2017—2018年兰州市西固区儿童碘营养水平监测分析

Analysis of Iodine Nutritional Levels in Children in Xigu District of Lanzhou City between 2017 and 2018

目的了解2017~2018年兰州市西固区儿童的碘营养水平,为改善兰州市儿童的碘营养状况提供参考,为该地儿童的补碘策略提供一定的理论依据。方法采取分层抽样的方法,从兰州市西固区随机抽取400名(8~10)岁学龄儿童,采集其一次性尿样和家庭型食用盐样品并检测碘含量,对其碘营养状况、居民碘盐覆盖和合格情况进行分析。尿中碘化物采用国标《尿中碘的砷铈催化分光光度测定方法》进行测定,盐碘采用直接滴定法进行测定。结果①2017和2018年兰州市西固区儿童尿中碘化物中位数均在(200~300)μg/L之间,其碘摄入足量。经非参数Wilcoxon秩和检验,尿中碘化物中位数两年份间比较差异有统计学意义(Z=-3.23,P<0.01)。2017和2018年男童尿中碘化物(<100μg/L或>300μg/L),水平比较差异均无统计学意义(Z=-0.277,P>0.05或Z=-1.111,P>0.05)。2017和2018年女童尿中碘化物中位数<100μg/L者比较差异无统计学意义(Z=-0.441,P>0.05),但女童尿中碘化物中位数>300μg/L者比较差异具有统计学意义(Z=-2.293,P<0.05)。②2017和2018年兰州市西固区儿童盐碘中位数均在21~39 mg/kg之间,碘盐合格。儿童盐碘中位数两年份间比较差异无统计学意义(Z=-0.987,P>0.05)。经χ2检验,2017和2018年兰州市西固区儿童食用碘盐合格率两年份间比较差异有统计学意义(χ^2=278.276,P<0.01)。2017和2018年兰州市西固区儿童总碘盐覆盖率两年份间比较差异无统计学意义(χ^2=380.000,P>0.05)。③经Spearman秩相关分析,2017年儿童尿中碘化物与盐碘含量之间无相关性(r=0.055,P>0.05),而2018年儿童尿中碘化物与盐碘含量之间呈正相关性(r=0.287,P<0.01)。结论2017-2018年兰州市西固区儿童碘摄入超足量,且两年间女童尿中碘化物中位数>300μg/L者比较存在差异,儿童碘盐合格率低于国家标准。因此,应该普及碘盐的相关知识,提高合格碘盐使用率,预防碘缺乏病的发生,进而提高全人口的健康状况。

Objectives To understand the iodine nutritional level,provide reference for improving the iodine nutritional status,and to provide a theoretical basis for the iodine supplementation strategies of children in Xigu District of Lanzhou City from 2017 to 2018.Methods By stratified sampling,400 school-age children aged(8~10)years were randomly sampled from Xigu district of Lanzhou City.Their urine samples collected randomly at one time and family-type edible salt samples were collected and their iodine content was determined.Their iodine nutritional status,iodized salt coverage and its qualified rate were analyzed.Urine iodide was determined by arsenic-cerium catalytic spectrophotometry,and salt iodide content was determined by direct titration,respectively.Results Analysis of iodine nutrition levels of children in Xigu District of Lanzhou City from 2017 to 2018 showed:①The median urinary iodide levels of children in Xigu District of Lanzhou City in 2017 and 2018 were between 200 and 300μg/L,indicating their iodine intakes were sufficient.The non-parametric Wilcoxon rank sum test showed that a statistically significant difference in the median urinary iodine between these two years(Z=-3.23,P<0.01).There was no significant difference in urinary iodide(<100μg/L or>300μg/L)between boys in 2017 and 2018(Z=-0.277,P>0.05 or Z=-1.111,P>0.05).There was no significant difference in the median urinary iodine<100μg/L between girls in 2017 and 2018(Z=-0.441,P>0.05),but there was a statistical difference in the median urinary iodine of girls>300μg/L(Z=-2.293,P<0.05).②The median salt iodine content of children in Xigu District of Lanzhou City in 2017 and 2018 was between 21 and 39 mg/kg,and their iodized salts were qualified.There was no significant difference in the median salt iodine between these two years(Z=-0.987,P>0.05).According to theχ~2 test,the difference in the qualified rate of iodized salt for children in Xigu District of Lanzhou City in 2017 and 2018 was statistically significant(χ^2=278.276,P<0.01).There was no significant difference in the total iodized salt coverage of children in Xigu District of Lanzhou City between 2017 and 2018(χ^2=380.000,P>0.05).③According to Spearman rank correlation analysis,there was no correlation between urinary iodine and salt iodine content in children(r=0.055,P>0.05)in 2017,but there was a negative correlation between urinary iodine and iodized salt content in children in 2018(r=-0.287,P<0.01).Conclusions From 2017 to 2018,the iodine intake of children in Xigu District of Lanzhou City was excessive,and the urinary iodine median of girls>300μg/L was different between the two years.The qualified rate of children’s iodized salt was lower than the national standard.Therefore,the knowledge of iodized salt should be popularized,and the utilization rate of qualified iodized salt should be improved,in order to prevent the occurrence of iodine deficiency disorders,and to improve the health status of the whole population.