What Causes Autism and How is it Diagnosed?

1/21/2008

Autism is a disorder that puts a scare into parents, and all the misinformation floating around about just serves to up the fear factor. So here’s what we know so far.

What is autism?

Autism Spectrum Disorder (ASD) occurs in 1 in 150 children. It’s a complex multi-factorial developmental disorder that includes a wide range of behavior and learning problems varying from mild to severe. Differences in brain structure and development can cause significant problems with social interaction and communication as well as unusual behaviors and interests. Typically a child with autism is more interested in things or systems than he is in people or feelings. I say “he” because boys are four times more likely to be autistic than girls. Many children with ASD also have other issues, such as attention problems.

Is there an epidemic of autism?

The number of cases of autism does seem to be rising, and not all of that increase can be accounted for by the improvement in diagnostic guidelines or by the possible over-reporting in order to qualify for the more personalized educational resources available to children with diagnosed disabilities.

What is the cause of autism?

No one knows what causes autism, but theories abound. Because it appears is so many forms, it may even be that different things cause autism in different people. It is generally agreed that autism has its roots in the womb, as videos of babies later diagnosed with ASD show subtle signs and symptoms as early as a few months of age. What we do know is that autism is not caused by vaccines, with the possible exception of children with vulnerabilities in their immune system. It is also not caused by bad parenting--children are born with autism or the potential to develop it.

These factors may play a role:

Genes. Abnormalities on several specific genes related to brain development appear to be related to autistic behavior, but there may have to be something that turns these genes on or off before autism actually develops. It also may be that both parents have to carry those genes.
Hyper-masculinization of the brain. Autistics may have been exposed to abnormally high levels of testosterone in the womb that cause the systemizing parts of their brains to develop more in relation to the empathizing portions. There may be a genetic component here, too, as studies suggest autistic children often have good systemizers—engineers and others with very good attention to detail—on both sides of their families.
Environmental toxins. I believe that increased exposure to chemicals and heavy metals is at least partially responsible for the rising numbers of autistic children. Levels of exposure to methyl mercury—the kind present in pollution from waste incinerators and coal-fired power plants, not the kind that was used as a preservative in some vaccines—has been linked in several large recent studies with autism.
Exposure to viral or metabolic imbalances during pregnancy. Either of these may act as triggers to abnormal development of the brain.

Can autism be prevented?

Since the cause of autism hasn’t been found—and there may never be just one cause—we don’t really know how to prevent it. However, I urge all parents to minimize exposure to heavy metal and chemical exposures before, during, and after pregnancy. We devoted an entire chapter to this issue of environmental threats in our book, Healthy Child, Whole Child.

How do I know if my baby or child is autistic?

The period from 12-24 months is a very busy and sensitive period in the development of the brain and the time when clearer signs of autism generally emerge. However, the sooner a diagnosis of ASD is made, the better. There’s good evidence that intensive early work with a child with ASD can reduce learning, behavioral, physical, and emotional disability.

You and your child’s doctor should be looking for these red flags:

Failure to make eye contact at 3 months
No smiling at six months
No babbling, gesturing, or pointing at 12 months
No response to name at 12 months
No single words at 16 months
Loss of language or social milestones at any age

Other than the last, no single red flag should set off an alarm, but several at once or progressively mean you should raise the issue with your pediatrician and consider a referral to a developmental pediatrician for a full screening and diagnosis. The American Academy of Pediatrics is now suggesting that all pediatricians do an autism screening as a routine part of the 18-24-month well-child visit, but catching it sooner is definitely in your child’s best interests.

You can find excellent information about ASD at these websites: