Thursday, July 30, 2009

Distorting science for traffic

Photo by kikisdad (flickr)

Like everyone, I have my pet peeves - those small things that will annoy me to no end even though most people would think the thing it is no big deal. One of my largest pet peeves is when media outlets or blogs do not accurately report on scientific research or they skew the results to make for a more sensational story.

The world of autism has more than its fair share of misinformation and really doesn't need more.

Take for example a recent post by Lisa Jo Rudy at entitled Autism Caused by Breast Milk?!. From the opening line of -
Could breastfeeding cause autism?!
to the closing line of -
Would it have an impact on your decision to breast feed your child?
the post talks about the possible link between breast feeding and autism based on the result of a "new" study (the study is over 2 years only).

Yet, if you go read the actual study (open access) what you find is a study about exposure to PCBs and developmental issues. Specifically, it looks at how the rat brains develop differently when they are exposed to a high level of PCBs very early in life. This study is an excellent example of how it is possible for chemicals in the environment to cause developmental problems.

But it certainly isn't about breast feeding causing autism as the title of post implies. If you read the study you see that the researchers fed the rats the PCBs almost from the start of pregnancy to when the infant rats were weaned. So the link to breast feeding comes into play because PCBs can be passed from the mother to the infant in breast milk. But then again they can also be passed during the prenatal period across the placenta - the study doesn't differentiate between the two methods.

So the real point of the study is that PCBs can be passed from the mother to her offspring and, if the exposure is high enough, can cause developmental problems. When it comes to the "dangers" of breast feeding, the authors have this to say -
Although numerous studies have shown that breastfeeding of infants is superior to existing alternatives, these data suggest the possibility that, in extreme cases, for mothers with high levels of exposure to PCBs and/or other closely related toxicants that bioaccumulate in breast milk, lactational exposure of genetically at-risk infants may in fact not be in the infant’s best interest.
Notice the use of the words "possible", "extreme cases", "high levels of exposure", "genetically at-risk" followed by a "may not be in the infant's best interest". Slam dunk against breast feeding, right?

It would have been much more accurate to report that exposure to high levels of PCBs early in life may cause developmental problems but that wouldn't be a shocking as breast feeding causing autism, now would it?

Friday, July 24, 2009

Study Watch : Prenatal Airborne Polycyclic Aromatic Hydrocarbon Exposure and Child IQ at Age 5 Years

Photo by tedbassman (flickr)

In the August 2009 issue of Pediatrics there is a study showing that some forms of air pollution can adversely affect a child's IQ if they are exposed early and often enough.

Polycyclic aromatic hydrocarbons (PAHs) are a group of pollutants that are produced and released into the environment as a byproduct of burning fossil fuels, tobacco, and other such substances. These substances are known to cause cancer (carcinogenic), genetic mutations (mutagenic), and birth defects (teratogenic). Newborns and fetuses children are thought to be especially susceptible to this form of pollution.

This study looked at the relationship between prenatal/early postnatal exposure to airborne PAHs and intelligence in a group of children in New York City.

To that end, a group of pregnant women was recruited from select area of New York City between 1998 and 2003. These women were between 18 to 23 years old, non-smokers, non-drug users, and in good health.

To measure prenatal exposure to PAHs the air quality in the women’s home environment was sampled during the third trimester of the pregnancy. The air was analyzed to determine the level of PAHs – the range of values was from 0.49 ng/m3 to 34.48 ng/m3 with the mean being 2.26 ng/m3.

Since the level of air pollution in New York City is stable and does not vary seasonally this level of exposure was used as the exposure of the children to PAHs during early childhood as well.

When the children reached their fifth birthday, they were given the Wechsler Preschool and Primary Scale of Intelligence-Revised (WPPSI-R) to determine their IQ.

There were 249 children still participating in the study at age 5 who had enough data to be included in the results. The children were split into a low and high exposure group based on their mother's PAH exposure while pregnant. There were 140 children in the high exposure group (PAHs over 2.26 ng/m3) and 109 children in the low exposure group.

The data was adjusted for the mother's intelligence, the quality of the home environment, other exposures to PAHs (i.e. second hand smoke, dietary sources), as well as other factors.

The results indicate that the children in the high exposure group scored about 5 points lower on average on several measures of IQ than the low PAH group - this roughly translates to a 4% percent lower IQ.

To put it another way, chronic exposure to pollutants like these could very well negatively affect a child’s IQ in the same way that chronic exposure to low levels of lead does.

So what does this study have to do with autism? Well, the authors also included some of the other affects that PAHs are thought to have on fetuses and very young children :
  • Epigenetic changes
  • Lower immune competence
  • Metabolic and neurological functional problems
  • Decreased ability to detoxify chemicals
  • Decreased ability to repair DNA damage
  • Endocrine disruption
  • Oxidative stress
Any of these look familiar?

Thursday, July 23, 2009

Study Watch : The case for developmental neurotoxins contributing to a disease of neurodevelopment

Photo by BEN+_+ (flickr)

Earlier this year there was a study published in NeuroToxicology that looked at whether there was a relationship between the distance from Superfund sites and autism rates in Minnesota.

Ockham’s Razor and autism: The case for developmental neurotoxins contributing to a disease of neurodevelopment

This study was authored by Catherine Desoto, PhD who is somewhat famous (or infamous) in certain circles for finding a mistake in a published study about the relationship between mercury and autism. As a result of the mistake, the study in question went from showing no relation between mercury exposure and autism to showing a modest, but not statistically significant, relationship. See here for more details if you are interested.

This study has two major parts. In the first part the author attempts to make the case for a relationship between toxins in the environment and autism by combining recent research into a coherent theory. While this part is interesting and worth reading on its own there is no new data to back up the theories. As a result I am going to skip this part.

The main part of the study then looks for a relation between the rate of autism in a school district and the number of Superfund sites within a certain distance. For each of the 336 school districts in Minnesota that had over 104 students the rate of autism was calculated. Some of the districts with fewer students and higher number of autism cases were averaged in with the surrounding districts to prevent them from skewing the analysis.

The author hypothesized that school districts that had one or more Superfund site within a ten mile radius would have a higher rate of autism than those that did not.

The geographic center of each district was computed and the number of Superfund sites within a 10 mile radius of this center was calculated using specialized software.

There were 46 school districts that had one or more Superfund sides within a ten mile radius. For these districts the mean rate of autism was 1 in 92 students. For the rest of the districts the mean autism rate was 1 in 132. It is worth noting that both figures are higher than the CDC's recent estimate of 1 in 150.

To double check the results the author redid the comparison and looked at school districts that had a Superfund site within 20 miles - the 97 school districts the fell in range had a higher rate of autism as well.

So the data support the idea that there is a correlation between the rate of autism and the number of Superfund sites nearby.

Unfortunately, the correlation in this case does not mean that the Superfund sites cause autism (correlation vs causation) and the author acknowledges as much.

Some other potential problems are that there is no information about where the families lived during the pregnancy or whether the families moved into particular school districts because of the services offered by the district. The first fact would be important because it is thought that prenatal toxic exposures are more harmful and more likely to result in autism while the second could potentially skew the rate of autism in each district (i.e. better services attract more children with autism).

I think there is something to this idea and that there is a relationship between the toxic chemicals in the environment and autism but this study falls short of showing anything more than a superficial relationship.

This study was also written about earlier this year here and here.

Wednesday, July 22, 2009

Same person, different DNA?

Photo by mknowles (Flickr)

According to The Scientist a recent study is casting doubt on the assumption that all tissues in your body contain exactly the same DNA. Researchers found that the genetic material found in blood may differ from that in other tissues in the body.

The researchers in question were searching for the genes responsible for a fatal condition and found "that complementary DNA from diseased abdominal aortic tissue did not match genomic DNA from leukocytes in blood from the same patient."

Got that?

Needless to say this could cause problems for autism studies that rely exclusively on blood samples for genetic material, like say this one or this one or this one or any other study that relies heavily on data sets like the one provided by AGRE.

This doesn't mean that these studies are wrong per-se, it just means that they might not be looking at the complete picture. Maybe the problem with finding the genetic cause of autism is because we aren't looking in the right place?

Saturday, July 18, 2009

Breast Milk and a Leaky Gut

One of the more popular yet controversial treatments with autism is the gluten free/casein free diet. There are a large number of parents who try this diet with their children and many report good results. Yet mainstream medicine tends to laugh at the idea of a dietary change helping something like autism.

Very little research was been done that looks at how well the diet works and even less still has been done looking at the reasons that a diet might be effective. However, there are theories about why the diet works, one of which is called the leaky gut theory.

The basic idea in this theory is that a child's intestine is more permeable than it should be and lets all sorts of things into the body that should not be there. One of the things that can get through partially broken down parts of wheat and milk proteins (gluten and casein) and that can lead to a set of problems. But that is a subject for another day.

One of the things that I never fully understood was how or why this condition could develop in the first place - what could cause something like this and why can't the body repair itself.

I ran across a study the other day in Science Daily that might help answer this question. It seems that there is an ingredient in breast milk that helps protect and repair the gut in newborns -
The lining of a newborn's gut is particularly vulnerable to damage as it has never been exposed to food or drink. ...
The researchers found small amounts of PSTI in all the samples of breast milk they tested but it was seven times more concentrated in colostrum samples. The ingredient was not found in formula milk.
The researchers examined the effects of PSTI on human intestinal cells in the lab. When they inflicted damage to the cells they found that PSTI stimulated the cells to move across the damaged area forming a natural protective 'plaster'. They also found that PSTI could prevent further damage by stopping the cells of the intestine from self-destructing. Additional research suggests that PSTI could reduce damage by 75 per cent.
So it is possible that breastfeeding can help prevent and repair damage to a newborn's intestinal track which might be able to help prevent something like a leaky gut from getting started. This is obviously not something that "causes" autism but perhaps it can help mitigate some of the damage that autism can cause.

Please note that I am not saying that going the formula route is a terrible thing, after all, we did it with our twin daughters. The twins are on the GFCF diet and have had large improvements because of it.

But the funny thing is that our youngest daughter does not have the same dietary issues that her sisters did. She was breast feed and has never had the bowel issues, or eczema, or abnormalities in her blood work. So maybe there is something to this protect factor.

Just food for thought.

Friday, July 17, 2009

Autism Science Foundation : Brought to you from a basement

There is a new post up over at the Autism Science Foundation's (ASF) pseudo-official blog that highlights an "article" in the "highly prestigious Science Magazine" about Dr London leaving Autism Speaks.

I was curious what they had to say, so I clicked on the link in the post and was taken to a page on the ASF's site talking about Dr Eric London which contained the following -
Science Magazine has published a comprehensive story about Dr. London's resignation, titled "Resignations Highlight Disagreement on Vaccines in Autism Group", in its July 10, 2009 issue. Full text of the article is available courtesy of Science Magazine.
Notice the article has become a "comprehensive story".

I dutifully clicked on the link expecting a full length, comprehensive article that went into the details surrounding Dr London leaving Autism Speaks and the issues involved. But instead what I found was a very short "News of the Week" blurb that that did little more than give a terse summary of the basic facts of why Dr London left.

Disappointed, I scanned the clip to see if there was anything that I had not seen before and I am glad that I did. Tucked away in the final paragraph is this little nugget -
In April, Singer cofounded a new group called the Autism Science Foundation to fund research, in particular small pilot projects—but not on vaccines. Singer declines to say how much money the group has raised so far, but she vows to keep overhead low; the organization is currently working out of her basement.
So the Autism Science Foundation's HQ is in Allison Singer's basement - that explains a lot.

Thursday, July 9, 2009

Brian Deer thumbs his nose at the PCC

Some of the mystery surrounding the Press Complaints Commission (PCC) recent action in the matter of Brian Deer's reporting in the Times has been clarified. As I mentioned before it appeared that the PCC had requested that the Times remove the articles written by Brian Deer until the matter was resolved. The Times complied with the request and removed the articles.

But now they are back up with a weakly worded warning that "[t]his article is subject to an on-going Press Complaints Commission complaint". Or basically, the Times appeared to have decided to not obey the request from the PCC.

It has been suggested that it was Dr Wakefield's claim that the PCC "ordered" the Times to take down the articles was not accurate and that the PCC merely "asked" the PC to do so and this is given as the reason that the articles were reposted.

It seems that this claim is at least partly true. There is the original press release from Thoughtful House that does use the phrase "interim order" but now there are some further details about the case available. These details include what appears to be the text of the informal decision.

I suggest you go read the full e-mail trail included on that page to get the full context.

I am sure that this grouping of e-mails is not the entire story but there is one thing that I think can be cleared up - the Times was not "asked" to remove the stories, the PCC told them to. The exact wording is -
Given the ongoing nature of the dispute, the articles should be removed from the newspaper’s website until this matter has been concluded. This would not be an admission of any liability on the part of the newspaper.
That doesn't sound like "asking" to me which means that Dr Wakefield's claim that the PCC ordered the articles down is more or less true - the word ordered might be a little overstated but it certainly wasn't merely an informal suggestion.

If read further you get the impression that the reason the articles were reposted was that the Times and Brian Deer were n0t happy about Dr Wakefield publicly announcing the PCC's request/order -
In the light of the actions of Dr Wakefield and/or his representatives, and the inaccurate "spin" which has been put on the PCC request, my client feels that it is entirely inappropriate and prejudicial to keep the articles down. My client will therefore be reinstating the articles onto its website, but will be tagging them to make it clear that they are subject to a PCC complaint which is ongong.
I wouldn't be happy if I were them either. But that doesn't mean the Times should disobey the PCC just because taking down the articles makes them look bad.

Finally, if you look at the last e-mail in the chain you see Brian Deer writing directly to who I am assuming is a lawyer representing Dr Wakefield and almost gleefully talking about his articles being republished. He accuses Dr Wakefield of making "false claims", "misleading the public", and of being "dishonest". I have to wonder if he has looked in a mirror lately.

If I were Brian Deer's lawyer I think I would be telling him to shut up right about now and stop getting involved. But then again Mr Deer has a history of writing inappropriate things so his e-mail doesn't come as a shock.

Given the overall tone of Mr Deer's letter I think it is reasonable to say that he as a personal beef with Dr Wakefield that could very easily be affecting his objectivity and judgement in the matter.

It will be interesting to see what, if anything, the PCC does in response to the Times reposting the articles. I would be willing to bet that they will take no real action - I am not even sure that they have any action that they can take besides telling them to take it down again.

Time will tell.

Sunday, July 5, 2009

Synchronized Stimming

For those of you who don't know, two of my daughters who have autism are twins. More than that they are identical twins with all that brings with it.

Physically that are as close to being the same as you can get. They look very much alike, although it is possible to tell them apart if you know them. Their height and weight have stayed remarkably in line with there being at most a quarter inch difference in weight and few ounces in weight. Their teeth all came in at the same time and in the same order.

Mentally the story is the same - they have basically the same skill sets and abilities. While one twin might do something slightly before the other it is almost a sure bet that the other will be soon to follow.

However, their personalities are very different. Twin A is a free spirit while twin B is more refined and lady-like (and bloody stubborn too). They have different likes and dislikes as well as different ways of interacting with other people.

Unfortunately they are among the 80 to 90 percent of identical twins that share their autism. Interestingly enough, while the core communication deficits are the same, the outwards symptoms of autism and how they are expressed is very different. But this is a topic for another day.

They also had the beginnings of the bond that identical twins share, at least until they were a year old. Then autism came for a visit and disrupted the normal course of their development and the budding twin bond seemed to disappear.

To be honest we haven't been sure if it isn't still there in some form or another. They don't acknowledge or actively seek out each other as they did once upon a time but there have been little hints here and there that the bond might still exist.

Well, now we know that the bond still exists. How do we know? Simple, they are engaging in what can best be described as synchronized stimming.

Synchronized stimming, like synchronized swimming, is when they both do the same stim at the same time in perfect unison. So far we have seen spinning in a circle and intricate hand movements, all in perfect lock step. It isn't like they are able to talk about what they are going to do first or that one starts the stim and the other picks it up - they both start the same motion at the same time and do the same set of movements.

The only explanation that we have been able to come up with is that this is their twin bond trying to reassert itself in spite of their autism. While this isn't what we expected their bond to be like, we will take it.

It is nice to know that the bonds between twins can be stronger than autism.

Thursday, July 2, 2009

Wakefield and the Times

As reported at the Age of Autism site, there has been some small action in the matter of Brian Deer's reporting in Times. It was five months ago that Brian Deer's articles appeared in the Times online and four months ago that Dr Wakefield filed a complaint with the UK's Press Complaints Commission (PCC).

The commission has not yet ruled on the complaint but it just recently asked the Times to remove the articles in question from their web site, which they did.

As I said before, I did not expect the PCC to take any real action on the case and while the asking the Times to take down the articles for now is a good first step, it is a far cry from actually issuing a ruling in the case. The PCC's charter promises to "respond swiftly to your enquiries" and "deal with your complaint as quickly as possible ... in an average of 35 working days". So are only taking three times longer than they say they would.

OK, in all fairness, it seems like the majority of the time has been spent waiting for the Times to respond to the complaint - according to the Age of Autism, it took the Times over three months to respond

I cannot understand why this is moving so slowing. I would assume that Brian Deer would have all the facts needed to support his stories and that the fact checking department of the newspaper would have verified the story before it was printed. If this had happened then then the newspaper should have been able to submit them to the PCC and the complaint should be swiftly resolved.

But judging from the delay and the fact that the PCC has asked the Times to take down the stories I am guessing that he does not have the facts to back up his stories. Maybe it is time for the Times to retract the story and Mr Deer to apologize?

Wednesday, July 1, 2009

Its the chemicals (and forget what I just said)

Dr Harvy Karp has posted the third and final part of his series on vaccinations on Huffington Post. I wrote earlier about how the first two parts of the series regurgitated the same old tired lines about their being no link between vaccinations and autism.

In the final part of his series Dr Karp changes his tone and spends most of his time talking about endrocrine disrupting chemicals (EDCs) and how they might be related to autism. These chemicals include things such as BPA, phtlates, and flame retardants.

He believes that there is a "rising tide of evidence" that some or all of these chemicals could be "a possible poison to our children's developing brains". No studies have been done that have established a link but Dr Karp thinks that "our exposure to EDCs is no mere theoretical concern" and that "we urgently need more research to discover whether EDCs, or other chemicals, are linked to the worldwide rise in autism". One of the additional pieces of research that is just getting underway is the National Children's Study (NCS). Dr. Karp has this to say about this study -
The NCS may be our generation's best chance to solve the autism riddle. It is exactly the type of study needed to tease out the subtle relationships that may exist between autism and chemicals.
I can only say one thing - its about time.

This sort of approach is long overdue given how much more common autism is than 30 years ago and how little work has been done to look into environmental factors involved in autism. I have to commend Dr Karp for writing about something so important and taking a break from chanting the "its genetic" party line.

Now for the funny part of the article.

Tucked down at the bottom of the post Dr Karp listed three other areas that he believes need additional research. If you didn't read what I wrote about the two earlier parts of the series either go read that (link above) or, even better, the actual two articles.

Here are the three items he lists:
  1. the autism risk in vaccinated vs. unvaccinated kids
  2. the metabolism of vaccine ingredients (like aluminum, added to make shots work better)
  3. more accurate determinations of the true incidence of autism
So you got that? After spending two articles worth of writing to say that the questions surrounding autism and vaccines have already been answered he turns around and says that we really need more study after all. If he really thinks that then why didn't he say so in the first place?