Monitoring of iodine deficiency disorders in the Republic of Tyva

Background: The Republic of Tyva is a region with a proven severe natural iodine deficiency and a high prevalence of IDD (iodine deficiency disorders). However, in the region in certain periods of time, measures were taken to eliminate iodine deficiency in the diet of the population. The article presents the results of the October 2020. by specialists of the Endocrinology Research Centre, a control and epidemiological study aimed at assessing the current state of iodine supply in the population of the Republic of Tyva. The study was carried out on behalf of the Ministry of Health of Russia within the framework of the state task «Scientific assessment of the need to take additional regulatory legal and other measures to eliminate iodine deficiency in pilot regions with severe iodine deficiency».

Aim: Assessment of iodine supply of the population of the Republic of Tuva.

Materials and methods: The research was carried out in three settlements of the republic — years. Kyzyl, Shagonar, Saryg-Sep settlement. A total of 227 pre-pubertal schoolchildren (8–10 years old) were examined with anamnesis collection, examination by an endocrinologist, palpation of the thyroid gland, collection of single urine samples into disposable eppendorfs, followed by freezing to minus 20–25 degrees to further determine the concentration of iodine in urine with using the cerium-arsenitic method in the laboratory (clinical diagnostic laboratory of the Federal State Budgetary Institution «National Medical Research Center of Endocrinology» of the Ministry of Health of Russia). In addition, all schoolchildren underwent an ultrasound examination of the thyroid gland (using a portable ultrasound machine LOGIQe (China) with a multifrequency linear transducer 10–15 MHz, in the supine position). The height and weight of children was determined according to the standard method at the time of the examination. A collection of samples of edible salt, which is used in families of schoolchildren, was carried out and the presence of iodine in it was determined by an express method for the qualitative determination of potassium iodate.

Parents of schoolchildren signed informed consent for the examination of children. Permission of the local ethical committee of the Endocrinology Research Centre — received, date: March 25, 2020, N 5.

Results: 227 schoolchildren of 8–10 years old were examined. The median concentration of iodine in urine was determined, the presence of iodine in food salt was investigated, and an ultrasound examination of the thyroid gland was carried out in order to clarify the iodine supply, the coverage of the use of iodized salt in nutrition and the prevalence of goiter.

The median concentration of iodine in urine was 153 μg/l, the frequency of goiter was 7.7%, and the proportion of households using iodized salt was 95.2%.

Conclusion: Results of assessment (median urinary iodine concentration) confirm that population of Tuva, Russian Federation, has optimum iodine nutrition. The prevalence of goiter in schoolchildren significantly decreased compared to earlier assessments. The proportion of households using iodized salt indicates the effectiveness of preventive measures in the ­region.

1. Dedov II, Gerasimov GA, Sviridenko NYu. Iododefitsitnye zabolevaniya v Rossiiskoi Federatsii (epidemiologiya, diagnostika, profilaktika). Metodicheskoe posobie. Moscow; 1999. (In Russ.).

2. Troshina EA, Platonova NM, Abdulkhabirova FM, Gerasimov GA. Iododefitsitnye zabolevaniya v Rossiiskoi Federatsii: vremya prinyatiya reshenii. Ed. by Dedov II, Mel’nichenko GA. Moscow: OAO «Konti-Print»; 2012. 232 p. (In Russ.).

3. Troshina EA. Zob. Moscow: OOO «Izdatel’stvo «Meditsinskoe informatsionnoe agenstvo»; 2012. 336 p. (In Russ.).

4. Melnichenko GA, Troshina EA, Platonova NM, et al. The awareness of Russians about iodine deficiency diseases and methods of it’s prevention. Clin Exp Thyroidol. 2017;12(3):25-30. (In Russ.). doi: https://doi.org/10.14341/ket2016325-30

5. Draft Federal Law «O profilaktike zabolevanii, svyazannykh s defitsitom ioda» (In Russ.).

6. Gerasimov GA. Russia – the land of contrasts. Clin Exp Thyroidol. 2017;13(2):6-12. (In Russ.). doi: https://doi.org/10.14341/ket201726-12

7. Герасимов Г.А., Фадеев В.В., Свириденко Н.Ю., Мельниченко Г.А., Дедов И.И. Йододефицитные заболевания в России. Простое решение сложной проблемы. - М.: Адамантъ, 2002

8. WHO, UNICEF, ICCIDD. Indicators for assessing Iodine Deficiency Disorders and their control through salt iodization. Geneva: WHO, WHO/Euro/NUT/ 1994.

9. WHO, UNICEF, ICCIDD. Progress towards the elimination if Iodine Deficiency Disorders (IDD) WHO/Euro/NUT/ 1999.

10. DeLong GR. Xinjiang and Tyva: Two agricultural approaches to iodine supplementation and the flux of iodine through the environment. NC, USA: Duke University Medical School, Durham; 1999.

11. Osokina IV. Epidemiologicheskie i immunogeneticheskie osobennosti iododefitsitnykh zabolevanii i sakharnogo diabeta u korennogo i prishlogo naseleniya srednei Sibiri. [dissertation]. Moscow; 2002. (In Russ.).

12. Normativnyi dokument. Rasporyazhenie Pravitel’stva Respubliki Tyva ot 12.05.2016 № 160-r. (In Russ.).

13. https://rosstat.gov.ru/

14. Zimmermann MB, Hess SY, Molinari L, 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(2):231-237. doi: https://doi.org/10.1093/ajcn/79.2.231

15. Dedov II, Arbuzova MI, Il’in AV. Iodnaya laboratoriya. Printsipy organizatsii raboty. Moscow; 2005. 48 p. (In Russ.).

16. Mokhort TV, Kolomiets ND, Petrenko SV, et al. Dynamic monitoring of iodine sufficiency in Belarus: results and problems. Probl Endocrinol. 2018;64(3):170-179. (In Russ.). doi: https://doi.org/10.14341/probl8686

17. Kachan VI, Mokhort TV, Kolomiets ND, et al. Strategy for elimination of iodine deficiency in belarus: evaluation of 10 years experience. Klinicheskaya i eksperimental’naya tireoidologiya. 2010;6(3):30. (In Russ.).

18. Gerasimov GA, Akopyan TE, Basalisyan MS, et al. Total elimination of iodine deficiency in Armenia by universal salt iodination. Klinicheskaya i eksperimental’naya tireoidologiya. 2006;2(3):51. (In Russ.).