Abstract
Background: Severe maternal iodine deficiency during pregnancy leads to marked intellectual disability in the offspring. Although recent studies showed that even mild-to-moderate maternal iodine deficiency is associated with lower intelligence quotient and attention deficit hyperactivity disorder in offspring, the underlying neurobiological mechanism of these associations remains unknown. The aim of this study was to investigate the association of maternal iodine excretion during pregnancy with offspring brain morphology during pre-adolescence. Methods: This study was embedded within Generation R, a prospective population-based birth cohort in Rotterdam, the Netherlands. We included 990 mother–child pairs with data on urinary iodine concentration (UIC) and creatinine during pregnancy. The UIC was assessed at <18 and/or 18–25 weeks of gestation and offspring brain imaging data were acquired with magnetic resonance imaging (MRI) at age 10 years. We used linear regression to study the association of the iodine-to-creatinine ratio (UI/Creat) with offspring brain MRI outcomes. Results: Maternal UI/Creat during pregnancy was not consistently associated with offspring brain morphology. A low UI/Creat (<150 lg/g) during pregnancy was nominally associated with smaller total gray matter volume, but this did not survive correction for multiple testing. Also, we could not identify a linear association between continuous iodine excretion and offspring brain morphology. Instead, our results suggest a curvilinear association between UI/Creat and brain morphology. In sensitivity analyses using the World Health Organization categorization for UIC values, both low and high UI/Creat were associated with smaller total gray matter volume. Conclusions: The current study provides some but no conclusive evidence for an association of maternal iodine excretion during pregnancy with offspring brain morphology. Our results suggest that the exact definition of the reference group is important because of potential non-linear associations, which could be leveraged in future studies.
| Original language | English |
|---|---|
| Pages (from-to) | 922-932 |
| Number of pages | 11 |
| Journal | Thyroid |
| Volume | 31 |
| Issue number | 6 |
| DOIs | |
| Publication status | Published - 8 Jun 2021 |
Bibliographical note
Funding Information:The general design of the Generation R Study was made possible by financial support from the Erasmus Medical Center, Rotterdam, the Erasmus University Rotterdam, ZonMw, the Netherlands Organization for Scientific Research, and the Ministry of Health, Welfare, and Sport. The current study was funded by the Netherlands Organisation for Health Research and Development (ZonMw) VICI (project 016.VICI.170.200, awarded to H.T.), VIDI Grant (project number 91717331, awarded to R.P.P.), and the Sophia Children’s Hospital Foundation (SSWO, grant S17– 19, awarded to H.T. and R.P.P). Funding bodies had no role in the design of the study, nor in the collection, analysis, and interpretation of data or writing the article.
Funding Information:
The general design of the Generation R Study was made possible by financial support from the Erasmus Medical Center, Rotterdam, the Erasmus University Rotterdam, ZonMw, the Netherlands Organization for Scientific Research, and the Ministry of Health, Welfare, and Sport. The current study was funded by the Netherlands Organisation for Health Research and Development (ZonMw) VICI (project 016.VICI.170.200, awarded to H.T.), VIDI Grant (project number 91717331, awarded to R.P.P.), and the Sophia Children?s Hospital Foundation (SSWO, grant S17?19, awarded to H.T. and R.P.P). Funding bodies had no role in the design of the study, nor in the collection, analysis, and interpretation of data or writing the article.
Publisher Copyright:
© Mary Ann Liebert, Inc.
