Department of Obstetrics and Gynaecology, Faculty of Health Sciences, Walter Sisulu University, Mthatha, South Africa
Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.
BMJ Open. 2021 Feb 10;11(2):e043505. doi: 10.1136/bmjopen-2020-043505.
Although subclinical hypothyroidism in pregnancy is one of the established risk factors for pre-eclampsia, the link between iodine deficiency, the main cause of hypothyroidism, and pre-eclampsia remains uncertain. We conducted a systematic review to determine the iodine nutrition status of pregnant women with and without pre-eclampsia and the risk of pre-eclampsia due to iodine deficiency.
MEDLINE, EMBASE, Google Scholar, Scopus and Africa-Wide Information were searched up to 30th June 2020. Random-effect model meta-analysis was used to pool mean difference in urinary iodine concentration (UIC) between pre-eclamptic and normotensive controls and pool ORs and incidence rates of pre-eclampsia among women with UIC <150 µg/L.
Five eligible studies were included in the meta-analysis. There was a significant difference in the pooled mean UIC of 254 pre-eclamptic women and 210 normotensive controls enrolled in three eligible case-control studies (mean UIC 164.4 µg/L (95% CI 45.1 to 283.6, p<0.01, I >50)). The overall proportions of pre-eclampsia among women with UIC <150 µg/L and UIC >150 µg/L in two cross-sectional studies were 203/214 and 67/247, respectively, with a pooled OR of 0.01 (95% CI 0 to 4.23, p=0.14, I >50) for pre-eclampsia among women with UIC >150 µg/L. The overall incidence of pre-eclampsia among women with UIC <150 µg/L and UIC >150 µg/L in two cohort studies was 6/1411 and 3/2478, respectively, with a pooled risk ratio of 2.85 (95% CI 0.42 to 20.05, p=0.09, I <25).
Although pre-eclamptic women seem to have lower UIC than normotensive pregnant women, the available data are insufficient to provide a conclusive answer on association of iodine deficiency with pre-eclampsia risk.
CRD42018099427.
尽管妊娠亚临床甲状腺功能减退症是子痫前期的既定危险因素之一，但碘缺乏症（导致甲状腺功能减退症的主要原因）与子痫前期之间的联系仍不确定。我们进行了一项系统评价，以确定患有和不患有子痫前期的孕妇的碘营养状况以及由于碘缺乏而导致子痫前期的风险。
截至 2020 年 6 月 30 日，检索了 MEDLINE、EMBASE、Google Scholar、Scopus 和 Africa-Wide Information。使用随机效应模型荟萃分析来汇总子痫前期患者与血压正常对照者之间尿碘浓度（UIC）的平均差异，并汇总 UIC<150μg/L 的妇女中子痫前期的 OR 和发病率。
五项符合条件的研究被纳入荟萃分析。在纳入的三项符合条件的病例对照研究中，254 名子痫前期患者和 210 名血压正常对照者的平均 UIC 存在显著差异（平均 UIC 为 164.4μg/L（95%CI 45.1 至 283.6，p<0.01，I >50））。两项横断面研究中，UIC<150μg/L 和 UIC>150μg/L 的妇女中子痫前期的总体比例分别为 203/214 和 67/247，UIC>150μg/L 的妇女中子痫前期的汇总 OR 为 0.01（95%CI 0 至 4.23，p=0.14，I >50）。两项队列研究中，UIC<150μg/L 和 UIC>150μg/L 的妇女中子痫前期的总发病率分别为 6/1411 和 3/2478，UIC<150μg/L 的妇女中子痫前期的汇总风险比为 2.85（95%CI 0.42 至 20.05，p=0.09，I <25）。
尽管子痫前期患者的 UIC 似乎低于血压正常的孕妇，但现有数据不足以提供关于碘缺乏与子痫前期风险之间关联的明确答案。
PROSPERO 注册号：CRD42018099427。
