Autism research: infertility treatment link, no benefit of special diet Posted by TIFFANY O'CALLAGHAN Thursday, May 20, 2010 at 6:48 pm.
Autism researchers from around the world are meeting this week (May 20, 2010) in Philadelphia at the annual conference of the International Society for Autism Research, and have presented studies investigating everything from the impact of an autistic child on the strength of his or her parents' marriage, to the merits of popular gluten-free, casein-free diets for children with autism spectrum disorders and even a possible link between fertility treatments and increased risk for autism.
As Claudia Wallis reports for TIME, two studies presented this week at the autism research conference suggest a correlation between fertility drugs often used by couples struggling to conceive and a slightly elevated risk for autism in children.
The researchers say that future research is necessary to confirm and expand on the initial findings and to rule out other potential confounding factors, but that the initial results imply a link between use of fertility drugs such as Clomid and a slightly higher risk for autism.
Yet both the study authors and Wallis are careful to note the emphasis on slightly. As Wallis writes: "Treatment-related risk appears to be small: among women whose average age was 35 when they had their first child, there was a 4% risk of having a child with autism for those who had taken fertility drugs, compared with 2% for those with no drug exposure. The increase in risk was even smaller among a younger subset of women."
Meanwhile, in a small study analyzing the effect of gluten-free and casein-free diets on autism symptoms — the special diet has been widely embraced in the autism community and praised by controversial autism activist Jenny McCarthy — researchers from the University of Rochester suggest that it actually provides no substantial benefit. (Gluten is a protein found in grains such as wheat and barley; casein is a protein found in dairy products.)
For the study, researchers followed 14 children with autism between the ages of 2½ and 5 ½ for 18 months. Families were instructed to adhere to strict gluten-free and casein-free diets, and researchers took painstaking efforts to ensure that participants received sufficient vitamin D, calcium and other nutrients, and screened all children for Celiac's disease, food allergies and iron deficiency.
After four weeks on the strict diet, one of four foods was introduced — containing small amounts of either gluten, casein, both or neither (placebo). All of the new foods were given to the children for snack, and carefully designed to look and taste exactly the same. The researchers found that, after children were given snacks containing gluten or casein, there was little noticeable change in behavior, and what incremental changes they did see were so small as to be attributable to coincidence.
As Dr. Susan Hyman, lead author of the study and associate professor of Pediatrics at Golisano Children's Hospital at the University of Rochester Medical Center, summarized in a statment on the findings: "It would have been wonderful for children with autism and their families if we found that the GFCF diet could really help, but this small study didn't show significant benefits."
Researchers say that future investigation of the influence of diet on autism symptoms is essential, and say that, in spite of the lack of impact shown in this study, for autistic children who also have gastrointestinal disorders or certain food allergies, the diet could yield significant benefits.
Another study released this week at the conference on autism research found that, in spite of the popularly touted statistic that 80% of married couples who have an autistic child face divorce, the majority of children with autism are in families where both biological or adoptive parents are still together.
On May 20, 2010, researchers from the Harvard School of Public Health presented their findings from a study exploring the possible relationship between the use of fertility drugs and autism spectrum disorder (ASD). The scientists reported to attendees at the International Meeting for Autism Research in Philadelphia that women who used fertility drugs to get pregnant had almost double the risk of having a child with ASD verses nonusers. The drugs studied included Clomid (clomiphene citrate) and Pergonal (gonadotropin).
Some have expressed skepticism about the study. However, although its value cannot be fully assessed until it appears in a peer-reviewed journal, there are several factors that argue in favor of its merits. In an effort to rule out other causes, Dr. Lyall and her colleagues made an “adjustment for pregnancy complications, maternal age, and other possible risk factors,” before making a determination that use of fertility drugs represented a 91% increased risk. This was at a highly significant statistical level – namely, the odds that their data did not occur by chance were 993 out of 1,000 (P=0.007). They also determined that a history of infertility – exclusive of fertility drugs – was not significantly associated with ASD, and that the “odds ratio for autism spectrum disorder increased with the number of reports of use of ovulation inducing drugs” (P=0.008).
This recent study is part of a growing body of research that strengthens the argument that Clomid and other fertility drugs are a cause of ASD via their ability to deny cholesterol to a developing embryo shortly after conception. About 58% of ASD children have low total cholesterol (<160 mg/dL) and about 19% have extremely low total cholesterol (<100 mg/dL). The average level for children is about 165 mg/dL. It has also been observed that a high percentage of children (71-86%) born with Smith-Lemli-Opitz syndrome (SLOS), in addition to a wide array of birth defects are also born with ASD. Infants with SLOS are born with a defective enzyme that impairs the body’s ability to convert a precursor (7-dehydrocholesterol) to cholesterol. Cholesterol is essential for growth of the myelin membranes that cover the brain and abnormalities in the myelin sheath are believed to be a contributing cause of ASD. Many experts thus believe that low cholesterol during early embryonic development is one of the causes of ASD.
Clomid has a long half-life and is present during the embryonic period (first 8 weeks) even when taken before conception. Studies have shown it to be biologically active for up to 54 days after ingestion and that it can accumulate over successive cycles of treatment. As mentioned, in the Harvard study they found that the longer the use of fertility drugs, the higher the risk of developing ASD. A critically important fact – and one not known by most physicians prescribing the drug – is that Clomid is a cholesterol inhibitor and impairs its production by acting upon enzymes in the body similar to Lipitor and other statin drugs. Its chemical structure is also similar to the cholesterol-reducing drug, Triparanol, which was briefly available during the 1960s. Animal studies have shown that Clomid and Triparanol both act on the same enzyme and affect developing organs in a similar way, with Triparanol being slightly more potent.
Pergonal (also known as human menopausal gonadotropin or hMG) likewise reduces cholesterol, but by way of a different mechanism. Namely, it suppresses cholesterol levels in early pregnancy via its ability to elevate estrogen production. Studies have established that following hyperstimulation of the ovaries by Pergonal, the resulting elevated estrogen during the luteal (post-ovulation) phase of the cycle suppresses the level of total cholesterol. In fact, there is an inverse correlation between concentrations of estrogen and the level of total cholesterol – the higher the level of estrogen, the lower the concentration of total cholesterol.
The GOOD NEWS is that many ASD children with low cholesterol, treated with cholesterol supplementation, have shown dramatic improvement. Scientists at Johns Hopkins University Medical Center, led by Dr. Richard Kelley, have shown such treatment resulting in improved mobility, verbalization, growth, behavior, sociability and alertness. Better yet, once we have a full understanding about one of the causes of ASD, some day in the future we might be in a position to eliminate that cause. As I postulated over two years ago, maintaining an optimum level of cholesterol throughout pregnancy could likely eliminate many cases of birth defects and autism spectrum disorder. www.terencemix.com.
Posted by: Terence Mix | October 03, 2010 at 09:16 AM