Relationship of urinary iodine level between 8-10 year-old children and adults in coastal and mountain areas in Fujian Province / 中华地方病学杂志

ABSTRACT

Objective To explore the relationship of urinary iodine level between 8-10 year-old children and adults under the same living conditions in coastal and mountain areas in Fujian Province.Methods Representative coastal and mountainous rural areas (Xindian Town Xiang'an District Xiamen City and Yongfu Town Zhangping District Longyan City) were selected as survey sites.Morning fasting urine samples from local 8-10 year-old children and their parents and a random urine sample in the morning from these children were collected.Urinary iodine was determined using the arsenic cerium catalytic spectrophotometric method (WS/T 107-2006).Results The median urinary iodine of fasting urine samples which were collected from 147 8-10 year-old children in coastal rural areas (71 boys and 76 girls) was 163.5 μg/L (boys 161.0 μg/L,girls 170.9 μg/L),and the median urinary iodine of random urine samples was 190.8 μg/L (boys 208.7 μg/L,girls 177.0 μg/L),and the difference was not statistically significant between boys and girls (Z =-0.376,-0.678,all P ＞ 0.05).The median urinary iodine of fasting urine samples which were collected from 116 8-10 year-old children in mountain rural areas (66 boys and 50 girls) was 171.8 μg/L (boys 169.5 μg/L,girls 173.8 μg/L),and the median urinary iodine of random urine samples was 210.8 μg/L (boys 233.2 μg/L,girls 203.4 μg/L),and the difference was not statistically significant between boys and girls (Z =-0.413,-0.881,all P ＞ 0.05).The median urinary iodine of random urine samples which were collected from 8-10 year-old children in mountain rural areas was significantly higher than that of the morning fasting urine samples (Z =-2.789,P ＜ 0.05).The median urinary iodine of children's fathers in coastal rural areas was 177.0 μg/L,and the median urinary iodine of their mothers was 181.7 μg/L.There was no significant difference between coastal rural children and their parents (Z =-0.387,-0.658,all P ＞ 0.05),and there was also no significant difference between fathers and mothers (Z =-0.014,P ＞ 0.05).The median urinary iodine of children's fathers in mountain rural areas was 227.3 μg/L,and the median urinary iodine of their mothers was 237.4 μg/L There was a significant difference between mountain rural children and their parents (Z =-4.176,-4.373,all P ＜ 0.05),and there was no significant difference between fathers and mothers (Z =-0.291,P ＞ 0.05).Conclusions Urinary iodine level of school-age children does not reflect the actual urinary iodine level of adults.There is a difference between urinary iodine level of random urine sample and morning fasting urine sample.Attention should be paid to this difference when monitoring iodine nutrition in population.