Relationship Between Urinary Iodine Concentration and the Prevalence
                    of Thyroid Nodules and Subclinical Hypothyroidism

Huachao Zhu; Pu Chen; Xi Ding; Yanru Zhao

doi:10.1055/a-2258-8258

Hormone and Metabolic Research, Table of Contents

Horm Metab Res 2024; 56(05): 368-372
DOI: 10.1055/a-2258-8258

Original Article: Endocrine Care

Relationship Between Urinary Iodine Concentration and the Prevalence of Thyroid Nodules and Subclinical Hypothyroidism

Authors

Huachao Zhu

¹Department of Hematology, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, China
Pu Chen

²Department of Endocrinology, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, China
Xi Ding

²Department of Endocrinology, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, China
Yanru Zhao

²Department of Endocrinology, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, China

Abstract

The aim of the study was to investigate the iodine intake in the resident population in Xi’an and analyze the relationship between iodine nutritional status and the prevalence of subclinical hypothyroidism and thyroid nodules (TNs). A total of 2507 people were enrolled in Xi’an. Venous serum thyroid stimulating hormone (TSH), thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb), urinary iodine concentration (UIC), and thyroid ultrasonography were collected. Patients with abnormal TSH were checked for free thyroxine (FT4) and triiodothyronine (FT3). Adults in Xi’an had median UICs of 220.80 μg/L and 178.56 μg/l, respectively. A sum of 16.78% of people had subclinical hypothyroidism. Both iodine excess and iodine deficit increased the frequency of subclinical hypothyroidism. The lowest was around 15.09% in females with urine iodine levels between 200 and 299 μg/l. With a rate of 10.69%, the lowest prevalence range for males was 100–199 μg/l. In Xi’an, 11.37% of people have TNs. In comparison to other UIC categories, TN occurrences were higher in females (18.5%) and males (12%) when UIC were below 100 μg/l. In conclusion, iodine intake was sufficient in the Xi’an area, while the adults’ UIC remains slightly higher than the criteria. Iodine excess or deficiency can lead to an increase in the prevalence of subclinical hypothyroidism. Patients with iodine deficiency are more likely to develop TNs.

Keywords

urinary iodine - thyroid nodule - subclinical hypothyroidism - iIodine intake - hormone

Full Text

References

References
1 Jin X, Jiang P, Liu L. et al. The application of serum iodine in assessing individual iodine status. Clin Endocrinol (Oxf) 2017; 87: 807-814
2 Vanderpump MPJ. The epidemiology of thyroid disease. Br Med Bull 2011; 99: 39-51
3 Yan YR, Liu Y, Huang H. et al. Iodine nutrition and thyroid diseases in Chengdu, China: an epidemiological study. QJM 2015; 108: 379-385
4 Bürgi H. Iodine excess. Best Pract Res Clin Endocrinol Metab 2010; 24: 107-115
5 Zimmermann MB, Boelaert K. Iodine deficiency and thyroid disorders. Lancet Diabetes Endocrinol 2015; 3: 286-295
6 Assessment of iodine deficiency disorders and monitoring their elimination: a guide for programme managers, 3rd ed https://www.who.int/publications/i/item/9789241595827
7 Universal Salt Iodization: Global progress and public health success stories to address IDD through USI, key programme components, lessons learned at country level, and the way forward to reach USI globally. [(accessed on 1 February 2017)]; Available online: http://www.unsystem.org/scn/Publications/SCNNews/scnnews35.pdf
8 World Health Organization. Micronutrient Deficiencies: Iodine deficiency disorders. [(accessed on 1 February 2017)]; Available online: http://www.who.int/nutrition/topics/idd/en/
9 World Health Organization (WHO). Guideline: Fortification of food-grade salt with iodine for the prevention and control of iodine deficiency disorders. World Health Organization; Geneva, Switzerland: 2014
10 UNICEF Fortifying our Future: A snapshot report on food fortification. [(accessed on 1 February 2017)];2015 Sep; Available online: http://www.gainhealth.org/wp-content/uploads/2015/05/Fortifying-our-Future-A-SnapShot-Report-on-Food-Fortification1.pdf
11 Iodine Global Network Legislation Database. [(accessed on 30 January 2017)]; Available online: http://www.ign.org/cm_data/Salt11X14.png
12 UNICEF State of the World’s Children 2015. [(accessed on 1 February 2017)]; Available online: http://data.unicef.org/corecode/uploads/document6/uploaded_pdfs/corecode/SOWC_2015_Summary_and_Tables_210.pdf
13 Iodine Global Network Global Scorecard 2016: Moving toward optimal iodine status. [(accessed on 1 February 2017)]; Available online: http://www.ign.org/newsletter/idd_nov16_global_scorecard_2016.pdf
14 Li Y, Teng D, Ba J. et al. Efficacy and safety of long-term universal salt iodization on thyroid disorders: epidemiological evidence from 31 provinces of mainland China. Thyroid 2020; 30: 568-579
15 Sun D, Codling K, Chang S. et al. Eliminating iodine deficiency in China: achievements, challenges and global implications. Nutrients 2017; 9: 361
16 Sun X, Shan Z, Teng W. Effects of increased iodine intake on thyroid disorders. Endocrinol Metab (Seoul) 2014; 29: 240-247
17 Laurberg P, Bülow Pedersen I, Knudsen N. et al. Environmental iodine intake affects the type of nonmalignant thyroid disease. Thyroid 2001; 11: 457-469
18 Mikulska AA, Filipowicz D, Główka FK. et al. HPLC Analysis of the Urinary Iodine Concentration in Pregnant Women. Molecules 2021; 26: 6797
19 Zou Y, Li H, Pang J. et al. An evaluation of urine and serum iodine status in the population of Tibet, China: no longer an iodine-deficient region. Nutrition 2021; 82: 111033
20 Bakken KS, Oma I, Groufh-Jacobsen S. et al. The reliability of iodine concentration in diaper-retrieved infant urine using urine collection pads, and in their mothers’ breastmilk. Biomolecules 2020; 10: 295
21 Mei L, Peirong Y, Weifeng C. Analysis of iodine nutritional status of pregnant women in Baoji city, Shaanxi Province during the three-year special action for endemic disease prevention and control from 2018 to 2020. 2022; 41: 135-138
22 Liu SCZ, Jia Q, Su X. et al. Diagnostic criterion of endemic goiter (WS 276–2007). Beijing, China: People’s Medical Publishing House; 2007
23 Pattanayak P, Singh SK, Gulati M. et al. Microfluidic chips: recent advances, critical strategies in design, applications and future perspectives. Microfluid Nanofluid 2021; 25: 99
24 Shi Xuehua CW, Li P, He S. et al. Investigation and analysis of adult thyroid health and iodine nutrition in different water iodine areas in Xi ’an. Chin J Endemiol 2020; 39: 892-896
25 Du Y, Gao Y, Meng F. et al. Iodine deficiency and excess coexist in china and induce thyroid dysfunction and disease: a cross-sectional study. PLoS One 2014; 9: e111937
26 Zhao W, Han C, Shi X. et al. Prevalence of goiter and thyroid nodules before and after implementation of the universal salt iodization program in mainland China from 1985 to 2014: a systematic review and meta-analysis. PLoS One 2014; 9: e109549
27 Ning Z, Hai-qin W. The relationship between iodine and subclinical hypothyroidism. Med Rev 2013; 19: 298-300
28 Chen Z, Xu W, Huang Y. et al. Associations of noniodized salt and thyroid nodule among the Chinese population: a large cross-sectional study. Am J Clin Nutr 2013; 98: 684-692
29 Kim HJ, Kim NK, Park HK. et al. Strong association of relatively low and extremely excessive iodine intakes with thyroid cancer in an iodine-replete area. Eur J Nutr 2017; 56: 965-971
30 Zimmermann MB, Jooste PL, Pandav CS. Iodine-deficiency disorders. Lancet 2008; 372: 1251-1262
31 Kopp P, Kimura ET, Aeschimann S. et al. Polyclonal and monoclonal thyroid nodules coexist within human multinodular goiters. J Clin Endocrinol Metab 1994; 79: 134-139
32 Biondi B, Cappola A, Cooper DS. Subclinical hypothyroidism: a review. JAMA 2019; 322: 153-160
33 Chen C, Xu H, Chen Y. et al. Iodized salt intake and its association with urinary iodine, thyroid peroxidase antibodies, and thyroglobulin antibodies among urban Chinese. Thyroid 2017; 27: 1566-1573
34 Rayman MP. Multiple nutritional factors and thyroid disease, with particular reference to autoimmune thyroid disease. Proc Nutr Soc 2019; 78: 34-44