancy folate use/levels and offspring autism risk.

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[1] Yu XF. et al. Association between maternal folate supplementation during pregnancy and the risk of autism spectrum disorder in the offspring: a Meta analysis. Zhongguo Dang Dai Er Ke Za Zhi. 2017 Mar;19(3):286-291.

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Yu XF, Li M, & Zheng Y (2017). [Association between maternal folate supplementation during pregnancy and the risk of autism spectrum disorder in the offspring: a Meta analysis]. Zhongguo dang dai er ke za zhi = Chinese journal of contemporary pediatrics, 19 (3), 286-291 PMID: 28302198

Blocking FRAAs and thyroid function in autism (continued)

Readers of this post are advised to check out a previous blogging occasion describing how 'FRAAs - folate receptor alpha autoantibodies - may correlate with reduced thyroid function in cases of autism' before heading into this entry on the recent paper published by Richard Frye and colleagues [1].

You're back already? OK, well just in case you didn't read that last entry (😉), it's worthwhile first noting that: "Folate receptor α (FRα) autoantibodies (FRAAs) are prevalent in autism spectrum disorder (ASD). They disrupt the transportation of folate across the blood-brain barrier by binding to the FRα. Children with ASD and FRAAs have been reported to respond well to treatment with a form of folate known as folinic acid, suggesting that they may be an important ASD subgroup to identify and treat." Those are author words not mine (as is the clinical intervention mention).

The 'thyroid' addition to their recent paper follows that previous paper by the authors [2] stating that: "blocking FRAAs are associated with reduced thyroid function and suggest that thyroid function should be examined in children with ASD who are positive for the blocking FRAAs."

This time around the authors examined "blocking and binding FRAAs and thyroid stimulating hormone (TSH), free T4 (FT4), total T3 (TT3), reverse T3 (rT3), thyroid releasing hormone (TRH) and other metabolites" in 87 children diagnosed with an ASD. Some of their cohort had more than one measure of FRAAs, TSH and FT4.

Results: "TSH, TT3 and rT3 were above the normal range in 7%, 33% and 51% of the participants and TRH was below the normal range in 13% of the participants." Further: "TSH concentration was positively and the FT4/TSH, TT3/TSH and rT3/TSH ratios were inversely related to blocking FRAA titers." The observation that levels of thyroid stimulating hormone (TSH) were positively correlated with blocking FRAA titers follows the same pattern as the previous findings reported by authors. Elevations in TSH normally imply that the 'thyroid is struggling' and potentially leaning towards hypothyroidism; the correlation with FRAA titers *could* imply that those blocking antibodies might be part and parcel of why the thyroid is struggling. Ergo: "This study suggests that thyroid dysfunction in ASD may be related to the blocking FRAA."

Accepting that 'FRAA autism' (if I can call it that) is not a universal label to be applied to the autism spectrum (see here) the combined results in this area (with and without the thyroid bit added on) make for interesting reading. Not only do they offer yet another strand to the saying 'an autism diagnosis is the starting not finishing point' when it comes to assessments, but the possible intervention angle also comes to the forefront (see here).

What else would I like to see in this area? Well, quite a bit more work on thyroid function and autism could be a good starting point, outside of the maternal thyroid function (autoimmunity) and offspring risk bit (see here). Given that also all those thyroid metabolites are reliant on iodine (the number referring to the number of iodine units chemically attached), there could be quite a bit more to see when it comes to iodine and [some] autism too (see here). Then another research question: what happens to thyroid function as and when something like folinic acid is used? Science already has some idea that folinic acid - under double-blind, placebo-controlled conditions - might be useful for aspects of some autism (see here). Could we learn from other studies looking at folinic acid where thyroid function has been mentioned? [3] I daresay we could...

To close, science is great. Especially when it talks about case reports like this...

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[1] Frye RE. et al. Thyroid dysfunction in children with autism spectrum disorder is associated with folate receptor alpha autoimmune disorder. J Neuroendocrinol. 2017 Feb 15.

[2] Frye RE. et al. Folate Receptor Alpha Autoantibodies Modulate Thyroid Function in Autism Spectrum Disorder. NAJ Med Sci. 2014; 7: 53-56.

[3] Blehaut H. et al. Effect of leucovorin (folinic acid) on the developmental quotient of children with Down's syndrome (trisomy 21) and influence of thyroid status. PLoS One. 2010 Jan 11;5(1):e8394.

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Frye RE, Wynne R, Rose S, Slattery J, Delhey L, Tippett M, Kahler SG, Bennuri SC, Melnyk S, Sequeira JM, & Quadros E (2017). Thyroid dysfunction in children with autism spectrum disorder is associated with folate receptor alpha autoimmune disorder. Journal of neuroendocrinology PMID: 28199771

Pregnancy folic acid and offspring autism systematically reviewed

"A total of 22 original papers that examined the association between folic acid supplementation in human pregnancy and neurodevelopment/autism were identified after the screening, with 15 studies showing a beneficial effect of folic acid supplementation on neurodevelopment/autism, 6 studies showed no statistically significant difference, while one study showed a harmful effect in > 5 mg folic acid supplementation/day during pregnancy."

That rather long quote taken from the paper published by Yunfei Gao and colleagues [1] (open-access) opens today's post and provides a welcome [peer-reviewed] overview of where science is up to when it comes to the effects (or not) of pregnancy folic acid supplementation on 'risk' of offspring autism. I say 'where the science is up to' but at the same time note that the various searches of databases for material relevant to this topic/review was carried out up to the end of 2014. There have been other reports since that date including other reviews [2]...

Folic acid or folate in the context of autism has been a recurrent research theme down the years. Outside of the protective effects of pregnancy folate use with regards to reducing the risk of offspring neural tube defects (NTDs), the suggestion that pregnancy folic acid may confer a protective effect against offspring autism has been highlighted in several studies (see here).

Gao et al trawled the research literature and "included randomized controlled trials (RCTs), cohort studies, and case control studies that examined the association between folic acid supplementation during pregnancy and neurodevelopment/autism in the offspring children." As per that lengthy opening sentence from their paper, the authors found data that on the whole suggested that folate supplementation was protective rather than harmful when it came to offspring developmental outcomes. Given that most/many pregnant women are already taking folic acid during pregnancy to counter the risk of NTDs, this is good news indeed.

Without giving any undue weight to those studies that have perhaps not been so enthusiastic about the link between pregnancy folate use and offspring autism risk (see here) I do think there are words of caution in this area too. We're still for example, waiting for research to be published that was raised at this years IMFAR event in relation to folic acid and autism (see here). Indeed, in my discussion of that so-far-unpublished work, I mentioned that the genetics of folic acid metabolism also needs to be further inspected when it comes to autism (see here) and that screening for particular issues linked to folate might be something to consider for people on the autism spectrum and their significant others (see here). Both these areas are potentially relevant to that recent chatter on how folinic acid might be useful for some aspects of some autism (see here).

"Large scale RCTs with validated diagnosis and high follow up rate are needed in order to produce robust evidence regarding the effects of folic acid supplementation in pregnancy on fetal neurodevelopment" conclude the authors. Yes, we need more investigation of this area - including what effect certain medicines used during pregnancy might have had on folate levels -  but for now, the data seems to side with a protective effect of folate supplementation in pregnancy when it comes to offspring risk of autism or related neurodevelopmental issues.

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[1] Gao Y. et al. New Perspective on Impact of Folic Acid Supplementation during Pregnancy on Neurodevelopment/Autism in the Offspring Children – A Systematic Review. PLoS ONE. 2016; 11(11): e0165626.

[2] DeVilbiss EA. et al. Maternal folate status as a risk factor for autism spectrum disorders: a review of existing evidence. Br J Nutr. 2015 Sep 14;114(5):663-72.

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Gao Y, Sheng C, Xie RH, Sun W, Asztalos E, Moddemann D, Zwaigenbaum L, Walker M, & Wen SW (2016). New Perspective on Impact of Folic Acid Supplementation during Pregnancy on Neurodevelopment/Autism in the Offspring Children - A Systematic Review. PloS one, 11 (11) PMID: 27875541

"Folinic acid improves communication in childhood autism"

A quote to begin: "... in this small trial of children with non-syndromic ASD [autism spectrum disorder] and language impairment, treatment with high-dose folinic acid for 12 weeks resulted in improvement in verbal communication as compared with placebo, particularly in those participants who were positive for FRAAs [folate receptor-α autoantibody]."

Those were the findings reported by Richard Frye and colleagues [1] (open-access) continuing a research theme from this group looking at how folinic acid - a reduced form or vitamer of folate - may "markedly" improve symptoms in some children diagnosed with ASD (see here). Some media reporting about these latest results are available (see here for example) but if you're sticking with my interpretation there are a few important points to note.

So:

• This was a gold-standard "double-blind, randomized placebo-controlled" study meaning that as well as pitting folinic acid against a placebo, both researchers and participants were blind to 'who got what' during the 12 weeks of study. The aim was to compare a "target dose" of folinic acid "(2 mg kg−1 per day)" with said placebo formulation. It also appears that the authors went to some lengths to ensure that folinic acid and placebo capsules were "indistinguishable by sight and feel" as well as odour and taste.
• Participants (~7 years old) (N=48) were allocated to the folinic acid (n=23) or placebo group (n=25). All had a diagnosis of ASD and importantly, "Reconfirmation of the diagnosis using the lifetime version of the Autism Diagnostic Interview-Revised by an independent research reliable rater was requested from all participants." Participants were also required to have "documentation of language impairment" accompanying their autism as well as being free from current antipsychotic medication use alongside various other inclusion/exclusion criteria.
• "Verbal communication was the primary outcome" we are told, offering a rather refreshing prospect insofar as the focus being on symptoms rather than syndromes. That's not to say that various behavioural schemes pertinent to the presentation of autism and other general 'adaptive behaviours' weren't also included, but this was a study looking specifically at what happened to verbal communication.
• Results: well, first and foremost folinic acid seemed to be pretty safe and well tolerated as we are told that "no serious adverse effects" were recorded for the folinic acid group when blinding was broken. First, do no harm and all that. As per the opening sentence of this post, there were some significant group improvements noted for the group taking folinic acid in relation to verbal communication ("an important core ASD symptom") compared with the placebo group.
• Going back to the whole 'positive for FRAAs' there were also some results to be seen. "This study suggests that FRAAs predict response to high-dose folinic acid treatment. This is consistent with the notion that children with ASD and FRAAs may represent a distinct subgroup." Without turning this post into some grand explanation of what FRAAs are (bearing in mind I'm barely getting my head around this myself), this ties into other findings (see here) and how these autoantibodies work to impair folate transport and 'block' or 'bind' to the folate receptor. One explanation is that folinic acid is able to 'bypass the FRα [folate receptor-α] when it is blocked and/or dysfunctional' particularly at higher doses. The use of the term "distinct subgroup" when it comes to autism is music to many ears in these days of the more plural 'autisms' and recognition that certain inborn errors of metabolism seem to be associated with 'some types' of autism [2] (more on this paper to come soon).

Of course there is more to do in this area as the authors themselves identify the small participant numbers as one limitation and the future requirement to "determine the optimal folinic acid dose". Although no adverse effects were reported during the 12-week period, I'd also suggest that longer-term follow-up is needed to make sure that this effect extends a little longer too. Given the folate connection evident in this line of research, I'd for example, also be interested to see a little more work done on whether everyone's favourite scrabble gene - methylenetetrahydrofolate reductase (MTHFR) - potentially linked to some autism (see here) might also be an important player with regards to folinic acid use and response. Finally, minus any sweeping generalisations, the idea that FRAAs might also extend across labels to schizophrenia (see here) for example, is also potentially worthy of further investigation insofar as the 'links' that still remain when it comes to the autism and schizophrenia spectrums (see here) (remembering too the important work of Mildred Creak).

Having said all that, these are important results as they stand. Not least because under rigorous methodological conditions, folinic acid has seemingly passed yet another scientific hurdle with regards to its potential relevance to at least some autism. We will no doubt see more on this topic in the peer-reviewed literature in times to come...

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[1] Frye RE. et al. Folinic acid improves verbal communication in children with autism and language impairment: a randomized double-blind placebo-controlled trial. Molecular Psychiatry. 2016. Oct 18.

[2] Simons A. et al. Can psychiatric childhood disorders be due to inborn errors of metabolism? European Child & Adolescent Psychiatry. 2016. Sept 30.

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Frye, R., Slattery, J., Delhey, L., Furgerson, B., Strickland, T., Tippett, M., Sailey, A., Wynne, R., Rose, S., Melnyk, S., Jill James, S., Sequeira, J., & Quadros, E. (2016). Folinic acid improves verbal communication in children with autism and language impairment: a randomized double-blind placebo-controlled trial Molecular Psychiatry DOI: 10.1038/mp.2016.168

Folate, autism and IMFAR: keep calm

IMFAR - The International Meeting for Autism Research - has just closed it's doors, bringing to an end one of the premier annual autism research conferences where one might expect quite a few of the presentations to eventually become (peer-reviewed) fodder for this blog.

This year (2016) has seen yet another startling array of research papers covering all manner of topics pertinent to autism; it's presumed aetiologies (plural as per the 'autisms'), diagnosis and management, all discussed and dissected. This year also saw some well needed focus on other important issues linked to autism such as various (medical and psychiatric) comorbidity linked to the label, the idea that children with autism become autistic adults (mostly) and the rather distressing idea that suicide (ideation or actual) seems to be over-represented when a diagnosis is received. Without trying to portray too negative an image of the very wide autism spectrum, autism can in some cases be a life-limiting as well as a life-changing condition (see here and see here).

As an outsider looking in on proceedings (#IMFAR2016) I was particularly interested in a few discussions that were covered during the event. This included the keynote address delivered by Irva Hertz-Picciotto on how, despite various environmental agents being traditionally correlated with some 'types' of autism (rubella, valproic acid), there are still challenges in terms of putting environmental factors on a par with genetic issues for example. Indeed, one or two tweets about her presentation kinda summed up the stark lack of knowledge and expertise in this area; specifically how 'chemical' insults (being careful with that word) potentially linked to cases of autism or at least autistic traits, already pervade the peer-reviewed literature (see here for example). It seems we need to further organise how research is done in this area, where exposure and genetic fragility are taken into account alongside the idea of synergy when it comes to the chemical soup that we all live in [1]; similar to the idea that multiple genes might be involved in multiple autisms so multiple non-genetic exposures might also show a connection (might I also suggest a greater focus on subgroups on the 'autisms' spectrum too?)

One of the other 'environmental' factors that was raised at IMFAR 2016 was that of folate (folic acid) and the possibility of a connection between pregnancy levels of this stuff and some autism as per the paper by Ramkripa Raghavan and colleagues [2]. For those who might already be well-read in autism research, the idea that maternal levels of folate during pregnancy might have a bearing on risk of offspring autism is not a new one (see here). With sentiments not a million miles away from those proposed by the late David Barker and the 'foetal programming hypothesis', the collected research on folate availability/supplementation during pregnancy impacting on the developing child is still the topic of some discussion (see here and see here). What is clear is that much like the need for folate during pregnancy to reduce the risk of neural tube defects, there may also be additional developmental requirements for suitable levels when it comes to other outcomes too.

Rather interestingly however, the data from Raghavan et al was not all one way when it came to 'risk' of offspring autism and levels of folate and a related nutrient, vitamin B12. To quote from their un-peer-reviewed paper: "In this urban low-income minority birth cohort, we observed an elevated risk of ASD [autism spectrum disorder] associated with high maternal plasma folate levels (>59 nmol/L), which far exceeds the excess cutoff suggested by the WHO (>45.3 nmol/L). Excess maternal vitamin B12 (>600 pmol/L) was also shown to be associated with greater ASD risk in offspring.  The risk of ASD was highest if mothers had both excess in folate and B12 levels." As you might imagine, the accompanying press release that followed this un-peer-reviewed paper was snapped up by various media outlets with titles like: "Taking too many vitamins during pregnancy 'can treble children's risk of being autistic'". Lo and behold, we have yet another 'scare story'...

Accepting that this was un-peer-reviewed research and that inflated press releases seem to abound in the domain of science communication (see here) I was a little less ruffled by the data reported by Raghavan and colleagues. I can see why such findings might make great headlines - "The risk was greatest for those children whose mothers had both high plasma folate (>59 nmol/L) and vitamin B12 (>600 pmol/L) (HR [adjusted hazard ratio]: 17.59; p value: <0.001)" - but this is not the first time that such sentiments have been expressed with relation to autism. Indeed, on a previous post asking whether some of the data of pregnancy folate levels/supplementation and offspring autism risk might not be just all about deficiency (see here) I discussed some rather speculative ideas (albeit peer-reviewed ideas) about how there may be a balance to be struck between potentially too little and too much of a good thing.

'Scientists urge caution over 'alarmist' claim of link between pregnancy folate and autism' was a rather more restrained headline in relation to the Raghavan report. I was much happier with this headline and coverage that put into perspective the preliminary nature of the report (yes, un-peer-reviewed) and how: “There are many epidemiologically based associations made of this sort – increasingly so in autism at the moment." Indeed there are, but unfortunately the commentator goes on to say that "Without details of the analysis, or any theory of action this looks like low-grade evidence."

Actually there are 'theories of action' and they've been discussed quite a bit in the peer-reviewed literature in this area. Not least, the idea that folate and vitamin B12 are important compounds in something called the folate cycle which intersects with another set of important metabolic process: the methylation cycle (see here) and all that DNA methylation stuff. There are a number of possible 'issues' that might be autism-relevant in these biological cycles, not least related to something called MTHFR (see here) and some emerging data on folate receptor autoantibodies (see here). Issues with these systems could very much impact on how folate is used and whether high plasma folate for example, might not be just as the result of too much supplementation. As per what we know from data from more formal medicines, drug metabolism can be quite an individual thing.

I do also want to bring in a little more data about vitamin B12 and 'some' autism as potentially being relevant. Accepting that there has been very little data on maternal vitamin B12 levels and offspring autism, there is certainly quite a bit of data out there about 'issues' with vitamin B12 being tied into specific cases of autism. This year (2016) we've seen the results of placebo-controlled study on the use of methyl B12 for aspects of autism (see here) as well as a suggestion that decreased brain levels of vitamin B12 might link cases of autism and schizophrenia (see here). That severe vitamin B12 deficiency has been linked to cases of Heller's syndrome is also potentially important (see here) given the focus on 'regression'...

Cumulatively what the Raghavan and other data point to is a potentially complicated relationship between mother's nutrition during pregnancy and offspring outcomes. I don't say this to somehow hark back to the darker days of autism theory in terms of 'blame' but rather, alongside other lines of evidence, to point out that nutrition during the nine months that made us (and perhaps earlier) plays an important role in making us who we are. The way that said nutrition is metabolised is also likely to vary from person to person. Minus sweeping generalisations and inflated media headlines, a greater research focus on how that nutrition might impact on at least some autism is very much implied again keeping in mind all that individuality in terms of how the body 'processes' nutrition. Indeed, for those mums identified in the Raghavan data as showing high levels of folate and vitamin B12, in the spirit of scientific endeavour, I'd be asking 'why?' and what does it mean for other related markers such as 'the big H' (homocysteine) for example?

For now however, keep calm and carry on with Love, love, peace, peace (song starts after 1 minute).

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[1] Boggess A. et al. Mean serum-level of common organic pollutants is predictive of behavioral severity in children with autism spectrum disorders. Sci Rep. 2016 May 13;6:26185.

[2] Raghavan R. et al. Maternal Plasma Folate, Vitamin B12 Levels and Multivitamin Supplement during Pregnancy and Risk of Autism Spectrum Disorders in the Boston Birth Cohort. IMFAR 2016; 22533. [NOT PUBLISHED IN A PEER-REVIEWED JOURNAL]

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Folate receptor autoantibodies (FRAAs) and a 'type' of autism?

"This study suggests that FRAAs [folate receptor α (FRα) autoantibodies] are associated with specific physiological and behavioral characteristics in children with ASD [autism spectrum disorder] and provides support for the notion that these biomarkers may be useful for subgrouping children with ASD, especially with respect to targeted treatments."

So said the study findings published by Richard Frye and colleagues [1] (open-access) who continued a research theme looking at FRAAs and their manifestation in 'some' autism. If you've already clicked that link in the last paragraph, you should have something of a flavour for what FRAAs are and what has already been discussed with autism in mind. If you didn't, the long and short of it is FRAAs describing the possibility of issues with folate transport as noted in the condition cerebral folate deficiency (CFD) are also being reported alongside some autism. The subsequent use of folinic acid (a vitamer of folic acid) to compensate might be something to consider for at least some on the autism spectrum bearing in mind my not giving any medical or clinical advice. I might also direct readers to a previous post with a helpful graphic on how the folate cycle also links in to some other important metabolic processes (see here) which is particularly timely in light of more publications on the topic of 'MTHFR'. I'll come back to this shortly.

This time around, Dr Frye and colleagues set about looking at whether those with autism also with issues around FRAAs present with a 'specific type' of autism, also taking into account different types of FRAAs - blocking and blinding. Serum samples for 94 children diagnosed with an ASD were analysed for blocking and binding FRAAs. At the same time, various markers covering redox, methylation, immune function and vitamin status were also determined and various measures of behaviour examined.

Results: "Fifty seven percent of the participants were positive for either the blocking or binding FRAAs, with 17% positive for blocking FRAA and 51% positive for the binding FRAA; 11% were positive for both FRAAs." From a behavioural/psychometric perspective: "ASD children positive for the blocking FRAA demonstrated better communication on the Vineland Adaptive Behavior Scale, stereotyped behavior on the Aberrant Behavioral Checklist and mannerisms on the Social Responsiveness Scale." In other words, those children with evidence of FRAAs, particularly blocking FRAAs, seemed to "have less severe ASD symptoms." The authors make mention of the term 'optimal outcome' with regards to this group, which is interesting when you consider the status of this often contentious line of research (see here).

The results of the various biological assays employed showed some interesting results. So: "ASD children with the blocking FRAA appear to have a more favorable redox and inflammation profile with relatively better glutathione and CT [3-Chlorotyrosine] indices than FRAA blocking negative children." Further, although folate levels were not significantly different between the groups on the basis of the presence of blocking or binding FRAAs (or neither), levels of vitamin B12 did show some differences: "Children positive for the binding FRAA were found to have higher serum B12 levels as compared to those negative for binding FRAAs."

Appreciating that it is still early days when it comes to FRAAs and autism, this and other research is crying out for independent replication with some appropriate cautions that FRAAs are not seemingly just confined to a diagnosis of autism (see here). The idea that those with autism with a specific type of FRAA (blocking) might present with a more favourable ASD profile in terms of symptoms and also biochemistry invites the question of whether the presence of such biology might actually be 'beneficial' bearing in mind the limited participant numbers included in the Frye study. I know that this might sound at odds with the whole folate-autism link that has been built up over the years, but as I've said before on this blog, folate metabolism and autism is a mighty complicated topic (see here). Likewise, is the idea that the presence of binding FRAAs might be something to 'target' given their seemingly less favourable biological and behavioural profile.

I do have one or two other points to make before I leave you. First, although mention is made of serum levels of the various biological analytes under investigation, one should be mindful of how representative these values are across the body. High serum vitamin B12 does not necessarily mean high brain levels of vitamin B12 for example (and alongside vitamin B12 I would have liked to have seen some data on the compound that is methylmalonic acid). Second, although mention is made of "methylenetetrahydrofolate reductase" (MTHFR), it would be interesting to see how many of the group presented with genetic issues with the production of this enzyme in light of previous findings (see here) and onwards the nature of any connection with FRAAs and autism.

This is interesting work but lots more investigation is implied.

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[1] Frye RE. et al. Blocking and Binding Folate Receptor Alpha Autoantibodies Identify Novel Autism Spectrum Disorder Subgroups. Front. Neurosci. 2016. March 9.

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Frye, R., Delhey, L., Slattery, J., Tippett, M., Wynne, R., Rose, S., Kahler, S., Bennuri, S., Melnyk, S., Sequeira, J., & Quadros, E. (2016). Blocking and Binding Folate Receptor Alpha Autoantibodies Identify Novel Autism Spectrum Disorder Subgroups Frontiers in Neuroscience, 10 DOI: 10.3389/fnins.2016.00080

Pregnancy folic acid and offspring autism risk: just one minute...

So: "We did not find any evidence to corroborate previous reports of a reduced risk for autism spectrum disorders in offspring of women using folic acid supplements in early pregnancy."

The findings reported by Jasveer Virk and colleagues [1] prove once again that when it comes to autism, universal 'truths' are very much few and far between.

Actually, I'm not particularly surprised that Virk et al found what they did when it came to the idea that "early folic acid supplementation during pregnancy prevents diagnosis of autism spectrum disorders in offspring" (their words, not mine). As I've indicated before on this blog, the buzz about how folic acid intake during the nine months (plus) that made us might reduce the risk of offspring autism has not been all one way traffic (see here). Even recent meta-analyses have agreed on this point (see here).

Based on data derived from some familiar registries (Denmark does it again) researchers "estimated risk ratios for autism spectrum disorders for children whose mothers took folate or multivitamin supplements from 4 weeks prior from the last menstrual period through to 8 weeks after the last menstrual period (-4 to 8 weeks) by three 4-week periods." They concluded that there wasn't too much to see when it came to early folate or multivitamin intake in terms of offspring autism outcomes or not compared with women reporting no supplement use during the same period.

That all being said, I don't think it is yet time to trash the whole idea that pregnancy folic acid supplementation might not show some relationship to offspring outcomes with autism in mind. Bearing in mind other data in this area (see here) including the idea that genetic factors might intersect with things like folate availability and utility (see here) I'd be minded to suggest that there is still quite a bit more science to do in this area. Oh, and that issues with folate receptors in relation to some autism, might extend a lot further than just pregnancy (see here) also needs to be kept in mind...

Music: George Ezra - Listen to the Man (in this case, Magneto).

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[1] Virk J. et al. Preconceptional and prenatal supplementary folic acid and multivitamin intake and autism spectrum disorders. Autism. 2015 Sep 25. pii: 1362361315604076.

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Virk J, Liew Z, Olsen J, Nohr EA, Catov JM, & Ritz B (2015). Preconceptional and prenatal supplementary folic acid and multivitamin intake and autism spectrum disorders. Autism : the international journal of research and practice PMID: 26408631

Maternal folate status and offspring autism risk: where are we up to?

I'd like to briefly draw your attention to the review published by Elizabeth DeVilbiss and colleagues [1] today, covering "what is known about the role of folate in the aetiology of neurodevelopmental disorders."

Folate, is a topic that has graced this blog a few times with autism in mind (see here for example) based on various ideas that folate status during pregnancy might have the ability to modify offspring risk of autism [2] alongside the idea that autoimmune processes might act on folate receptors in some cases of autism (see here) and what this might subsequently mean for pathology / management. The specific idea that folate levels and folate supplementation during pregnancy might influence autism risk has garnered the most research attention, seemingly also crossing geographies too [3].

The DeVilbiss review is quite comprehensive in its scope and material covered, summarising "relevant biological, genetic and epigenetic mechanisms" and the various science that has been done so far on this topic. I would certainly agree with their sentiments that "existing evidence is inconclusive" (as previously indicated) in light of the numerous confounding variables also potentially linked to offspring autism risk. That being said, and acknowledging where folate metabolism sits in terms of areas such as MTHFR genetics (see here) and the whole vitamin B12 story (see here) and perhaps beyond (see here), I do think there is more to see in this area and perhaps outside of autism and related neurodevelopmental conditions (see here). Without jumping on the whole epigenetics bandwagon, the link between the folate cycle and DNA methylation in particular (see here) offers a whole slew of research ideas ripe for further investigation.

Music: Lost Frequencies - Are You With Me.

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[1] DeVilbiss EA. et al. Maternal folate status as a risk factor for autism spectrum disorders: a review of existing evidence. Br J Nutr. 2015 Aug 5:1-10.

[2] Schmidt RJ. et al. Maternal periconceptional folic acid intake and risk of autism spectrum disorders and developmental delay in the CHARGE (CHildhood Autism Risks from Genetics and Environment) case-control study. Am J Clin Nutr. 2012 Jul;96(1):80-9.

[3] Surén P. et al. Association between maternal use of folic acid supplements and risk of autism spectrum disorders in children. JAMA. 2013 Feb 13;309(6):570-7.

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DeVilbiss EA, Gardner RM, Newschaffer CJ, & Lee BK (2015). Maternal folate status as a risk factor for autism spectrum disorders: a review of existing evidence. The British journal of nutrition, 1-10 PMID: 26243379

Blocking FRAAs and thyroid function in autism

FRAAs - folate receptor alpha autoantibodies - may correlate with reduced thyroid function in cases of autism is the primary finding from the paper by Richard Frye and colleagues [1] (open-access). And immediately my attention is piqued at the possibility of a link...

FRAAs have been mentioned before on this blog (see here) based on a really interesting paper by the autism research tag team that is Frye and Rossignol [2] who continue to give when it comes to peer-reviewed research on autism. On that occasion, they reported: "serum FRA [folate receptor α autoantibodies] concentrations were measured in 93 children with ASD [autism spectrum disorder] and a high prevalence (75.3%) of FRAs was found". The net result was that there may be issues with the availability of folate, and as in the condition cerebral folate deficiency (CFD), there may be some use in looking at folinic acid (leucovorin) to normalise levels of 5-methyltetrahydrofolate. But please note I'm advocating nothing on this blog just describing findings.

In their most recent paper, Dr Frye and colleagues took things one stage further:

• Levels of blocking and binding FRAAs were measured from serum samples donated by 32 children diagnosed with an autism spectrum disorder (ASD). Based on participants' medical records, levels of thyroid stimulating hormone (TSH) were "abstracted" and correlated with FRAAs measures.
• Results: bearing in mind this was a 'let's see' study with no control groups and TSH values derived from medical records, the authors reported: "No significant relationship was found between the binding FRAA and TSH. However, a higher blocking FRAA titer was significantly related to a higher TSH concentration". The correlation (r) came out at 0.36, which is OK but not necessarily what one might call a strong relationship.
• They add: "Patients who were positive for the blocking FRAA were found to have a significantly higher TSH concentration as compared to patients who were negative for the blocking FRAA". 

There are a few other points to comment on in this paper. First is the focus on thyroid function and autism. I've talked a few times about maternal thyroid levels and how they may correlate to some extent with autism risk (see here and see here). The research literature on thyroid levels in people with autism is slightly more scant (see here), and bearing in mind that there are various other thyroid measures that might be relevant, the focus on TSH alone rather limits the conclusions one can draw about thyroid function in this study. Indeed, none of the participants in this sample had "an abnormally low TSH" result and only a few had "abnormally elevated TSH".

Allied to thyroid function, and mentioned by Frye et al is the issue of iodine deficiency, which again, has been mentioned on this blog with autism in mind (see here). Iodine plays an important role in the production of thyroid hormones. Unfortunately the current study did not assay for iodine levels so we are to some extent left in the dark about any role.

There's little more for me to say about this trial outside of the need for studies looking at rather more direct measures, and a few more of them particularly pertinent to the functions of the thyroid in an autism group. I might also add that in view of the suggestion that a milk-free diet "downregulates folate receptor autoimmunity" as per the work by Ramaekers and colleagues [3] (open-access) looking at CFD, future research might also assess any effect this might have on any thyroid link too. Got milk (opioid peptides)?

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[1] Frye RE. et al. Folate receptor alpha autoantibodies modulate thyroid function in autism spectrum disorder. NAJMS 2014; 7: 53-56.

[2] Frye RE. et al. Cerebral folate receptor autoantibodies in autism spectrum disorder. Mol Psychiatry. 2013; 18: 369-381.

[3] Ramaekers VT. et al. A milk-free diet downregulates folate receptor autoimmunity in cerebral folate deficiency syndrome. Dev Med Child Neurol. May 2008; 50(5): 346–352.

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Richard E. Frye, Jeffrey M Sequeira, Edward Quadros, & Daniel A. Rossignol (2014). Folate receptor alpha autoantibodies modulate thyroid function in autism spectrum disorder N A J Med Sci. , 7 (2), 53-56 : 10.7156/najms.2014.0702053