Median Urinary Iodine Research Articles

Influencing Factors and New Reference Intervals of Adult Thyroid Volume in Iodine-Sufficient Areas of China.

The diagnosis of goiter is based on the thyroid volume measured by ultrasound in which iodine plays an important role. The purpose of this study was to evaluate the factors that affect thyroid volume and update the reference range of thyroid volume to provide a new basis for the diagnosis and treatment of goiter. A study population from mainland China was evaluated in the Thyroid disorders, Iodine status and Diabetes Epidemiological (TIDE) study. Thyroid size was measured by ultrasound, and thyroid volume was calculated. A quantile regression model was used to analyze the influence of related factors on the thyroid volume at each percentile. The median urinary iodine concentration (UIC) was 185.54μg/l. The quantile regression model suggested that body surface area (BSA) and thyroid-stimulating hormone (TSH) were positive and negative factors for thyroid volume, respectively (p < 0.01). Excess iodine reduces the median and lower limits of thyroid volume. In iodine-sufficient areas, smoking is no longer a risk factor. The reference value range of thyroid volume stratified by sex was 3.92-19.06ml for males and 3.1-16.17ml for females. The maximum reference ranges for stratification by sex and BSA were 4.25-20.98ml for men and 3.44-18.31ml for women. The iodine nutrition level of the population in mainland China is sufficient. Iodine has the potential to alter the effect of certain factors on thyroid volume and effect is not regional. The new reference interval of adult thyroid volume based on sex and BSA has been updated, which can be used as a reliable reference for updating the diagnostic criteria of endemic goiter.

Serum thyroglobulin as a biomarker of iodine excess and thyroid disease occurrence in adults

BackgroundThyroglobulin (Tg) is considered a sensitive indicator of iodine deficiency. However, the usefulness of Tg as a biomarker of excess iodine is uncertain. The present study aimed to determine the influence of different iodine intake on serum Tg levels, evaluate the influence of thyroid diseases on the distribution of Tg, and identify the factors that may affect Tg levels. MethodsA cross-sectional survey with a total of 1208 adults was conducted in different water iodine areas in China. Urinary iodine concentration (UIC), water iodine concentration (WIC), serum Tg, thyroid-stimulating hormone (TSH), and thyroid antibodies were measured. The thyroid volumes and nodules were measured by B-scan ultrasound. ResultsBased on the WIC data, subjects were divided into three groups. Based on the median urinary iodine concentration (MUIC) data, the iodine levels were adequate, more than adequate, and excess for the WIC < 10 μg/L group, 10 μg/L ≤ WIC ≤ 100 μg/L g, and WIC > 100 μg/L groups, respectively. The median Tg was significantly higher in the excess iodine group than in the adequate iodine group and the more than adequate iodine group (14.6 μg/L vs.12.7 μg/L, P = 0.042; 14.6 μg/L vs.12.5 μg/L, P = 0.004). Multiple linear regression analysis showed that excess iodine intake, goitre, thyroid nodules, and hypothyroidism were significantly related to higher serum Tg levels. ConclusionSerum Tg level can be a promising biomarker of excessive iodine intake, but other factors, especially the presence of thyroid disease, should be considered when using this parameter.

Adverse Effects on the Thyroid of Chinese Pregnant Women Exposed to Long-Term Iodine Excess: Optimal and Safe Tolerable Upper Intake Levels of Iodine

Ensuring optimal iodine nutrition in pregnant women is a global public health concern. However, there is no direct data on safe tolerable upper intake levels (ULs) for pregnant women. A cross-sectional study was performed to determine the ULs of pregnant women. A total of 744 pregnant women were enrolled in this study. The median (IQR) urinary iodine concentration (UIC) in pregnant women was 150.2 (87.6, 268.0) μg/L, and the urinary iodine excretion (UIE) over 24 h was 204.2 (116.0, 387.0) μg/day. Compared with those with a UIE figure of between 150-250 μg/day, the reference group, the prevalence of thyroid dysfunction was 5.7 times higher (95%CI: 1.7, 19.2) in pregnant women with a UIE figure of between 450-550 μg/day, and 3.9 times higher (95%CI: 1.5, 10.3) in pregnant women with a UIE figure of ≥550 μg/day. Compared with an estimated iodine intake (EII) of between 100-200 μg/day, the reference group, the prevalence of thyroid dysfunction was 4.3 times higher (95%CI: 1.3, 14.4) in pregnant women with a UIE figure of between 500-600 μg/day, and 3.6 times higher (95%CI: 1.5, 8.9) in pregnant women with UIE of ≥600 μg/day. In general, our cross-sectional study found that excessive iodine intake during pregnancy appears to directly increase the risk of thyroid dysfunction. Avoiding chronic iodine intakes of 500 μg/day or higher or having a UIE figure of ≥450 μg/day is recommended for pregnant women in China.

Systematic review and meta-analysis of iodine nutrition in modern vegan and vegetarian diets.

Vegan and vegetarian diets are widely supported and adopted, but individuals following such diets remain at greater risk of iodine deficiency. This systematic review and meta-analysis was conducted to assess the iodine intake and status in adults following a vegan or vegetarian diet in the modern day. A systematic review and quality assessment were conducted from October 2020 to December 2022 according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidance. Studies were identified in Ovid MEDLINE, Web of Science, PubMed, and Scopus. Eleven articles were eligible for review containing 4421 adults (aged ≥ 18 years). Vegan groups had the lowest median urinary iodine concentration (mUIC) (12·2/l). None of the dietary groups had mUIC within the optimal range for iodine status (100-200 µg/l) (WHO). Vegan diets had the poorest iodine intake (17·3 µg/d) and were strongly associated with lower iodine intake (P = < 0·001) compared with omnivorous diets. Lower intake in vegan diets was influenced by sex (P = 0·007), the presence of voluntary or absence of Universal Salt Iodisation (USI) programmes (P = 0·01 & P = < 0·001), and living in a country with adequate iodine nutrition (P = < 0·001). Vegetarians and particularly vegans living in countries with no current USI programme continue to have increased risk of low iodine status, iodine deficiency and inadequate iodine intake. Further research into the usefulness of mandatory fortification of vegan appropriate foods is required.

Estimation of appropriate dietary intake of iodine among lactating women in China based on iodine loss in breast milk.

Data on iodine loss in breast milk, which are critical for establishing the appropriate dietary iodine intake for lactating women, is currently limited. A study was conducted to assess iodine loss in breast milk among Chinese lactating women to estimate the appropriate dietary intake of iodine. A total of 54 pairs of healthy, lactating women and their infants aged 0-6months were recruited from Tianjin and Luoyang cities in China. A 4days infant weighing study was conducted to assess iodine loss in the breast milk of lactating women. Mothers were required to weigh and record their infants' body weights before and after each feeding for a 24h period from 8:00 am to 8:00 am. During the weighing study, 2812 breast milk samples and 216 24-h urine samples were collected from each lactating mother for four consecutive days. In addition, a 3days 24h dietary record, including salt weighing and drinking water samples collecting, was performed by each lactating mother to determine dietary iodine intake during the weighing study. The average dietary iodine intake of lactating women was 323 ± 80μg/d. The median breast milk iodine concentration and 24h urinary iodine concentration of lactating women were 154 (122-181) and 135 (104-172)μg/L, respectively. The mean volume of breast milk and the mean iodine loss in the breast milk of lactating women were 711 ± 157mL/d and 112 ± 47μg/d, respectively. The appropriate dietary intake of iodine among lactating Chinese women is approximately 260µg/d. Based on the iodine loss in breast milk (110μg/d) found in this study, and the estimated average requirement of iodine for adults, the appropriate dietary intake of iodine among lactating Chinese women is 260µg/d, which is higher than the 240μg/d recommended by the China Nutrition Science Congress in 2013.

Excessive iodine status among school‐aged children in the State of Qatar: Results of the National Iodine Deficiency Disorder Survey

AbstractBackgroundIodine deficiency poses a significant public health challenge worldwide, particularly in preschool children and pregnant women. Assessing the iodine intake at a population level is essential, as both deficient and excessive iodine status can have adverse health consequences. The main objective of this survey is to understand the iodine deficiency status in schoolchildren aged 6–12 years in the State of Qatar.MethodsA cross‐sectional survey was conducted from March to June 2014 among school‐aged children using a two‐stage cluster sampling technique. Anthropometric, biochemical, clinical, and dietary parameters for seafood were collected. Spot urine samples were collected from 967 participants, and a repeat random subsample urine was collected from 288 participants. Overall median urinary iodine concentration (UIC) was calculated. Iodine content in household salt samples was estimated by qualitative and quantitative methods. Mann–Whitney U test was used for comparison.ResultsThe median UIC was 333.2 μg/L (IQR = 228.6). UIC prevalence rates between 300–999 and &gt;1000 μg/L were 56.7% and 2.8%, respectively. The goiter prevalence was 0.4%. A significant difference was noted in overall median UIC levels between boys and girls (p = 0.003). Adequate iodized salt consumption was reported by 74.9% of households, and weekly seafood consumption was reported by one third of the respondents.ConclusionThe results indicate an excess intake of iodine among the studied population in the State of Qatar, and national efforts are needed to bring iodine intake and concentration levels within the cutoff value for the concerned survey population's age group. In addition, a surveillance system needs to be set up for continuous monitoring of iodine content and salt intake at the population level in the State of Qatar.

Iodine nutrition with North Atlantic living: the Faroese adolescents.

Iodine nutrition is critical for human health. While iodine excretion was low within the recommended range among adult Faroese, younger generations tend to abandon local foods. Such changes raise a concern about iodine intake, which led us to perform this first study of iodine nutrition among teenagers in the North Atlantic islands. We used samples from a nationwide collection of urine samples in 14-year-olds following iodine fortification of salt in 2000. Urine was analysed for iodine and creatinine to adjust for dilution by iodine/creatinine, and a food frequency questionnaire was used to record the intake of iodine-rich foods. The 129 participants yielded a 90 % precision of the estimated iodine nutrition level. The median urinary iodine concentration (UIC) was 166 μg/l (bootstrapped 95 % confidence interval 156–184 μg/l). The median creatinine-adjusted UIC was 132 μg/g (bootstrapped 95 % CI 120–138 μg/g). Fish and whale meat dinners were more frequent among residents of villages compared with the capital: median fish dinners, 3v.2 per week (P= 0⋅001), and whale meat, 1v.0⋅4 per month (P&lt; 0⋅001). UIC decreased with fewer fish dinners (P= 0⋅03). Our study demonstrated that Faroese teenagers were iodine-replete. The changing dietary habits emphasise the need for continuous monitoring of iodine nutrition and surveying iodine deficiency disorders.

Первичная заболеваемость тиреоидной системы и йодное обеспечение организма взрослого населения Заводского района г. Минска

Currently, iodine deficiency diseases are one of the most common diseases of non-infectious origin. In the Republic of Belarus, preventive measures are being taken to eliminate the problem of iodine deficiency, in particular, a state strategy has been developed and implemented, the main measure of which is the mandatory use of only iodized salt in the food industry and public catering. Despite the measures taken, the problem of iodine deficiency remains relevant, especially for children and pregnant women. According to the results of the assessment of iodine sufficiency in the world, published by the RIAC on Surveillance for Iodine Deficiency Diseases (ICCIDD) - a global non-commercial, spheral need created for the use of iodine deficiency and the consequences of its negative examination on health, adequate iodine intake is provided in the Republic of Belarus. In 2016, the Global Iodine Network published maps characterizing iodine sufficiency for two main assessment categories - school-age children and pregnant women, confirming the status of the Republic of Belarus as a country with adequate iodine sufficiency. However, despite the results achieved, from the standpoint of medical monitoring, the quality of studies conducted to monitor the iodine supply of the population, the risks of excessive salt intake remain relevant. In this paper, a comparative analysis of the dynamics of the primary incidence of thyroid pathology in the population of the Zavodskoy district of the city of Minsk for the period 2016-2020 was carried out. According to the results of the analysis, a positive trend in the primary incidence of simple goiter, nodular non-toxic goiter and thyroiditis was revealed, while the dynamics of the primary incidence of hypothyroidism did not change. According to the data presented, the presence of iodine deficiency with a median urinary iodine excretion of 196.15 gg/l was revealed in pregnant women of the Zavodskoy district of Minsk in 2021. An analysis of the questionnaire survey of the nature of the nutrition of pregnant women showed that most of the surveyed do not know about the benefits of using iodized salt for the development of the fetus, and therefore the reason for the formation of iodine deficiency in the body of pregnant women is the insufficient intake of iodine in the body and refusal to take iodine preparations. In the surveyed region, 22 % of women do not comply with the prescription of endocrinologists about the need to take iodine-containing drugs.

Environmental exposure to perchlorate, nitrate and thiocyanate, and thyroid function in Chinese adults: A community-based cross-sectional study

BackgroundEvidence on environmental exposure to perchlorate, nitrate, and thiocyanate, three thyroidal sodium iodine symporter (NIS) inhibitors, and thyroid function in the Chinese population remains limited. ObjectiveTo investigate the associations of environmental exposure to perchlorate, nitrate, and thiocyanate with markers of thyroid function in Chinese adults. MethodsA total of 2441 non-pregnant adults (mean age 50.4 years and 39.1% male) with a median urinary iodine of 180.1 μg/L from four communities in Shenzhen were included in this cross-sectional study. Urinary perchlorate, nitrate, thiocyanate, and thyroid profiles, including serum free thyroxine (FT4), total thyroxine (TT4), free triiodothyronine (FT3), total triiodothyronine (TT3), and thyroid stimulating hormone (TSH), were measured. Generalized linear model was applied to investigate the single-analyte associations. Weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) models were used to examine the association between the co-occurrence of three anions and thyroid profile. ResultsThe median levels of urinary perchlorate, nitrate, and thiocyanate were 5.8 μg/g, 76.4 mg/g, and 274.1 μg/g, respectively. After adjusting for confounders, higher urinary perchlorate was associated with lower serum FT4, TT4, and TT3, and higher serum FT3 and TSH (all P < 0.05). Comparing extreme tertiles, subjects in the highest nitrate tertile had marginally elevated TT3 (β: 0.02, 95% CI: 0.00–0.04). Each 1-unit increase in log-transformed urinary thiocyanate was associated with a 0.04 (95% CI: 0.02–0.06) pmol/L decrease in serum FT3. The WQS indices were inversely associated with serum FT4, TT4, and FT3 (all P < 0.05). In the BKMR model, the mixture of three anions was inversely associated with serum FT4, TT4, and FT3. ConclusionsOur study provides evidence that individual and combined environmental exposure to perchlorate, nitrate, and thiocyanate are associated with significant changes in thyroid function markers in the Chinese population with adequate iodine intake.

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.

Defisiensi mikronutrien pada anak usia 12-59 bulan di Desa Lebih, Kabupaten Gianyar, Bali

Deficiency of micronutrients in children of age 12-59 months in Lebih Village, Gianyar District, BaliBackground: Lack of food intake, either in quantity or quality, will continuously cause children to get sick easily, such as being susceptible to infectious diseases and ultimately inhibiting the children’s growth.Objective: This study aimed to describe the status of micronutrients (zinc and iodine) and anemia status among children aged 12-59 months in Lebih Village. Methods: This analytic observational study used a cross-sectional design conducted in Lebih Village, Gianyar Regency. The study population was all children under five aged 12-59 months. In addition, 91 children under five were selected as research subjects using the probability proportional to size method. The data collected were the identity of the subjects (children under five and their mothers) using the interview method, serum zinc levels, urinary iodine excretion (EIU) levels, and Hb levels. Results: The results showed that the subjects’ mean age was 37.0±13.3 months, and most subjects (54.9%) were male. The biochemical examination showed that the mean serum zinc levels, the median urine iodine levels, and the mean Hb levels were 72.5±6.3 g/dL, 78.5 g/L, and 12.7±1.8 g/dL, respectively. 17.6% of the subjects had anemia, 14.3% had zinc deficiency, and 60.4% had iodine deficiency. Conclusion: Children under five aged 12-59 months in Lebih Village had micronutrient deficiencies such as zinc, iodine, and iron.

The prevalence of insufficient iodine intake in pregnancy in Africa: a systematic review and meta-analysis

BackgroundFortification of foodstuffs with iodine, mainly through iodization of salt, which commenced in several African countries after 1995 is the main method for mitigating iodine deficiency in Africa. We assessed the degree of iodine nutrition in pregnancy across Africa before and after the implementation of national iodine fortification programs (CRD42018099434).MethodsElectronic databases and gray literature were searched for baseline data before implementation of population-based iodine supplementation and for follow-up data up to September 2020. R-metamedian and metamean packages were used to pool country-specific median urinary iodine concentration (UIC) estimates and derived mean UIC from studies with similar features.ResultsOf 54 African countries, 23 had data on iodine nutrition in pregnancy mostly from subnational samples. Data before 1995 showed that severe iodine deficiency was prevalent in pregnancy with a pooled pregnancy median UIC of 28.6 μg/L (95% CI 7.6–49.5). By 2005, five studies revealed a trend towards improvement in iodine nutrition state in pregnancy with a pooled pregnancy median UIC of 174.1 μg/L (95% CI 90.4–257.7). Between 2005 and 2020 increased numbers of national and subnational studies revealed that few African countries had sufficient, while most had mildly inadequate, and some severely inadequate iodine nutrition in pregnancy. The pooled pregnancy median UIC was 145 μg/L (95% CI 126–172).ConclusionImprovement in iodine nutrition status in pregnancy following the introduction of fortification of foodstuffs with iodine in Africa is sub-optimal, exposing a large proportion of pregnant women to the risk of iodine deficiency and associated disorders.Systematic review registrationPROSPERO CRD42018099434

Association between Elevated Iodine Intake and IQ among School Children in Portugal.

The goal of this work was to examine whether elevated iodine intake was associated with adverse effects on IQ among school-age children in Portugal. In a representative sample of children from the north of the country, IQ percentiles by age (assessed with Raven's Colored Progressive Matrices) were dichotomized to &lt;50 ("below-average" IQs) and ≥50. Morning urine iodine concentrations, corrected for creatinine, were dichotomized to &lt;250 µg/g and ≥250 µg/g, according to the European Commission/Scientific Committee on Food's tolerable upper level of daily iodine intake for young children. Data were examined with Chi-square tests, logistic regression, and GLM univariate analysis. The sample (N = 1965) was classified as generally iodine-adequate (median urinary iodine concentration = 129 µg/L; median iodine-to-creatinine ratio = 126 µg/g) according to the WHO's criteria. A greater proportion of children in the ≥250 µg/g group had below-average IQs, compared to children with less than 250 µg/g (p = 0.037), despite a sizable (though non-significant) proportion of children in the less-than-250 µg/g group also presenting below-average IQs, at the bottom of the iodine distribution (&lt;50 µg/g). The proportion of below-average IQs increased with increasingly elevated iodine concentrations (p = 0.047). The association remained significant after the adjustment for confounders, with the elevated iodine group showing increased odds of having below-average IQs when compared with the non-elevated iodine group (OR 1.55; 95% CI 1.11-2.17; p = 0.011). Consistently, the former group presented a lower mean IQ than the latter (p = 0.006). High iodine intake was associated with lower IQs even in a population classified as iodine-adequate. These results bear on child cognition and on initiatives involving iodine supplementation.

Assessing the trend of iodine deficiency among antenatal patients of the university of Port Harcourt teaching hospital

Background: Iodine deficiency is a global health problem of public health significance; it is the leading cause of preventable neurodevelopmental impairment in children globally. This deficiency can occur in pregnancy leading to various degree of morbidity. Aims and objective: This study was aimed at determining the pattern and severity of iodine deficiency amongst pregnant women in the University of Port Harcourt Teaching Hospital. Methodology: This study was a hospital-based cross-sectional comparative study that measured the urinary iodine concentration in two subgroups of the population; pregnant women and non- pregnant women of reproductive age. Structured questionnaires were administered to and urine samples were obtained from the participants. The urinary iodine concentration was measured using the Sandell-Kolthoff reaction. The data from the structured questionnaire was entered into a spreadsheet and analyzed using the statistical package for social sciences 25.0 software package (IBM, Armonk, NY, USA). Results: The mean age for the pregnant study group was 32.15±5.2, the median and modal age was 31 years, with a range of 23 to 43 years. Mild iodine deficiency was seen in 57.1% of the non-pregnant respondents and 34.4% of the pregnant respondents. Moderate iodine deficiency was seen in 42.9% of non-pregnant respondents and 56.2% of pregnant respondents. Severe Iodine deficiency was observed only among the pregnant respondents (9.4%) The median urinary iodine concentration (Median UIC) among pregnant women was 42.87ug/l, while the median UIC among non-pregnant women was 52.33ug/l. A Mann-Whitney U test indicated that this difference was statistically significant, U (NPregnant=66, Nnon-pregnant =63) =1234.5, z= -3.98, p≤ 0.001). Conclusion: This study found that iodine deficiency was prevalent among women in the study population (pregnant and non-pregnant women), however, it was more severe in pregnant women. Based on the results of our study there is an urgent need for iodine supplementation in our pregnant women.

The advancement of Ethiopia's salt iodization programme-The success story of the central iodized facilities.

The objective of this article is to characterize the value of centralized iodization facilities (CIFs) to advance Ethiopia's salt iodization programme and its impact on the population iodine status. The analysis is based on a review of publications relating to salt iodization and iodine deficiency control efforts in Ethiopia. The country has made remarkable progress in improving iodized salt coverage, leading to improved iodine intake across its population that would otherwise be at high risk of iodine deficiency disorders. Establishment of central processing facilities, more frequent monitoring and generation of data and encouraging private sector investment have been instrumental in this achievement. Ethiopia has thus achieved and sustained greater than 89% HH iodized salt coverage from its lowest point of 15% coverage and subsequently improved iodine intake across its population. Iodine intake sufficiency in a population is assessed by median urinary iodine concentration (MUIC). The lessons learned and the experience with CIFs have applicability in several other countries where fragmented salt production continues to create barriers to achieve higher iodized salt coverage.

Time Series and Spatial Epidemiological Analysis of the Prevalence of Iodine Deficiency Disorders in China

ObjectiveTo recognize the spatial and temporal characteristics of iodine deficiency disorders (IDD), China national IDD surveillance data for the years of 1995–2018 were analyzed. MethodsTime series analysis was used to describe and predict the IDD related indicators, and spatial analysis was used to analyze the spatial distribution of salt iodine levels. ResultsIn China, the median urinary iodine concentration increased in 1995–1997, then decreased to adequate levels, and are expected to remain appropriate in 2019–2022. The goiter rate continually decreased and is expected to be maintained at a low level. Since 2002, the coverage rates of iodized salt and the consumption rates of qualified iodized salt (the percentage of qualified iodized salt in all tested salt) increased and began to decline in 2012; they are expected to continue to decrease. Spatial epidemiological analysis indicated a positive spatial correlation in 2016–2018 and revealed feature regarding the spatial distribution of salt related indicators in coastal areas and areas near iodine-excess areas. ConclusionsIodine nutrition in China showed gradual improvements. However, a recent decline has been observed in some areas following changes in the iodized salt supply in China. In the future, more regulations regarding salt management should be issued to strengthen IDD control and prevention measures, and avoid the recurrence of IDD.

Factors associated with inadequate urinary iodine concentration among pregnant women in Mbeya region Tanzania.

Background: Insufficient and excessive iodine intake during pregnancy can lead to serious health problems. In Tanzania, information available on iodine status during pregnancy is minimal. The aim of this study was to assess the iodine status and its association with socio-demographic factors in pregnant women in the Mbeya region, Tanzania. Method: A cross sectional survey involving 420 pregnant women (n=420) registered in Reproductive and Child Health Clinics was conducted. Data were collected via interviews and laboratory analysis of urinary iodine concentration (UIC). Results: Median UIC was 279.4μg/L (+/-26.1) to 1915μg/L. Insufficient iodine intake (UIC below 150μg/L) was observed in 17.14% of participants, sufficient intake in 24.29% and 58.57% had intakes above the recommended level (&gt;250μg/L). Pregnant women who consume fish had an increased risk of insufficient iodine [Adjusted OR7= 2.60 (95%CI 1.31-5.15)] while the risk was lower for those who attended primary education compared to non-formal education [Adjusted OR= 0.29 (95%CI 0.08-0.99)]. Pregnant women resident in Mbarali district aged between 35-49 years were associated with an increased risk of UIC above recommended level [Adjusted OR=4.09 (95%CI 1.85-9.010] and [Adjusted OR=2.51 (95%CI 0.99-6.330] respectively . Conclusion: This study demonstrated a significant relationship between geographical factors (residence in the Mbarali district) and excess median urine iodine concentration, in addition, this study also found an association between consumption of freshwater fish and insufficient mean urine iodine concentration as indicated by the World Health Organization recommendation. Therefore, educational programs on iodine intake are needed as attending primary education was found to be a protective factor for insufficient median urine iodine concentration.

Neonatal thyrotropin - indicatior of monitoring of iodine deficiency severity. What's level is considered a «cutoff point»?

The issues of monitoring the effectiveness of iodine deficiency prevention programs are an important component in the process of iodine elimination. Neonatal thyrotropin (TSH) has been used as a criterion for the severity of iodine deficiency since 1994, however, the question of the "cut-off point" of the neonatal TSH level has been widely discussed in the recent literature. Evaluate the criterion for neonatal hyperthyroidism above 5 mIU/l from the perspective of monitoring iodine deficiency and establish a «cut-off point» on the model of healthy pregnant women with adequate iodine status. A prospective study was conducted in a population of pregnant women in the city of Tyumen, with the formation of observation groups according to the level of iodine excretion in the urine - the main group (with adequate iodine status throughout the entire gestation period) and the comparison group (women with iodine levels less than 150 μg/l). The results of neonatal screening for congenital hypothyroidism in children of women participating in the study were evaluated. The frequency of neonatal TSH above 5mIU/l was assessed in the observation groups. ROC-analysis was performed and a «cut-off point» of the level of neonatal TSH was established as an indicator of iodine deficiency. The median urinary iodine concentration in the population of pregnant women in Tyumen was 159.05 μg/l, the incidence of goiter was 0.38%, the incidence of neonatal hyperthyroidism above 5 mIU/l was 2.88%, which characterizes adequate iodine intake in the pregnant population women. The frequency of neonatal TSH above 5 mIU/l in newborns from women from the main group was 1.47%, and in the comparison group - 9.3% (p = 0.076). ROC analysis revealed a threshold value of neonatal TSH of 2.77 mIU/l at the cut-off point, which corresponded to the highest value of the Youden index. Urinary iodine concentrations greater than 150 μg/l were predicted for nTSH values below this value. Analysis of databases of neonatal screening for congenital hypothyroidism makes it possible to effectively, quickly and at minimal cost annually assess the iodine status in the population. The established «cut-off point» of neonatal TSH in the model of healthy pregnant women with adequate iodine intake in our work is 2.77 mIU/l, the absence of statistically significant differences in the incidence of neonatal hyperthyroidism above 5 mIU/l from women with different iodine status during pregnancy indicate the need to revise the existing threshold of 5 mIU/l and may be an incentive to conduct large-scale studies in regions with different iodine supply.

The relationship between different iodine sources and nutrition in pregnant women and adults.

BackgroundDifferent iodine supplement measures emerge along with the economy development in China. The article objectives are to compare and explore the relationship between iodine sources and nutrition of pregnant women and adults.MethodsA total of 2,145 pregnant women and 1,660 adults were investigated by multi-stage random method. Questionnaire was used to collect basic information and the consumption of food, water, and iodine preparations. Household salt and individual urine and blood samples were collected, and thyroid function and morphology of pregnant women were measured.ResultsThe median urinary iodine concentration (MUIC) of pregnant women (164.49 μg/L) was lower than adults (187.30 μg/L, p < 0.05). Iodine supplement with IS (iodized salt) was the main measure for pregnant women and adults, and the difference was mainly on the consumption of iodine preparations between pregnant women (5.19%) and adults (0.85%). Moreover, adults’ dietary iodine intake from food (100.6 μg/day), IS (140.8 μg/day), and drinking water (6.0 μg/day) was higher than those of pregnant women (86.5, 107.2, and 3.5 μg/day, respectively). Compared with iodine supplement with IS, ISFP (IS + iodine-rich food + iodine preparations) could reduce the risk of iodine deficiency for pregnant women. The MUICs for pregnant women and adults of iodine supplements with IF (iodine-rich food) and ISF (IS + iodine-rich food) were lower. For pregnant women, thyroid nodule (11.90%) and peroxidase antibody (TPOAb) positive (9.32%) were high prevalent thyroid diseases, and habitation (urban/rural), gestation, annual income, and drinking water type would affect them.ConclusionPregnant women and adults had adequate iodine nutrition in four provinces. Their iodine supplement measures were different, the consumption of iodine preparations in pregnant women was higher, and their dietary iodine intake was lower than adults. ISFP was an effect measure for pregnant women to supplement iodine.

Iodine status in Danish pregnant women after an increase in iodine fortification.

Iodine fortification programmes are implemented in many countries and often associated with an increase in population iodine intake. However, the initial attempt may not be sufficient and in Denmark the level of iodine added to salt was increased in 2019. Sparse evidence is available on the impact of such modification in iodine fortification. The aim of this study was to evaluate iodine status in Danish pregnant women in 2021 after this increase in iodine fortification and compare to iodine status in 2012. Cross-sectional study. Pregnant women in the North Denmark Region referred for routine obstetric ultrasound in 2021. Participants filled out a questionnaire and delivered a spot urine. Median urinary iodine concentration (UIC) was calculated and assessed according to the recommended range in pregnancy (150-249 µg/L). Altogether 147 pregnant women were included and 88% used iodine-containing supplements. Median UIC was overall 77 µg/L [95% confidence interval (CI): 61-96 µg/L], which was lower than in 2012 (101 µg/L [95% CI: 89-111 µg/L]) (p < 0.001). Considering sources of iodine intake in pregnancy, lower daily intake of dairy products (p = 0.008) and bread (p < 0.001) and a lower content of iodine in the supplement used (p < 0.001) was seen in 2021 compared to 2012. Despite an increase in iodine fortification and frequent use of iodine-containing supplements, iodine status in pregnant women in the North Denmark Region was insufficient. Results call for continued monitoring and attention to ensure adequate iodine status during pregnancy in Denmark.