Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2017 Nov 22;12(11):e0187241.
doi: 10.1371/journal.pone.0187241. eCollection 2017.

Associations between thyroid dysfunction and developmental status in children with excessive iodine status

Inger Aakre  1   2 , Tor A Strand  2   3 , Khalil Moubarek  4 , Ingrid Barikmo  1 , Sigrun Henjum  1
Affiliations

Associations between thyroid dysfunction and developmental status in children with excessive iodine status

Inger Aakre et al. PLoS One. .

Abstract

Background and objective: Adequate iodine status and normal thyroid hormone synthesis are important for optimal child development. In this study, we explored whether young children's developmental status is associated with thyroid dysfunction in an area of chronic excessive iodine exposure.

Methods: We included 298 children between 18 and 48 months of age residing in Algerian refugee camps. Early child development was measured using the Ages and Stages Questionnaires, third edition (ASQ-3), consisting of five domains: Communication, Gross Motor, Fine Motor, Problem Solving and Personal-Social. Due to poor discriminatory ability in the Gross Motor domain, the total ASQ-3 scores were calculated both including and excluding this domain. Urinary iodine concentration (UIC), thyroid hormones (TSH, FT3 and FT4), thyroid antibodies and serum thyroglobulin (Tg) were measured.

Results: The median UIC was 451.6 μg/L, and approximately 72% of the children had a UIC above 300 μg/L. Furthermore, 14% had thyroid disturbances, of whom 10% had TSH outside the reference range. Children with thyroid disturbances and TSH outside the reference ranges had lower odds of being among the 66% highest total ASQ scores, with adjusted odds ratios (95% CI) of 0.46 (0.23, 0.93) and 0.42 (0.19, 0.94), respectively.

Conclusion: We found an association between thyroid dysfunction and poorer developmental status among children with excessive iodine intake. The high iodine intake may have caused the thyroid dysfunction and hence the delayed developmental status; however, other influential factors cannot be excluded. Optimal child development is important for a sustainable future. With iodine excess being an increasing problem globally, this subject should be further explored.

PubMed Disclaimer

Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist.

Figures

Fig 1
Fig 1. Flowchart for selection of Saharawi children from 2010 baseline study and 2013 follow-up study.
*low age, high age, deaf, and mute.
See this image and copyright information in PMC

References

    1. WHO. Assessment of Iodine Deficiency Disorders and Monitoring their Elimination. A guide for programme managers. World Health Organisation, International Council for Control of Iodine Deficiency Disorders, United Nations Children’s Fund; 2007.
    1. Zimmermann MB, Jooste PL, Pandav CS. Iodine-deficiency disorders. Lancet. 2008;372(9645):1251–62. doi: 10.1016/S0140-6736(08)61005-3 - DOI - PubMed
    1. Zimmermann BM. The role of iodine in human growth and development. Semin Cell Dev Biol. 2011;22:645–52. doi: 10.1016/j.semcdb.2011.07.009 - DOI - PubMed
    1. Prado EL, Dewey KG. Nutrition and brain development in early life. Nutr Rev. 2014;72(4):267–84. doi: 10.1111/nure.12102 - DOI - PubMed
    1. Zimmermann MB. Iodine deficiency. Endocr Rev. 2009;30(4):376–408. doi: 10.1210/er.2009-0011 - DOI - PubMed