Controversies

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Controversial Alternative Therapies

Hypothesis

There are many controversial and unsubstantiated theories of causation of ASDs and ineffective treatments in children with autism. Patients with serious levels of deficits and limited success with evidenced based treatments are particularly vulnerable to the placebo effect and thus more likely to falsely be persuaded that these treatments work. Below are some popular hypothesis which are unsubstantiated.

Chelation Therapy

Supporters of Chelation Therapy claim that autism stems from an excess in mercury and other metals in the body. In particular, they believe that the inclusion of mercury containing thimerosal in certain vaccines leads to an excess of mercury in the body which causes neurologic damage and subsequently autism. Thimerosal is included in vaccines to protect multiple-dose virals from bacterial and fungal contamination. '

Why this is unlikely No children with autism have been reported to have an elevated mercury levels or an excess of mercury in hair, urine, or blood through laboratory tests. Additionally, the clinical signs and symptoms of mercury-induced neurologic damage and the neuropatholgic changes associated with mercury exposure are NOT the same as the clinical signs and symptoms of autism. Furthermore, population based studies show that the risk of autism in children given thimerosal containing vaccines are the same as children given vaccines without thimerosal. Futhermore, in 1992 thimerosal was removed from childhood vaccines in Denmark, but the occurrence of autism has continued to rise in Denmark. If vaccines containing thimerosal caused autism, we would expect a drop in cases of ASD. Moreover, even IF thimerosal was related to the incidence of autism, there is no evidence that chelation therapy improves heavy metal toxicity.

Dangers There is a risk of renal and hepatic toxic adverse effects for children undergoing chelation therapy.

Measles, Mumps, Rubella vaccine (MMR)

Advocates of this hypothesis say that the MMR vaccine produces enterocolitis, or inflammation of the intestines, thereby causing a "leaky gut" which allows for increased absorption of peptides that work like endogenous opiods on the brain to produce autistic symptoms in a child.

Why this is unlikely Large studies on the distribution and control of diseases show that there is no association between the MMR vaccine and autism. Additionally, even though Japan has withdrawn the MMR vaccine, the occurrence of autism has still continued to increase.

Celiac Disease Variants, yeast overgrowth,fungal overgrowth and immunologic abnormalities

In these theories, opioidlike peptides that come from gluten and casein are absorbed through a "leaky gut" and cause symptoms of autism in the child. In this therapy, children with autism are given strict gluten and casein free diets to stop the absorption of opioidlike peptides.

Why this is unlikely According to studies, children with autism do not have an increased rate of celiac disease and do not have excessive amounts of opioidlike compounds in their urine, as would be expected if children with ASD were absorbing abnormal amounts of opioidlike peptides.Fungal overgrowth has not been seen in children with autism.

Although it is highly unlikely that gluten and casein in diet causes ASD, children with ASD do report gastrointestinal issues such as cramping or bloating more frequently than the typically developing population. However, most studies that attempt to validate a gluten and casein free diet are scientifically faulty in design. The only study where a randomized double-blind clinical trial of GFCF diet in children with autism was conducted showed no correlation between GFCF diet and improvement in ASD.2 Some researchers hypothesize that any improvements in ASD symptoms from being on a GFCF diet may be helpful because uncomfortable or irritable children are, naturally, more difficult to teach because they are distracted by their own discomfort. It is not known why children with ASD experience GI issues at a higher rate than the typically developing population.

Dangers Antifungal medications for the fungal overgrowth hypothesis have been shown to not improve autistic behavior. These drugs are also associated with liver toxicity, anemia, diarrhea, and exfoliative dermatitis. There have been reports of children who are under a GFCF diet experiencing bone loss, so clinicians should closely monitor their nutritional status. Additionally, ASD children may already have a very limited food repertoire which may make it impossible to implement a GFCF diet without seriously compromising their nutritional health.2

Difficulties It can be difficult to completely eliminate gluten and casein from the child's diet because the parent would need to coordinate the child's nutrition with other caretakers to ensure that the dietary restrictions are maintained when the child is in the care of another. Parents should keep daily records of food intake and behavioral changes to see if there is any behavioral improvements over time. In addition, gluten and casein free foods are often more expensive and time consuming to prepare.2

Autoimmune Disorder

It has been hypothesized that autism is an autoimmune disorder. However, treatment with intravenous immunoglobulins has not been proved to be effective.


  • References

1. Barbaresi et. al. Autism: A Review of the State of the Science for Pediatric Primary Health Care Clinicians. Arch Pediatr adolesc med/Vol. 160, Nov 2006. pg. 1171

2. Elder, J.H. The gluten-free, casein-free diet in autism: an overview with clinical implications. Nutr Clin Pract. 2008 Dec-2009 Jan;23(6):583-8. PMID 19033217

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