Growth Hormone in Boys with Autism

Connie and others, I recently came across this press release suggesting that boys with autism have higher levels of some growth-related hormones.

http://www.nih.gov/news/pr/jun2007/nichd-22.htm

Could you check it out? I would assume that they compensated for such drugs as Risperdal, but there is no mention of that in the press release.

Missbennett: I read the actual article in Clinical Endocrinology, and could find no mention of whether they took into account meds that have weight gain as a side effect (like Risperdal). The kids were between the ages of 4 and 8, so perhaps not many would be prescribed these meds yet, but I don't know that for sure.

I actually met one of the authors of this article at the IAN Research Conference held last week --so I will see if I can find out for you!

An update to my last post! Dr. Cynthia Molloy, one of the authors of the paper on "Elevated Levels of Growth-Related Hormones in Autism and ASDs" referred to above, has sent us an answer to Missbennett's question.

Missbennett had wondered if the researchers who found boys with ASDs were heavier had taken into account the fact that some meds given to treat symptoms of autism have weight gain as a side effect.

Dr. Molloy answered:

"In the analysis, we accounted for appetite stimulating medications such as Risperdal in two ways. First, within our case group, we compared children being treated with such meds to those who were not treated and found no differences between them on height, weight, or Body Mass Index (BMI). However, BMI was, on average, higher in children with autism than in the controls, so we included BMI as a co-variate in the analyses to be sure the case-control differences we were seeing were not just because the kids with autism were bigger."

So, the answer is YES. The researchers did take into account meds that can lead to weight gain in their analysis.

Connie (IAN Staff) wrote:

An update to my last post!
"In the analysis, we accounted for appetite stimulating medications such as Risperdal in two ways. First, within our case group, we compared children being treated with such meds to those who were not treated and found no differences between them on height, weight, or Body Mass Index (BMI). However, BMI was, on average, higher in children with autism than in the controls, so we included BMI as a co-variate in the analyses to be sure the case-control differences we were seeing were not just because the kids with autism were bigger."

So, the answer is YES. The researchers did take into account meds that can lead to weight gain in their analysis.

The study also supported the notion that autistic boys have larger head sizes than controls.

High BMI is also reported in ADHD as is large head size. Neither of these findings appear to be specific to autism but leads the research community into making links and associations that are not there.

References
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BMC Pediatr. 2005 Dec 21;5:48.
Prevalence of overweight in children and adolescents with attention deficit hyperactivity disorder and autism spectrum disorders: a chart review.

Curtin C, Bandini LG, Perrin EC, Tybor DJ, Must A.
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J Intellect Disabil Res. 1999 Aug;43 ( Pt 4):279-82.
Is megalencephaly specific to autism?
Ghaziuddin M, Zaccagnini J, Tsai L, Elardo S.

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Connie wrote
An update to my last post! Dr. Cynthia Molloy, one of the authors of the paper on "Elevated Levels of Growth-Related Hormones in Autism and ASDs" referred to above, has sent us an answer to Missbennett's question. ...So, the answer is YES. The researchers did take into account meds that can lead to weight gain in their analysis.

Thanks for that clarification, Connie. It is great to be able to hear back from the researchers -- and to know exactly what they did! Kudos to IAN!

Regarding RAJ's post,

Could you specify in the context of this study, which controls were incorrect and tell me what they should have used in order to show what you surmised, that is, that these findings are not specific to autism and are not accurate conclusions to be drawn here. I would really appreciate you taking a moment to answer that!

missbennet wrote:

Could you specify in the context of this study, which controls were incorrect and tell me what they should have used in order to show what you surmised, that is, that these findings are not specific to autism and are not accurate conclusions to be drawn here. I would really appreciate you taking a moment to answer that!

The NIH used randomly selected normal controls. The correct controls would be to use other handicapping conditions to see if a finding is specific to autism. The Michigan study found that autism and ADHD both have 'large heads' in a small subgroup and found that autistic kids with 'large heads' have a higher rate of 'hyperactivity' and 'impulsiveness' than autistic kids who do not have 'large heads'.

Here is the abstract comparing Autistic kids and ADHD kids with respect to 'head size':

Several recent reports have described the presence of increased head circumference (megalencephaly) in patients with autism. Although some studies have described reports of megalencephaly in other disorders such as schizophrenia in adults, few such studies have been performed in children and adolescents. In the present study, the authors compared 20 subjects with autism/ pervasive developmental disorder (DSM-IV; all males; mean age = 10.9 years) with 20 controls with attention deficit hyperactivity disorder (DSM-IV; all males; mean age = 11.1 years). Four subjects and five controls had evidence of megalencephaly. In addition to their core symptoms, the autistic subjects with megalencephaly were hyperactive and impulsive. These findings suggest that megalencephaly may not be specific to autism, and when present, it may index the presence of additional symptoms such as hyperactivity and impulsivity.

I do disagree with you, RAJ, that the control group should be a group with "other handicapping conditions". That group would then cease to be a control group, no? I mean to say that ideally, a control group should be as close as is possible, a baseline.

I think that a better way of getting at the root of this question would be to compare similar studies targetting other disordered populations (also using random, normal control groups) with this autism study.

Also, the study measured levels of certain growth hormones, not just BMI, so to me, it does not appear to be comparable to the ADHD study you provided. It is sort of like comparing apples to oranges.

However, I think, as always, you raise a valuable point as to whether this is the best use of research resources. Your posts make me think and question, so for that, I appreciate your viewpoints.