Analysis on the survey results of iodine deficiency disorders of children aged 8-10 years and pregnant women in Shizuishan City of Ningxia Hui Autonomous Region during the year of 2017

Abstract

Objective To understand the status of iodine nutrition of children aged 8-10 years and pregnant women in Shizuishan City. Methods In 2017, five sampling districts were divided into east, west, south, north and middle districts in three counties (Dawukou District, Huinong District and Pingluo County) of Shizuishan City, one township (town, street) was selected in each district, one primary school was selected in each township (town, street), 40 children aged 8-10 years were selected in each primary school, and 20 pregnant women were selected in each township (town, street). In Dawukou District and Huinong District of Shizuishan City, 50 g of edible salt and 10 ml of urine samples were collected from the homes of children and pregnant women; in Pingluo County 50 g of edible salt samples were collected from the homes of children and pregnant women. Iodine in edible iodized salt was measured by redox titration and urinary iodine content was measured by arsenic-cerium catalytic spectrophotometer. Results A total of 900 edible salt samples were collected, the median iodine content in salt was 24.50 mg/kg, the coverage rate of iodized salt was 97.67% (879/900), the qualified rate of iodized salt was 86.92% (764/879), and the edible rate of qualified iodized salt was 84.89% (764/900). A total of 400 urine samples of children were tested, the median urinary iodine was 213 μg/L. There was statistically significant difference in urinary iodine among children between Dawukou District and Huinong District (the median urinary iodine was 246 and 194 μg/L, respectively, Z=-4.827, P 0.05). A total of 200 urine samples of pregnant women were tested, and the median urinary iodine was 173 μg/L. There were no significant differences in urinary iodine content between pregnant women in different counties(districts), and between pregnant women at different pregnancy stages (P > 0.05). Conclusion The iodine nutrition status of the children aged 8-10 years and pregnant women in Shizuishan City is generally at the appropriate level. Key words: Iodine; Deficiency diseases; Nutritional status; Salts; Urine