Lower educational status interferes with maternal iodine intake during both pregnancy and lactation.

OBJECTIVE: To investigate factors affecting conscious iodine intake among pregnant and lactating women in a rural area in Hungary. METHODS: Pregnant women were studied and followed during lactation. Urinary and breast milk iodine concentration (UIC and MIC) were measured by inductively coupled plasma mass spectrometry. Potential interfering factors, including age, educational status and smoking were assessed. RESULTS: During pregnancy and lactation, mild iodine deficiency was observed; median UIC were 66 and 49 µg/L, respectively. Educational status was found to be a strong determinant of both iodine nutrition and smoking status during pregnancy (P < 0.01 and P < 0.001) and lactation (P < 0.001 and P < 0.01). While smoking and non-smoking lactating mothers had similar concentrations of urinary iodine (median UIC: 47 and 51 µg/L, P = 0.95), the breast milk of smoking mothers contained less iodine (median MIC: 150 and 203 µg/L, P = 0.03). CONCLUSIONS: Both low iodine intake and smoking contribute to the higher risk of iodine deficiency in women with lower educational status. In smokers, MIC is often low in spite of normal UIC, presumably due to the iodine transport blocking effect of the cigarette smoke towards breast milk; normal UIC may be misinterpreted as sufficient iodine supply towards the child. Antenatal health promotion strategies should focus on young women with lower educational status, even in regions where sufficient iodine intake has been achieved in non-pregnant adults.

Early Stage Graves' Disease is Uniformly Accompanied by Orbital Immune Activity even in Patients who Fail to Develop Orbithopathy during Follow-up.

PURPOSE: Graves' orbitopathy (GO) is a complication of Graves' disease (GD), the development of which cannot be predicted at the time of diagnosis of GD. Our aims were (i) to test if orbital 99mTc-labelled diethylenetriamine pentaacetic acid single-photon emission computer tomography (DTPA SPECT) can predict development of GO later during the course of the disease and (ii) to study whether orbital immune activity can be detected in GD patients who do not develop GO during follow-up. METHODS: Fifty-four orbits of 27 patients with newly diagnosed GD were entered into the case-control study. Individuals showing signs of GO at enrolment were excluded. During the two-year follow-up, eye signs were recorded every 3 months. Orbital DTPA uptakes on SPECT images were measured when entering the study and at the end of the follow-up period, or when clinical signs of GO developed, whichever occurred first. RESULTS: During the follow-up, 6 patients (22%) were diagnosed with GO. There was no significant difference between the initial DTPA uptakes of the patients with or without later developing GO (10.45±1.72 MBq/cm3 vs. 9.18±1.18 MBq/cm3 respectively). However, the DTPA uptakes of both GD groups (ie. with and without GO) were higher than that of the control group (7.45±1.36 MBq/cm3, p<0.05). CONCLUSIONS: We have shown that GD is accompanied by moderate orbital immune activity in GD patients without GO, irrespective of later development of GO. Why this orbital autoimmunity remains subclinical in the majority of the cases, and progresses into clinically detectable GO in others, remains unclear.

Thyroglobulin level at week 16 of pregnancy is superior to urinary iodine concentration in revealing preconceptual and first trimester iodine supply.

Pregnant women are prone to iodine deficiency due to the increased need for iodine during gestation. Progress has recently occurred in establishing serum thyroglobulin (Tg) as an iodine status biomarker, but there is no accepted reference range for iodine sufficiency during pregnancy. An observational study was conducted in 164 pregnant women. At week 16 of gestation urinary iodine concentration (UIC), serum Tg, and thyroid functions were measured, and information on the type of iodine supplementation and smoking were recorded. The parameters of those who started iodine supplementation (≥150 µg/day) at least 4 weeks before pregnancy (n = 27), who started at the detection of pregnancy (n = 51), and who had no iodine supplementation (n = 74) were compared. Sufficient iodine supply was found in the studied population based on median UIC (162 µg/L). Iodine supplementation ≥150 µg/day resulted in higher median UIC regardless of its duration (nonusers: 130 µg/L vs. prepregnancy iodine starters: 240 µg/L, and pregnancy iodine starters: 205 µg/L, p < .001, and p = .023, respectively). Median Tg value of pregnancy starters was identical to that of nonusers (14.5 vs. 14.6 µg/L), whereas prepregnancy starters had lower median Tg (9.1 µg/L, p = .018). Serum Tg concentration at week 16 of pregnancy showed negative relationship (p = .010) with duration of iodine supplementation and positive relationship (p = .008) with smoking, a known interfering factor of iodine metabolism, by multiple regression analysis. Serum Tg at week 16 of pregnancy may be a promising biomarker of preconceptual and first trimester maternal iodine status, the critical early phase of foetal brain development.