Analysis of surveillance results of iodine deficiency disorders in Chongqing, 2017 / 中华地方病学杂志

ABSTRACT

Objective To master the current status of iodine deficiency disorders in Chongqing,and provide evidence for scientific prevention and treatment of iodine deficiency disorders.Methods In 2017,a cross-sectional survey method was adopted.In 26 districts (counties) in Chongqing,each district (county) was divided into five sampling areas by east,west,south,north and middle.One township/street (including at least one street) was selected in each area and one primary school was selected in each township/street.Forty non-boarding students aged 8 to 10 years old (half males and half females) were selected from each primary school.Their salt and instant urine samples were collected for salt iodine and urine iodine detection.At the same time,thyroid volume was measured in 8 to 10 years old students in 14 districts (counties).Results A total of 5 546 edible salt samples were collected,including 5 520 iodized salts,5 094 qualified iodized salts and 26 non-iodized salts.The average salt iodine content was 26.1 mg/kg and the range was 23.2 to 30.7 mg/kg.Iodized salt coverage rate,iodized salt pass rate,qualified iodized salt consumption rate,and non-iodized salt rate were 99.53％ (5 520/5 546),92.28％ (5 094/5 520),91.85％ (5 094/5 546),and 0.47％ (26/5 546),respectively.A total of 5 565 urine samples were tested,the median urinary iodine was 221.9 μg/L,urinary iodine ＜ 50 μg/L accounted for 2.98％ (166/5 565),50-99 μg/L accounted for 8.09％ (450/5 565),100-199 μg/L accounted for 31.66％ (1 762/5 565),200-299 μg/L accounted for 30.03％ (1 671/5 565),and ≥300 μg/L accounted for 27.24％ (1 516/5 565).A total of 3 111 children were tested for thyroid volume.The median thyroid volume was 2.6,2.9,3.1 ml in the 8th,9th,and 10th years,and the thyroid enlargement rate was 1.93％ (60/3 111).The districts (counties) had a goiter rate ranging from 0.45％ to 2.74％.Conclusions The consumption rates of qualified iodized salt and the median urinary iodine in Chongqing have reached the national standard for eliminating iodine deficiency disorders.The rate of goiter in children has remained at a low level,but the consumption rate of qualified iodized salt in some areas has shown a downward trend.The monitoring of the presence of non-iodized salt districts (counties) should be emphasized.