A study on the influencing factors of urinary iodine concentration and the relationship between iodised salt concentration and urinary iodine concentration

The aim of the present study was to explore the influencing factors of urinary iodine concentration (UIC) and the relationship between iodised salt concentration and UIC in order to give suggestions for the surveillance of iodine nutrition status. For this purpose, a multi-stage cluster sampling technique was employed in the present cross-sectional study. Correlations between UIC and salt iodine concentration were evaluated by Spearmen's correlation analysis. Risk factors of having a lower UIC were identified by logistic regression analysis, and the equations of UIC and salt iodine concentration were fitted by curve regression analysis. The median UIC was found to be 162·0 (25th–75th percentile 98·2–248·6) μg/l. The UIC was correlated with salt iodine concentration (Spearman's ρ = 0·144, P< 0·05). The multiple logistic regression analysis found the following influencing factors for having a lower UIC: age (OR 0·98, 95 % CI 0·98, 0·98, P< 0·05); sex (OR 0·81, 95 % CI 0·71, 0·92, P< 0·05); education level (OR 0·87, 95 % CI 0·83, 0·90, P< 0·05); status of occupation (OR 0·91, 95 % CI 0·86, 0·96, P< 0·05); occupation (OR 1·03, 95 % CI 1·00, 1·05, P< 0·05); pickled food (OR 1·24, 95 % CI 1·08, 1·42, P< 0·05); salt iodine concentration (OR 1·03, 95 % CI 1·02, 1·03, P< 0·05). The curve regression analysis found that UIC (y) and salt iodine concentration (x) could be expressed by the following equation: y= 1·5772x1·4845. In conclusion, the median UIC of individuals in Zhejiang Province falls within optimal status as recommended by the WHO/UNICEF/International Council for Control of IDD. To maintain optimal iodine nutrition status, salt iodine concentration should be in the range of 16·4 to 34·3 mg/kg.

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Thyroid dysfunction in region of excess iodine intake of Eastern Nepal

International Journal of Scientific Reports ◽

10.18203/issn.2454-2156.intjscirep20181848 ◽

2018 ◽

Vol 4 (5) ◽

pp. 114

Author(s):

Saroj Thapa ◽

Madhab Lamsal ◽

Rajendra K. Chaudhari ◽

Basanta Gelal ◽

Saroj Kunwar ◽

...

Keyword(s):

Primary School ◽

Subclinical Hypothyroidism ◽

Thyroid Dysfunction ◽

Urinary Iodine ◽

Iodine Concentration ◽

Primary School Children ◽

Nutrition Status ◽

Urinary Iodine Concentration ◽

Iodine Nutrition ◽

Excess Iodine

Background: Iodine deficiency as well as iodine excess can result in an increased prevalence of thyroid disorders. The prevalence of excess iodine nutrition is increasing all over the world. The aim of the present study was to find the occurrence of iodine nutrition status in primary school children of Eastern Nepal and find the prevalence of associated thyroid dysfunction among those with excess urinary iodine concentration.Methods: A community based cross sectional study was conducted in Udayapur district which is located in Eastern part of Nepal. Primary school aged children (6 years to 12 years) were enrolled in this study from three schools. Blood and urine samples were collected and assayed for urinary iodine concentration (UIC), free thyroid hormones (fT3 and fT4), and thyroid stimulating hormone (TSH). Results: The median UIC was 232.27 µg/L. The iodine status showed that 15.5% (n=31) had low UIC, 21% (n=42) had above requirement and 36% (n=72) had excessive iodine nutrition status. The mean concentration of fT3 and fT4 was 2.87 pg/ml and 1.21 ng/dl respectively, while the median TSH concentration was 3.03 mIU/L. The prevalence of thyroid dysfunction was 10% (n=20) with subclinical hypothyroidism being the most common. Majority of participants with subclinical hypothyroidism had excess UIC.Conclusions: Above requirement and excess iodine nutrition is more common in region where there is unregulated consumption and improper monitoring of iodized salt. Subclinical hypothyroidism is common in regions of excess iodine nutrition.

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An epidemiological survey of children's iodine nutrition and goitre status in regions with mildly excessive iodine in drinking water in Hebei Province, China

Public Health Nutrition ◽

10.1017/s1368980012000146 ◽

2012 ◽

Vol 15 (7) ◽

pp. 1168-1173 ◽

Cited By ~ 12

Author(s):

Shengmin Lv ◽

Jun Zhao ◽

Dong Xu ◽

Zhengshui Chong ◽

Lihui Jia ◽

...

Keyword(s):

Drinking Water ◽

Urinary Iodine ◽

Thyroid Volume ◽

Iodine Concentration ◽

Hebei Province ◽

Systematic Sampling ◽

Urinary Iodine Concentration ◽

Iodine Nutrition ◽

Excessive Iodine ◽

Salt Iodine

AbstractObjectiveTo identify children's iodine nutrition and goitre status in areas with mildly excessive iodine in drinking water.DesignA cross-sectional survey. Probability proportional to size sampling was employed to randomly select children from thirty townships where the median iodine content in drinking water ranged from 150 to 300 μg/l; their urinary iodine concentrations were determined and their thyroid volumes were measured by ultrasound. Drinking water samples and salt samples from the villages where the children lived were collected using a systematic sampling method.SettingHebei Province of China.SubjectsA total of 1259 children aged 8–10 years (621 boys and 638 girls).ResultsChildren's median urinary iodine concentration was found to be 418·8 μg/l, and the iodine concentration was >300 μg/l for 68·3 % (248/363) of the urine samples. Children's median urinary iodine concentration in villages with median salt iodine >10 mg/kg was significantly higher than that in villages with median salt iodine <5 mg/kg (442·9 μg/l v. 305·4 μg/l, P ≈ 0). The goitre rate of 1259 children examined by ultrasound was 10·96 %.ConclusionsThe iodine intake of children living in areas with mildly excessive iodine in drinking water in Hebei Province was found to be excessive. The measured iodine excess in the sampled children is exacerbated by consumption of iodized salt. Goitre was identified in these areas; however, due to the limitation of the current criteria for children's thyroid volume, a comprehensive assessment of the prevalence of goitre in these regions could not be made and further study is required.

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Iodine nutrition status in clinically euthyroid pregnant women attending in BSMMU

Bangabandhu Sheikh Mujib Medical University Journal ◽

10.3329/bsmmuj.v9i1.28942 ◽

2016 ◽

Vol 9 (1) ◽

pp. 38

Author(s):

Md. Anowar Hossain ◽

M. Abul Hasanat ◽

Murshed Ahamed Khan ◽

Jobaida Naznin ◽

Kazi Ashraful Alam ◽

...

Keyword(s):

Pregnant Women ◽

Urinary Iodine ◽

Iodine Content ◽

Iodine Concentration ◽

Nutrition Status ◽

Urinary Iodine Concentration ◽

Digestion Method ◽

Iodine Nutrition ◽

Cross Sectional ◽

Nutritional Problem

Background: Iodine deficiency disorders (IDD) are common nutritional problem globally. All groups of people are affected by it, but the pregnant women and their neonates are most vulnerable.Objectives: This study was carried out to see the iodine status of pregnant women using median urinary iodine concentration (MUI) as a measure of outcome. Methods: This cross sectional observational study assessed the MUI in casual urine samples from 225 pregnant women (75 pregnants from each trimester) and 75 non-pregnant healthy controls. The urinary iodine content was estimated in urine sample using the method of Dunn et al. with the modification of Sandell & Kolthoff (wet digestion method).Results: Median value of urinary iodine in pregnant women was 48.21Ug/L compared to 52.27

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IODINE STATUS OF PREGNANT WOMEN RESIDING IN URBAN SLUMS IN DELHI

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2018.v11i7.25002 ◽

2018 ◽

Vol 11 (7) ◽

pp. 506

Author(s):

Spriha Rao ◽

Gurudayal Singh Toteja ◽

Neena Bhatia ◽

Supriya Dwivedi ◽

Zaozianlungliu Gonmei ◽

...

Keyword(s):

Pregnant Women ◽

Urinary Iodine ◽

Urban Slums ◽

Iodized Salt ◽

Nutrition Status ◽

Urinary Iodine Concentration ◽

Iodine Nutrition ◽

Cross Sectional ◽

Iodine Status ◽

Salt Iodine

Objectives: The present study was carried out to determine the iodine nutrition status among pregnant women in slums of West Delhi.Methods: A community-based cross-sectional study was carried out among the third-trimester pregnant women residing in urban slums of West Delhi. Urinary iodine concentration was estimated using ammonium persulfate method, and salt iodine was estimated using iodometric titration.Results: Of the total 180 pregnant women, 70.6% were consuming adequately iodized salt (iodine levels ≥15 ppm). Median urinary iodine level for the pregnant women was 147.5 μg/L indicating iodine deficiency among this group. A total of 51.1% of women had urinary iodine levels <150 μg/L.Conclusion: Pregnant women belonging to slum community from Delhi have a suboptimal iodine status. Further, the proportion of women consuming iodized salt is less than the national average indicating the need to educate these women about the importance of iodine during pregnancy.

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Iodine Status of Taiwanese Population in 2013: 10 Years After Changing From Mandatory to Voluntary Salt Iodization

Food and Nutrition Bulletin ◽

10.1177/0379572117738883 ◽

2017 ◽

Vol 39 (1) ◽

pp. 75-85 ◽

Cited By ~ 2

Author(s):

Fan-Fen Wang ◽

Kam-Tsun Tang ◽

Wen-Harn Pan ◽

Justin Ging-Shing Won ◽

Yao-Te Hsieh ◽

...

Keyword(s):

Age Groups ◽

Urinary Iodine ◽

Iodine Concentration ◽

World Health ◽

Urinary Iodine Concentration ◽

Taiwanese Population ◽

Iodine Nutrition ◽

Iodine Status ◽

Salt Iodization ◽

Health Organization

Background: In 2003, Taiwan’s iodine policy changed from mandatory to voluntary. The Nutrition and Health Survey in Taiwan (NAHSIT) 2001-2002 for schoolchildren showed adequate iodine nutrition, while NAHSIT 2005-2008 for adults showed the iodine status was at borderline adequacy. Objective: To investigate the iodine status of the Taiwanese population from schoolchildren to adulthood 10 years after the change of the salt iodization policy. Method: Urinary iodine was measured in samples from subjects in NAHSIT 2013. Results: The median urinary iodine concentration (UIC) of the Taiwanese population aged 6 years and above in 2013 was 96 μg/L, indicating mild iodine deficiency. The median UIC of 6- to 12-year-old schoolchildren was 124 μg/L (interquartile range [IQR]: 92-213 μg/L), and 115 μg/L (IQR: 80-166 μg/L), 125 μg/L (IQR: 74-161 μg/L), 73 μg/L (IQR: 52-131 μg/L), and 78 μg/L (IQR: 52-132 μg/L) in populations aged 13 to 18 years, 19 to 44 years, 45 to 64 years, and ≥65 years, respectively. Declining iodine nutrition in age groups ≥45 years old was noted that the median UIC of populations aged 45 to 64 years and ≥65 years was 99 and 88 μg/L, respectively, in NAHSIT 2005-2008. The median UIC of schoolchildren was not lower than that during the mandatory salt fortification period, but the distribution of urinary iodine levels signified a dietary pattern change. Conclusion: Wide-ranging variation in iodine nutrition levels was observed in different age groups. Universal salt iodization, as suggested by the World Health Organization, should be the best strategy to achieve adequate iodine nutrition.

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Association between Iodine Nutrition Status and Thyroid Disease-Related Hormone in Korean Adults: Korean National Health and Nutrition Examination Survey VI (2013–2015)

Nutrients ◽

10.3390/nu11112757 ◽

2019 ◽

Vol 11 (11) ◽

pp. 2757 ◽

Cited By ~ 3

Author(s):

Kim ◽

Kwon ◽

Kim ◽

Hong ◽

Park

Keyword(s):

National Health ◽

Thyroid Disease ◽

Urinary Iodine ◽

Iodine Intake ◽

Thyroid Stimulating Hormone ◽

Nutrition Status ◽

Urinary Iodine Concentration ◽

Nutrition Examination Survey ◽

Iodine Nutrition ◽

Health And Nutrition

This study aimed to observe the relationship between iodine nutrition status (dietary iodine intake and estimated iodine intake based on urinary iodine concentration (UIC)) and thyroid disease-related hormones. This study involved 6090 subjects >19 years old with valid UIC, assessed between 2013 and 2015 by the Korean National Health and Nutrition Examination Survey, using a stratified, multistage, clustered probability-sampling design. The estimated iodine intake in participants was measured using UIC and urine creatinine. To examine the effect of iodine intake on thyroid disease, the iodine intake was divided into Korean Dietary Reference Intakes groups, and logistic regression analysis was performed via the surveylogistic procedure to obtain odds ratios (ORs) and 95% confidence intervals (CIs). The estimated iodine intake showed a significant positive correlation with dietary iodine intake (r = 0.021, p < 0.001), UIC (r = 0.918, p < 0.001), and thyroid-stimulating hormone (TSH) (r = 0.043, p < 0.001), but a significant negative correlation with free thyroxine (FT4) (r = −0.037, p < 0.001). Additionally, as the estimated iodine intake increased, age, TSH, and UIC increased, but FT4 decreased (p for trend < 0.0001). The risk of thyroid disease was higher in the “≥tolerable upper intake level (UL ≥ 2400 µg/day)” group than in the “<estimated average requirement (EAR < 150 µg/day)” group in females (OR: 2.418; 95% CI: 1.010–5.787). Also, as iodine intake increased, the risk of thyroid disease increased (p for trend < 0.038).

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Iodine nutrition status of women after 10 years of Lipiodol supplementation: a cross-sectional study in Xinjiang, China

British Journal Of Nutrition ◽

10.1017/s0007114520003918 ◽

2020 ◽

pp. 1-13

Author(s):

Lixiang Liu ◽

Peng Liu ◽

Qin Lin ◽

Xiaohui Su ◽

Jia Huang ◽

...

Keyword(s):

Iodine Deficiency ◽

Urinary Iodine ◽

Thyroid Volume ◽

Nutrition Status ◽

Thyroid Peroxidase ◽

Urinary Iodine Concentration ◽

Free Triiodothyronine ◽

Iodine Nutrition ◽

Detection Rates ◽

Status Of Women

Abstract This study examined the contribution of long-term use of Lipiodol capsules, as a supplement to iodised salt to the control of iodine deficiency disorders among women in Xinjiang of China. A total of 1220 women across Kashgar, Aksu, Turpan and Yili Prefectures were surveyed in 2017. Lipiodol capsules were administered twice yearly in Kashgar and once yearly in Aksu and Turpan, but not in Yili. Urinary iodine concentration (UIC), free triiodothyronine (FT3), free thyroxine (FT4), thyroid-stimulating hormone (TSH), thyroglobulin antibody, thyroid peroxidase antibody and thyroid volume values were assessed. All the women in the four areas were in a state of non-iodine deficiency by UIC. The UIC were higher than adequate in Kashgar and Aksu (619·4 v. 278·6 μg/l). Thyroid hormone levels differed significantly in Turpan and Yili (FT3: 4·4 v. 4·6 pmol/l, FT4: 13·8 v. 14·2 pmol/l, TSH: 2·0 v. 2·7 mIU/l), but did not differ significantly in Kashgar, Aksu and Yili. The four areas did not differ significantly with regard to thyroid nodules, autoimmune thyroiditis or goitre. However, the detection rates of subclinical hypothyroidism (16·6 %) and total thyroid dysfunction (25·4 %) were higher among women in Yili. The supplementation with Lipiodol capsules had improved the iodine nutrition status of women in iodine-deficient areas of Xinjiang since 2006. To avoid negative effects of excess iodine, we suggest a gradual discontinuation of Lipiodol capsules in women with special needs based on the existing iodine nutrition level of local women.

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Larger Thyroid Volume and Adequate Iodine Nutrition in Chinese Schoolchildren: Local Normative Reference Values Compared with WHO/IGN

International Journal of Endocrinology ◽

10.1155/2016/8079704 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 4

Author(s):

Zhe Mo ◽

Xiaoming Lou ◽

Guangming Mao ◽

Zhifang Wang ◽

Wenming Zhu ◽

...

Keyword(s):

Reference Values ◽

Urinary Iodine ◽

Thyroid Volume ◽

Reference Interval ◽

Iodine Concentration ◽

Zhejiang Province ◽

Urinary Iodine Concentration ◽

Iodine Nutrition ◽

Local Reference ◽

Urine Iodine

Objective. Thyroid volume measured by ultrasound to define goiter needs reliable local thyroid volume reference from iodine-sufficient populations. The aim of this study is to explore the reference interval for normal thyroid volume in schoolchildren aged 8–10 years from Zhejiang Province, China.Methods. A probability-proportionate-to-size sampling method was applied to select a representative sample of 1213 children aged 8–10 years in Zhejiang Province to detect the thyroid volume, salt iodine, and urine iodine.Results. Median urinary iodine concentration in involved schoolchildren was 178.30 (125.00) μg l−1, with the percentage of samples less than 100 μg l−1as 12.69% and more than 300 μg l−1as 15.25%. Thyroid volume was significantly correlated with age and anthropometric measurements independently of each other. The 97th percentile of thyroid volume in our study was larger generally than the new international reference.Conclusions. The iodine nutritional status in Zhejiang Province was at an adequate level. Despite some limitations in this study, we initially established the reference values for thyroid volume in 8–10-year-old schoolchildren in Zhejiang Province, China, as a local reference to be used for monitoring iodine deficiency disorders.

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Thyroid stimulating hormone isn’t a sensitive indicator of iodine nutritional status in schoolchildren

Revista de Ciências Médicas e Biológicas ◽

10.9771/cmbio.v14i3.14990 ◽

2016 ◽

Vol 14 (3) ◽

pp. 350

Author(s):

Renata De Oliveira Campos ◽

Joaquim Custódio Silva Júnior ◽

Elton Estrela Ramos

Keyword(s):

Public Schools ◽

Nutritional Status ◽

Filter Paper ◽

Urinary Iodine ◽

Iodine Concentration ◽

Thyroid Stimulating Hormone ◽

Urinary Iodine Concentration ◽

Iodine Nutrition ◽

Cross Sectional ◽

Stimulating Hormone

Introduction: iodine deficiency disorders (IDD) are most common cause of preventable brain damage, mental retardation and stunted growth in children worldwide. Several indicators are complementary to urinary iodine concentration (UIC) for assessing iodine nutritional status, as thyroid size, thyroglobulin (Tg) and thyroid stimulating hormone (TSH) concentrations in the blood. Objective: analyze TSH in filter paper blood values and correlate with UIC in schoolchildren from public school at state of Bahia, Brazil. Methodology: cross-sectional study was conducted in 880 schoolchildren aged 6-14 years, randomly selected, of public schools in five cities of four micro-regions of Bahia between October 2013 and September 2014. TSH was analyzed in filter-paper blood and UIC were measured by adapted Sandell-Kolthoff reaction. Results: 880 blood samples on filter-paper were analyzed for TSH. The reference range previously established is 0.72 to 6.0 μUI/mL. Results of this research TSH dosage ranged from 0.24 μIU/L to 7.71 μIU/L, with a mean of 1.01±0.55 μUI/L and median 0.89 μUI/L. Only one child presented TSH greater than 6.0 (7.71 μIU/L); however, results of urinary iodine were consistent with a more than adequate nutrition iodine (243.70μg/L). There’ no correlation between TSH and UIC (r= 0.115; p= 0.002). Conclusion: in the present study, schoolchildren showed low values of TSH, but the mean UIC was indicative of adequate iodine nutrition.

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Women Remain at Risk of Iodine Deficiency during Pregnancy: The Importance of Iodine Supplementation before Conception and Throughout Gestation

Nutrients ◽

10.3390/nu11010172 ◽

2019 ◽

Vol 11 (1) ◽

pp. 172 ◽

Cited By ~ 8

Author(s):

Kristen Hynes ◽

Judy Seal ◽

Petr Otahal ◽

Wendy Oddy ◽

John Burgess

Keyword(s):

At Risk ◽

Pregnant Women ◽

Iodine Deficiency ◽

Urinary Iodine ◽

Iodine Concentration ◽

Urinary Iodine Concentration ◽

Iodine Nutrition ◽

Supplement Use ◽

Iodine Supplementation ◽

The Impact

In Australia, pregnant women are advised to take an iodine supplement (I-supp) (150 µg/day) to reduce risks to the foetus associated with iodine deficiency (ID). To examine the impact of this recommendation on iodine status, and to identify factors that contribute to adequacy during gestation, supplement use and Urinary Iodine Concentration (UIC) was measured in 255 pregnant women (gestation range 6 to 41 weeks) in Tasmania. The median UIC (MUIC) of 133 µg/L (Inter-quartile range 82–233) was indicative of ID, being below the 150–249 µg/L range for adequacy during pregnancy. Women taking an iodine-containing-supplement (I-supp) had a significantly higher MUIC (155 µg/L) (n = 171) compared to the combined MUIC (112.5 µg/L) (n = 84) of those who had never (120 µg/L) (n = 61) or were no longer taking an I-supp (90 µg/L) (n = 23) (p = 0.017). Among women reporting I-supp use, the MUIC of those commencing the recommended 150 µg/day prior to conception was significantly higher than those starting supplementation following pregnancy confirmation: 196 (98–315) µg/L (n = 45) versus 137.5 (82.5–233.5) µg/L (n = 124), p = 0.032. Despite recommendations for iodine supplementation pregnant Tasmanian women remain at risk of ID. Commencing an I-supp of 150 µg/day prior to conception and continuing throughout pregnancy is required to ensure adequacy. Timely advice regarding the importance of adequate iodine nutrition, including supplementation is needed to reduce the risk of irreversible in utero neurocognitive damage to the foetus.

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