Influencing factors of thyroid volume in children aged 8 - 10 in Yunnan Province / 中华地方病学杂志

ABSTRACT

Objective:To analyze the influencing factors of thyroid volume in children aged 8 - 10 in Yunnan Province, and provide scientific basis for improving iodine deficiency disorders monitoring.Methods:From March to July 2020, in 129 counties (cities, districts) under the jurisdiction of Yunnan Province, each county (city, district) was divided into 5 sampling areas based on east, west, south, north, and middle. One township was selected from each area, and 40 non-boarding children aged 8 - 10 from one primary school were selected from each township (age balanced, half male and half female) as survey subjects. One random urine sample and household edible salt samples were collected for urine iodine and salt iodine testing, and physical examination and thyroid volume measurement were conducted for children. The influencing factors of thyroid volume were analyzed using Pearson correlation.Results:A total of 24 934 urine samples were collected from children, with a median urine iodine of 233.2 μg/L. A total of 24 933 household edible salt samples were collected from children, the median salt iodine was 24.17 mg/kg, and the qualified rate of iodized salt was 96.63% (24 003/24 839); A total of 24 937 children were examined of their thyroid gland, with a median thyroid volume of 2.62 ml and a goiter rate of 1.12% (280/24 937). Among them, there were 12 410 boys and 12 527 girls, with thyroid volumes of 2.61 and 2.64 ml, respectively. The thyroid volume of boys was positively correlated with age, height, weight, body mass index, body surface area, and salt iodine ( r = 0.15, 0.21, 0.26, 0.18, 0.25, 0.03, P < 0.001). The thyroid volume of girls was positively correlated with age, height, weight, body mass index, and body surface area ( r = 0.17, 0.26, 0.28, 0.17, 0.27, P < 0.001). Conclusion:Children aged 8 - 10 in Yunnan Province are at an iodine excess level; the age, weight, height, body mass index, and body surface area are influencing factors of thyroid volume.