Serum Iodine Concentration Research Articles

Exploring the Correlation Between Varied Serum Iodine Nutritional Levels and Anti-Thyroglobulin Antibodies.

Iodine deficiency results in elevated thyroglobulin (Tg) concentrations, with high iodine Tg being more immunogenic than low iodine Tg. The study investigated the correlation between serum iodine concentration and thyroglobulin autoantibody (TgAb) levels across diverse iodine nutritional statuses as determined by urine iodine concentration (UIC). Demographic information was collected from 1,482 participants through a questionnaire. Blood and spot urine were collected to measure thyroid-stimulating hormone (TSH), TgAb, thyroid anti-peroxidase antibody (TPOAb), serum iodine (SIC), serum non-protein-bound iodine (snPBI), urine iodine (UIC), creatinine (UCr). The median UIC and SIC were 146.5μg/L and 74.9μg/L, respectively. A linear relationship was observed between SIC, snPBI, and serum-protein-bound iodine (sPBI) (P < 0.001). The 90% reference intervals for SIC, snPBI, and sPBI were 50.7-120.7μg/L, 21.9-52.9μg/L, and 19.7-77.9μg/L, respectively. The prevalence of elevated TgAb levels was significantly higher in women than in men (P < 0.001). Both low and high levels of snPBI and sPBI were associated with an increased risk of elevated TgAb levels. In women, the risk of positive TgAb in the group below the reference value of snPBI (OR = 2.079, 95%CI: 1.166, 3.705) and sPBI (OR = 2.578, 95%CI: 1.419, 4.684) was higher. In men, the risk of positive TgAb in the group below the reference value of SIC was higher (OR = 3.395, 95%CI: 1.286, 8.962). Iodine might exert an influence on TgAb levels through its binding to proteins, primarily Tg, thereby altering the iodine content of Tg. The interplay of gender factors further enhanced the risk of TgAb emergence.

Study of iodine transport and thyroid hormone levels in the human placenta under different iodine nutritional status.

Iodine and thyroid hormones (TH) transport in the placenta are essential for fetal growth and development, but there is little research focus on the human placenta. The research aimed to investigate iodine and TH transport mechanisms in the human placenta. The placenta was collected from sixty healthy pregnant women. Urinary iodine concentration (UIC), serum iodine concentration (SIC), placenta iodine storage (PIS) and the concentration of serum and placenta TH were examined. Five pregnant women were selected as insufficient intake (II), adequate intake (AI) and above requirements intake (ARI) groups. Localisation/expression of placental sodium/iodide symporter (NIS) and Pendrin were also studied. Results showed that PIS positively correlated with the UIC (R = 0·58, P < 0·001) and SIC (R = 0·55, P < 0·001), and PIS was higher in the ARI group than that in the AI group (P = 0·017). NIS in the ARI group was higher than that in the AI group on the maternal side of the placenta (P < 0·05). NIS in the II group was higher than that in the AI group on the fetal side (P < 0·05). In the II group, NIS on the fetal side was higher than on the maternal side (P < 0·05). Pendrin was higher in the II group than in the AI group on the maternal side (P < 0·05). Free triiodothyronine (r = 0·44, P = 0·0067) and thyroid-stimulating hormone (r = 0·75, P < 0·001) between maternal and fetal side is positively correlated. This study suggests that maternal iodine intake changes the expression of NIS and Pendrin, thereby affecting PIS. Serum TH levels were not correlated with placental TH levels.

Evaluation of dermal toxicity and toxicokinetics of povidone‑iodine in Göttingen minipigs

BackgroundPovidone‑iodine (PVP-I) is an effective and commonly used broad-spectrum antiseptic; limited information exists around its long-term safety and impact on endocrine disruption. We assessed the dermal toxicity and toxicokinetics following a once-daily application of 7.5% (w/v) and 10% (w/v) PVP-I in Göttingen Minipigs® for up to 39 weeks. MethodsAn in vivo study was conducted in male (n = 27) and female (n = 27) minipigs. Animals were randomized into untreated control, 7.5% and 10% PVP-I, and matching vehicle treatment groups. Animals were assessed for general in-life measurements, including skin irritation and organ weights. Serum samples were analyzed for PVP, total iodine, triiodothyronine [T3], thyroxine [T4], thyroid stimulating hormone [TSH], and toxicokinetic parameters. ResultsNeither 7.5% nor 10% PVP-I affected general in-life measurements. Increased mean thyroid gland absolute weights were noted with 7.5% and 10% PVP-I. Serum levels of PVP, T3, T4, and TSH in the 7.5% and 10% PVP-I treatment group animals were similar to those in vehicle treatment group animals. Mean total serum iodine concentration was 52- and 13-fold higher with 7.5% and 10% PVP-I, respectively, vs respective vehicle treatments. There was no dose-dependent increase in mean maximum serum concentration and area under the curve from 0 to 24 h for PVP, T3, T4, and TSH, nor accumulation of PVP, T3, T4, or TSH in the study. ConclusionOnce-daily dermal application of 7.5% and 10% PVP-I for up to 39 weeks was safe and well tolerated in Göttingen Minipigs® and was not associated with skin irritation, thyroid dysfunction, or endocrine disruption. As the anatomy and physiology of the minipig skin closely resembles that of human skin, the findings of this study suggest that 7.5% and 10% PVP-I may be translated into antimicrobial benefits for humans without the risk of endocrine disruption.

Serum iodine concentration and its associations with thyroid function and dietary iodine in pregnant women in the southeast coast of China: a cross-sectional study.

Iodine deficiency is a major public health problem in pregnant women. Serum iodine (SI) may represent a useful biomarker for iodine nutrition evaluation. We aimed to assess the relationship between serum iodine concentration (SIC) and urinary iodine concentration (UIC), dietary iodine, thyroid function, and thyroid diseases in pregnant women in the southeast coast of China, and to provide a normal reference range of SIC for pregnant women. A multistage random sampling method was used to select the study population. We collected urine and blood samples from pregnant women and determined UIC and SIC as well as thyroid function using Arsenic-Cerium Catalytic Spectrophotometry, inductively coupled plasma mass spectrometry, and Beckman Coulter Access2 chemiluminescent immunoanalyzer and kit, respectively, and administered a questionnaire on dietary iodine intake in pregnant women. There was a significant negative correlation between SI and thyroid-stimulating hormone (TSH) (r = -0.141) and a significant positive correlation between SI and free triiodothyronine (FT3) (r = 0.106), free thyroxine (FT4) (r = 0.236), triiodothyronine (TT3) (r = 0.229), total thyroxine (TT4) (r = 0.433), and dietary iodine intake (r = 0.068). There was a significant difference in SI levels of pregnancy between the second (78.13 μg/L) and third trimester (75.37 μg/L) (p = 0.018). SI levels between inadequate intake (74.58 μg/L) and appropriate intake (77.92 μg/L) groups were statistically different (p = 0.036). Low SIC was a risk factor for the development of hypothyroxinemia (adjusted OR = 3.14, 95% confidence interval: 1.75-5.66). The reference range for SIC in normal pregnant women is 45.03-112.44 μg/L. SI may be a composite indicator of iodine nutritional status and thyroid function.

Reference Intervals of Serum Iodine Concentration in Chinese Pregnant Women.

The study aims to establish trimester-specific reference ranges for serum iodine (SI) in Chinese pregnant women and explore its associations with maternal and infantile thyroid function. Apparently healthy pregnant women were enrolled during their first antenatal visit. Fasting venous and spot urine samples were collected for determining serum and urinary iodine (UI) levels by a validated inductively coupled plasma mass spectrometry. Serum free triiodothyronine (FT3), free thyroxine (FT4), thyrotropin (TSH), and neonatal TSH levels were tested by electro-chemiluminescent assay. The reference ranges of SI were established by percentile method and reported as 2.5-97.5%. ROC analysis was applied to compare the discriminative ability of SI, UI, and UI to urinary creatine ratio (UI /UCr) in early pregnancy for various thyroid conditions. The trimester-specific reference ranges of SI for Chinese pregnant women were 60.91-114.53 μg/L for the first trimester (T1, n = 1029), 54.57-103.42 μg/L for the second trimester (T2, n = 379), and 52.03-110.40 μg/L for the third trimester (T3, n = 455). Maternal SI at T1 but not UI and UI/UCr was significantly correlated with FT3 (r = 0.393, P < 0.001), FT4 (r = 0.637, P < 0.001), and TSH (r = -0.299, P<0.001). Maternal SI change% from T1 to T2 (but not SI change% from T1 to T3) had marginal correlation with neonatal TSH (r=-0.106, P=0.046). ROC analysis showed that maternal SI at T1 had better predictability for several thyroid conditions than UIC and UI/UCr.

The efficacy of iodinated ethyl esters of safflower seed oil (Carthamus tinctorius L.) in the control of iodine deficiency in sheep

Iodine is an essential component of the thyroid gland hormones (T3 and T4), necessary for mammalian life. Iodine deficiency leads to inadequate thyroid hormone production, and all the consequences of iodine deficiency stem from the associated hypothyroidism. Iodized oil is made by treating a fatty vegetable oil with iodine or hydriodic acid and is an effective long-term means of iodine supplementation. The type and fatty acids profile in the parent oil, as well as the way iodine is trapped, affect the physicochemical properties and effectiveness of the product. This research was conducted to study the effect of iodinated safflower oil on preventing iodine deficiency disorders (IDD) in livestock, compared with a commercial iodine supplement. Iodinated fatty acid ethyl esters prepared from safflower seed oil (IFAEESSO). Thirty Farahani ewes with a history of iodine deficiency were divided into three groups, including control and two treatment groups. The treatment groups received 390 mg of iodine by an intramuscular injection of 1.26 ml of IFAEESSO (n = 10) or 1.5 ml of Depodine® (n = 10), respectively. Serum iodine, thyrotropin stimulating hormone (TSH), T3 and T4 concentrations were assayed at baseline and every 30-day intervals over six months period. Iodine supplementation resulted in a significant increase in serum inorganic iodine over five months with Depodine and IFAEESSO (P < 0.01). Serum T3 and T4 concentrations also increased in treatment groups (P < 0.01), while the concentration of TSH didn’t change. The mean T4 and T3 concentrations were 3.16 μg /dl and 53.89 ng /dl in the control group, which increased to 3.50 μg /dl and 58.88 ng/dl for Depodine and 3.88 μg /dl and 63.55 ng/dl for IFAEESSO, respectively. The serum inorganic iodine and thyroid hormone concentrations were significantly higher in the IFAEESSO group than in the Depodine group (P < 0.01). IFAEESSO is an effective supplement against IDD and more efficient than that of Depodine to increase serum iodine concentration, and thyroid hormone production.

Associations of Maternal Serum Iodine Concentration with Obstetric Complications and Birth Outcomes—Longitudinal Analysis Based on the Huizhou Mother–Infant Cohort, South China

This study aimed to explore the temporal associations between maternal serum iodine concentration (SIC) and common pregnancy outcomes in Chinese women. Eligible singleton pregnant women aged 20–34 years were selected, and their fasting blood samples were collected during early (T1, n = 1101) and mid-pregnancy (T2, n = 403) for SIC testing by inductively coupled plasma mass spectrometry. Multivariable linear regression indicated that log10SIC at T1 (β = −0.082), T2 (β = −0.198), and their % change (β = −0.131) were inversely associated with gestational weight gain (GWG, all p &lt; 0.05). Maternal log10SIC at both T1 (β = 0.077) and T2 (β = 0.105) were positively associated with the Apgar score at 1 min (both p &lt; 0.05). Women in the third quartile (Q3) of SIC at T1 had a lower risk of small for gestational age (SGA, OR = 0.405, 95% CI: 0.198–0.829) compared with those in Q4. Restricted cubic spline regression suggested a U-shaped association between SIC and SGA risk, and SIC above 94 μg/L at T1 was the starting point for an increased risk of SGA. The risk of premature rupture of membrane (PROM) increased by 96% (OR = 1.960, 95% CI: 1.010–3.804) in Q4 compared to that in Q1. Our longitudinal data from an iodine-replete region of China indicated that high maternal SIC could restrict GWG and improve Apgar scores at delivery, but might increase the risk of SGA and PROM.

A Cohort Study on the Effects of Maternal High Serum Iodine Status During Pregnancy on Infants in Terms of Iodine Status and Intellectual, Motor, and Physical Development.

The objective of the present study was to explore the effects of maternal iodine excess during pregnancy on infants' neurodevelopment and physical development. A total of 143 mother-child pairs were enrolled in this cohort study. Maternal blood samples were collected during the obstetric examination. A mother-child questionnaire survey was conducted, and infants' blood samples were collected during the newborn physical examination. Infants' single-spot urine samples were collected, and intellectual, motor, and physical development were assessed at 2months of age. The median (IQR) maternal serum iodine concentrations (SICs) in the first, second, and third trimesters of pregnancy were 91.2 (74.4, 102.2) μg/L, 81.2 (70.6, 94.8) μg/L, and 82.0 (68.9, 100.3) μg/L, respectively. In the first trimester of pregnancy, infants' psychomotor developmental index (PDI), body mass index (BMI) and weight-for-length Z score (WLZ) were higher with maternal suitable SIC (40 ~ 92μg/L) than with maternal excess SIC (P < 0.05). Infants' PDI, BMI, weight-for-age Z score (WAZ) and WLZ were negatively correlated with maternal SIC (P < 0.05). Maternal excess SIC had a slightly negative effect on infants' MDI (OR = 1.304, P = 0.035, 95% CI = 1.019 ~ 1.668), PDI (OR = 1.124, P = 0.001, 95% CI = 1.052 ~ 1.200) and BMI (OR = 0.790, P = 0.005, 95% CI = 0.669 ~ 0.933). In the third trimester, infants' length-for-age Z score (LAZ) was higher with maternal high SIC (> 92μg/L) (P = 0.015), and maternal SIC was positively correlated with infants' urine iodine concentration (UIC) (P = 0.026). Maternal iodine excess in the first trimester had a slightly negative effect on infants' intellectual, motor, and physical development. In the third trimester, maternal iodine excess only may have a positive impact on infants' height. Additionally, maternal iodine status was closely related to infants' iodine status.

Nomogram Model Based on Iodine Nutrition and Clinical Characteristics of Papillary Thyroid Carcinoma to Predict Lateral Lymph Node Metastasis.

Preoperative evaluation of lateral lymph node metastasis (LLNM) in patients with papillary thyroid carcinoma (PTC) has been one of the major clinical challenges. This study aims to develop and validate iodine nutrition-related nomogram models to predict lateral cervical lymph node metastasis in patients with PTC. This is a retrospective study. Urinary iodine concentration (UIC) and serum iodine concentration (SIC) were measured in 187 LLNM patients and 289 non-LLNM (NLLNM) patients. All patients were randomized 3:1 into the training cohort (n = 355) and the validation cohort (n = 121). Using logistic regression analysis, we analyzed the influence of iodine nutrition-related factors and clinicopathological characteristics on LLNM in PTC patients. Lasso regression method was used to screen risk factors and construct a nomogram for predicting LLNM. The receiver operating characteristic curve (ROC curve), calibration curve, and decision curve analysis (DCA) of the nomogram models were carried out for the training and validation cohorts. Gender, SIC, smoking history, drinking history, family history of PTC, multifocality, bilateral or unilateral tumors, TSH, Tg, and tumor size were included in the nomogram model predicting LLNM, with an area under the curve (AUC) of .795. The nomogram model showed good calibration and clinical benefit in both the training and validation cohorts. The nomogram model based on iodine nutrition and other clinicopathological features is effective for predicting the lateral lymph node metastasis in PTC patients.

Study on the Relationship Between Serum Iodine and Thyroid Dysfunctions: a Cross-Sectional Study.

The relationship between serum iodine (SIC) and thyroid dysfunctions in adults is poorly understood, and this study aimed to explore their relationship. A total of 1320 participants were included in the final analysis. We collected basic demographic information, blood, and spot urine samples to determine serological indices and iodine nutritional status. The median (IQR) of urinary iodine (UIC)/urinary creatinine (UCr), UIC, SIC were 138.1 (91.1, 207.6) μg/g, 155.8 (94.5, 211.1) μg/L, and 70.6 (59.8, 83.9) μg/L, respectively. The 90% reference ranges for UIC/UCr and SIC were 66.5-349.8mg/g and 49.3-97.1μg/L. SIC was positively correlated with UIC and UIC/UCr. The prevalence of overt hypothyroidism and subclinical hypothyroidism in female was significantly higher than that in male (P = 0.02, P = 0.002). In male, subjects above the upper reference value of SIC (97.1μg/L) had a higher risk of subclinical hyperthyroidism (OR = 4.46, 95% CI: 1.29, 12.8) and overt hypothyroidism (OR = 5.59, 95% CI: 1.88, 6.42). In female, subjects below the lower reference value of SIC (49.3μg/L) had a higher risk of overt hypothyroidism (OR = 2.18, 95% CI: 1.10, 4.06), TgAb positive (OR = 1.97, 95% CI: 1.15, 3.32) and TPOAb positive (OR = 2.48, 95% CI: 1.41, 4.26). In conclusion, serum iodine can be used as an indicator to evaluate iodine nutritional status and thyroid dysfunctions. Higher serum iodine concentration was associated with an increased risk of subclinical hyperthyroidism and overt hypothyroidism in men; lower serum iodine concentration was associated with an increased risk of overt hypothyroidism and positive TgAb and TPOAb in women.

Iodine Metabolism and Thyroid Function During the Perinatal Period: Maternal-Neonatal Correlation and Effects of Topical Povidone-Iodine Skin Disinfectants.

An adequate maternal iodine intake during pregnancy and lactation is essential for growth and mental development in fetuses and newborns. There are limited data on perinatal iodine metabolism in mothers and infants, as well as the effect of povidone-iodine (PVP-I) antiseptics used in cesarean delivery. The urinary iodine concentration (UIC), serum iodine, thyrotropin (TSH), free thyroxine (FT4), and breast milk iodine concentration (BMIC) were measured consecutively in a total of 327 mothers and 249 term-infants in two prospective studies. The maternal median UIC was 164μg/L in the third trimester, increased to 256μg/L at 44h after birth, and then decreased to 116μg/L 1month later. The BMIC on the 4th and 32th postpartum days was 17.6 and 13.5μg/100g, respectively. In neonatal infants born to the mothers unexposed to PVP-I, the median UIC was 131μg/L in the first voiding urine and increased to 272μg/L on day 4 and then slightly decreased to 265μg/L on day 28 suggesting sufficient iodine reserve at birth. PVP-I antiseptics containing 1g of iodine for skin preparation at cesarean delivery transiently increased maternal serum iodine concentration (1.9-fold), UIC (7.8-fold) at 41 h after surgery and BMIC, while it had little effect on maternal TSH, FT4, and neonatal UIC, TSH, or FT4. The iodine status of pregnant women and their infants was adequate in this population; however, the UIC in lactating mothers at one postpartum month was low enough to suggest iodine deficiency or near iodine deficiency. Further studies are necessary.

The Thyroid Condition and Residual Clinical Signs in 31 Existing Endemic Neurological Cretins After 42 Years of Iodine Supplementation in China.

BackgroudEndemic cretinism is the most severe manifestation among the iodine deficiency-related disorders. The clinical status of the cretins may be modified subsequently by the duration and severity of the disease. We aimed to reassess the clinical status and thyroid function of 31 surviving “neurological cretins” after 42 years of iodine supplementation in a historically severely iodine deficiency area of China.MethodsIt was a cross-sectional study in design and we investigated all 31 surviving neurological cretins and 85 controls. A detailed neurological examination was conducted on each patients. All the participants were given a questionnaire and underwent B-mode ultrasonography of the thyroid. The serum levels of thyroid hormones, thyroid antibodies, serum iodine concentration (SIC) and urine iodine concentration (UIC) were measured.ResultsThe neurological cretins had shorter stature than that of the control. Neurological damage is still present in patients with cretinism. The prevalence of subclinical hypothyroidism and thyroid nodule in the cretins was significantly higher (χ2 =4.766, P=0.029 and χ2 =17.077, P<0.0001, respectively) compared with the control. After adjusting for confounding factors, endemic neurocretinism was found to be an independent risk factor for subclinical hypothyroidism (OR=4.412; 95% CI: 1.358–14.334; P=0.014) and thyroid nodule (OR=6.433; 95% CI: 2.323–17.816; P<0.0001).ConclusionsIodine supplementation after birth does not reverse the neurological damage that results from maternal/foetal hypothyroidism in utero and is subsequently manifested as neurological cretinism. There is a cross-sectional association between endemic neurocretinism and subclinical hypothyroidism and thyroid nodule.

The study of blood serum trace elements in comparison with the structural and functional characteristics of goiter and the carriage of antithyroid antibodies in some regions of Russia

The study of the sufficiency with essential trace elements in the context of thyroid pathology is especially relevant, since the development and progression of thyroid diseases have various pathogenetic mechanisms, which largest proportion is provoked by insufficient intake of key trace elements, primarily iodine. The aim of the research was obtaining primary data on the sufficiency with essential trace elements of the population in the some regions of the Russian Federation, comparing the data obtained with the prevalence of goiter and the carriage of antibodies to thyroid peroxidase (AT-TPO). Material and methods. The Cross-Sectional Population Study was conducted in medical institutions of the Republics of Crimea, Republics of Tuva and Bryansk region (persons applied for outpatient consultations). The scope of the study was 387 people aged 18 to 65 years (the average age was 40±5 years). All of them underwent: collection of medical history, endocrinologist examination with palpation of the thyroid gland (TG), ultrasound examination of TG, blood sampling to assess the levels of thyroid-stimulating hormone (TSH), AT-TPO, iodine, selenium, zinc. Ultrasound of the TG was performed in the supine position using a portable ultrasound machine LOGIQe (China) with a multi-frequency linear probe 10-15 MHz. During the study, the volume of the thyroid gland, the presence of nodular formations and their characteristics according to the TIRADS classification, TG structure and its echogenicity were assessed. Iodine, selenium and zinc level were measured using tandem mass spectrometry with ionization in inductively coupled plasma (Agilent 8900 ICP-MS Triple Quad). TSH and Ab-TPO were determined by chemiluminescent immunoassay on the Architect i2000 automatic analyzer. Results. All regions are comparable in terms of iodine availability, but differ in the severity of natural iodine deficiency. The median concentration of iodine in blood serum practically coincided in all three regions, amounting to 39.8 μg/l in the Republic of Crimea; 38.8 μg/l in the Republic of Tyva and 43.4 μg/l in the Bryansk region. Comparing these results with foreign data, as well as with our results on urinary iodine level, obtained by routine cerium-arsenite method, we can assume that iodine content in blood serum corresponded to the lower limit of the normal target values. The median concentration of selenium in blood serum also practically coincided in all three regions, amounting to 68.2, 72.1 and 62.8 μg/l, respectively, and probably meets the criteria for optimality. The median serum concentration of zinc in Bryansk region residents corresponded to a deficiency (491.3 μg/l) and was significantly lower compared to the indicator in the Republics of Crimea and Tyva (1633.2 and 1667.6 μg/l, respectively, values above optimal). Among the examined, the proportion of people with AB-TPO carriership was 23.5% (Republic of Crimea - 20.9%, Republic of Tuva - 26.4%, Bryansk region - 20.7%), with impaired thyroid function - 9.6% (6.2% - hypothyroidism, 3.4% - thyrotoxicosis). The frequency of goiter varied from 10 to 13.8%. There were no significant differences in the frequency of occurrence, ultrasonic characteristics of goiter and thyroid nodules by regions. Conclusion. However, the results obtained do not allow to unequivocally judge the absence of micronutrient deficiency in the population of the regions of the Russian Federation, since used the ICP-MS method requires the development of our own reference values of trace elements; in the absence of the latter, data from similar foreign studies were taken as standards. In addition, in further studies it will be important to take into account additional criteria for assessing trace element deficiency, for example, activity of superoxide dismutase and alkaline phosphatase as indirect markers of zinc deficiency, etc. Correlation between blood serum concentration of trace elements and the frequency and structural characteristics of goiter, the carriage of Ab-TPO, and dysfunction of the TG was not revealed.

Exploration of the optimal range of urinary iodine concentration in Chinese pregnant women in mildly iodine-deficient and -sufficient areas.

There is some uncertainty about the optimal ranges for urinary iodine concentration (UIC) during pregnancy. This study aimed to explore associations between maternal UIC and thyroid function in iodine sufficient and mildly iodine deficient areas. It was a cross-sectional study in which 1461 healthy pregnant women were enrolled to collect their blood and urine samples during their routine antenatal care in Tianjin and Wuqiang, China. Wuqiang was a mildly iodine-deficient region, while Tianjin was iodine sufficient. UIC, free triiodothyronine (FT3), free thyroid hormone (FT4), thyroid stimulating hormone (TSH), thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TgAb), serum iodine concentration (SIC) including total serum iodine concentration (tSIC) and non-protein bound serum iodine concentration (nbSIC) were assessed during the routine antenatal care visits. The median UIC in pregnant women was 174 (113, 249) μg/L in Tianjin and 111 (63, 167) μg/L in Wuqiang, respectively. Compared with Tianjin, UIC, FT3 and TSH were lower, and FT4, tSIC, nbSIC, rates of TPOAb and TgAb positivity and the thyroid dysfunction rate (TDR) were higher in Wuqiang (P < 0.001). FT3, FT4, tSIC and nbSIC increased during pregnancy in Tianjin with increasing UIC, while only FT3 and nbSIC increased in Wuqiang (P < 0.05). In Tianjin, the TDR increased with UIC and peaked at UIC ≥ 500μg/L (P = 0.002), while in Wuqiang, the TDR showed a weak "U-shaped" relationship with UIC and the rate was lowest with UIC 100-149μg/L. In iodine-deficient areas, there was a lower TDR in pregnant women with UIC 100-149μg/L. We suspected that the optimal UIC criteria recommended by WHO may be a little high for pregnant women in mild-to-moderate iodine-deficient countries.

High Iodine Nutrition May Be a Risk Factor for Cervical Lymph Node Metastasis in Papillary Thyroid Cancer Patients

Purpose: The aim of this study was to retrospectively identify the effect of iodine on the papillary thyroid cancer (PTC) process and investigate the risk clinicopathologic characteristics of cervical lymph node metastasis (CLNM) for achieving a better preventive strategy of PTC. Methods: Totally 187 patients with CLNM and 279 without CLNM (NCLNM) were enrolled, and their urinary iodine concentration (UIC) and serum iodine concentration (SIC) were measured. Logistic regressions were used to reveal the effects of iodine nutrition on the CLNM status of PTC. Results: The levels of thyroid-stimulating hormone (TSH) and thyroglobulin (TG) were higher in the CLNM group than in the NCLNM group. UIC and SIC were positively correlated, and both of them were correlated with TSH, free thyroxine, and TG. The proportions of UIC >300 μg/L and of SIC >90 μg/L were higher in the CLNM than in the NCLNM. Logistic analysis showed that SIC >90 μg/L was an independent predictor for CLNM in PTC. Additionally, age ≥45, female, TG, multifocality, and diameter of cancer invasion >1 cm also affected CLNM status in PTC, and their logistic regression model showed a certain diagnostic accuracy (area under the receiver-operating characteristic curve = 0.72). Conclusions: Relatively high iodine nutrition seemed to be a significant risk factor for the occurrence of CLNM in PTC and may promote lymphatic metastasis in PTC.

The Impact of Preconceptional Hysterosalpingography with Oil-based Contrast on Maternal and Neonatal Iodine Status.

The objective of this study is to investigate the impact of preconceptional exposure to oil-based iodinated contrast in the hysterosalpingography (HSG) on pregnant women and their offspring's iodine status, thyroid function, and the outcomes of pregnancy. A cross-sectional evaluation of iodine status was performed on pregnant women with the preconceptional experience of ethiodized-oil HSG. For those found to have iodine excess (with serum iodine concentration (SIC) > 92 μg/L), a prospective follow-up was conducted until termination of the pregnancy or 1 week postpartum. Among 70 of 425 pregnant women with preconceptional ethiodized-oil HSG, iodine excess was initially confirmed in 38 (54.3%), with an elevated SIC (294.00 μg/L [142.00, 123.20]) and urinary iodine-to-creatinine ratio (UI/Cr) (830.00 μg/g Cr [437.50, 255.30]), both higher than the normative data (P = 0.000, P = 0.000). Subsequent follow-up in pregnancy showed a downward trend in both SIC and UI/Cr. Thirty-four women delivered healthy neonates at full term, though the other 4 cases of premature birth, abnormal fetal karyotype, spontaneous abortion, and neonatal cardiac defect were reported. After delivery, the iodine concentration in maternal breast milk and neonatal urine was 584.50 μg/L [328.50, 1507.50] and 424.00 μg/L [277.00, 657.50], respectively, both higher than normative data (P = 0.001, P = 0.015). For thyroid evaluation, 25 cases (65.79%) of clinical or subclinical hypothyroidism and 2 cases (5.26%) of thyrotoxicosis were confirmed in women with iodine excess. Neither goiter nor thyroid dysfunction was detected in any offspring. Preconceptional exposure to oil-based contrast in HSG might exert a far-reaching impact on maternal and offspring iodine status, and tend to result in increased risk of maternal thyroid dysfunction.

The Status of Iodine Nutrition after Removing Iodized Salt in High Water Iodine Regions: a Cross-sectional Study in China.

Currently, the removal of iodized salt is carried out in high water iodine regions. The present situation of iodine nutrition and the prevalence of thyroid diseases in such regions have not been clearly elucidated. This study aimed to figure out these problems to help render effective measures for cases of abnormal iodine nutrition status. A cross-sectional study was carried out in four areas of Jining and Heze, Shandong Province, China, with different water iodine concentrations (WIC). In total, 1344 adults were enrolled in this study, and data related to their iodine nutrition, thyroid function, and thyroid ultrasonography were collected. Subjects were grouped according to WIC, urine iodine concentration (UIC), serum iodine concentration (SIC), and combined UIC and SIC for analysis. Iodine levels were in excess in the 100 μg/L ≤ WIC < 300 μg/L and WIC ≥ 300 μg/L areas. Compared with the control WIC group (10-100 μg/L), the WIC ≥ 300 μg/L group had a higher prevalence of thyroid autoimmunity (TAI, 21.25% vs. 13.19%, P<0.05), subclinical hypothyroidism (SH, 20.20% vs. 11.96%, P < 0.05), thyroid nodules (TN, 31.75% vs. 18.71%, P < 0.05), and thyroid dysfunction (23.62% vs. 12.26%, P < 0.05). Compared with the UIC control group (100-300 μg/L), high UIC group (≥ 800 μg/L) had a higher prevalence of TN (33.75% vs. 21.14%, P < 0.05) and thyroid dysfunction (25% vs. 14.47%, P < 0.05). Next, compared with the control SIC group (50-110 μg/L), high SIC group (≥ 110 μg/L) had a higher prevalence of TAI (33.80% vs. 14.47%, P < 0.05), SH (23.94% vs. 14.30%, P < 0.05), and thyroid dysfunction (33.80% vs. 15.29%, P < 0.05). Finally, subjects with the highest UIC and the highest SIC also had a higher prevalence of TAI (25.92% vs. 10.97%, P < 0.05), SH (23.45% vs. 10.97%, P < 0.05), TN (34.56% vs. 15.85%, P < 0.05), and thyroid dysfunction (27.16% vs. 13.41%, P < 0.05) than subjects with middle iodine levels. The iodine nutrition of subjects in the WIC ≥ 300 μg/L areas was still in excess after removing iodized salt from their diets. High levels of iodine also increased the prevalence of TAI, SH, TN, and thyroid dysfunction in those areas. Simply removing iodized salt may not be sufficient for high water iodine regions.

Prediction of ipsilateral lateral cervical lymph node metastasis in papillary thyroid carcinoma: a combined dual-energy CT and thyroid function indicators study

BackgroundPredicting the possibility of ipsilateral lateral cervical lymph node metastasis (ipsi-LLNM) was crucial to the operation plan for patients with papillary thyroid carcinoma (PTC). This study aimed to investigate the independent risk factors for ipsi-LLNM in PTC patients by combining dual-energy computed tomography (DECT) with thyroid function indicators.MethodsWe retrospectively enrolled 406 patients with a pathological diagnosis of PTC from Jan 2016 to Dec 2019. Ensure the DECT images were clear and the thyroid function indicators were complete. Univariate and multivariate logistic analyses explored the independent risk factors for ipsi-LLNM. To evaluate the cutoff value of each risk factor by using receiver operating characteristic (ROC) curves.ResultsA total of 406 patients with PTC were analyzed, including 128 with ipsi-LLNM and 278 without ipsi-LLNM. There were statistical differences of parameters between the two groups (P < .0001), including serum Tg, Anti-Tg, Anti-TPO, the volume of the primary lesion, calcification, extrathyroidal extension (ETE), and iodine concentration (IC) in the arterial and the venous phases. Independent risk factors for ipsi-LLNM included serum Tg, Anti-Tg, ETE, and IC in the arterial and the venous phases (P < .05). The combined application of the above independent risk factors can predict the possibility of ipsi-LLNM, with an AUC of 0.834. Ipsi-LLNM was more likely to occur when the following conditions were met: with ETE, Tg > 100.01 ng/mL, Anti-Tg > 89.43 IU/mL, IC in arterial phase > 3.4 mg/mL and IC in venous phase > 3.1 mg/mL.ConclusionsThe combined application of DECT quantitative parameters and thyroid function indicators can help clinicians accurately predict ipsi-LLNM before surgery, thereby assisting the individualized formulation of surgical procedures.

An evaluation of urine and serum iodine status in the population of Tibet, China: No longer an iodine-deficient region.

Iodine is a critical trace element for the synthesis of thyroid-related hormones, and either low or high iodine status can lead to thyroid dysfunction. This study aimed to evaluate the iodine status of the Tibetan population. From September 2016 to August 2018, we enrolled 1499 healthy adults from three areas of varying altitudes in Tibet. Urine iodine concentrations (UICs), adjusted UICs, and serum iodine concentrations (SICs) were measured using inductively coupled plasma mass spectrometry. The median UIC, adjusted UIC, and SIC was 137.9 μg/L, 118.4 µg/gCr, and 58.3 μg/L, respectively. Of the participants, 30.4% had UICs <100 µg/L, 63.0% had UICs ranging from 100 to 300 µg/L, and 9.6% had UICs >300 µg/L. The correlation between UIC, adjusted UIC, and SIC was good (r > 0.65, P < 0.01). The SICs were more stable than the UICs, and were not associated with age or sex. The prevalence of clinical hyperthyroidism, clinical hypothyroidism, subclinical hyperthyroidism, subclinical hypothyroidism, positive thyroid peroxide antibody, positive thyroglobulin antibody, either positive and both positive was 0.5%, 1.3%, 1.7% and 17.9%, 9.3%, 6.5%, 12.5%, and 2.5%, respectively. The prevalence of almost all thyroid disorders was higher in women than in men. This multicenter cross-sectional study found that the human iodine status of adults in Tibet was considered adequate, based on the World Health Organization's criteria.

Distributions of serum thyroid-stimulating hormone in 2020 thyroid disease-free adults from areas with different iodine levels: a cross-sectional survey in China.

The aim of the present study was to describe the distributions of serum thyroid- stimulating hormone (TSH) levels in thyroid disease-free adults from areas with different iodine levels in China. Meanwhile, we aimed to evaluate the influence of age and gender on the distribution of TSH, assess the relationship between concentrations of TSH and free thyroxine (FT4), and analyze the factors that may affect TSH levels. 2020 adults were included from April 2016 to June 2019. Urinary iodine concentration, serum iodine concentration, serum TSH, FT4, free triiodothyronine, thyroid peroxidase antibodies and thyroglobulin antibodies were measured, and thyroid ultrasonography was performed. The median of TSH in iodine-fortification areas (IFA), iodine-adequate areas (IAA), iodine-excessive areas (IEA) were 2.32, 2.11 and 2.34mIU/L, respectively. Serum TSH concentrations were significantly higher in IFA and IEA than that in IAA (p = 0.005 and < 0.0001). The TSH values of most adults were distributed within the range of 1.01-3.00 mIU/L with the same trend in three groups. In our study, TSH levels did not change with age, and the TSH level of females was higher than that of males (p < 0.0001). There was a negative correlation between FT4 and TSH in IAA (r = - 0.160, p < 0.0001) and IEA (r = - 0.177, p < 0.0001), but there was no correlation between FT4 and TSH in IFA (r = - 0.046, p = 0.370). BMI, smoking status, education levels, and marital status were associated with TSH. Our study provides a basis for establishing the reference intervals of TSH in different iodine level areas.