The influence of environmental and genetic factors on neurodevelopmental and comorbid somatic conditions
The influence of environmental and genetic factors on neurodevelopmental and comorbid somatic conditions
Autism Spectrum Disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD) are common neurodevelopmental conditions that often co-occur with somatic health problems. Yet, in adults, particularly for ASD, their associations and underlying mechanisms remain poorly understood. This thesis of Yiran Li provides new insights into these health risks across the lifespan, using some of the largest population datasets in the Netherlands.
In adolescents, we showed that exposure to fine particulate matter (air pollution) is linked to more severe ASD and ADHD symptoms. This is one of the first long-term studies to demonstrate the harmful impact of air pollution on adolescent neurodevelopment, with implications for public health and environmental policy.
In adults, we found that people with more severe ASD symptoms are more likely to have conditions such as food allergy, irritable bowel syndrome, pain, and fatigue. Part of this overlap is due to shared genetics. These results highlight the need for healthcare professionals to recognize and address these health problems in adults with ASD, an area long overlooked.
Finally, using the Dutch nationwide data from more than 8 million individuals, we found that people with ASD faced increased and earlier risks of cardiometabolic conditions. Extending analyses to 15 million people across three generations, we showed that neurodevelopmental and cardiometabolic conditions cluster within families, reflecting both genetic and environmental influences.
The studies from this thesis have been published in leading international journals, such as Nature Mental Health and Translational Psychiatry. Together, these findings call for prevention, early detection, and integrated healthcare for ASD and ADHD across the lifespan.