不同时段尿样对尿碘监测结果的影响

The results of urinary iodine monitoring are affected by the urine collected in different period of time

目的探讨采集不同时段8~10岁学龄儿童尿样对群体尿碘中位数结果的影响。方法选择有代表性的沿海和山区地区,沿海分别于上午8：30、9：30、10：30、11：30点,下午14：30、15：30、16：30点采集学龄儿童7批次尿样;山区于上午8：30、10：30点,下午14：30、15：30点采集学龄儿童4批次尿样。采用砷铈催化分光光度方法和ATAGO UG-α数字式折射计测定尿碘含量和尿比重。结果沿海地区学龄儿童7批次尿碘中位数差异有统计学意义（χ2=62.129,P=0.000）,下午任一批次群体尿碘中位数均明显高于上午任一批次;山区学龄儿童4批次尿碘中位数差异无统计学意义（χ2=7.740,P=0.052）;学龄儿童尿碘含量与比重均呈正相关关系,各批次相关系数在0.5-0.8之间,P=0.000。结论上、下午学龄儿童尿碘水平有所差异,建议监测方案应明确尿样采集的时间;同时应关注尿比重对个体尿碘值的影响。

Objective To explore that the urine collected from 8-10-year-old children in different period of time had an influence on the median urinary iodine in population. Methods Chosen the typical coastal and mountainous areas. Collected 7 batches urine from the school-age children in coastal area at 8： 30,9： 30,10： 30,11： 30, 14： 30,15： 30 and 16： 30. Collected 4 batches urine from the school-age children in mountainous area at 8： 30,10： 30, 14： 30,and 15： 30. The urinary iodine level was determined by arsenic cerium catalytic spectrophotometry. The urinary specific gravity was determined by ATAGO UG-α digital refractometer. Results Significant difference of the median urinary iodine of the 7 batches urine which were collected from the school-age children in coastal area was observed（ Z = 62. 129, P = 0. 000）. The median urinary iodine of the any batche urine which were collected in the afternoon was significantly higher than the median urinary iodine of the any batche urine which were collected in the morning. No significant difference of the median urinary iodine of the 4 batches urine which were collected from the school-age children in mountainous area was observed（ Z = 7. 740, P = 0. 052）. There was a positive correlation between the urinary iodine level of the school-age children and their urinary specific gravity, the correlation coefficients were 0. 5 ~ 0. 8,all P = 0. 000. Conclusion There is a difference of the urinary iodine level of the school-age children between the morning urine and the afternoon urine. So we suggest that the time we collect the urine should be clear in the monitoring scheme. At the same time, we should pay attention to the urine specific gravity which affect on the urine iodine value in individual.