Relationship Between Urinary Iodine Concentration and the Prevalence of Thyroid Nodules and Subclinical Hypothyroidism.

The aim of the study was to investigate the iodine intake in the resident population in Xi'an and analyze the relationship between iodine nutritional status and the prevalence of subclinical hypothyroidism and thyroid nodules (TNs). A total of 2507 people were enrolled in Xi'an. Venous serum thyroid stimulating hormone (TSH), thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb), urinary iodine concentration (UIC), and thyroid ultrasonography were collected. Patients with abnormal TSH were checked for free thyroxine (FT4) and triiodothyronine (FT3). Adults in Xi'an had median UICs of 220.80 µg/L and 178.56 µg/l, respectively. A sum of 16.78% of people had subclinical hypothyroidism. Both iodine excess and iodine deficit increased the frequency of subclinical hypothyroidism. The lowest was around 15.09% in females with urine iodine levels between 200 and 299 µg/l. With a rate of 10.69%, the lowest prevalence range for males was 100-199 µg/l. In Xi'an, 11.37% of people have TNs. In comparison to other UIC categories, TN occurrences were higher in females (18.5%) and males (12%) when UIC were below 100 µg/l. In conclusion, iodine intake was sufficient in the Xi'an area, while the adults' UIC remains slightly higher than the criteria. Iodine excess or deficiency can lead to an increase in the prevalence of subclinical hypothyroidism. Patients with iodine deficiency are more likely to develop TNs.

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.

Prevalence of thyroid dysfunction in postpartum women with suboptimal iodine and selenium and adequate iron status.

OBJECTIVE: Postpartum women experience thyroid dysfunction at twice the prevalence of the general population. Adequate biosynthesis of thyroid hormones depends on three trace elements: iodine, selenium and iron. This study aimed to investigate thyroid dysfunction within a cohort of women at six months postpartum in relation to iodine, selenium and iron status. DESIGN: This cross-sectional study was part of an observational longitudinal cohort Mother and Infant Nutrition Investigation; data obtained at six months postpartum are reported. SUBJECTS: Mother-infant pairs (n = 87) were recruited at three months postpartum and followed up at six months postpartum (n = 78). MEASUREMENTS: Thyroid hormones (free triiodothyronine, free thyroxine, thyroid-stimulating hormone) and thyroid peroxidase antibodies were measured. Urinary iodine concentration, breast milk iodine concentration, serum thyroglobulin, plasma selenium, serum ferritin and serum soluble transferrin receptors were determined. Nonparametric data were expressed as median (25th, 75th percentile). RESULTS: Thyroid dysfunction was found in 18% of women, and 4% of women had iron deficiency. Median urinary iodine concentration was 85 (43, 134) µg/L, median breast milk iodine concentration was 59 (39, 109) µg/L, and median serum thyroglobulin at 11.4 (8.6, 18.6) µg/L, indicating iodine deficiency. Median plasma selenium concentration was 105.8 (95.6, 115.3) µg/L. Women with marginally lower plasma selenium concentration were 1.12% times more likely to have abnormal TSH concentrations (p = .001). CONCLUSIONS: There was a high prevalence of thyroid dysfunction. Plasma selenium concentration was the only significant predictor of the likelihood that women had thyroid dysfunction within this cohort, who were iodine deficient and mostly had adequate iron status. Strategies are required to improve both iodine and selenium status to better support maternal thyroid function.

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

PURPOSE: 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. METHODS: 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. RESULTS: The median of TSH in iodine-fortification areas (IFA), iodine-adequate areas (IAA), iodine-excessive areas (IEA) were 2.32, 2.11 and 2.34 mIU/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. CONCLUSION: Our study provides a basis for establishing the reference intervals of TSH in different iodine level areas.

Combined ionized calcium and PTH evaluation in the management of post-thyroidectomy hypocalcemia.

BACKGROUND: The aim of our study was to investigate the postoperative course of calcium and parathyroid hormone (PTH) levels after total thyroidectomy to define a proper and low cost protocol. METHODS: We studied 144 patients who underwent total thyroidectomy between 2007 and 2010. Ionized calcium was determined preoperatively and on day 1 (POD1), day 2 (POD2) and day 7 (POD7) postoperatively; PTH preoperatively and on POD7. Patients with ionized calcium ≤1.11 mmol/L were considered hypocalcemic and treated only if symptoms, ≤1 mmol/L were treated in all cases. RESULTS: Ionized calcium and PTH declined postoperative in all patients compared to preoperative levels (P=0.000). Ionized calcium increased on POD7 compared to POD1 and POD2 (P=0.000). All hypocalcemic untreated 30 patients returned normocalcemic on POD7. Thirty-eight hypocalcemic patients were treated but 23 (61%) safely suspended therapy on POD7. We tested PTH and ionized calcium as independent factors of prolonged hypocalcemia (that required therapy beyond 7 days) with the following results (sensitivity, specificity, positive predictive value, negative predictive value and overall accuracy): PTH ≤11 pg/mL (80%, 100%, 100%, 96% and 97%, respectively), ionized calcium ≤1.11 mmol/L (80%, 88%, 59%, 95%, and 87%, respectively) and ionized calcium ≤1 mmol/L (28%, 100%, 100%, 87% and 88%, respectively). CONCLUSIONS: Our data show that our protocol, including serum ionized calcium on 1st, 2nd, 7th days and PTH on 7th day after surgery, is safe and low cost and therefore may be useful in the post-surgical management of total thyroidectomy.

Serum Iodine and Breast Cancer Risk: A Prospective Nested Case-Control Study Stratified for Selenium Levels.

BACKGROUND: Iodine has been suggested to protect against breast cancer, but there are no epidemiologic studies on individual risk. An interesting finding is that in areas where the exposure to both selenium and iodine are high (e.g., Japan), the risk of breast cancer is lower than in areas where selenium is high and iodine low (e.g., United States), or in areas where both are low (e.g., Northern Europe). The aim of this study was to investigate the association between prediagnostic serum iodine levels and subsequent breast cancer risk, and to investigate if this potential association was modified by selenium levels. METHODS: The Malmö Diet and Cancer Study provided prediagnostic serum samples and the current analysis included 1,159 breast cancer cases and 1,136 controls. Levels of baseline serum iodine and selenium were analyzed. A logistic regression analysis yielded ORs with 95% confidence intervals adjusted for potential confounders. RESULTS: There was no evidence of an overall association between iodine levels and risk of breast cancer. Among women with high selenium levels (above the median), high iodine levels were associated with a lower risk of breast cancer; the OR for above versus below the median was 0.75 (0.57-0.99). The corresponding OR for women with low selenium was 1.15 (0.87-1.50), and the P interaction was 0.06. CONCLUSIONS: The combination of high serum iodine levels and high selenium levels was associated with a lower risk of breast cancer. IMPACT: A high iodine and selenium exposure may decrease the risk of breast cancer.

Auto regulatory capacity of the thyroid gland after numerous iodinated contrast media investigations.

Excess of iodine may interfere with thyroid function. It is unclear to what extent the thyroid function is disturbed by repeated infusion of iodide contrast agent (IC) used during X-ray examinations. Thyroid function tests free T4 (FT4), free FT3 (FT3), thyroid-stimulating hormone (TSH), TSH receptor antibodies (TRAb) and thyroid peroxidase antibodies (TPO-Ab) were measured in a group of Norwegian patients with an assumed normal iodine balance before, 1 and 6 weeks after IC infusion. Forty patients (19 females and 21 men) referred for routine CT were included. Thirty two out of 40 patients had previously undertaken IC investigations. The mean TSH concentration was 2.1 mIU/l ± 1.7 at the baseline, increased to 2.9 ± 2.5 after 1 week (p < .001), and reverted to nearly initial values 1.4 ± 0.8 after 6 weeks. Initially the mean FT4 was 14.1 pmol/l ± 1.9 FT4, reduced to 13.3 pmol/l ± 2.5 (p = .009) after 1 week, and returned to 14.0 pmol/l ± 2.5 after 6 weeks, comparable to the initial values (p > .05). FT3 levels did not change during the period. There was no relationship between FT4, or TSH and age, gender, cancer/not cancer, number or frequency of earlier IC investigations. In conclusion, IC induces changes in thyroid function tests, however, they return to normal levels after 6 weeks. Our results suggest adequate auto regulatory capacity of the thyroid gland even in those with repeated contrast investigations (up to 40). Routine testing of thyroid function should therefore not be undertaken in this patient group.

Establishing reference intervals for urine and serum iodine levels: A nationwide multicenter study of a euthyroid Chinese population.

CONTEXT: Urinary iodine (UI) is commonly used for evaluating iodine status, whereas serum iodine (SI) is more closely correlated with bioavailable iodine. However, no reliable reference intervals (RIs) for clinical use are available. We aimed to establish RIs for SI, UI, and a ratio of UI to urinary creatinine (U-Cre) applicable to the Chinese population. METHODS: This multicenter cross-sectional study enrolled 930 apparently healthy adults from six representative cities in China (Beijing, Dongying, Guiyang, Urumqi, Shenzhen, and Qiqihar) in 2017. Thyroid ultrasonography and thyroid function tests, including antithyroid antibody tests, were performed to exclude individuals with latent thyroid diseases. An iodine intake-related questionnaire survey was performed. SI and UI were measured using inductively coupled plasma-mass spectrometry. Possible influencing factors of iodine levels were evaluated using multiple regression analysis. RESULTS: Post-exclusion, the final analysis included 894 individuals. Seafood intake frequency was positively correlated with SI (standardized partial regression coefficient = 0.23) but not with UI and UI/U-Cre. SI was positively correlated with serum TT4 (Spearman correlation coefficient: 0.40), TT3 (0.23), and FT4 (0.18). SI and UI showed no age- or sex-specific variations. Significantly higher UI/U-Cre values were observed in Qiqihar than in Beijing, Guizhou, and Shenzhen. Shenzhen showed the lowest UI levels among all evaluated cities. With application of latent abnormal values exclusion procedurere, the RIs for SI, UI, and UI/U-Cre in the population were 36.0-79.3 µg/L, 19-385 µg/L, 22-450 µg/g, respectively. CONCLUSIONS: We established RIs for UI and SI among healthy Chinese individuals with no thyroid nodule or dysfunction.

The Relationship between High Iodine Consumption and Levels of Autoimmune Thyroiditis-Related Biomarkers in a Chinese Population: a Meta-Analysis.

To comprehensively evaluate the relationship between high iodine concentration and biomarker abnormalities related to autoimmune thyroiditis in a Chinese population. Medline, PubMed, and Embase electronic databases were searched for articles published domestically and internationally on the relationship between high iodine concentrations and thyroid hormone antibodies and thyroid-stimulating hormone in China before March 2019. Articles published in Chinese were searched in the China Biology Medicine (CBM) disc, Wanfang Database, and China National Knowledge Infrastructure (CNKI). A total of 16 cross-sectional articles were included in this study, including 9061 participants. A meta-analysis was conducted in Stata 14.0. The binary categorical and continuous variables used odds ratios (ORs) and standardized mean differences (SMDs) with the corresponding 95% confidence intervals (CIs) as the effect statistics, respectively. The results showed that high iodine concentrations had a minimal association with the abnormal rates of thyroid peroxidase antibody (TPOAb) (OR = 1.274, 95% CI (0.957, 1.695), P > 0.05) and thyroglobulin antibody (TGAb) (OR = 1.217, 95% CI (0.911, 1.626), P > 0.05) in the entire population. The thyroid-stimulating hormone (TSH) level in the high iodine group was greater than that in the adaptive iodine group (SMD = 0.202, 95% CI (0.096, 0.309), P < 0.05). The results of the subgroup analysis showed that the abnormal TPOAb rate in pregnant women (OR = 1.519, 95% CI (1.007, 2.291), P < 0.05) and children (OR = 3.365, 95% CI (1.966, 5.672), P < 0.05) in the high iodine group was greater than that in the adaptive iodine group, and the abnormal TGAb rate of children in the high iodine group was greater than that in the adaptive iodine group. The TSH levels of lactating women (SMD = 0.24, 95% CI (0.053, 0.427), P < 0.05), pregnant women (SMD = 0.301, 95% CI (0.176, 0.426), P < 0.05), and children (SMD = 0.25, 95% CI(0.096, 0.309), P < 0.05) in the high iodine group were higher than those in the adaptive iodine group. Egger's and Begg's tests showed no significant (P > 0.1) publication bias. High iodine can increase the risk of abnormal levels of TPOAb, TGAb, and TSH related to autoimmune thyroiditis in pregnant women, lactating women, and children in China.

Direct analysis of bromine and iodine in dried serum spots by laser ablation inductively coupled plasma mass spectrometry.

RATIONALE: Accurate quantitative analysis of bromine and iodine in serum is an important aspect of monitoring body condition, but the volatile loss of halogen in sample pretreatment is a troublesome problem. We present a validated and flexible high-throughput method for quantification of bromine and iodine in dried serum spots (DSS) using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and an external aqueous standard calibration curve. The influence of serum matrix and laser ablation (LA) conditions on the analysis of bromine and iodine in DSS was researched systematically. METHODS: Aqueous standards without matrix matching were used for calibration to analyze bromine and iodine in serum by LA-ICP-MS. 5-µL volumes of the aqueous standard solution and serum samples in 10 times diluted concentration were deposited on the PTFE paper to form dried standard calibration spots (DSCS) and DSS, of less than 2 mm in diameter. LA was performed using a focused Nd:YAG laser beam in raster lineal scan mode. RESULTS: The limits of detection (LODs) for bromine and iodine in DSS were 0.23 and 0.03 mg L-1 , respectively. The relative standard deviation (RSD) for this method was less than 10%. The samples were also detected with matrix matching calibration by ICP-MS. The accuracy of the method was verified by statistical analysis of these results from ICP-MS and LA-ICP-MS. The accuracy is satisfactory with recoveries ranging from 81.5% to 118%. CONCLUSIONS: A novel and simple approach for high-throughput screening of bromine and iodine in DSS has been established by LA-ICP-MS. Calibration could be achieved using an aqueous standard solution instead of a matrix-matching solution. The method allowed analysis of low-volume biological samples without derivatization and decreased the risk of contamination or loss.

Iron and Iodine Status in Pregnant Women from A Developing Country and Its Relation to Pregnancy Outcomes.

Birth related complications and comorbidities are highly associated with a poor nutritional status of pregnant women, whereas iron and iodine are among especially important trace elements for healthy maternal and fetal outcomes. The study compares the status of iron, iodine, and related functional parameters in pregnant and non-pregnant women from a developing country and associates the data with pregnancy complications. The concentrations of ferritin, hemoglobin (Hb), total triiodothyronine (TT3), total thyroxine (TT4), and thyroid-stimulating hormone (TSH) were determined in the blood serum of 80 pregnant women at the time of delivery and compared with 40 non-pregnant healthy controls. Spot urine samples were taken to evaluate the urinary iodine concentration (UIC). In pregnant women, ferritin, Hb concentrations, and UIC were significantly lower, and TT4 values were significantly higher compared to controls. Higher Hb levels were tendentially associated with a reduced risk for pregnancy complications (OR = 0.747, CI (95%) 0.556-1.004; p = 0.053). Regarding covariates, only previous miscarriages were marginally associated with pregnancy complications. High consumption of dairy products was associated with lower Hb and ferritin values. Our results suggest that pregnant women from a developing country have lower iron status with Hb levels being possibly associated with pregnancy complications.

Predicting potential to benefit from an iron intervention: a randomized controlled trial of double-fortified salt in female Indian tea pluckers.

OBJECTIVE: The present study examines characteristics of those who benefited from a dietary Fe intervention comprised of salt double-fortified with iodine and Fe (DFS). DESIGN: Data from a randomized controlled trial were analysed to identify predictors of improved Fe status and resolution of Fe deficiency (serum ferritin (sFt) < 12 µg/l) and low body Fe (body Fe (BI) < 0·0 mg/kg) using non-parametric estimations and binomial regression models. SETTING: A tea estate in West Bengal, India. PARTICIPANTS: Female tea pluckers, aged 18-55 years. RESULTS: Consuming DFS significantly (P = 0·01) predicted resolution of Fe deficiency (relative risk (RR) = 2·31) and of low BI (RR = 2·78) compared with consuming iodized salt. Baseline sFt (ß = -0·32 (se 0·03), P < 0·001) and treatment group (ß = 0·13 (se 0·03), P < 0·001) significantly predicted change in sFt. The interaction of baseline BI with treatment group (ß = -0·11 (se 0·06), P = 0·08) predicted the change in BI. DFS did not significantly predict change in Hb and marginally predicted resolution of anaemia (Hb < 120 g/l). CONCLUSIONS: Baseline Fe status, as assessed by sFt and BI, and consumption of DFS predict change in Fe status and resolution of Fe deficiency and low BI. Anaemia prevalence and Hb level, although simple and inexpensive to measure, may not be adequate to predict resolution of Fe deficiency in response to an intervention of DFS in similar populations with high prevalence of Fe deficiency and multiple nutritional causes of anaemia. These findings will guide appropriate targeting of future interventions.

Excessive iodine intake is associated with formation of thyroid nodules in pregnant Chinese women.

In recent decades, the prevalence of thyroid nodules (TNs) has steadily increased in pregnant women. Therefore, this study aimed to investigate associations between TNs and iodine intake in pregnant women. From March 2016 to May 2017, serum and spot urine samples, as well as demographic data and medical history, were collected from 2353 pregnant women. Urine iodine concentration (UIC) and creatinine (Cr) level were determined in spot urine samples; serum thyroid hormones and thyroid autoantibodies were also determined. We examined the hypothesis that excess iodine intake influences incidence of TNs. Herein, TNs were diagnosed by ultrasonography, whereas demographic data and medical history were collected by questionnaire. Multivariate logistic regression models were used to calculate the odds ratios and their corresponding confidence intervals for TN risk factors. Generalized linear mixed model was used to assess the random effects of the regions. The UIC and UIC to creatinine ratio (I/Cr ratio) were significantly higher in pregnant women with TNs (168 and 190 µg/L, respectively, for UIC [P < .01]; 139 and 155 µg/g, respectively, for I/Cr ratio [P < .01]). Thyroglobulin, age, pre-pregnancy body mass index, and iodine-excessive region were associated with TNs (odds ratio = 1.01, 1.06, 1.04, and 2.38, respectively). Whereas I/Cr ratio was not a significant risk factor for TNs in pregnant women when adjusted for potential confounders, iodine excess (I/Cr ratio >500 µg/g) was a risk factor in pregnant women in their second trimester. People living in areas with excessive iodine in drinking water should decrease their iodine intake, and a safe water source should be provided to ensure that the I/Cr ratio of pregnant women can be maintained at an optimal level.

Thyroid Function Reference Values in Healthy Iodine-Sufficient Pregnant Women and Influence of Thyroid Nodules on Thyrotropin and Free Thyroxine Values.

BACKGROUND: Thyroid function assessment in pregnancy requires specific reference intervals stratified by gestational age and according to each laboratory method. Thyroid nodules may influence thyroid function in pregnant women. The aims of this study were to define the reference values of thyrotropin (TSH) and free thyroxine (fT4) in the three pregnancy trimesters in iodine-sufficient pregnant women, and to analyze the influence of thyroid nodules on thyroid function during pregnancy. METHODS: This was a prospective, longitudinal study comprising 400 pregnant women with no history of thyroid disease and no medication influencing thyroid function. TSH, fT4, antithyroglobulin, and antithyroid peroxidase antibodies were measured each trimester by chemiluminescent immunoassays. Urinary iodine concentration was measured in the first trimester when a thyroid echography was also performed. Women with multiple gestation pregnancies, positive thyroid autoimmunity, TSH values >5 or <0.1 mIU/L with a simultaneous fT4 level above the general population reference value in the first trimester, or clinically significant thyroid nodules (nodules ≥1 cm and/or multiple nodules) were excluded to establish TSH and fT4 reference values. RESULTS: Reference intervals in the first, second, and third trimesters were 0.13-4.16, 0.31-3.73, and 0.58-4.36 mIU/L, respectively, for TSH, and 0.85-1.24, 0.82-1.20, and 0.67-1.06 ng/dL, respectively, for fT4. The total prevalence of thyroid nodules was 28.8% [95% confidence interval (CI) 24.4-33.5%], and 6.0% of the participants showed clinically significant nodules. Pregnant women with thyroid nodules (n = 115) showed consistently lower TSH values during all pregnancy stages (first trimester: median 1.14 mIU/L [interquartile range (IQR) 0.53-1.75 mIU/L] vs. 1.48 mIU/L [IQR 0.94-2.19 mIU/L], p < 0.001; second trimester: 1.22 mIU/L [IQR 0.66-1.77 mIU/L] vs. 1.45 mIU/L [1.04-2.05 mIU/L], p = 0.001; third trimester: 1.74 mIU/L [IQR 1.08-2.36 mIU/L] vs. 1.93 mIU/L [IQR 1.37-2.58 mIU/L], p = 0.041) and higher fT4 values in the first trimester (M ± SD = 1.08 ± 0.14 ng/dL vs. 1.03 ± 0.12, p < 0.001) compared to those without nodules (n = 285). Both pregnant women with clinically significant thyroid nodules and those with nonsignificant ones had lower TSH values than women without nodules. CONCLUSIONS: TSH/fT4 reference intervals in pregnant women from the authors' geographical area will thyroid dysfunction in pregnancy to be appropriately diagnosed. The prevalence of thyroid nodules is high in iodine-sufficient pregnant women, and is associated with low TSH values across pregnancy.

Assessment of iodine supplementation program on thyroid function in Sudan.

The aim of this Study is to investigate whether the Iodine Supplementation Programme is successful or not. This Programme was implemented in Nyala to treat the Iodine deficiency. In this Study Nyala was selected to act as (a study area), due to the history of Iodine deficiency of this region, while Khartoum was selected to act as (a control area). 2000 samples were collected from Khartoum versus 450 samples from Nyala. Thyroxine (T4) and triiodothyronine (T3) levels in two regions were measured and performed by using radioimmunoassay (RIA), also the immunoradiometric assay (IRMA) used for measurement of thyroid stimulating hormone (TSH). The obtained results analyzed by using Statistical Package for Social Sciences (SPSS). (Coherent retrospective) used to determine differences between the study groups. The results of this study showed, there was no significant difference between the mean serum concentrations of T3 and TSH for Khartoum and Nyala. T4of Khartoum (117.93 ±â€¯42.797) nmol/L and the mean serum T4 of Nyala (114.54 ±â€¯45.526) nmol/L, the (P-value = 0.133).T3for Khartoum (1.8040 ±â€¯0.99047) nmol/L and T3of Nyala (1.7307 ±â€¯0.96508) nmol/L, the (P-value = 0.153). TSH for Khartoum (1.4480 ±â€¯0.95807)mIU/Land the mean serum TSH of Nyala (1.4553 ±â€¯1.0244) mIU/L, the (P-value = 0.885). The study showed a clear observation of improvement of hypothyroidism cases in Nyala while the ratio decreased from 64.09% to 0.6%. All the results were carried out according to normal range of Sudanese. The conclusion from this study the iodine supplementation programme is successful. The study recommends rising the health awareness among people by explain the severity of iodine deficiency, and continue in iodine supplementation programme, also establishment of monitoring system including monitoring the presence of iodized diets (sugar, salt, oils, and bread) in the markets. Finally, further studies are needed in other parts of Sudan to assess the size of iodine deficiency problem.

Severely low serum magnesium is associated with increased risks of positive anti-thyroglobulin antibody and hypothyroidism: A cross-sectional study.

Trace elements, such as iodine and selenium, are closely related to autoimmune thyroiditis and thyroid function. Low serum magnesium is associated with several chronic diseases; however, its associations with autoimmune thyroiditis and thyroid function are unclear. We investigated the relationships between low serum magnesium, autoimmune thyroiditis, and thyroid function in 1,257 Chinese participants. Demographic data were collected via questionnaires, and levels of serum thyroid stimulating hormone, anti-thyroid peroxidase antibody, anti-thyroglobulin antibody (TGAb), free thyroxine, serum magnesium, serum iodine, and urinary iodine concentration were measured. Participants were divided into serum magnesium level quartiles (≤0.55, 0.551-0.85, 0.851-1.15, and >1.15 mmol/L). The median serum magnesium level was 0.89 (0.73-1.06) mmol/L; levels ≤0.55 mmol/L were considered severely low (5.9% of participants). The risks of TGAb positivity and Hashimoto thyroiditis (HT) diagnosed using ultrasonography in the lowest quartile group were higher than those in the adequate magnesium group (0.851-1.15 mmol/L) (p < 0.01, odds ratios [ORs] = 2.748-3.236). The risks of total and subclinical-only hypothyroidism in the lowest quartile group were higher than those in the adequate magnesium group (0.851-1.15 mmol/L) (p < 0.01, ORs = 4.482-4.971). Severely low serum magnesium levels are associated with an increased rate of TGAb positivity, HT, and hypothyroidism.

IMPORTANCE OF ISOLATED GESTATIONAL HYPOTHYROXINEMIA IN THE DEVELOPMENT OF OBSTETRIC AND SOMATIC PATHOLOGIES.

The isolated hypothyroxinemia of pregnancy (IHP) has gained specific attention in the specialized literature during the recent years as the possible factor impeding the intellectual development of fetus and increasing the risk of complications related with pregnancy, delivery and perinatal period. Aim of the study was to define the importance of isolated hypothyroxinemia in the development of obstetric and somatic pathologies in outpatient population of pregnant females. The study of prospective design was performed at the base of "David Gagua Clinic" Ltd. Based on hospital referral we selected the pregnant patients who were diagnosed for isolated hypothyroxinemia in the 1st trimester of pregnancy by clinical-laboratory studies. 104 pregnant females with isolated hypothyroxinemia were included in the main group, and 58 pregrant females of reproductive age who were not identified to have thyroid pathology by screening studies were included in the control group,. The questionnaire used in the study process included the retrospective medical history data, demographic findings, information about premorbid background, genetic burden of somatic pathology, social-economical factors (including education level, living conditions, economic income, family environment etc.) and concomitant somatic pathology. In addition, it included the clinical and para-clinical study data and pregnancy follow-up findings. The test studies for thyroid status were performed every trimester and after one month postpartum. The software packages Microsoft Excel (2010) and SPSS/v.12 was used for statistical treatment of data. The digital data is presented by M±STD, where M is the arithmetic mean and STD is the standard deviation of arithmetic mean. To define the confidence interval for the indices and their relation, we calculated 2 and p, whose critical value was defined to be 0.05. Based on analysis of the acquired data, we found out that pregnant females with isolated hypothyroxinemia were more statistically demonstrating asthenia, dry skin, increased hair loss and fragile nails, and from somatic disorders - pregnancy-associated vomiting and anemia. From concomitant diseases, allergic disorders (18.2%), primary dysmenorrhea (27.8%), spontaneous abortions (25%) were taking the highest incidence rate and other obstetric complications (premature delivery, late delivery) were higher in the main group, though statistically significant difference was not demonstrated. It must be noted that isolated hypothyroxinemia in the studied cohort was mostly found in 1st trimester of pregnancy, whereas according to the literature data, the latter is demonstrated more frequently in the second or third trimester. The above mentioned makes us consider that the iodine deficit in the cohort of pregnant females studied by us was probably present before pregnancy as well and maybe with even higher extent. Thus, the isolated hypothyroxinemia developed in the very first trimester of pregnancy still has its negative impact on the pregnancy course and outcome, despite of applied treatment. According to performed studies and their results, for the prevention of obstetric and perinatal complications, its important to administer iodine preparations together with folic acid at pregravid stage in addition to complete elimination of diet abnormalities, plan the pregnancy in stable normothyroxinemia conditions and at positive energetic balance. In addition, its desirable to perform the repeated thyroid status evaluation in the first trimester of pregnancy and timely administration of adequate therapeutic measures in case of finding any pathology.

The impact of surgery on quality of life, esophageal motility, and tracheal anatomy and airflow in patients with benign nodular goiter.

Surgery - is it any good for goiter? In patients with goiter the benefits of thyroid surgery have previously rarely been investigated, as only few alternatives existed. However, the increasing evidence of the advantages with non-surgical substitutes with lower costs and preferable risk profiles prompted us to investi-gate the evidence base for thyroid surgery thoroughly. This thesis consists of three published studies investigating the impact of thyroidectomy on: 1) changes in disease-specific quality of life, 2) swallowing symptoms and esophageal motility, and 3) tracheal anatomy and airflow, in a cohort of patients with benign nodular goiter.