I recognize that most science reporters are under a deadline. I also understand that sometimes a human interest story is interpreted as a science story (a sample of one is interesting and worth noting but not actually scientifically valid) but every once in a while I read reporting that is misleading and would have required about 20 minutes extra to be complete. It does not bring out the best in me.
There is a recent study that states that there is no link between celiac disease and autism. Sort of. But not exactly. What the study actually says is that the number of people with autism who also have a diagnosis of celiac disease is not meaningfully different than the number of people in the general population who also have a diagnosis of celiac disease.
OK people, does anyone else see a few obvious problems with this?
1) The study relies on people who already have an ASD to decide to get tested for a second lifestyle challenging disorder – If you know someone with a severely autistic child then you know someone who is pretty much at her limits. She is in no shape to seek out new problems to deal with. Especially if they involve anesthetizing a child who can become hysterical when he does not get grape jelly for lunch. I would entertain the possibility that these parents decided not to scope based on my highly unscientific survey of parents with autistic children who look at me like I have a second head when I suggest that they have the child tested for celiac disease. Then I often hear muttering like “as if I don’t already have enough to deal with, and besides all he eats is bread anyway”
2) The same study showed a spike in positive results for the blood test for CD in people with an ASD. As a matter of fact a 400% increase. So someone with an ASD was 4x as likely to have bloodwork that indicated CD even if he or she had a negative biopsy. Now here is where it gets weird. They decided, against EU protocol and against Mayo Clinic protocol, to change the definition of “a diagnosis of celiac disease” back to the old version. See now they know that if you fail the blood test and fail the gene test and you get well on a GF diet then you have CD and that the biopsy (which can be negative with dermatitis herpeteformis) is not perfect. But, by that definition, you get the result that gluten is impacting these kids. Since apparently the reporters don’t want that result, they just change the definition of a diagnosis to an older version and voila! new results. This, by the way, is how I got from a size 10 in 1988 to a size 4 now without actually losing a single pound. They just redefined the sizes and poof I am magically (not) thinner.
3) As much as I adore statistics and think that one can learn a lot from epidemiology, it is best to test a hypothesis with an actual randomized placebo controlled study. Oh look, one was actually done. Oh look, the study was halted midway because the autistic children who were not getting the gluten-free diet were doing so much worse that it seemed cruel to continue since they already had their answer.
Wanna see it? Here you go
You can read the full study from the celiac center at Columbia University that showed elevated blood reactions to gluten here
The abstract of the original Swedish study can be found here
And please, read the research. You can’t always trust what you read online…not even from me.