Iodine nutritional status of population before and after system reform of salt industry in Gansu Province / 公共卫生与预防医学

ABSTRACT

Objective To understand the impact of system reform of salt industry on iodine nutrition of people in Gansu Province, and to provide a scientific basis for policy adjustment of relevant departments. Methods The investigation period (2014-2021) was divided into two sub-periods before system reform of salt industry (2014-2016) and after system reform of salt industry (2017-2021). Thirty counties were selected according to the method of “population proportional probability sampling (PPS)” in 2014. According to the iodine deficiency disease monitoring program of Gansu Province, from 2016 to 2021, children aged 8-10 years and pregnant women were taken as research objects to collect urine samples for urine iodine detection. Children in 2014 and 2018 were selected to measure thyroid volume. Results A total of 90 989 children urine iodine samples were investigated, and the median urinary iodine (MUI) of children was 194.70µg/L; 7 663 and 83,326 children's urinary iodine samples were investigated in the two periods, the MUI was 180.73 µg/L and 196.00 µg/L, respectively, and the difference was statistically significant (P<0.05). A total of 44 741 pregnant women's urinary iodine samples were investigated, and the MUI of pregnant women was 176.50 µg/L; 4 480 and 40 261 pregnant women's urinary iodine samples were investigated in the two periods, the MUI was 160.61 µg/L and 178.10 µg/L, respectively, and the difference was statistically significant (P<0.05). The thyroid volume of 1 555 children and 8 509 children was investigated in the two periods, the median thyroid volume was 2.70 mL and 2.55 mL , respectively, and the difference was statistically significant (P<0.05). The rates of goiter in children were 3.15% and 1.26%, respectively, and the difference was statistically significant (P<0.05). Conclusion The iodine nutrition of people in Gansu Province has not fluctuated significantly after the reform of salt industry system and has maintained an appropriate level. It is necessary to pay attention to the potential risk of insufficient iodine nutrition level and thyroid health of key populations such as children and pregnant women and strengthen health education of scientific iodine supplementation.