The most common autoimmune disorders include type 1 diabetes, ulcerative colitis, celiac and Crohn’s disease, psoriasis, multiple sclerosis, and rheumatoid arthritis, to name a few.
“Autoimmune diseases are disorders in which the immune system‘ incorrectly attacks the body, ’” said study author Timothy Nielsen, a research officer and doctoral student at Westmead Clinical School Children’s Hospital of the University of Sydney. The study was published Tuesday in JAMA Pediatrics.
The attack can lead to a “multi-organ” disorder like lupus or an “organ-specific” disorder like autoimmune thyroid disease (Hashimoto’s thyroiditis or Graves ’disease), Nielsen said in an email.
Nielsen said neurodevelopmental disorders such as ADHD, learning disabilities and autism are caused by alterations in fetal brain development during pregnancy. Previous research has linked autoimmune disorders in mothers with autism, obsessive-compulsive disorder and tics or Tourette syndrome in children, he said, but this is one of the first studies to examine its role in ADHD.
“I hope these findings don’t stress women with autoimmune conditions too much,” said developing pediatrician Dr. Jenny Radesky, assistant professor of pediatrics at CS Mott Children’s Hospital in Michigan Medicine, who did not participate in the study.
“I treat a lot of kids with ADHD, and those findings don’t change the way we manage them,” Radesky said. “While kids with ADHD can be a handful, I love their small, curious minds and their unique ways of seeing things.
“Mothers with autoimmune disease may work to have optimal control of their condition during pregnancy, but autoimmune disease is not like smoking during pregnancy (another risk factor for ADHD) that mothers have control over more direct, ”he added.
Large longitudinal study
The study followed more than 63,000 children born outright between July 1, 2000 and December 31, 2010 in New South Wales, Australia. Nielsen and his team identified 12,610 mothers with at least one of 35 common autoimmune disorders. Each of the pregnant women had a diagnostic code for an autoimmune disorder in their related hospitalization records.
A child was determined to have ADHD if there was a hospital diagnosis of ADHD or a record of a prescribed or stimulant-filled prescription.
All 12,610 descendants who were diagnosed with ADHD older than 3 years were included in the study and then related to four children of the same age with mothers without autoimmune disorders. The two groups of children were followed until the end of 2014.
The study also conducted a meta-analysis of existing research on the topic.
Combined, the results have shown that the diagnosis of any autoimmune disease, type 1 diabetes, rheumatic fever, or rheumatic carditis (inflammation of the heart muscle), psoriasis, and hyperthyroidism were associated with an increased risk of ADHD in the child at later ages.
Autoimmune disorders and inflammation
It is not yet known exactly how a mother’s autoimmune disorder can affect her baby. The researchers hypothesize that maternal autoantibodies (those that attack the mother’s body) cross through the placenta. Inflammatory molecules could do the same.
Once there, chronic inflammation could alter fetal brain development, possibly affecting the innate immune cells of the developing baby’s brain, according to the study. Or perhaps inflammation alters epigenetic markers (the chemicals that activate or deactivate genes) into key fetal neurodevelopmental genes.
Another theory, according to the study, is that inflammation affects the formation and function of synapses in the baby’s developing brain. Synapses are small pockets of space between two cells that allow cells to pass messages and communicate.
“These changes can lead directly to ADHD symptoms or can make the child more vulnerable to environmental risk factors,” Nielsen said.
Previous research has found that women with autoimmune diseases that are poorly controlled by drugs or other treatments could be a risk factor for poor pregnancy outcomes, such as failure of proper growth and premature birth, Nielsen said. .
“Our team is currently working on research into the causal mechanisms underlying the association between autoimmune diseases and ADHD,” he said, which may shed light on whether the “severity of the disease, symptoms, medication use, or other inflammatory factors modify this risk of ADHD “.
Knowledge is power
A pregnant mother who has an autoimmune disorder is just one of many risk factors for any childhood neurodevelopmental disorder, Nielsen stressed, “but understanding the risk and expression of the disease is essential if we are to prevent and treat the disease.”
Having the knowledge of this partnership can empower both women and their health care providers to “emphasize the importance of high-quality multidisciplinary care to manage autoimmune conditions before and during pregnancy,” Nielsen said. .
“This includes good pre-conception care and possibly avoiding pregnancy when disease activity is not well controlled,” she said.
After that, it is not anyone’s fault that a child develops a disorder based on the medical condition of the parents, experts emphasize.
“Sometimes parents will persevere in their guilt for a child’s ADHD to be‘ their fault ’,” said developing pediatrician Radesky.
“When that happens, I try to redirect their mental energy to understand their child’s unique mix of strengths and challenges, why the child behaves the way he does, and how to defend the supports,” she said.