(RxWiki News) The possible causes of autism are one of the great mysteries of medicine today. It is possible that certain health conditions during pregnancy might play a role in autism.
A recent study found a possible link between autism and a disease called lupus in mothers.
Lupus is an autoimmune disease in which the body's immune system mistakenly attacks part of itself.
Mothers with lupus were about twice as likely as mothers without lupus to have a child who was eventually diagnosed with autism, according to this study.
The medications the women took while pregnant did not appear to influence their children's risk of an autism diagnosis.
"Attend all prenatal appointments."
This study, led by Evelyne Vinet, MD, a professor in the Department of Rheumatology at McGill University Health Center in Montreal, Canada, aimed to find out whether mothers with lupus were more likely than other moms to have children with autism.
The researchers used data from the Offspring of Systemic Lupus Erythematosus mothers Registry, a group of 509 women with lupus who gave birth at least once in Quebec between 1989 and 2009.
For each woman with lupus in the group, the data set also included four women who did not have lupus but were the same age as the woman with lupus and who gave birth the same year she did. These 5,824 "matched" women without lupus were used as comparisons with the women who had lupus.
The researchers followed the women for an average of 9 years. The women were an average age of 30 at the time of follow-up.
The researchers then compared how many children born to the mothers with lupus had autism spectrum disorders compared to the children born to the mothers without lupus.
The researchers found that 1.4 percent of the children born to mothers with lupus had autism spectrum disorders.
Meanwhile, only 0.6 percent of the children born to mothers without lupus had autism spectrum disorders.
Interestingly, the average age of the children with autism when they received their diagnosis varied across the two groups.
Children with autism born to mothers with lupus were diagnosed with the disorder at an average age of 3.8 years old while children with autism born to mothers without lupus were an average 5.7 years old when diagnosed.
The researchers made calculations to find out how much more common autism was among children born to mothers with lupus after taking into account the mothers' personal and social characteristics, the child's sex, any pregnancy or delivery complications and the child's birth order.
The researchers found that children born to mothers with lupus had approximately 2.3-fold greater odds of being diagnosed with autism spectrum disorders than children born to mothers without lupus.
The researchers also examined more closely a smaller group of women in the larger group to see if medication usage during pregnancy made a difference in their children's risk for autism.
Among 1,925 children for whom the researchers had information about the mothers' medication use, only 18 had autism.
None of these children's mothers had taken antimalarials, antidepressants or immunosuppressant medications.
One child with autism born to a mom with lupus and one child with autism born to a mom without lupus had been exposed to corticosteroids and/or anticonvulsants while in the womb.
The researchers concluded that children born to mothers with lupus did have a higher risk of being diagnosed with autism than children born to mothers without lupus.
"Autism is a complicated diagnosis that likely has many different associated factors," said Sarah Wagner, MD, obstetrician and gynecologist at Loyola Outpatient Center in Maywood and Loyola Center for Health at Oakbrook Terrace.
"Those factors are being studied extensively. Understanding that maternal lupus may have an association with an increased risk for autism could be helpful for future study of the disease progression. We look forward to identifying more specific ways to help prevent autism, and data like this may help pave the way," Dr. Wagner told dailyRx News.
Glen Elliott, MD, PhD, a clinical professor at the Stanford University Department of Psychiatry and Behavioral Sciences, said the possible connection between autoimmune processes and autism has fascinated researchers for decades.
He said the main focus of this research has been abnormalities in the immune systems of autistic individuals themselves.
"These researchers suggest that at least one autoimmune disorder, lupus, in the mother may double the risk of autism in their offspring," he said.
"It is an intriguing finding that raises important questions such as what products are conveyed from mother to infant during pregnancy that might account for this increased risk and whether this is a general phenomenon common to all autoimmune disorders or specific to lupus," Dr. Elliott said.
"As those who read results such as this often know already, the absolute increase relatively small, but it would seem to open up promising new leads for further research," he said.
This study was presented October 26 at the American College of Rheumatology Annual Meeting in San Diego.
This study has not yet been published in a peer-reviewed journal, and its findings should be interpreted with caution.
Information on funding was unavailable, but the authors listed no possible conflicts of interest.