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An Ex vivo Culture System to Study Thyroid Development
Published on: June 6, 2014
Thyroid-Stimulating Hormone (TSH) Concentration at Birth in Belgian Neonates and Cognitive Development at Preschool
Caroline Trumpff1,2,3, Jean De Schepper4, Johan Vanderfaeillie5
1Unit of Public Health and Surveillance, Scientific Institute of Public Health, Rue Juliette Wytsman 14, 1050 Brussels, Belgium. caroline.trumpff@wiv-isp.be.
Insights
Mild iodine deficiency (MID) in late pregnancy, indicated by neonatal thyroid-stimulating hormone (TSH), did not impact preschooler cognitive development. Current iodine levels in Belgium appear sufficient to protect neurodevelopment in young children.
Area of Science:
- Endocrinology
- Neurodevelopmental Pediatrics
- Public Health Nutrition
Background:
- Mild iodine deficiency (MID) during pregnancy is a concern for fetal neurodevelopment.
- Thyroid-stimulating hormone (TSH) levels at neonatal screening can serve as a surrogate marker for maternal iodine status.
- Cognitive development in preschool children is a critical indicator of early-life influences.
Purpose of the Study:
- To investigate the association between mild iodine deficiency (MID) in late pregnancy and cognitive development in preschool children.
- To assess the utility of neonatal thyroid-stimulating hormone (TSH) levels as a marker for MID's impact on neurodevelopment.
- To determine if current iodine sufficiency in Belgium impacts cognitive outcomes in young children.
Main Methods:
- Retrospective cohort study of 311 Belgian preschool children (4-6 years old).
- Neonatal TSH levels (0.45-15 mIU/L) were used as a surrogate for maternal iodine status.
- Cognitive abilities assessed using the Wechsler Preschool and Primary Scale of Intelligence-third edition (WPPSI-III).
- Confounding factors including socioeconomic status, parental, and child characteristics were analyzed.
Main Results:
- Neonatal TSH concentration was not significantly associated with Full Scale or Performance IQ scores.
- Univariate analysis showed lower Verbal IQ in children with neonatal TSH 10-15 mIU/L, but this was not significant after adjusting for confounders.
- Findings suggest that current iodine deficiency levels in pregnant Belgian women are not severe enough to impact neurodevelopment.
Conclusions:
- Mild iodine deficiency during pregnancy, as indicated by neonatal TSH, does not appear to affect the cognitive development of Belgian preschool children.
- The study supports the hypothesis that current iodine intake among pregnant women in Belgium is adequate to prevent neurodevelopmental deficits.
- Further research may be needed to confirm these findings in populations with varying iodine intake levels.
Abstract:
The main objective of the study was to investigate the effect of MID during late pregnancy, assessed by the thyroid-stimulating hormone (TSH) concentration at neonatal screening, on cognitive development of preschool children. A retrospective cohort study including 311 Belgian preschool children of 4-6 years old was conducted. Children were selected at random from the total list of neonates screened in 2008, 2009, and 2010 by the Brussels new-born screening center. Infants with congenital hypothyroidism, low birth weight, and/or prematurity were excluded from the selection. The selected children were stratified by gender and TSH-range (0.45-15 mIU/L). Cognitive abilities were assessed using Wechsler Preschool and Primary Scale of Intelligence-third edition. In addition, several socioeconomic, parental, and child confounding factors were assessed. Neonatal TSH concentration-a surrogate marker for MID-was not associated with Full Scale and Performance IQ scores in children. Lower Verbal IQ scores were found in children with neonatal TSH values comprised between 10-15 mIU/L compared to lower TSH levels in univariate analysis but these results did not hold when adjusting for confounding factors. Current levels of iodine deficiency among pregnant Belgian women may not be severe enough to affect the neurodevelopment of preschool children.
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