Summary: Autism spectrum disorder (ASD) is a neurodevelopmental disorder with a varied clinical manifestation. There are common characteristics such as social and communication difficulties, restricted interests and repetitive behaviors. However emerging literature suggests that 50% of individuals with ASD also present with gastrointestinal symptoms. A study of 48,762 children also elucidated that children with ASD are approximately 47% more likely to be diagnosed with Crohn’s disease and 94% more likely to be diagnosed with ulcerative colitis. The authors of this paper aim to investigate associations between parental diagnosis of irritable bowel disease (IBD) and ASD in children, as well as genetic correlations between IBD and ASD. They found evidence of correlations between a parental diagnosis of IBD and autism in children, which are more positively associated with maternal parents. The paper also provides evidence of a potential genetic causal effect of IBD with ASD, particularly ulcerative colitis.
Evidence linking parental inflammatory bowel disease (IBD) with autism in children is inconclusive. We conducted four complementary studies to investigate associations between parental IBD and autism in children, and elucidated their underlying etiology. Conducting a nationwide population-based cohort study using Swedish registers, we found evidence of associations between parental diagnosis of IBD and autism in children. Polygenic risk score analyses of the Avon Longitudinal Study of Parents and Children suggested associations between maternal genetic liability to IBD and autistic traits in children. Two-sample Mendelian randomization analyses provided evidence of a potential causal effect of genetic liability to IBD, especially ulcerative colitis, on autism. Linkage disequilibrium score regression did not indicate a genetic correlation between IBD and autism. Triangulating evidence from these four complementary approaches, we found evidence of a potential causal link between parental, particularly maternal, IBD and autism in children. Perinatal immune dysregulation, micronutrient malabsorption and anemia may be implicated.
Article Publication Date: 02.06.22