I see that my friend Steve Edelson, who took over the ARI after Bernie Rimland passed away is promoting secretin as an effective autism treatment over at http://www.ageofautism.com/. I have met Steve at a couple of the national ASA conferences. He was very nice to me and I like him personally, but I still question a lot of positions and treatments that ARI proposes. He bills secretin as one of the most promising autism treatments ever.
Secretin is a hormone that appears in the GI tract and is involved in aiding the process of digestion. It also appears in the brain. As Steve points out, there are studies showing that it appears in parts of the cerebellum and hippocampus and limbic system, areas that have been implicated in the etiology of autism.
Steve cites the initial anecdotal evidence of the effectiveness of secretin in this boy named Parker Beck, and the uncontrolled subjective observations of this boy's improvement. He then mentions a pharmaceutical company which got the rights to the patent of synthetic secretin, which was cheaper to make than the secretin which was extracted from the duodenum of pigs. For some reason, I don't understand, Steve implies that somehow the molecules of the secretin extracted from pigs is somehow different from the kind that can be synthesized in a lab. Maybe someone with more erudition in chemistry than I have can explain to me why the organic secretin would be vastly different than the synthetic variety in its alleged effects on autism. The drug company did some studies using these two different subjective autism rating scales and determined that secretin was not effective overall. Yet when a subset of high functioning autistics were assessed it was found that they had made statistically significant improvements on one of the ratings but not on the other. Steve goes on to define the statistically significant changes on only one but not both of the rating scales as having "improved dramatically".
He then goes on to make the claim that the owner of the pharmaceutical company had a conference telephone call with the company's stockholders claiming that several of the children in the experimental group went from autistic to normal (italics added). How 'normal' was assessed in this alleged phone call I have no idea. As far as I can tell the only measures used in this drug company's study were two autism rating scales. No standardized tests were used to assess the children after the porcine (from pigs) secretin was used, no reports of scholastic placement, and certainly no adult outcomes, how they fared in jobs, heterosexual relations, etc.
Finally Steve tries to show the need for further research on secretin. He cites a study done by Janet Kern in Texas who found that about a quarter of the autistic children in an experimental group who received the porcine (non-synthetic) form of secretin improved in some of their behaviors, in terms of throwing less tantrums and having an improved vocabulary. The only children in Kern's study for whom the secretin seemed to be effective were those with GI problems. Secretin was no different than a placebo for autistic children without GI problems.
It is interesting to note that Kern in a more recent study on heavy metals in the etiology of autism has collaborated with ARI board member James Adams, so it would appear she has some sort of connection to Steve Edelson himself.
Though Steve calls for more research to be done on secretin he neglects to address in his piece the fact that numerous controlled studies have been done showing secretin to be ineffective as an autism treatment.
In a study done by Sandler, et. al in the New England Journal of Medicine a comparison was made between 28 children with autism injected with the synthetic version of secretin and 28 controls. The authors noted no difference between the two groups.
Another study published by Chez in the annals of neurology also showed that secretin was ineffective as an autism treatment.
A review showing 15 studies showing secretin to be an ineffective treatment are reviewed here: http://www.ncbi.nlm.nih.gov/pubmed/15590241?dopt=Abstract
So far as I know, besides Kern's study, the only other published report of secretin being an effective autism treatment was produced by someone named Hvorth published in an obscure publication entitled the journal for the association of academic minority physicians. This study was an uncontrolled study involving only three children.
Steve Edelson really fails to address or mention or critique any of these studies that refute the evidence that secretin may be a worthwhile autism treatment and that further research into secretin as one of the most promising autism treatments should be pursued. As far as I can tell his only criticism of these studies is that they used synthetic secretin rather than the porcine secretin that was extracted from pig intestines. He does not mention why the porcine version would be more effective than the synthetic version or chemically what the difference is. Even in Kern's porcine secretin study, a very small minority of the children improved and only those with GI problems. Out of all the persons with autism in the world, what percentage have these GI problems. Steve does not address this point. Another possible reason that synthetic secretin is used rather than the porcine version is that introducing a substance from a pig could cause the human immune system to have an adverse reaction. Though I will admit I am not an expert in this, it seems to me that it would make sense that because the human immune system would treat this as some sort of foreign agent, treatment with the pig secretin could be harmful to autistic children. Is it possible that after reading this article on the age of autism web page, some parent whose autistic child does not have a GI problem may end up seeking secretin as a treatment. Parents of autistic children are desperate people and easily exploited, so this does present a problem for me. There seems to me no evidence that secretin is a legitimate treatment for autism.