Median Urinary Iodine Concentration Research Articles

English

BACKGROUND The importance of adequate iodine status in pregnancy is undoubted as its deficiency is associated with adverse pregnancy outcomes for the mother as well as the foetus and neonate. Although median urine iodine concentration can assess iodine status of the population but not at an individual level. The purpose of this study was to assess the nutritional status of iodine and identify its effects on thyroid function during the first trimester of pregnancy. METHODS The study was carried out on 341 euthyroid healthy pregnant women using urine iodine concentration and other parameters of thyroid panel at a tertiary care hospital. RESULTS Median (interquartile range) urine iodine concentration and thyroid stimulating hormone (TSH) were 227.37 (161.7, 343.86) μg / L and 1.8 (1.1, 2.7) mIU / L respectively and Mean ± SD of free thyroxine and thyroid peroxidase antibodies were 14.53 ± 2.02 pmol / L and 38.23 ± 9.29 kIU / L respectively. Only thyroid peroxidase antibodies showed significant difference across groups with different iodine status. A positive correlation of urine iodine concentration (UIC) with thyroid peroxidase antibodies was observed (r = 0.137, P = 0.011). Multiple regression analysis revealed that thyroid peroxidase antibodies can serve as an independent predictor of iodine status in the presence of normal levels of TSH and FT4 (t - 3.063, CI; 0.880, 4.038, P = 0.002). CONCLUSIONS Thyroid peroxidase antibodies progressed positively with increase in urine iodine concentration indicating its role as a marker of iodine nutritional status and for early identification of women who can develop autoimmune thyroiditis resulting in hypothyroidism even prior to elevation of thyroid stimulating hormone levels. KEY WORDS Anti-TPO Ab, Free Thyroxine, Thyroid Stimulating Hormone, Urine Iodine Concentration

Factors influencing the iodine status of children aged 12 to 59 months from Jaffna District, Sri Lanka in the post-iodization era; a descriptive, cross-sectional study.

BackgroundIodine status, including Iodine Deficiency (ID) of the children aged 12–59 months of Jaffna District, Sri Lanka, have never been studied. This study thus aimed to assess ID among children aged 12–59 months by monitoring the Urinary Iodine Concentrations (UIC), the prevalence of goitre, and the factors causing ID.MethodA cross-sectional study was conducted among 846 children aged 12–59 months in Jaffna District, Sri Lanka. Sociodemographic characteristics and other factors were collected using an interviewer-administered questionnaire. Dietary pattern of children was obtained using semi-quantitative food frequency questionnaire. We performed urinary iodine estimation and physical examinations to detect the goitre, according to the World Health Organization criteria. A multivariate logistic linear regression model was used to identify the factors that causing ID.ResultThe median UIC was 146.4 μg/L (interquartile range = 112.6–185.3 μg/L). Based on the UIC (<100 μg/L), 17.8% had ID, of which 15.7% and 2.1% had mild and moderate ID. The mean consumption of iodine from food was 128.7 (±20.2) μg/day. Gender variation had no influence on ID (p>0.05). Median UIC was significantly associated with living area, wealth status, type of drinking water, and method of iodized salt usage. A higher percentage of ID was significantly associated with younger age [AOR 2.32 (95% CI: 1.31–4.10)], urban area [AOR 1.94 (95% CI 1.27–2.96)], inland regions [AOR 3.20 (95% CI 1.85–5.55)], improper method of iodized salt usage [AOR 3.63 (95% CI: 1.38–9.56)], and low consumption of iodine-containing foods. The neck palpation revealed that only three children had goitre (0.4%).ConclusionThis study revealed that high ID among the children in Jaffna children was due to improper usage of iodized salt, even though the iodized salt is freely available in the region, living area, and age, while the prevalence of goitre was not significantly identified as a public health problem.

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

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

Urinary iodine and sodium concentration and thyroid status in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

ObjectivesTo evaluate urinary iodine concentration (UIC) in civil servants aged 35-74 years of the Brazilian Study of Adults Health (ELSA-Brasil) to analyze its relationship with sociodemographic, clinical risk factors, lifestyle, urinary Na and thyroid status. DesignCross-sectional study in six Brazilian cities. MethodsThis analysis included 792 participants with information about urinary iodine concentration (UIC). Thyroid status was defined by serum levels of TSH/FT4 and the current use of antithyroid drugs for treatment of overt hyperthyroidism or levothyroxine to treat overt hypothyroidism. The determination of UIC was carried out with an inductively coupled plasma mass spectrometer (ICP-MS) and was expressed as median with Interquartile Range (IQR). ResultsIn 792 participants, thereof 52% women, mean age was 51.9 (9.0) years. The median UIC was 219 (IQR, 166-291) for all persons studied, thereof 211 (IQR, 157-276) for women and 231 (IQR, 178-304) for men. According to the WHO classification, for all persons studied, 60% had more than adequate iodine-supply (UIC ≥200 μg/L), 37% were adequately supplied (UIC 100-199 μg/L) and <3% had a deficient iodine status (<100 μg/L). In the 35-44-year age strata, which includes women of childbearing age, 23.2% of women presented less than 150 μg/L of UIC. No differences in UIC were detected according to thyroid status. (P = 0.39) The correlation between Ur-Na and UIC showed a Spearman coefficient of 0.52 (P < 0.0001) and it was also found an association of Ur-Na with UIC: Beta of 1.76 (95% Confidence Interval (95% CI): 1.01 to 2.51. The urinary Na concentration showed a synergy with the UIC, that means medians of 57, 72, 107 and 141 mmol Na/L urine (P < 0.001) in the groups with the four UIC classes according to the WHO grading mentioned above. The very low Na content in the persons exhibiting <100 μg/L UIC seems to reflect also a higher urine volume due to the frequent use of diuretics. The strong relationship between the urinary Na concentration and the UIC points to a dependence of the UIC on the individual consumption of iodized salt, which should be more considered in future studies. The strong relationship between the urinary Na concentration and the UIC points to a dependence of the UIC on the individual consumption of iodized salt, which should be more considered in future studies. ConclusionsEuthyroid persons were dominating by more than four fifths and no significant association was found between UIC and thyroid status. Although most of the persons studied present more than adequate iodine intake it was observed that nearly a quarter of women in childbearing age are iodine deficient.

Iodine nutrition among the adult population of the Faroe Islands: a population-based study.

The WHO recommends monitoring iodine status in all populations with median urinary iodine concentration (UIC) below 100 µg/l suggesting iodine deficiency. There are no data on the iodine intake among the population of the Faroe Islands. This study aimed to provide data on iodine nutrition in a representative sample of the general adult population from the Faroe Islands. We conducted a population-based cross-sectional survey in 2011-2012 and measured iodine in urine from 491 participants (294/197 men/women) using the ceri/arsen method after alkaline ashing. Participants include about 100 subjects in each of four adult decades and included participants from both the capital city and villages. The median UIC was low within the recommended range 101 µg/l (range 21-1870 µg/l). No samples were in the range suggesting severe iodine deficiency, but half of the samples were in the range of just adequate or mildly insufficient iodine intake with UIC markedly lower in women than in men (86 v. 115 µg/l; P < 0·001). Intake of fish and whale meals affected the UIC. In conclusion, nearly half of the population had an iodine excretion in the range of borderline or mild iodine deficiency. The lowest iodine nutrition level among Faroese women is a concern as it may extend to pregnancy with increased demands on iodine nutrition. In addition, we found that large variations and the intermittently excessive iodine intakes warrant follow-up on thyroid function in the population of the Faroe Islands.

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

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. This cross-sectional study was part of an observational longitudinal cohort Mother and Infant Nutrition Investigation; data obtained at six months postpartum are reported. Mother-infant pairs (n=87) were recruited at three months postpartum and followed up at six months postpartum (n=78). 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). 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). 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.

Assessment of the Impact of Salt Iodisation Programmes on Urinary Iodine Concentrations and Goitre Rates: A Systematic Review

Introduction Two main strategies are currently recommended for the prevention and control of iodine deficiency in the world: implementation of universal salt iodisation programmes and permanent monitoring of iodine consumption by the population. Although iodine intake and coverage iodised salt have increased in the world population, iodine deficiency disorders (IDDs) may still be a public health problem in a few countries or communities. Objective To assess the impact of salt iodisation programmes on urinary iodine concentrations and goitre rates in the world population. Methodology. A systematic review based on the PRISMA method. We obtained articles from Scopus, Science Direct, MEDLINE databases, and other sources between March and April 2020, without limitation of dates. “Iodisation” AND “urinary iodine concentrations” AND “goitre” in English, Portuguese, and Spanish without filters and clinical trial, case-control, and cross-sectional studies were included in this review. Results Of 479 abstracts, twenty-three were eligible. Coverage on iodised salt was in the range of 16 to 98%, and 11 studies had been sufficient, whilst eight studies had adequate iodine concentration in salt and three excess. 81.8% of studies that had an adequate median of UIC had a good impact in their respective salt iodisation programmes. Conclusion After 18 years of salt iodisation programme implementation in the 13 countries, the majority achieved sustaining elimination of IDD whilst all had adequate median UIC; however, more detailed studies are still needed to confirm that all communities are equally protected of IDD.

Iodine Status and Association With Gut Health: A Multi-Site Birth Cohort Study in Eight Low- and Middle-Income Countries

Objectives(To 1) describe trends of iodine status among infants from 6–24 mos old and (2) assess associations between iodine status, intestinal permeability, and inflammation from 6–15 mos old. MethodsData from 1565 children enrolled in the MAL-ED birth cohort were included in these analyses from eight sites (Dhaka, Bangladesh (BGD); Fortaleza, Brazil (BRF); Vellore, India (INV); Bhaktapur, Nepal (NEB); Loreto, Peru (PEL); Naushero Feroze, Pakistan (PKN); Venda, South Africa (SAV); and Haydom, Tanzania (TZH)) from enrolment (≤17 d old) to 24 mos old. Urinary iodine concentration (UIC) was measured at 6, 15, and 24 mos of age using the Sandell-Kolthoff technique. Gut inflammation and permeability were assessed via fecal neopterin (NEO), myeloperoxidase (MPO) and alpha-1-anti-trypsin (AAT) concentrations (monthly in first year and quarterly in second) and the lactulose-mannitol (LM) test (3, 6, 9, 15 mos). The mean of fecal biomarkers available up to 94 days (interquartile range: 92–120) preceding the iodine quantification were used. LM values used were contemporary to the iodine sampling (6 and 15 mos). Frequency of household use of iodized salt (I-salt) was recorded. A multinomial regression analysis was used to assess classified UIC (deficiency or excess). ResultsI-salt was used in four sites (BGD, BRF, NEB and PEL), but used by fewer than 20% of families in the others. At 6 mos, all sites had adequate (≥100 mg/L) to excess (≥371 mg/L) median UIC. INV had the lowest median UIC (204 μg/L [95%:171–238]) and NEB had the highest (893 μg/L [95%:762–1026]). Between 6–24 mos, five sites displayed a significant decline in the infant’s median UIC (BRF, BGD and SAV sites were constant). An increase of NEO concentration and LM ratio by + 1 sd were found to reduce the odds of high UIC by 0.87 [95%:0.78–0.96] and 0.88 [95%:0.79–0.98] respectively. ConclusionsExcess UIC was predominant at 6 mos and tended to normalize at 24 mos. Aspects of gut inflammation and increased permeability appear to be protective against high UIC in children aged 6–15 mos. Programs addressing iodine-related health should consider the use and appropriate formulation of I-salt and the role of gut permeability in vulnerable individuals. Funding SourcesThe MAL-ED study was supported by the Bill & Melinda Gates Foundation, with grants to the Foundation for the NIH and NIH/FIC.

Nutritional Iodine Status in Pregnant Women from Health Area IV in Asturias (Spain): Iodised Salt Is Enough.

Background: Iodine deficiency during pregnancy may have adverse effects on the neurodevelopment of the foetus. Recent studies of pregnant women in Asturias (Spain) indicate that nutritional iodine levels are sufficient. The objective of this study was to confirm the appropriate nutritional iodine status and to analyse the influence of the ingestion of iodine on maternal urinary iodine concentration (UIC) and thyroid function. Methods: An observational study was carried out between May and June 2017 on women in the first trimester of pregnancy from Health Area IV in Asturias. The women completed a questionnaire related to their consumption of iodine and samples were taken to analyse UIC and thyroid function. Results: Three hundred and eighteen pregnant women were involved. Of these, 51.10% used iodised salt, 48.90% consumed ≥ 2 servings of dairy products daily and 87.08% took iodine supplements. The median UIC was 171.5 μg/L (116–265 μg/L) and 60.41% of women had UIC ≥ 150 μg/L. Multivariate logistic regression analysis demonstrated that iodised salt had a protective effect on UIC < 150 μg/L (odds ratio (OR) 0.404 (0.237–0.683), p = 0.001), but not iodine supplements (OR 0.512 (0.240–1.085), p = 0.080). The average level of thyroid stimulating hormone (TSH) was 2.26 ± 0.94 mIU/L; 68.40% of pregnant women taking iodine supplements had TSH < 2.5 mIU/L compared to 30.00% of those who were not taking supplements (p = 0.031). Conclusions: The pregnant women in our health area are maintaining appropriate nutritional iodine levels. The consumption of iodised salt protects against iodine deficiency; thus, iodine supplements should be taken on an individualised basis.

Adequate Urinary Iodine Concentration among Infants in the Inland Area of Norway.

Considering the importance of iodine to support optimal growth and neurological development of the brain and central nervous system, this study aimed to assess and evaluate iodine status in Norwegian infants. We collected data on dietary intake of iodine, iodine knowledge in mothers, and assessed iodine concentration in mother’s breast milk and in infant’s urine in a cross-sectional study at two public healthcare clinics in the inland area of Norway. In the 130 mother–infant pairs, the estimated infant 24-h median iodine intake was 50 (IQR 31, 78) µg/day. The median infant urinary iodine concentration (UIC) was 146 (IQR 93, 250) µg/L and within the recommended median defined by the World Health Organization for this age group. Weaned infants had a higher UIC [210 (IQR 130, 330) µg/L] than exclusively breastfed infants [130 (IQR 78, 210) µg/L] and partially breastfed infants [135 (IQR 89, 250) µg/L], which suggest that the dietary data obtained in this study did not capture the accurate iodine intake of the included infants. The iodine status of infants in the inland area of Norway seemed adequate. Weaned infants had higher UIC compared to breastfed infants, suggesting early access and consumption of other sources of iodine in addition to breast milk.

Pregnant Women Are Iodine Deficient While School-Aged Children Demonstrate Adequate Iodine Status in Sarawak, Malaysia.

A mandatory universal salt iodization (USI) has been implemented in Sarawak, Malaysia since 2008. The aim of this study is to assess the current iodine status among school-aged children (SAC) and pregnant women (PW) after 10 years of USI implementation in Sarawak. This cross-sectional survey among school-aged children and pregnant women was conducted between July and October 2018 in Sarawak. The multistage proportionate to population size sampling technique was used to select 30 schools and 30 maternal and child health care clinics. A total of 1200 children aged 8 to 10 years and 750 first-trimester pregnant women were randomly selected to participate in the study. Iodine excretion level in urine was determined according to the World Health Organization classification. A total of 988 children and 677 PW participated in the study with a response rate of 82.3% and 90.2%, respectively. The overall median urinary iodine concentration (UIC) level among the children was 126.0 μg/L (interquartile range [IQR], 71.0-200.9 μg/L) and classified as adequate iodine status. The median UIC among PW was 123.9 μg/L (IQR, 56.5-192.1μg/L) indicating inadequate iodine status. The present findings indicate that despite adequate iodine status in children, the majority of PW still showed inadequate iodine status. Thus, comprehensive monitoring of the iodine deficiency disorder problem among PW is warranted.

Iodine status in women attending Mnazi Mmoja Hospital in Zanzibar: a matched case-control study

BackgroundIodine deficiency can have adverse health effects in all age groups affecting growth, development and cognitive functions as well as the incidence of goitre. Worldwide, the most important dietary source...

Assessment of iodine nutrition of schoolchildren in Gonda, India, indicates improvement and effectivity of salt iodisation.

To study the total goitre rate (TGR), urinary iodine concentration (UIC) and salt iodine content among schoolchildren in a previously endemic area for severe iodine deficiency disorder (IDD). Cross-sectional epidemiological study. The study was carried out in the Gonda district (sub-Himalayan region) of North India. Nine hundred and seventy-seven schoolchildren (6-12 years) were studied for parameters such as height, weight, UIC and salt iodine content. Thyroid volume (TV) was measured by ultrasonography to estimate TGR. The overall TGR in the study population was 2·8 % (95 % CI 1·8, 3·8). No significant difference in TGR was observed between boys and girls (3·5 % v. 1·9 %, P = 0·2). There was a non-significant trend of increasing TGR with age (P = 0·05). Median UIC was 157·1 μg/l (interquartile range: 94·5-244·9). At the time of the study, 97 % of salt sample were iodised and nearly 86 % of salt samples had iodine content higher than or equal to 15 part per million. Overall, TGR was significantly lower (2·8 % v. 31·0 %, P < 0·001), and median UIC was significantly higher (157·1 v. 100·0 μg/l, P < 0·05) than that reported in the same area in 2009. A marked improvement was seen in overall iodine nutrition in the Gonda district after three and a half decades of Universal Salt Iodisation (USI). To sustainably control IDD, USI and other programmes, such as health education, must be continuously implemented along with putting mechanisms to monitor the programme at regular intervals in place.

Relationship Between Iodine Status and Thyroid Function in Preschool Children: From the Environmental and Development of Children (EDC) Study

Background: We investigated iodine status and its association with thyroid function among preschool children residing in iodine-sufficient area. Methods: From the Environment and Development of Children study, 477 children were evaluated for thyroid function and urine iodine concentration (UIC) at age 6 during 2015-2017. After excluding children born with multiple birth and with congenital hypothyroidism or Hashimoto thyroiditis, 439 (231 boys) were included. Subclinical hypothyroidism (SCH) was defined as thyroid stimulating hormone (TSH) levels between 4.9-10 μIU/mL with normal free T4 levels. Iodine status was evaluated by UIC and children were categorized into 4 groups: iodine deficient (UIC < 100 μg/L), adequate (UIC, 100-299 μg/L), mild excessive (UIC, 300-999 μg/L), severe excessive (UIC ≥ 1000 μg/L). Results: Goiter was palpated in 64 (14.6%) with female predominance (26.0% vs. 4.3%, P < 0.001). Serum level of free T4 and T3 was 1.2 ± 0.1 ng/dL and 148.1 ± 18.5 ng/dL, respectively. The median TSH level was 2.3 (0.53-8.59) μIU/mL and the prevalence of SCH was 4.3% without sex-difference. The median UIC level was 606.2 (19.9-16409.7) μg/L, higher in boys (684 vs. 545 μg/L, P = 0.021) than in girls. Iodine was deficient in 19 (4.3%), adequate in 96 (21.9%), mild excessive in 170 (38.7%), and severe excessive in 145 (35.1%). After excluding 19 iodine deficient children, the relationship between iodine status and thyroid function was evaluated by multiple regression analysis after adjusting for age, sex, birth weight, gestational age, body mass index Z-score, and family history. As iodine status increased from adequate, mild excessive to severe excessive group, T3 levels decreased, and TSH levels increased with marginal significance (P for trend < 0.1 for T3 and TSH). When stratified by sex, similar association was found in only girls (P for trend = 0.043 for T3, and 0.062 for TSH) but not in boys, and mild excessive group showed lower free T4 levels (β = -0.05, P = 0.013) and severe excessive group had lower T3 levels (β = -7.04, P = 0.035) than iodine adequate group in only girls, but not in boys. Conclusion: Iodine was deficient in 4.3%, adequate in 21.9%, and excessive in 73.8% among preschool children residing in South Korea. As iodine status increased from adequate to excessive group, TSH levels increased with decreasing free T4 and T3 levels in girls.

The effects of salt consumption habits on iodine status and thyroid functions during pregnancy

Background/aimIodine is the basic substrate for thyroid hormone synthesis and is vital for the general population and especially pregnant women. Iodine deficiency may cause severe health problems for a foetus. This study aimed to determine the relationship, if any, between iodine level and thyroid function tests, and to determine the relationship between consumption of salt types and its effects on thyroid function tests in the first trimester of pregnancy.Materials and methods Three hundred and six pregnant women in the first trimester of pregnancy, who had known no thyroid disease history and had not received iodine supportive therapy, were included in the study. All patients were questioned for their preferred table salt or rock salt in daily use and urine iodine concentrations (UICs) were analysed in spot urine. The results were evaluated statistically according to salt usage preferences.ResultsThe median age of patients in the study was 27.8 (± 5.4). In terms of salt consumption habits, 235 (76.8%) of patients reported using table salt, and 71 (23.2%) reported using rock salt. Iodine deficiency was found in 75.81% (n = 232) of all cases according to urinalysis. Median UICs of table salt group were significantly higher than rock salt group (123.7 μg/L and 70.9 μg/L respectively, P < 0.001). ConclusionAlthough large-scale salt iodination began long time ago, iodine deficiency is still a serious health problem among pregnant women. According to this study, use of rock salt is associated with low urinary iodine concentration in pregnant women and TSH values within the reference limits are not a good indicator for determining the iodine level.

The association of lactating mothers' urinary and breast milk iodine levels with iodine nutrition status and thyroid hormone levels of newborns.

To explore the iodine status of lactating mother-newborn pairs, and whether neonatal serum thyroid-stimulating hormone (TSH) can be used for estimation of iodine status of the population. A total of 334 mothers and their healthy neonates were included. Urine, serum, and breast milk samples were obtained at 4th and 6th days of delivery. Urinary iodine concentration (UIC) was measured in urine samples of mothers and their neonates, as well as breast milk iodine concentration (BMIC) and serum thyroid hormone levels of neonates, were measured from the samples taken between the 4th and 6th days after birth. Median age of the mothers was 27 years (23-30). The median UIC of mothers and their newborns were 125 μg/L and 142 μg/L, respectively. The median BMIC was 138,0 μg/L. There was a significant positive correlation between the BMIC and UIC of neonates (r=0.276, p<0.001). The prevalence of neonatal serum TSH >10 mIU/L, which is suggestive of mild iodine deficiency (i.e. 3.0-19.9%), was 19.0%. However, there were no participants with iodine deficiency in lactating mothers and neonates according to UIC. By previous reports, Aydın is iodine sufficient. Although 19% of the neonates had serum TSH levels >10 mU/L, which is suggestive of a mild iodine deficiency, iodine deficiency was observed in none of the neonates and their mothers. Therefore, it will be appropriate to investigate the role of neonatal TSH levels in a larger sample to assess the iodine status of the population.

Iodine Nutritional Status and Related Factors among Chinese School-Age Children in Three Different Areas: A Cross-Sectional Study.

We evaluated the iodine nutritional status and related factors among school-age children based on the 2016 National Nutrition and Health Surveillance of Children and Lactating Women; 3808 children from Hebei, Guangxi, and Zhejiang province were included in the study. Urinary iodine concentration (UIC), thyroid-stimulating hormone (TSH), body mass index (BMI), vitamin A (VA), and vitamin D (VD) were measured. The abnormal rate of UIC and TSH were assessed. Relationships between UIC/TSH and the possible factors were analyzed. The overall median UIC was 185.14 µg/L, and the median UIC of children aged 8–10 was 164.60 µg/L. Prevalence of iodine deficiency and excess was 13.84% and 14.36%, respectively, and 12.87% of children showed TSH excess. UIC, as well as the abnormal rates of iodine deficiency (ID) and TSH, were significantly different among the three provinces. The median UICs and excess rates increased with age, reaching 211.45 µg/L and 21.35% at age of 14~, while TSH showed the opposite trend. Overweight children tended to have lower UIC and higher TSH. Higher UIC and TSH were found in VA sufficient group (p < 0.01). Further, the VD deficient group had a higher TSH compared to the sufficient group (p < 0.01). Moreover, UI and TSH distribution was obviously different among different vitamin A/D status (p < 0.05). Although the median UIC of school-age children was optimal, there were pockets of inadequate and excessive UI in the three provinces. Compared to the national IDD monitoring results in 2014, the iodine nutritional status of children was greatly improved. Considerations of region, age, BMI, VA, or VD are needed in the future iodine evaluation and surveillance.

Clinical practice guidelines "Management of iodine deficiency disorders"

Iodine deficiency disorders is a sweeping term that includes structural and functional impairment of the thyroid gland.These clinical guidelines include algorithms for the diagnosis and treatment of euthyroid goiter and nodular/ multinodular goiter in adults and children. In addition, these clinical guidelines contain information on methods for an adequate epidemiological assessment of iodine deficiency disorders using such markers as the percentage of goiter in schoolchildren, the median urinary iodine concentration, the level of neonatal TSH, the median thyroglobulin in children and adults. As well from these clinical guidelines, you can get to know the main methods and groups of epidemiological studies of iodine deficiency disorders.

КЛИНИЧЕСКИЕ РЕКОМЕНДАЦИИ "ЗАБОЛЕВАНИЯ И СОСТОЯНИЯ, СВЯЗАННЫЕ С ДЕФИЦИТОМ ЙОДА"

Iodine deficiency disorders is a sweeping term that includes structural and functional impairment of the thyroid gland. These clinical guidelines include algorithms for the diagnosis and treatment of euthyroid goiter and nodular/ multinodular goiter in adults and children. In addition, these clinical guidelines contain information on methods for an adequate epidemiological assessment of iodine deficiency disorders using such markers as the percentage of goiter in schoolchildren, the median urinary iodine concentration, the level of neonatal TSH, the median thyroglobulin in children and adults. As well from these clinical guidelines, you can get to know the main methods and groups of epidemiological studies of iodine deficiency disorders.

Iodine status of postpartum women and their infants aged 3, 6 and 12 months: Mother and Infant Nutrition Investigation (MINI).

To alleviate the re-emergence of iodine deficiency in New Zealand, two strategies, the mandatory fortification of bread with iodised salt (2009) and a government-subsidised iodine supplement for breast-feeding women (2010), were introduced. Few studies have investigated mother and infant iodine status during the first postpartum year; this study aimed to describe iodine status of mothers and infants at 3, 6 and 12 months postpartum (3MPP, 6MPP and 12MPP, respectively). Partitioning of iodine excretion between urine and breast milk of exclusive breast-feeding (EBF) women at 3MPP was determined. In total, eighty-seven mother-infant pairs participated in the study. Maternal and infant spot urinary iodine concentration (UIC) and breast milk iodine concentration (BMIC) were determined. The percentage of women who took iodine-containing supplements decreased from 46 % at 3MPP to 6 % at 12MPP. Maternal median UIC (MUIC) at 3MPP (82 (46,157) µg/l), 6MPP (85 (43,134) µg/l) and 12MPP (95 (51,169) µg/l) were <100 µg/l. The use of iodine-containing supplements increased MUIC and BMIC only at 3MPP. Median BMIC at all time points were below 75 µg/l. Infant MUIC at 3MPP (115 (69,182) µg/l) and 6MPP (120 (60,196) µg/l) were below 125 µg/l. Among EBF women at 3MPP, an increased partitioning of iodine into breast milk (highest proportion 60 %) was shown at lower iodine intakes, along with a reduced fractional iodine excretion in urine (lowest proportion 40 %), indicating a protective mechanism for breastfed infants' iodine status. In conclusion, this cohort of postpartum women was iodine-deficient. Iodine status of their breastfed infants was suboptimal. Lactating women who do not consume iodine-rich foods and those who become pregnant again should take iodine-containing supplements.