AUTISM AND PREECLAMPSIA LINK: NEW STUDY

Dec 9, 2014

Preeclampsia is a condition that appears during pregnancy and is characterized by high blood pressure and protein in the urine. Now, in a new study, researchers have found that children with autism spectrum disorder were more than twice as likely to be born to mothers with preeclampsia during pregnancy, suggesting a link between the two.

The researchers, from the University of California-Davis' MIND Institute, published their results in the journal JAMA Pediatrics. They also found that the likelihood of a diagnosis for autism spectrum disorder (ASD) increased further if the mother experienced more severe disease.

Preeclampsia typically occurs during middle to late pregnancy and up to 6 weeks after delivery, though it can sometimes appear earlier than 20 weeks. Symptoms for the condition include swelling, sudden weight gain, headaches and changes in vision.

In the US, preeclampsia affects 3-5% of pregnant women, but among women who have had it, around 20-40% of their daughters and 11-37% of their sisters will also get the disorder, according to the World Health Organization (WHO). 

Preeclampsia accounts for around 40-60% of maternal deaths in developing countries, and it can develop into eclampsia, a life-threatening condition often accompanied by seizures.

According to Cheryl Walker, senior author and researcher from the MIND Institute, preeclampsia can affect the developing brain in several ways. For example, limited nutrients and oxygen can cause oxidative stress, which encourages the release of proteins into the maternal bloodstream in an attempt to improve circulation.

The latest study involved over 1,000 children, between 2 and 3 years old, who were part of the Childhood Risks of Autism from Genetics and the Environment (CHARGE) Study in Northern California.
Though preeclampsia has previously been studied as an autism risk factor, the researchers say previous research has been inconsistent.
However, theirs is a population-based, case-controlled study that investigates not only links between autism and preeclampsia, but also whether autism risk is associated with preeclampsia severity.
In more than 500 male and female children who were diagnosed with autism, 200 were diagnosed with development delay and 350 were developing typically. All of the mothers of these children had confirmed preeclampsia.

Results showed that mothers of children who were diagnosed with autism were over twice as likely to have had preeclampsia during pregnancy.

Furthermore, mothers of autistic children or those with developmental delay were more likely to have had placental insufficiency, severe preeclampsia or both, compared with the mothers of children who developed typically.

Walker and her team also found that children with autism whose mothers had preeclampsia were more likely to have lower cognitive functioning. Additionally, they observed a correlation between preeclampsia and developmental delay without autism. "The level of detail obtained by the CHARGE Study on predictors, confounders and outcomes enabled a comprehensive exploration of this topic. While single studies cannot establish causality, the cumulative evidence supports efforts to reduce preeclampsia and diminish severity, to improve neonatal outcomes."

PESTICIDE EXPOSURE DURING PREGNANCY AND AUTISM RISK

June 26, 2014 APA

During pregnancy, the exposure to pesticides significantly increases the risk of having a child with an autism disorder. According to a US study that was published in "Environmental Health Perspectives", this leads to a two-thirds increased risk.

Scientists from the University of California, Davis, compared the domiciles of 1,000 mothers of two to five year-olds with autism, developmental delays or normal development with local data on pesticide application.

During their pregnancy, one third of the participants lived close to sites where pesticides were applied - within a distance of 1.25 to 1.75 kilometres. "What we saw were several classes of pesticides more commonly applied near residences of mothers whose children developed autism or had delayed cognitive or other skills", said study leader Irva Hertz-Picciotto. ́

The developing foetal brain may respond to the toxins much more sensitively than that of adults, said the physicians. It was assumed that pesticides distort the structural development and neuronal signalling pathways. Whether or not certain groups of women are more vulnerable to these toxins still needs to be researched. But it was already clear that pregnant women should avoid contact with these chemicals, the researchers emphasised.

ANTIDEPRESSANTS AND AUTISM

Balancing Antidepressants' Risks during Pregnancy

Antidepressants during pregnancy and autism may be linked but so may mood disorders

April 13, 2014

Taking antidepressants during pregnancy has always involved a balancing of possible benefits and risks. But so does skipping the medication when a mom has depression.

A recent study looked at whether taking antidepressants during pregnancy might increase the risk of autism or developmental delays in a mother's child.

The researchers found that there was an increased risk for autism with SSRIs during pregnancy, but there was a similar increased risk if the mothers had anxiety or depression.

It's not clear whether the higher odds of autism and developmental delays were due to the antidepressants or due to the mother's mental health condition or another reason.

"Discuss your medications with your OB/GYN."

This study, led by Rebecca Harrington, PhD, MPH, of the Department of Epidemiology at Johns Hopkins Bloomberg School of Public Health, looked at whether antidepressants taken during pregnancy could contribute to a risk for developmental disorders in the baby.

Specifically, the authors were studying antidepressants in the drug class known as selective serotonin reuptake inhibitors, or SSRIs.

The researchers compared 966 pairs of mothers and children, investigating the child's developmental disorder status, the mothers' use of antidepressants during pregnancy, the mothers' mental health history and the socioeconomic of the families.

Among these pairs, 492 children had an autism spectrum disorder, 154 children had delayed development, and 320 children had typical development.

Among the mothers of children with typical development, 3.4 percent had taken SSRIs during pregnancy.

Among the mothers of the other children, 5.9 percent of the mothers of children with autism, and 5.2 percent of the mothers with developmentally delayed children had taken SSRIs during pregnancy.

Boys, who are already at higher risk for autism diagnoses based on past research, had almost three times greater odds of an autism spectrum disorder if their mothers took SSRIs at any point during pregnancy than if their mothers did not.

If their mothers took SSRIs during their first trimester of pregnancy, boys had 3.2 times greater odds of an autism diagnosis.

Similarly, boys had about 3.4 times greater odds of having developmental delays if their mothers had taken SSRIs at any point during pregnancy.

If the mothers took the antidepressants during their last trimester, the boys' odds of developmental delays increased even more — to five times the odds of children whose mothers did not take SSRIs in pregnancy.

However, when the researchers looked at mothers who had an anxiety or mood disorder, they found similar rates of autism and developmental delays among the children.

Therefore, even though the study found an increase in odds for autism or developmental delays among mothers taking SSRIs in pregnancy, this increased risk could have actually been due to the mental health conditions that led the mothers to take the medications.

If mothers with anxiety or mood disorders, such as depression or bipolar disorder , have children with similar risks for developmental disorders as mothers taking SSRIs, then the risk may be more related to the underlying condition than the medication.

"Because maternal depression itself carries risks for the fetus, the benefits of prenatal SSRI use should be carefully weighed against potential harms," the researchers wrote.

This study was published April 14 in the journal Pediatrics. The research was funded by the National Institute on Environmental Health Sciences, the MIND Institute and Autism Speaks. The authors reported no potential conflicts of interest

Medications: 

Celexa Fluoxetine Lexapro Prozac Zoloft

Reviewed by: 

Robert Carlson, M.D

Beth Bolt, RPh

Review Date: 

April 13, 2014