水源性高碘对儿童智力影响的Meta分析

Effect of Water-borne Excessive Iodine on Intelligence of Children: a Meta-analysis.

目的水源性高碘对儿童智力发育的影响已经引起国内外研究者的广泛关注,本研究旨在探讨水源性高碘对儿童智商(intelligence quotient,IQ)的影响。方法通过计算机检索和手工检索国内外发表的相关文献,进行质量评价后按一定标准筛选文献,得到有关水源性高碘与儿童智力之间关系符合标准的9篇文献,采用RevMan5.2软件进行Meta分析。结果 9篇文献共涉及13项研究,累计高碘组共1 392人,对照组共1 175人。分析结果发现高碘组比对照组儿童智商减少0.17分(95%CI-0.33,-0.01),差异有统计学意义(Z=2.10,P<0.05)。以水碘含量分亚组,当水碘<800μg/L时,高碘组与对照组儿童智商差异无统计学意义(Z=1.07,P>0.05);而当水碘>800μg/L时,高碘组比对照组儿童智商减少0.23分(95%CI-0.44,-0.02),差异有统计学意义(Z=2.17,P<0.05)。以智力调查方法分亚组,使用联合瑞文量表测验的研究,高碘使儿童智商下降0.98分(95%CI-2.80,0.85),但差异无统计学意义(Z=1.05,P>0.05);使用中国比内量表测验的研究,高碘使儿童智商下降6.67分(95%CI-9.62,-3.71),差异有统计学意义(Z=4.42,P<0.05);使用韦氏量表测验的研究,高碘使儿童智商下降7.23分(95%CI-10.32,-4.14),差异有统计学意义(Z=4.58,P<0.05)。结论目前研究证据尚不能认为高水碘会造成儿童智力下降。

Objectives To investigate the effect of water-borne excessive iodine on the intelligence of children in China. Methods Literatures on the relationship between water-borne excessive iodine and the IQ of children were searched by computer from the database and manual retrieval. A total of 9 relevant literatures that met the inclusion criteria were included for Meta-analysis. Meta-analysis was performed with RevMan 5. 2. Results In the 9 literatures involved with 13 researches,1 392 children were included as a excessive iodine group and 1 175 children as a control group,the IQ in the excessive iodine group decreased 0. 17 points（95% CI- 0. 33,- 0. 01） significantly lower than that in the control group（Z = 2. 10,P 〈 0. 05）. When literatures were distinguished by water iodine concentration（WI）,in the lower water iodine area（WI 〈800 μg/L）,no significant difference（Z =1.07,P 〉0.05） was observed on the IQ of children between the excessive water iodine group and the control group; and in the higher water iodine area（WI 〉 800 μg /L）,the IQ of children in the excessive iodine group decreased 0. 23（95% CI ^- 0. 44,-0. 02） points significantly lower than the control group（Z = 2. 17,P 〈 0. 05）. When the data were analyzed by different IQ test methods,the IQ of children tested by CRT in the excessive iodine group decreased 0. 9 points（95% CI-2. 80,0. 85） lower than the control group,but there was no significant difference between the two groups（Z = 1. 05,P 〉 0. 05）. When the IQ of children was tested by Chinese Binet Intelligence Scale,the excessive iodine group decreased 6. 67 points（95% CI- 9. 62,- 3. 71） and significantly lower than the control group（Z = 4. 42,P 〈 0. 05）.When the IQ of children was tested by Wechsler Intelligence Scale,the IQ of children decreased 7. 23 points（95%CI- 10. 32,- 4. 14） and significantly lower than the control group（Z = 4. 58,P 〈 0. 05）. Conclusions There was no sufficient evidence to prove that excessive water iodine could cause a decrease of IQ in children.