Neonatal thyroid-stimulating hormone and association with attention-deficit/hyperactivity disorder

Area of Science:

• Neurodevelopmental disorders
• Endocrinology
• Pediatric health

Background:

• Normal brain development relies on maternal, fetal, and neonatal thyroid function.
• Neonatal thyroid-stimulating hormone (TSH) screening identifies congenital hypothyroidism for early intervention.
• Disrupted thyroid homeostasis during development is linked to neurodevelopmental issues like ADHD.

Purpose of the Study:

• To investigate the association between low neonatal TSH levels and subsequent ADHD diagnosis.
• To analyze this relationship in a large, population-based birth cohort.

Main Methods:

• Utilized the Norwegian Mother, Father and Child Cohort Study (MoBa) with linkage to the Norwegian Patient Registry.
• Included 405 ADHD cases and 1,092 controls born between 2003-2008.
• Analyzed neonatal TSH concentrations below 10 mU/L measured in dried blood spots.

Main Results:

• A U-shaped relationship was observed between neonatal TSH levels and ADHD risk.
• Children in the lowest TSH quintile had a 1.6-fold higher odds of ADHD compared to the middle quintile.
• This association was significant in girls (OR 3.10) but not in boys, indicating a sex-specific effect.

Conclusions:

• Elevated ADHD risk is associated with low neonatal TSH levels (suggesting hyperthyroid status), primarily in girls.
• Future studies require sensitive assays for low TSH concentrations and larger cohorts for higher TSH levels.