Investigation and analysis of individual iodine nutrition among students aged 8 to 15 in Dongtai City, Jiangsu Province in 2021 / 中华地方病学杂志

ABSTRACT

Objective:To analyze the individual iodine nutrition status and its influencing factors among students aged 8 to 15 in Dongtai City, Jiangsu Province.Methods:From May to August 2021, a total of 905 students aged 8 to 15 were selected as survey subjects in Dongtai City based on the sampling method in the "National Monitoring Plan for Iodine Deficiency Disorders" (2016 version). Salt samples from students' homes were collected for salt iodine testing. Urine samples of students were collected for urinary iodine and creatinine testing. The creatinine correction method was used to estimate individual 24 h urinary iodine excretion and calculate iodine intake. At the same time, basic information (age, gender, height, weight, etc.) and consumption frequency of iodine rich foods (seafood, eggs, meat, milk, solid snacks) of students were collected through questionnaires and actual measurements.Results:The coverage rate of iodized salt in Dongtai City was 98.2% (889/905), the qualified rate of iodized salt was 97.9% (870/889), and the consumption rate of qualified iodized salt was 96.1% (870/905). The median estimated 24 h urinary iodine excretion was 179.7 μg/d. The median estimated iodine intake was 195.4 μg/d, the constituent ratio of estimated iodine intake < recommended nutrient intake (RNI) was 16.2% (147/905), RNI-tolerable upper intake level (UL) was 63.4% (574/905), and > UL was 20.3% (184/905). The medians estimated 24 h urinary iodine excretion of students aged 8-10, 11-13 and 14-15 were 157.4, 193.0 and 236.5 μg/d, respectively, and the difference was statistically significant ( H = 55.42, P < 0.001). The median estimated 24 h urinary iodine excretion of boys was higher than that of girls (222.6 vs 148.6 μg/d), and the median estimated 24 h urinary iodine excretion of urban students was higher than that of township students (215.6 vs 162.7 μg/d), the differences were statistically significant ( Z = - 8.41, - 5.66, P < 0.001). There were statistically significant differences in the median estimated 24 h urinary iodine excretion between students with different body mass index (weight loss, overweight, obesity, normal; H = 56.15, P < 0.001) and iodine rich foods consumption frequencies (seafood, meat, milk, eggs, solid snacks; H = 23.15, 21.20, 60.77, 20.01, 24.47, P < 0.001). Conclusion:Iodine deficiency or excess exists in students aged 8-15 in Dongtai City, and girls aged 8-10 who are physically emaciated are the focus of attention for iodine deficiency.