Maternal autoimmune diseases may be associated with increased attention-deficit/hyperactivity disorder (ADHD) in children, according to Australian researchers.
Their cohort study also found that specific maternal autoimmune conditions — including type 1 diabetes, psoriasis, and rheumatic fever or rheumatic carditis — were associated with an increased risk for their children to develop ADHD.
“These findings suggest possible shared genetic vulnerability between autoimmune disease and ADHD or a potential role for maternal immune activation in the expression of neurodevelopmental disorders in children,” Timothy Nielsen, MPH, of the University of Sydney in Sydney, Australia, and colleagues wrote in JAMA Pediatrics.
According to Nielsen and colleagues, autoimmune conditions affect up to 9% of the world’s population and disproportionately affect women of reproductive age. In addition, they pointed to a growing field of evidence suggesting that immune-related cells and proteins play a role in brain development and function, and that maternal immune activation via infection, autoimmune disease, and chronic inflammation during pregnancy increases the risk of neurodevelopmental disorders among children. However, few studies have actually addressed the association of maternal autoimmune disease with ADHD.
In this study, the authors’ objective was to evaluate the association of maternal autoimmune disease, as well specific autoimmune conditions, with ADHD in children.
The cohort study included children born in New South Wales, Australia, between 2000 and 2010 — these patients received follow-up through the end of 2014. The authors identified 12,610 children born to mothers with autoimmune disease who were propensity score matched with 50,440 unexposed children. Children were considered to have ADHD if they had received an authorization or filled prescription for stimulant treatment for ADHD or had a hospital diagnosis of the condition.
Nielsen and colleagues determined that a diagnosis of ADHD was more common among children born to mothers with autoimmune disease compared to unexposed children (6.98 vs 5.48 per 1000 person-years for boys and 2.32 vs 1.70 per 1000 person-years for girls). Thus, any maternal autoimmune disease (adjusted HR, 1.30; 95% CI, 1.15-1.46) was associated with an increase in the risk of ADHD diagnosis.
The same held true for a number of specific conditions, including:
- Type 1 diabetes (HR, 2.23; 95% CI, 1.66-3.00).
- Psoriasis (HR, 1.66; 95% CI, 1.02-2.70).
- Rheumatic fever or rheumatic carditis (HR, 1.75; 95% CI, 1.06-2.89).
In their systematic review and meta-analysis, the authors found that any autoimmune disease (HR, 1.20; 95% CI, 1.03-1.38), type 1 diabetes (HR, 1.53; 95% CI, 1.27-1.85), hyperthyroidism (HR, 1.15; 95% CI, 1.06-1.26), and psoriasis (HR, 1.31; 95% CI, 1.10-1.56) were all associated with ADHD.
The authors noted that maternal type 1 diabetes exhibited the largest hazard ratio in both the cohort study and meta-analysis and suggested that the association “may also be related to nonimmune aspects of T1D, such as glycemic control, as nonautoimmune diabetes has been associated with ADHD among children.” However, they also added that they could not draw specific conclusions regarding causation given the observational nature of the cohort study, as well as the studies in their systematic review and meta-analysis.
In an editorial accompanying the study, Søren Dalsgaard, MD, PhD, Aarhus University, Aarhus, Denmark, noted that while this study did not provide clear explanations concerning the mechanisms behind this association between autoimmune diseases and ADHD, “there is a growing body of evidence for associations between both the overall category and some specific autoimmune diseases and ADHD.”
Dalsgaard added that future studies on this question should involve different scientific disciplines, including epidemiology, animal modeling, genetics, and neuroimmunology.
“Our study provides justification for future studies that examine the effect of maternal autoimmune diseases, including biomarkers, condition severity, and management in pregnancy and in the periconception period, on neurodevelopmental disorders in children,” Nielsen and colleagues concluded. “It also highlights the importance of high quality multidisciplinary care for women with autoimmune diseases and their children.”
Nielsen and colleagues noted important limitations to their study, “most significantly the lack of outpatient or primary care records for identifying maternal autoimmune exposure, which is likely underascertained, particularly for disorders such as psoriasis that do not commonly result in hospitalization.” Other limitations included a lack of data on disease severity and medication usage among mothers during pregnancy, an inability to track children with ADHD who were not receiving medications during the study period, and an inability to fully assess symptom severity, domains, or comorbidities among ADHD cases that may have complicated the association.
Maternal autoimmune disease may be associated with attention-deficit/hyperactivity disorder (ADHD) in children.
Specific conditions — particularly type 1 diabetes — were associated with an increased risk of ADHD in this population-based cohort analysis.
Michael Bassett, Contributing Writer, BreakingMED™
The authors and editorialists had no relationships to disclose.
Cat ID: 136
Topic ID: 85,136,730,187,41,136,192,53,925