Autism has been linked to a mother’s inflammation during pregnancy, and to mother’s use of antiepileptic drug use, new studies show.
One new study suggests that maternal inflammation during early pregnancy may increased the risk of autism in children. The new findings, cataloged by the National Institute of Environmental Health Sciences, note that children in mothers with elevated C-reactive proteins. These proteins are markers of inflammation.
The risk of autism among children in the study was increased by 43 percent among mother with inflammation caused by elevated C-reactive protein (CRP) levels. The risk was further increased to 80 percent in mothers who were in the top 10th percentile of CRP. The findings, published in the journal Molecular Psychiatry, add to increasing evidence that an overactive immune response can “alter the development of the central nervous system in the fetus,” thereby causing autism, among other things.
Lead scientist in the study Alan Brown, M.D., had this to say: “Elevated CRP is a signal that the body is undergoing a response to inflammation from, for example, a viral or bacterial infection. The higher the level of CRP in the mother, the greater the risk of autism in the child.”
Brown cautioned, however, that the prevalence of inflammation during pregnancy is substantially higher than the prevalence of autism. In other words, every case of inflammation during pregnancy does not lead to autism in the baby.
“The vast majority of mothers with increased CRP levels will not give birth to children with autism,” Brown notes. “We don’t know enough yet to suggest routine testing of pregnant mothers for CRP for this reason alone; however, exercising precautionary measures to prevent infections during pregnancy may be of considerable value.”
In another new study, autism is also linked to exposure to the antiepileptic drug sodium valproate, often used to control seizures. Children whose mothers take the drug while pregnant are at a significantly increased risk of developing autism and other neurodevelopmental disorders. The small study, published online in the Journal of Neurology Neurosurgery and Psychiatry, bases its findings on children born to 528 pregnant women between 2000 and 2004.
Fewer than half of the mothers in the study had epilepsy, and all but 34 of them took antiepileptic drugs during their pregnancy. The others took a variety of other drugs to monitor their seizures. According to the study, the children’s physical and intellectual development was assessed at the ages of 12 months, three and six years. Information was also obtained from their mothers about whether they had had to consult specialists about their child’s behavior, development, educational progress or health.
Full information was available for 415 children. In all, 19 of these children had been diagnosed with a neurodevelopmental disorder by the age of six. Three of the children also had a physical abnormality. Of the 19 children, 12 had a form of autism. One was also diagnosed with attention deficit hyperactivity disorder. Three had ADHD alone, without autism.
These studies, in short, show that children whose mothers had epilepsy and took the anti-seizure medication antiepileptic drugs — 7.46 percent, compared with 1.8 percent whose mothers did not have epilepsy.
The risk, however, is not linked to epilepsy, but to the anti-seizure drug.
While other links to autism have been suggested, these new studies suggest that autism can be caused by inflammation during pregnancy, as well as use of antiepileptic drug use.
[Image via Shutterstock]