Analysis of surveillance results of iodine deficiency disorders in 2013 in Hainan Province

Abstract

Objective To analyze the coverage of iodized salt and the focus population iodine nutrition after implementing new standard of iodized salt in Hainan Province. Methods Eighteen cities (counties, districts) were divided into eastern coastal, western coastal and inland areas according to coastline and terrain of Hainan Province in 2013. One township (town, street) was sampled from each city (county, district) in the east, the west, the south, the north and the center of these areas. Four villages (committees) and 15 households in each village (committee), and 40 children aged 8-10 in one primary school, 20 pregnant women and lactating women were sampled from each township (town, street). Iodized salt samples collected from household were monitored by the method of direct titration; random urine samples of children aged 8-10, pregnant woman and lactating woman were tested by arsenic cerium catalytic spectrophotometry. Results Totally 6 310 edible salt samples were tested, and the median of salt iodine was 25.9 mg/kg. The coverage of iodized salt was 97.92% (6 179/6 310). Residents' consumption rate of qualified iodized salt reached 95.47% (6 024/6 310), and the rate of non-iodized salt was 2.08% (131/6 310). About 4 444 urine samples of children aged 8-10 were examined, and the median of urinary iodine was 165.4 μg/L, in which suitable urinary iodine (100-199 μg/L) accounted 49.3% (2 194/4 444); about 1 286 urine samples of lactating woman were examined, the median of urinary iodine was 122.3 μg/L, ≥100 μg/L was 60.6% (779/1 286); about 813 urine samples of pregnant woman were examined, the median of urinary iodine was 126.6 μg/L, 59.6% (485/813) of this group were urinary iodine deficiency (< 150 μg/L). There were significant differences between the three groups in the east, the middle and the west areas of Hainan Province (children: 176.7, 147.7, 158.0 μg/L, lactating women: 148.7, 108.7, 106.7 μg/L, pregnant women: 146.7, 108.0, 147.1 μg/L, H = 34.70, 26.76, 35.95, all P < 0.01). Conclusion The results have showed that pregnant woman are iodine deficiency, they should be given more iodine. Key words: Iodine; Urinary iodine; Surveillance