A new study adds a twist to the pronounced ways that autism affects girls and boys differently. While boys are four times more likely to develop autism, when girls do, they’re more likely to also have seizures that don’t respond to epilepsy medications. Epilepsy, which affects up to a third of all people with autism, involves recurrent seizures that may or may not be obvious to observers.
“While many researchers have looked at differences between boys and girls with autism, this study is the first to focus so closely on differences in a medical condition that commonly occurs with autism,” comments developmental pediatrician Paul Wang, Autism Speaks head of medical research. “The findings underscore the importance of thoroughly evaluating for epilepsy whenever a child with autism shows behaviors that might indicate seizures.” These tip-off signs often include unexplained staring, lack of responsiveness and even repetitive motions – all behaviors that are frequently dismissed as part of a child’s autism. (Dr. Wang was not involved in the study.)
The new research, led by neuroscientist Karen Blackmon, of New York University Medical Center, investigated a previously noted difference between autism’s 4-to-1 male/female ratio and the tighter 3-to-1 male/female ratio for autism with epilepsy.
“This suggests that whatever protects women from autism does not shield them from epilepsy,” Dr. Blackmon says.
To investigate further, her team looked at differences in autism symptoms and seizure frequency and severity in a group of 130 children and young adults initially diagnosed with autism and subsequently diagnosed with epilepsy.
Overall, they found that the girls and young women had milder autism symptoms than did the boys and young men. But just the opposite was true in terms of their epilepsy. The females – even those with relatively mild autism symptoms – were more likely to have epilepsy that didn’t respond to the medicines typically used to prevent seizures.
Nearly half of these girls and women had failed to respond to at least two commonly used epilepsy drugs. By contrast, this was true of just a quarter of the boys and men in the study.
The researchers urged greater attention to girls and women with autism and epilepsy. In particular, they recommended that specialists use a full battery of genetic and brain imaging tests in addition to the electroencephalogram (EEG) testing traditionally used to identify epilepsy. This information may provide important information for better characterizing and managing seizures in girls and women with autism, they write.
In addition, doctors should be prepared to try multiple medications to find one that works well.
“All children with autism should be thoroughly evaluated for possible medical co-morbidities including epilepsy,” Dr. Wang concludes. “And future research on the causes and treatment of autism need to take these co-morbidities into account.”
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