Department of Endocrinology and Nutrition, Hospital Universitario Central de Asturias (HUCA) [Central University Hospital of Asturias], Oviedo, Spain; Endocrinology, Nutrition, Diabetes and Obesity (ENDO) Research Group, Instituto de Investigación Sanitario del Principado de Asturias (ISPA) [Health Research Institute of the Principality of Asturias], Spain.
Department of Clinical Biochemistry, Hospital Universitario Central de Asturias (HUCA), Oviedo, Spain.
Endocrinol Diabetes Nutr (Engl Ed). 2023 Mar;70(3):162-170. doi: 10.1016/j.endien.2023.02.006.
Iodine deficiency is linked to thyroid dysfunction, particularly in pregnant women. The objective of this study was to ascertain the iodine levels of women in the second trimester of pregnancy, analysing the influence of iodine ingestion on urinary iodine concentration (UIC) and maternal thyroid function.
A prospective observational study of pregnant women from Health Area IV of Asturias (northern Spain) recruited before 13 weeks of gestation between May and June 2017. A questionnaire on iodine intake was completed at the first visit, and urine and serum samples were collected at baseline and again during the second trimester. UIC, thyroid stimulating hormone (TSH) and free thyroxine (FT4) obtained in the second trimester of gestation were analysed and related to iodine intake. Thyroid autoimmunity was also analysed in half of the pregnant women at baseline.
A total of 241 pregnant women were studied. Of these, 56.7% used iodised salt, 46.7% consumed ≥2 servings of dairy products daily and 88.1% took iodine supplements. Median UIC was 191μg/l (135.3-294μg/l), with 68.1% of the women having UIC ≥150μg/l. Only iodised salt consumption provided protection against iodine deficiency (odds ratio 0.35 [0.20-0.63], p=0.001). In women with no autoimmune thyroid disease (n=88), mean levels of TSH were lower in those that consumed iodised salt than in those that did not (respectively, 2.08±0.89mIU/l vs. 2.56±1.02mIU/l, p=0.025). In women with autoimmune thyroid disease (n=30), mean levels of TSH were higher in those that took iodine supplements than in those that did not (respectively, 2.97±1.25mIU/l vs. 1.16±0.41mIU/l, p=0.002).
The pregnant women studied from Health Area IV in Asturias maintain adequate nutritional iodine status in the second trimester of gestation. In our sample, only the consumption of iodised salt was associated with adequate iodine nutrition, without affecting maternal thyroid function. Most of the women used iodine supplements, which was linked to higher levels of TSH in pregnant women with autoimmune thyroid disease.
碘缺乏与甲状腺功能障碍有关，尤其是在孕妇中。本研究的目的是确定妊娠中期妇女的碘水平，分析碘摄入对尿碘浓度（UIC）和产妇甲状腺功能的影响。
2017 年 5 月至 6 月，在西班牙阿斯图里亚斯（北部）卫生区 IV 招募了妊娠 13 周前的孕妇，进行前瞻性观察性研究。在第一次就诊时完成了碘摄入量问卷，在基线和妊娠中期再次采集了尿液和血清样本。分析了妊娠中期获得的 UIC、促甲状腺激素（TSH）和游离甲状腺素（FT4），并将其与碘摄入量相关联。在基线时还对半数孕妇进行了甲状腺自身免疫分析。
共研究了 241 名孕妇。其中，56.7%的孕妇使用加碘盐，46.7%的孕妇每天食用≥2份乳制品，88.1%的孕妇服用碘补充剂。UIC 的中位数为 191μg/l（135.3-294μg/l），68.1%的孕妇 UIC≥150μg/l。只有食用加碘盐能预防碘缺乏（优势比 0.35 [0.20-0.63]，p=0.001）。在无自身免疫性甲状腺疾病的妇女（n=88）中，与未食用加碘盐的妇女相比，食用加碘盐的妇女 TSH 水平较低（分别为 2.08±0.89mIU/l 和 2.56±1.02mIU/l，p=0.025）。在自身免疫性甲状腺疾病的妇女（n=30）中，与未服用碘补充剂的妇女相比，服用碘补充剂的妇女 TSH 水平较高（分别为 2.97±1.25mIU/l 和 1.16±0.41mIU/l，p=0.002）。
研究中来自阿斯图里亚斯卫生区 IV 的孕妇在妊娠中期保持了足够的营养碘状态。在我们的样本中，只有食用加碘盐与充足的碘营养有关，而不会影响产妇甲状腺功能。大多数妇女使用了碘补充剂，这与患有自身免疫性甲状腺疾病的孕妇的 TSH 水平升高有关。
