Objective: To analyze the iodine nutrition status of children aged 8 to 10 years in Zhejiang Province from 2016 to 2021. Methods: A multi-stage stratified sampling method was used to select non-residential children aged 8 to 10 years from 90 counties in Zhejiang Province. A total of 114 103 children were included in the study from 2016 to 2021. Direct titration method and arsenic-cerium catalytic spectrophotometry were used to detect salt iodine content and urinary iodine level, respectively, to evaluate the iodine nutritional status of children. Ultrasound was used to detect thyroid volume and analyze the current prevalence of goiter in school-age children. Results: The age of 114 103 children was (9.04 ± 0.81) years old, with 50.0% of (57 083) boys. The median of iodine content M (Q1, Q3) in children's household salt was 23.00 (19.80, 25.20) mg/kg, including 17 242 non-iodized salt, 6 173 unqualified iodized salt, and 90 688 qualified iodized salt. The coverage rate of iodized salt was 84.89%, and the coverage rate of qualified iodized salt was 79.48%. The proportion of non-iodized salt increased from 11.85% in 2016 to 16.04% in 2021 (χ2trend=111.427, P<0.001). The median of urinary iodine concentration M (Q1, Q3) in children was 182.50 (121.00, 261.00) μg/L, among which the proportions of iodine deficiency, iodine suitability, iodine over suitability, and iodine excess were 17.25% (19 686 cases), 39.21% (44 745 cases), 26.85% (30 638 cases), and 16.68% (19 034 cases), respectively. The median of urinary iodine concentration in children in inland areas [M (Q1, Q3): 190.90 (128.80, 269.00) μg/L] was significantly higher than that in children in coastal areas [M (Q1, Q3): 173.00 (113.00, 250.30) μg/L] (P<0.001). From 2016 to 2021, a total of 39 134 ultrasound examinations were conducted, and 1 229 cases of thyroid enlargement were detected. The goiter rate was 3.14% (95%CI: 2.97%-3.32%). The incidence of goiter in children in coastal areas [3.45% (95%CI: 3.19%-3.72%), 641/18 604] was higher than that in children in inland areas [2.86% (95%CI: 2.64%-3.10%), 588/20 530] (P=0.001). Conclusion: From 2016 to 2021, the iodine nutrition level of children aged 8-10 years in Zhejiang Province is generally suitable, and the rate of goiter in children meets the limit of iodine deficiency disease elimination standards.
目的： 分析2016—2021年浙江省8~10岁儿童碘营养状况。 方法： 采用多阶段分层抽样方法抽取浙江省90个现场调查点8~10岁的非寄宿制儿童。采用直接滴定法和砷铈催化分光光度法分别检测盐碘含量和尿碘水平，以评价儿童的碘营养状况；采用超声法检测甲状腺容积，分析学龄儿童甲状腺肿的患病现况。 结果： 2016—2021年共纳入114 103名儿童，年龄为（9.04±0.81）岁，男生占50.0%（57 083名）；内陆地区占53.36%（60 881名）。儿童家庭食用盐中碘的含量M（Q1，Q3）为23.00（19.80，25.20）mg/kg，其中非碘盐17 242份、不合格碘盐6 173份、合格碘盐90 688份，碘盐覆盖率为84.89%，合格碘盐覆盖率为79.48%；非碘盐占比从2016年的11.85%增长至2021年的16.04%（χ2趋势=111.427，P<0.001）。儿童尿碘浓度M（Q1，Q3）为182.50（121.00，261.00）μg/L，其中碘不足、碘适宜、碘超适宜及碘过量的占比分别为17.25%（19 686例）、39.21%（44 745例）、26.85%（30 638例）和16.68%（19 034例）；内陆地区儿童尿碘浓度［M（Q1，Q3）：190.90（128.80，269.00）μg/L］高于沿海地区儿童［M（Q1，Q3）：173.00（113.00，250.30）μg/L］，差异有统计学意义（P<0.001）。2016—2021年共超声检查39 134名，检出甲状腺肿1 229例，甲状腺肿大率为3.14%（95%CI：2.97%~3.32%）；沿海地区儿童甲状腺肿大率［3.45%（95%CI：3.19%~3.72%），641/18 604］高于内陆地区儿童［2.86%（95%CI：2.64%~3.10%），588/20 530］，差异有统计学意义（P=0.001）。 结论： 2016—2021年浙江省8~10岁儿童碘营养水平总体适宜，儿童甲状腺肿大率符合碘缺乏病消除标准限值。.