An Australian study has found a potential link between autoimmune disease and attention deficit hyperactivity disorder (ADHD).
The study took place over a decade, from 2000 to 2010, following more than 63,000 children born at full-term in New South Wales, Australia. Study author Timothy Nielsen, a PhD candidate at the University of Sydney, said that they were able to identify 12,610 mothers who had one or more of 35 common autoimmune diseases, such as type 1 diabetes, celiac disease, Crohn’s, psoriasis, multiple sclerosis, lupus, Sjogren’s or rheumatoid arthritis, to name a few. The children were identified as having a diagnosis of ADHD, or a prescription for stimulants.
The study also included a meta-analysis of existing research on this topic. The combined results of the longitudinal study and the meta-analysis found that when the mother had a diagnosis of any autoimmune disease, [this was] associated with a higher risk of ADHD in their child at later ages.
While researchers don’t know the exact reason why women with autoimmune disorders are more likely to have children with ADHD, researchers do have a hypothesis. It’s believed that maternal autoantibodies, which attack the mother’s own tissues, cross the placenta into the unborn fetus during pregnancy. Inflammatory molecules, therefore, could potentially do the same. These molecules could, in turn, alter fetal brain development, either by altering epigenetic markers, which turn certain genes on or off, or by impacting the function and formation of synapses, which allow nerve cells to communicate.
Nielsen explained, “These changes may lead directly to ADHD symptoms, or they may make the child more vulnerable to environmental risk factors.” He continued, “Our team is currently working on research into the causal mechanisms that underlie the association between autoimmune disease and ADHD, which may shed light on whether the severity of disease, symptoms, use of medications or other inflammatory factors modifies the risk of ADHD.”
This is the first study that explores the correlation between maternal autoimmune disease and the risk of ADHD in children. Other research has shown a link between autoimmune disease in mothers and other neurodevelopmental disorders, such as autism, obsessive-compulsive disorder (OCD), tics and Tourette’s syndrome.
Read the original study published in JAMA Pediatrics here: Association of Maternal Autoimmune Disease with ADHD in Children.