Menzies Research Institute Tasmania, University of Tasmania, Sandy Bay, Tasmania 7005, Australia.
J Clin Endocrinol Metab. 2013 May;98(5):1954-62. doi: 10.1210/jc.2012-4249. Epub 2013 Apr 30.
Severe iodine deficiency (ID) during gestation is associated with neurocognitive sequelae. The long-term impact of mild ID, however, has not been well characterized.
The purpose of this study was to determine whether children born to mothers with urinary iodine concentrations (UICs) <150 μg/L during pregnancy have poorer educational outcomes in primary school than peers whose mothers did not have gestational ID (UIC ≥150 μg/L).
This was a longitudinal follow-up (at 9 years old) of the Gestational Iodine Cohort. Pregnancy occurred during a period of mild ID in the population, with the children subsequently growing up in an iodine-replete environment.
Participants were children whose mothers attended The Royal Hobart Hospital (Tasmania) antenatal clinics between 1999 and 2001.
Australian national curriculum and Tasmanian state curriculum educational assessment data for children in year 3 were analyzed.
Children whose mothers had UIC <150 μg/L had reductions of 10.0% in spelling (-41.1 points, 95% confidence interval [CI], -68.0 to -14.3, P = .003), 7.6% in grammar (-30.9 points, 95% CI, -60.2 to -1.7, P = .038), and 5.7% in English-literacy (-0.33 points, 95% CI, -0.63 to -0.03, P = .034) performance compared with children whose mothers' UICs were ≥150 μg/L. These associations remained significant after adjustment for a range of biological factors (maternal age at birth of child, gestational length at time of birth, gestational age at time of urinary iodine collection, birth weight, and sex). Differences in spelling remained significant after further adjustment for socioeconomic factors (maternal occupation and education).
This study provides preliminary evidence that even mild iodine deficiency during pregnancy can have long-term adverse impacts on fetal neurocognition that are not ameliorated by iodine sufficiency during childhood.
妊娠期间严重碘缺乏（ID）与神经认知后遗症有关。然而，轻度 ID 的长期影响尚未得到很好的描述。
本研究旨在确定母亲在怀孕期间的尿碘浓度（UIC）<150μg/L 的儿童在小学的教育成果是否不如其母亲没有妊娠期 ID（UIC≥150μg/L）的同龄人。
这是妊娠期碘队列的纵向随访（9 岁时）。妊娠发生在人群轻度碘缺乏期间，随后儿童在碘充足的环境中成长。
参与者是母亲于 1999 年至 2001 年期间在塔斯马尼亚皇家霍巴特医院（Tasmania）产前诊所就诊的儿童。
分析了儿童在 3 年级的澳大利亚国家课程和塔斯马尼亚州课程教育评估数据。
母亲 UIC<150μg/L 的儿童在拼写方面下降了 10.0%（-41.1 分，95%置信区间[CI]，-68.0 至-14.3，P=0.003），语法方面下降了 7.6%（-30.9 分，95% CI，-60.2 至-1.7，P=0.038），英语语言方面下降了 5.7%（-0.33 分，95% CI，-0.63 至-0.03，P=0.034），与母亲 UIC≥150μg/L 的儿童相比。在调整了一系列生物学因素（孩子出生时母亲的年龄、出生时的妊娠长度、收集尿碘时的妊娠年龄、出生体重和性别）后，这些关联仍然显著。在进一步调整社会经济因素（母亲的职业和教育）后，拼写差异仍然显著。
本研究初步表明，即使是妊娠期间轻度碘缺乏也可能对胎儿神经认知产生长期的不利影响，而这种影响在儿童期碘充足时并不能得到改善。
