Abstract
Background
Both insufficient and excessive iodine intake can lead to a broad range of disorders. A cross-sectional survey was conducted to assess iodine status in schoolchildren from Croatia.
Design
957 healthy 6 to 12-year-olds were enrolled (381 from northwestern region, 190 from eastern region, 215 from north Adriatic, and 171 from central Dalmatia region). Urinary iodine concentration (UIC) was measured in spot urine samples. Thyroid volume (Tvol) was recorded by ultrasound device. Standard anthropometric measures were taken, and body surface area (BSA) was determined. Tvol medians were calculated as a function of age, sex and BSA and compared with reference values.
Results
Total sample size included 490 boys and 467 girls. Overall median UIC was 250.68 µg/L, with statistically significant variance in geographical regions (median UIC was 244.71 µg/L in northwestern, 208.02 µg/L in eastern, 216.07 µg/L in north Adriatic and 366.43 µg/L in central Dalmatia region). There were 10.08% of samples with UIC < 100 mcg/L while 38.24% of samples had UIC > 300 mcg/L. Age-matched Tvol medians in schoolchildren from all regions of Croatia were at the upper limits of reference values, but in north Adriatic and central Dalmatia exceeded the 97th percentile. BSA-matched Tvol was within the reference range in all regions.
Conclusions
Our results demonstrate sufficient (more than adequate) iodine intake in schoolchildren of Croatia, and excessive iodine intake in central Dalmatia region. Total thyroid volumes in schoolchildren of Croatia were within the normal range, however borderline enlarged age-matched thyroid glands were observed in coastal areas.
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Data availability
Data described in the manuscript will be made available upon reasonable request from the corresponding author.
References
Laurberg P, Cerqueira C, Ovesen L, Rasmussen LB, Perrild H, Andersen S, et al. Iodine intake as a determinant of thyroid disorders in populations. Best Pract Res Clin Endocrinol Metab. 2010;24:13–27. https://doi.org/10.1016/j.beem.2009.08.013.
World Health Organization. United Nations Children’s Fund & International Council for the Control of Iodine Deficiency Disorders. Assessment of iodine deficiency disorders and monitoring their elimination. 3rd ed. Geneva, Switzerland: WHO, 2007.
Hatch-McChesney A, Lieberman HR. Iodine and iodine deficiency: a comprehensive review of a re-emerging issue. Nutrients. 2022;14:3474 https://doi.org/10.3390/nu14173474.
Zimmermann MB. The role of iodine in human growth and development. Semin Cell Dev Biol. 2011;22:645–52. https://doi.org/10.1016/j.semcdb.2011.07.009.
EFSA NDA Panel (EFSA Panel on Panel on Dietetic Products Nutrition and Allergies 2014. Scientific opinion on dietary reference values for iodine. EFSA J. 2014;12:3660. https://doi.org/10.2903/j.efsa.2014.3660.
Kusić Z, Jukić T, Rogan SA, Jureša V, Dabelić N, Staničić J, et al. Current status of iodine intake in Croatia-the results of 2009 survey. Coll Antropol. 2012;36:123–8.
Zimmermann MB. Iodine deficiency. Endocr Rev. 2009;30:376–408. https://doi.org/10.1210/er.2009-0011.
Ba DM, Ssentongo P, Na M, Kjerulff KH, Liu G, Du P, et al. Factors associated with urinary iodine concentration among women of reproductive age, 20-49 years old, in Tanzania: a population-based cross-sectional study. Curr Dev Nutr. 2020;4:nzaa079. https://doi.org/10.1093/cdn/nzaa079.
Henjum S, Abel MH, Meltzer HM, Dahl L, Alexander J, Torheim LE, et al. Er inntaket av jod i befolkningen tilstrekkelig? [Is iodine intake adequate in Norway?]. Tidsskr Nor Laegeforen. 2019;139:Norwegian. https://doi.org/10.4045/tidsskr.18.0319.
Gärtner R. Recent data on iodine intake in Germany and Europe. J Trace Elem Med Biol. 2016;37:85–89. https://doi.org/10.1016/j.jtemb.2016.06.012.
The Iodine Global Network. Global scorecard of iodine nutrition in 2021 in the general population based on school-age children (SAC). IGN: Ottawa, Canada. 2021. https://www.ign.org/cm_data/IGN_Global_Scorecard_2021_7_May_2021.pdf. Accessed 1 Aug 2022.
Ittermann T, Albrecht D, Arohonka P, Bilek R, de Castro JJ, Dahl L, et al. Standardized map of iodine status in Europe. Thyroid 2020;30:1346–54. https://doi.org/10.1089/thy.2019.0353. Epub 2020 Jul 15. Erratum in: Thyroid. 2022 May;32(5):603.
Jukić T, Zimmermann MB, Granić R, Prpić M, Krilić D, Jureša V, et al. Sufficient Iodine Intake in School children from the Zagreb Area: assessment with dried blood spot thyroglobulin as a new functional biomarker for iodine deficiency. Acta Clin Croat. 2015;54:424–31.
Farebrother J, Zimmermann MB, Andersson M. Excess iodine intake: sources, assessment, and effects on thyroid function. Ann NY Acad Sci 2019;1446:44–65. https://doi.org/10.1111/nyas.14041.
Xiu L, Zhong G, Ma X. Urinary iodine concentration (UIC) could be a promising biomarker for predicting goiter among school-age children: a systematic review and meta-analysis. PLoS One 2017;12:e0174095. https://doi.org/10.1371/journal.pone.0174095. Erratum in: PLoS One. 2017 Jul 7;12 (7):e0181286.
Zimmermann MB, Aeberli I, Andersson M, Assey V, Yorg JA, Jooste P, et al. Thyroglobulin is a sensitive measure of both deficient and excess iodine intakes in children and indicates no adverse effects on thyroid function in the UIC range of 100-299 μg/L: a UNICEF/ICCIDD study group report. J Clin Endocrinol Metab. 2013;98:1271–80. https://doi.org/10.1210/jc.2012-3952.
Brunn J, Block U, Ruf G, Bos I, Kunze WP, Scriba PC Volumetrie der Schilddrüsenlappen mittels Real-time-Sonographie [Volumetric analysis of thyroid lobes by real-time ultrasound (author’s transl)]. Dtsch Med Wochenschr. 1981;106:1338-40. German. https://doi.org/10.1055/s-2008-1070506.
Mosteller RD. Simplified calculation of body-surface area. N Engl J Med. 1987;317:1098. https://doi.org/10.1056/NEJM198710223171717.
Vidranski V, Franceschi M, Krilić D, Jukić T, Mihaljević I, Kusić Z. Analytical evaluation of the new Seal Autoanalyzer 3 High Resolution for urinary iodine determination. Biochem Med (Zagreb) 2019;29:020711. https://doi.org/10.11613/BM.2019.020711. Erratum in: Biochem Med (Zagreb). 2019 Oct 15;29(3):031201.
WHO. Urinary iodine concentrations for determining iodine status deficiency in populations. Vitamin and Mineral Nutrition Information System. Geneva: World Health Organization; 2013. http://www.who.int/nutrition/vmnis/indicators/urinaryiodine, Accessed 1 Aug 2022.
Zimmermann MB, Hess SY, Molinari L, De Benoist B, Delange F, Braverman LE, et al. New reference values for thyroid volume by ultrasound in iodine-sufficient schoolchildren: a World Health Organization/Nutrition for Health and Development Iodine Deficiency Study Group Report. Am J Clin Nutr. 2004;79:231–7. https://doi.org/10.1093/ajcn/79.2.231.
Dold S, Zimmermann MB, Jukić T, Kusić Z, Jia Q, Sang Z, et al. Universal salt iodization provides sufficient dietary iodine to achieve adequate iodine nutrition during the first 1000 days: a cross-sectional multicenter study. J Nutr. 2018;148:587–98. https://doi.org/10.1093/jn/nxy015.
Mannar MV. Making salt iodization truly universal by 2020. IDD Newsl. 2014;42:12–15.
Kusić Z, Novosel SA, Dabelić N, Punda M, Roncević S, Labar Z, et al. Croatia has reached iodine sufficiency. J Endocrinol Invest. 2003;26:738–42. https://doi.org/10.1007/BF03347356.
World Health Organization. Trace elements in human nutrition and health. Indicators for assessing iodine deficiency disorders and their control through salt iodization. Geneva (Switzerland); WHO; 1996.
Hlucny K, Alexander BM, Gerow K, Larson-Meyer DE. Reflection of dietary iodine in the 24 h urinary iodine concentration, serum iodine and thyroglobulin as biomarkers of iodine status: a pilot study. Nutrients 2021;13:2520. https://doi.org/10.3390/nu13082520.
World Health Organization. Global Action Plan for the Prevention and Control of Noncommunicable Diseases 2013–2020. Geneva, Switzerland: World Health Organization; 2013.
Jelaković B, Kaić-Rak A, Milicić D, Premuzić V, Skupnjak B, Reiner Z. Manje soli-vise zdravlja. Hrvatska inicijativaza smanjenje prekomjernog unosa kuhinjske soli (CRASH) [Less salt-more health.Croatian action on salt and health (CRASH)]. Lijec Vjesn.2009;131:87–92. Croatian.
Drenjančević-Perić I, Jelaković B, Lombard JH, Kunert MP, Kibel A, Gros M. High-salt diet and hypertension: focus on the renin-angiotensin system. Kidney Blood Press Res 2011;34:1–11. https://doi.org/10.1159/000320387.
WHO. Guideline: Sodium intake for adults and children. Geneva, World Health Organization (WHO), 2012.
Jelakovic B. Salt Intake in Croatia—EHUH 2 Report. [(accessed on October 24, 2022)]; In 41st Symposium Hypertension Highlights in 2020. Available online: https://kongresi.emed.hr/course/info.php?id=149.
World Health Organization. Multisectoral Action in Food Systems, Nutrition and Food Safety. Universal salt iodization and sodium intake reduction: compatible, cost-effective strategies of great public health benefit. 22 August 2022. https://www.who.int/publications/i/item/9789240053717 [(Accessed 19 May 2023)].
Acknowledgements
This study was conducted with support of Croatian Science Foundation project IP-2014-09-6499 grant. The research on goiter and iodine intake in Croatia was undertaken between 2014 and 2019.
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The authors’ contributions were as follows: ZK, TJ, AF—study design (project idea, development of the research plan, overall activities oversight). TJ, VV, IB, MR, MBB, IM, TBC—data acquisition and collection. DF, TJ, VV, IM, TBC—analyses of data and statistical analyses. DF, TJ—composition of the manuscript. All authors read and approved the final (submitted) version of the manuscript.
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Filipan, D., Vidranski, V., Bosak Butković, M. et al. Recent data on iodine intake in Croatian schoolchildren: results of 2014–2019 survey. Eur J Clin Nutr 77, 959–965 (2023). https://doi.org/10.1038/s41430-023-01301-y
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DOI: https://doi.org/10.1038/s41430-023-01301-y
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