Iodine nutritional status of population before and after adjusting the salt iodine concentration in Yunnan Province / 中华地方病学杂志

ABSTRACT

Objective To analyze the iodine nutritional status in the key populations before and after the adjustment of iodized salt in Yunnan Province,and to provide scientific basis for adjusting the strategy of prevention and treatment timely.Methods The probability proportional to size sampling method was employed in the investigation.In the pre-adjustment period (2011) and the post-adjustment period (2014),the changes in the residents' iodized salt,the urinary iodine and goiter prevalence of children aged 8-10,the urinary iodine of pregnant women and lactating women were analyzed.Results Before and after adjusting the salt iodine concentration,the coverage rate of iodized salt was 99.1％ (1 196/1 207) and 99.2％ (1 532/1 545),respectively,the mean of salt iodine after the adjustment (23.6 mg/kg) was significantly lower than that of before (30.1 mg/kg,F =17.287,P ＜ 0.01).There was significant difference in the iodine nutritional status of children from 271.4 to 180.9 μg/L (Z=-12.883,P ＜ 0.01).The difference of iodine nutritional status in pregnant women between pre-adjustment (217.3 μg/L) and postadjustment (143.7 μg/L) was also significant (Z =9.997,P ＜ 0.01).The thyroid goiter rate of children had inceased from 1.7％ (21/1 207) to 2.1％ (33/1 549),the difference was not statistically significant between the groups (x2=0.539,P ＞ 0.05).Conclusions After adjusting the salt iodine concentration in Yunnan Province,iodine nutrition of children has decreased from more than adequate level to adequate level,thyroid goiter rate of children has remained at the low level,and iodine nutrition of pregnant women is sightly lower than adequate level,but iodine deficiency of pregnant women is at a low risk because of the good iodized salt coverage.The new standard of iodized salt is appropriate,and it is more favorable to health in Yunnan Province.