Iodine status in vulnerable groups of Linxia Hui Autonomous Prefecture, China

To assess iodine status in vulnerable groups of Linxia Hui Autonomous Prefecture, China. We selected 5 villages in the east, south, west, north and center of 8 counties of Linxia Hui Autonomous Prefecture randomly. In each village, one primary school was identified and 80 students aged 8-10 years were randomly selected. At the same time, 20 pregnant women, 20 lactating women, 20 women of childbearing age and 20 young children (0-3 years) were randomly selected via existing township health center lists. The iodine content of household salt and drinking water and the urine in four population subsets (except school-aged children) was measured. The thyroids were examined in school-aged children. The iodine content in most household drinking water (90.2%) was less than 10µg/L. The percentage of households using adequately iodized salt was 83.2% and percentage of households using non-iodized salt was as high as 15%. The median urinary iodine concentration (UIC) of pregnant and lactating women, and women of child-bearing age was 89, 85 and 90µg/L, respectively, indicating an iodine deficiency. The median UIC of 0-3 year old babies was 107µg/L. The goiter rates of school-aged children were 10.6% by ultrasound and 9.9% by palpation. Low median UIC and high goiter rates were observed most frequently in counties with higher non-iodized salt and higher percentage of minority nationalities. Iodine deficiency has been a significant public health problem in Linxia Hui Autonomous Prefecture and still exists. Iodine supplement is needed to ensure adequate iodine nutrition for at-risk groups.