Gestational vitamin D deficiency and autism-related traits: the Generation R Study

Area of Science:

• Neuroscience
• Developmental Biology
• Public Health

Background:

• Autism spectrum disorders (ASD) and related traits are complex neurodevelopmental conditions.
• Identifying modifiable risk factors for ASD is a key research priority.
• Gestational vitamin D deficiency is implicated in altered brain development, suggesting a potential link to ASD and related traits.

Purpose of the Study:

• To investigate the association between maternal vitamin D deficiency during pregnancy and autism-related traits in offspring.
• To examine vitamin D status using maternal mid-gestation and neonatal cord blood samples.
• To assess autism-related traits using the Social Responsiveness Scale (SRS) in a large population-based cohort.

Main Methods:

• A population-based cohort study of 4229 mother-child pairs.
• Measurement of 25-hydroxyvitamin D (25OHD) levels in maternal serum (mid-gestation) and neonatal cord blood.
• Definition of vitamin D deficiency as 25OHD < 25 nmol/L and sufficiency as 25OHD > 50 nmol/L.
• Statistical analysis to determine the association between gestational vitamin D status and SRS scores at ~6 years of age, with adjustments for ancestry, genetic data, and season of blood sampling.

Main Results:

• Gestational vitamin D deficiency was significantly associated with higher (more abnormal) SRS scores in children at ~6 years.
• This association was observed using both mid-gestation maternal serum (β=0.06, P<0.001) and neonatal cord blood (β=0.03, P=0.01).
• The findings remained consistent across various sensitivity analyses, including restricted ancestry groups and continuous vitamin D measures.

Conclusions:

• Gestational vitamin D deficiency is associated with increased autism-related traits in a large population-based sample.
• Vitamin D supplementation during pregnancy may be a potential strategy to mitigate the risk of autism-related traits.
• Further research is warranted to confirm these findings and explore the efficacy of interventions.