Severity Of Iodine Deficiency Disorders Research Articles

The problem of iodine deficiency in the Chechen republic: assessment of the current state and ways of solution

To conduct a comprehensive study to assess the current iodine security of the population of the Chechen Republic, to analyze the prevalence of thyroid pathology and compare it with official statistics, to formulate conclusions about the necessary preventive measures. In the Chechen Republic, a total of 1239 people were examined, of which 921 were schoolchildren of pre-pubertal age (8-10 years) and 318 were adults. The survey of the adult population was carried out at medical organizations in four districts of the republic (Nadterechny, Shalinsky, Vedensky, Grozny) and included a questionnaire survey, a clinical examination by an endocrinologist with palpation of the thyroid gland, thyroid ultrasound, and a study by a qualitative method of samples of table salt used in households for the presence of iodine.Children's examinations were carried out by the cluster method on the basis of secondary schools in 9 out of 15 districts of the republic and included an examination by an endocrinologist and measurement of anthropometric parameters (height, weight), thyroid ultrasound to evaluate volume, determination of iodine concentration in single portions of urine and qualitative analysis of samples of table salt used in children's nutrition in families for the presence of iodine.The incidence and prevalence of thyroid disease among the population of the Chechen Republic were analyzed using data from official state statistics - form No. 12 «Information on the number of diseases registered in patients living in the area served by the medical institution» (ROSSTAT data as of 01.01.2021). According to the results of a survey of 921 pre-pubertal children, the median urinary iodine concentration was 71.3 µg/L (frequency of values below 50μg/L - 17,7%) and varies from 48.9 to 179.2 µg/L in the surveyed areas. According to thyroid ultrasound data, diffuse goiter was detected in 16.4% of the examined children, with goiter frequency ranging from 11.3% to 23.5%. The proportion of iodized salt consumed in schoolchildren's families was 4.2% in all study areas (range of values from 1.3% to 8%), which indicates an extremely low level of using iodized salt by household.According to the results of the examination of the adult population (n=318), structural changes in thyroid tissue were detected in 79.9% (n=254), while the proportion of nodular thyroid pathology being 83% (n=205), with a range of values across different districts of 52.5-80%. Based on the obtained data, according to WHO criteria, it can be stated that, overall, the degree of severity of iodine deficiency disorders in the Chechen Republic corresponds to mild severity with a tendency towards moderate severity in several districts of the foothills. The results of the examination of the adult population indicate a high prevalence of thyroid pathology, predominantly nodular, in the Chechen Republic. The data obtained in the course of large-scale research made it possible to initiate the development of necessary medical and organizational measures in the region - a program for the prevention of IDD.

Результати епідеміологічних досліджень поширеності йододефіцитних захворювань у Республіці Узбекистан

Актуальність. Незважаючи на проведені заходи, що спрямовані на ліквідацію йодної недостатності, Республіка Узбекистан (РУз) залишається зоною значної поширеності йододефіцитних захворювань. Мета дослідження — вивчення динаміки поширеності йододефіцитних захворювань серед населення в РУз. Матеріали та методи. Поширеність йододефіцитних захворювань серед школярів РУз вивчалася з урахуванням рекомендацій Всесвітньої організації охорони здоров’я. Були проаналізовані такі показники, як поширеність дифузного зоба, йодурія, споживання йодованої кухонної солі. Дані порівнювалися з результатами досліджень попередніх років. Результати. Згідно з показниками йодурії, частка тяжкого дефіциту йоду (менше 20 мкг/л) знизилася з 94,4 % у 1998 році до 21,4 % у 2004 році, до 1,9 % — у 2010 і 2016 роках. Оптимальний рівень споживання йоду (понад 100 мкг/л) збільшився від 0 % в 1998 році до 46,3 % у 2004 році, до 63,7 % — у 2010 і до 76,3 % — у 2016. Порівняльний аналіз поширеності дифузного зоба I і II ступенів показав, що частка даного захворювання становила загалом 72,8 % в 1998 році, 58,8 % — у 2004, 40,2 % — у 2010 і 28,6 % — у 2016. Висновки. Значну роль у прогресі в галузі профілактики йододефіцитних захворювань у РУз відіграв ухвалений у 2007 році закон «Про профілактику йододефіцитних захворювань». Незважаючи на проведені широкомасштабні заходи, дані щодо вмісту йоду в кухонній солі і сечі, отримані у 2016 році, свідчать про те, що 25 % населення РУз все ще залишаються в стані йодного дефіциту.

The status of iodine nutrition and iodine deficiency disorders among school children in Metekel Zone, northwest Ethiopia.

Iodine deficiency disorders are serious public health problems in Ethiopia. The aim of this study was to measure the prevalence and severity of iodine deficiency disorders among school children in Metekel Zone. A cross-sectional school based descriptive study was conducted between February 2011 and July 2012. One school containing 750 children aged between 6 and 18 years was randomly selected. Two hundred students from this school were selected by systematic random sampling. Physical examination was made according to WHO goiter classification system; 50 salt samples from households to which the sampled children belonged were tested for iodine using rapid field test kits and titration; a casual urine sample (5 ml) was taken from 30 children to measure urinary iodine spectrophotometrically, and 5 ml venous blood sample were collected from 37 children to measure thyroid relevant blood constituents using ELISA. The total goiter prevalence was 39.5%; 60% of the salt samples contained no iodine. The median urinary iodine concentration ranged from 20.54 - 62.2 (39.9 µg/L). School children who were assessed for thyroid hormones showed 18.92% elevated and 27.03% suppressed TSH levels. The study demonstrated that iodine deficiency is still a severe public health problem in Metekel Zone. There is a need to further strengthen the existing controlling and monitoring system in order to achieve proper elimination of IDDs in the community.

Prevalence and severity of iodine deficiency disorder among children 6-12 years of age in shebe senbo district, jimma zone, southwest ethiopia.

Iodine deficiency disorder is a major problem worldwide, especially during pregnancy and childhood. The magnitude of the problem is quite big in Ethiopia. The main aim of the present study was to determine the prevalence and severity of iodine deficiency disorders. A cross-sectional survey was conducted in Shebe Senbo District on January 2011. Three elementary schools were selected by lottery method from 20 schools. From each school, students were selected by simple random sampling. Spot urine sample (5 ml) was taken to measure urine iodine level; physical exam was made to palpate goiter and salt samples were collected to estimate iodine content. Out of 389 participants, 179 (46%) were males. The total goiter rate was 59.1% (Grade 1: 35.2%; Grade 2:23.9%). The median urinary iodine level was 56 4g/L that indicates iodine deficiency. Out of 389 households in the study area, 277 (71.2%) were using non-iodinated salt, 102 (26.2%) of the households were using iodinated salt. Cabbage usage was significantly associated with goiter. Endemic goiter is quite prevalent in the study area. Median urinary iodine value of the study samples was found to be far lower than standards. Quality of the salt used by the study population was found to be poor in its iodine content. The use of cabbage (goitrogen) has shown remarkable influence on the development of goiter. Therefore, awareness creation and distribution of iodized salt are highly recommended.

Addressing Widespread Iodine Deficiency Disorders: A Serious Health Problem in Thailand and Beyond

Iodine is the heaviest of all elements essential for human health. Iodine is a constituent of the thyroid hormone that acts on many body systems, and thus, iodine’s effects are quite broad. In discussing iodine deficiency disorders (IDDs), one should rank mental defects and physical impairments ahead of goiter, which is a mere physical disfigurement. Consuming iodide- or iodate-supplemented salt has been the most widely implemented public health measure for people at risk of iodine deficiency. However, millions of people on several continents still suffer today from insufficient iodine intake. Inadequate government enforcement and limited access to supplemented salt are partly responsible for the persistence of this disease. Traditional beliefs and food habits are also contributing factors toward difficulties in lowering the incidence and severity of IDDs. In the multistep process needed for making dry salt, most iodide in seawater is converted to iodine, which sublimates, thus drastically reducing the iodine content. Regular consumption of iodized table salt is a necessity for people, especially those at risk of developing IDDs.

Beneficial effects of iodized salt prophylaxis on thyroid volume in an iodine deficient area of southern Italy

Goitre prevalence in school-age children is an indicator of the severity of iodine deficiency disorders (IDD) in an endemic area. The aims of the present study were (i) to provide ultrasound thyroid volume (TV) reference values in a healthy population of school-children aged 11-14 year living in iodine-sufficient areas of Calabria region (ii) to assess both goitre prevalence and urinary iodine (UI) concentration in all children aged 11-14 year from four mildly iodine-deficient areas in which we have carried out a program of salt iodization and (iii) to evaluate the efficacy of the iodoprophylaxis in an adult population living in a small village of the same endemic area. Cross-sectional and prospective studies. TV was assessed by ultrasonography and iodine intake was estimated by measuring iodine excretion in spot urine samples. Results We provided the ultrasound normal reference values as a function of age and body surface area, which displayed significant differences from those recommended by the World Health Organization. By adopting local criteria, the prevalence of goitre in children ranged from 23.4% to 27.7% normalized for age and body surface area, respectively, while the UI excretion was < 100 microg/l in 38% of subjects studied. In an adult population living in the same endemic area, goitre prevalence was lowest in the 18-27-year-old age group, and increased progressively with age. We propose for the first time local reference ultrasound values for TV in a population of 11-14-year-old school-children that should be used for monitoring IDDs and have demonstrated the beneficial effects of iodoprophylaxis in consistent with reduced goitre prevalence in children and in the young adult population studied.

Iron Deficiency in Goitrous Schoolchildren of Semirom, Iran

Background: Iodine deficiency produces the spectrum of iodine deficiency disorders (IDDs): endemic goiter, hypothyroidism, cretinism, and congenital anomalies. Other factors, including goitrogens and micronutrient deficiencies, may influence the prevalence and severity of IDDs and response to iodine supplementation. This cross-sectional, descriptive study was performed in 2003 on elementary school children of Semirom, a mountainous region of Iran, where goiter was hyper-endemic in 1994, but the goiter prevalence had not decreased as expected many years after salt iodization and iodine injection. Some possible risk factors associated with goiter in that area were evaluated, and the results of iron study are presented here. Methods: 1,869 cases were selected by a multistage cluster sampling procedure. Grade 2 goitrous children were compared with equal number of nongoitrous children for serum iron, ferritin, transferrin, thyroxin, TSH and urine iodine concentrations (UIC). Results: 210 children (105 goiter grade 0 and 105 goiter grade 2) entered this sub-study. Of 210 participants, 70 children had low transferrin saturation, 13 had low serum ferritin and 9 children had both problems. There was no significant difference in goiter rate between children with low iron indices and others.There was no significant correlation between serum iron, ferritin or transferrin saturation with other variables including T4, UIC and goiter stage. Conclusion: The present study reveals that in the area studied, iron deficiency cannot explain the high prevalence of goiter, so other responsible factors should be investigated.

New reference values for thyroid volume by ultrasound in iodine-sufficient schoolchildren: a World Health Organization/Nutrition for Health and Development Iodine Deficiency Study Group Report

Goiter prevalence in school-age children is an indicator of the severity of iodine deficiency disorders (IDDs) in a population. In areas of mild-to-moderate IDDs, measurement of thyroid volume (Tvol) by ultrasound is preferable to palpation for grading goiter, but interpretation requires reference criteria from iodine-sufficient children. The study aim was to establish international reference values for Tvol by ultrasound in 6-12-y-old children that could be used to define goiter in the context of IDD monitoring. Tvol was measured by ultrasound in 6-12-y-old children living in areas of long-term iodine sufficiency in North and South America, central Europe, the eastern Mediterranean, Africa, and the western Pacific. Measurements were made by 2 experienced examiners using validated techniques. Data were log transformed, used to calculate percentiles on the basis of the Gaussian distribution, and then transformed back to the linear scale. Age- and body surface area (BSA)-specific 97th percentiles for Tvol were calculated for boys and girls. The sample included 3529 children evenly divided between boys and girls at each year ( +/- SD age: 9.3 +/- 1.9 y). The range of median urinary iodine concentrations for the 6 study sites was 118-288 micro g/L. There were significant differences in age- and BSA-adjusted mean Tvols between sites, which suggests that population-specific references in countries with long-standing iodine sufficiency may be more accurate than is a single international reference. However, overall differences in age- and BSA-adjusted Tvols between sites were modest relative to the population and measurement variability, which supports the use of a single, site-independent set of references. These new international reference values for Tvol by ultrasound can be used for goiter screening in the context of IDD monitoring.

Monitoring the severity of iodine deficiency disorders in Uganda.

Iodine deficiency disorders (IDD) cover a variety of pathological conditions including goitre, mental retardation and perinatal mortality in millions of individuals globally. IDD was initially identified as a problem in 1970 and was confirmed in 1991. In 1993, the Uganda government introduced a policy of Universal Salt Iodization (USI) requiring all household salt to be iodized. After 5 years this study evaluates the USI programme. To determine goitre prevalence rate, establish the proportion of household consuming iodized salt and determine the levels of iodine intake in the sample districts. A sample of 2880 school children aged 6-12 years from 72 Primary schools in 6 districts of Uganda was studied in October 1999. Goitre was established by palpation, salt iodine was analysed by thiosulphate titration, while urinary iodine was analyzed using ICCIDD recommended method F in which iodine is detected colorimetrically at 410 nm. The over all total goitre rate was 60.2% down from 74.3 in 1991 and visible goitre was 30% down from 39.2% in 1991. The proportion of households taking adequately iodized salt was 63.8% and the median urinary iodine was 310 microg/L. Whereas 36% of 95 urine samples analysed in 1991 had urinary iodine below 50 microg/L, only 5% of the 293 urine samples studied in 1999 had the same urine levels. This represents a considerable improvement in iodine intake, which is confirmed by the fact that 63.8% of the study households consume adequately iodized salt. If maintained and evenly spread, this will enable Uganda to control IDD. USI has improved iodine intake in Uganda. However, iodine malnutrition is still a severe public health problem because some communities in this study such as in Kisoro still have low iodine consumption, while others such as Luwero now have iodine excess. The latter is likely to predispose to hyperthyroidism. The national set standard of household salt iodine of 100 ppm be revised. Locally produced salt be iodized, and a national iodine monitoring programme be instituted to ensure evenly spread consumption of adequately iodized salt by all communities in the country.

Eliminating iodine deficiency disorders

Eliminating iodine deficiency disorders

Study of biochemical prevalence indicators for the assessment of iodine deficiency disorders in adults at field conditions in Gujarat (India)

The main objective of this study was to assess the severity of iodine deficiency disorders (IDD) in the adult populations of the Baroda and Dang districts from Gujarat, western India using biochemical prevalence indicators of IDD. The other aim of this study was to establish a biochemical baseline for adequate iodine intake as a result of program evolution in the face of multiple confounding factors, like malnutrition and goitrogens responsible for goiter. A total of 959 adults (16-85 years) were studied from two districts (Baroda and Dang) and data was collected on dietary habits, anthropometric and biochemical parameters such as height, weight, urinary iodine (UI) and blood thyroid stimulating hormone (TSH). Drinking water and cooking salt were analyzed for iodine content. All subjects, irrespective of sex and district, showed median UI = 73 microg/L and mean blood TSH +/- SD = 1.59+/-2.4 mU/L. Seven per cent of the studied population had blood TSH values > 5 mU/L. Females in Baroda and males from Dang district were more affected by iodine deficiency as shown by a lower median UI. Mean TSH was significantly higher in women from both districts as compared to men (P = 0.001). The blood spots TSH values > 5 mU/L were seen in 20% of women from Dang. The normative accepted WHO values for UI and TSH for the severity of IDD as a significant health problem are not available for target population of adults. Urinary iodine normative limits and cut-offs are established for school-aged children. Blood spot TSH upper limit and cut-off values are available for neonate populations. The IDD has not been eliminated so far, as more than 20% of both male and female subjects had UI < 50 microg/L. Males were more malnourished than females in both districts (P < 0.05). Pearl millet from Baroda contained flavonoids like apigenin, vitexin and glycosyl-vitexin. Dang district water lacked in iodine content. Iodine deficiency disorder is a public health problem in Gujarat, with the Baroda district a new pocket of IDD. High amounts of dietary flavonoids in Baroda and Dang, malnutrition and an additional lack of iodine in Dang water account for IDD.

Thyroid ultrasound is the best prevalence indicator for assessment of iodine deficiency disorders: a study in rural/tribal schoolchildren from Gujarat (Western India).

(i) To assess the severity of iodine deficiency disorders (IDD), (ii) to determine the aetiology of IDD in Gujarat, (iii) to identify the best prevalence indicator of IDD, and (iv) to compare thyroid volume (TV) results with the WHO International reference. Five hundred and thirty schoolchildren (6-15 years) were studied from two districts (Baroda and Dang) and data were collected on dietary habits and parameters such as height, weight, thyroid size by palpation and ultrasonography, urinary iodine (UI), and blood thyroid stimulating hormone (TSH). Drinking water was analyzed for iodine content and food articles for goitrogens. In Gujarat children median UI (interquartile range)=56 (30-96)microg/l, mean TSH=1.71 +/- 2.10mU/l, goiter by palpatio n = 30%, and median TV = 27.8 (23-35)ml. Females had lower median UI (48 (27-82) microg/l) and higher mean TSH levels (2.0 +/- 2.5mU/l) than males. Applying the WHO ultrasonography reference to Gujarat children resulted in an enlarged TV-for-body surface area in almost 100% of subjects. Ninety-nine percent of females and 95% of males had enlarged TV-for-age. Three to eight times larger TV were seen in all subjects as compared with European children. Dang children were severely malnourished. Flavonoids like vitexin, glucosyl vitexin and apigenin were detected in pearl millet. Apigenin was never identified in pearl millet. Dang district water was lacking in iodine content. IDD is a severe public health problem in Gujarat. Baroda district is a new pocket of IDD. High amounts of dietary flavonoids in Baroda and Dang districts, and lack of iodine in Dang water, account for IDD. TV measurement by ultrasound is the best prevalence indicator of IDD.

The epidemiology of iodine deficiency disorders (IDD) in Yemen.

This first nationwide survey was undertaken to estimate the prevalence rates and severity of iodine deficiency disorders (IDD) and the proportion of households consuming iodized salt. The country was stratified into two ecological zones and 30 clusters (primary schools) from each zone, including the required numbers of pupils, were selected randomly. A subsample of pupils provided urine and salt samples for the determination of urinary iodine excretion (UIE) and presence of iodate, respectively. Yemen. There were a total of 2984 pupils aged 6-12 years of whom 2003 were boys and 981 girls. The majority (1800) pupils were from the lowland/coastal areas (zone II) and the rest (1184) from the mountainous regions (zone I). The total goitre rates (TGR) in the whole country, zones II and I were 16.8%, 31.1% and 7.4%, respectively. The TGR in zone I for males was 32.8% and 27.3% for females, while in zone II the corresponding rates were 8.1% and 5.9%, respectively, and the differences were not statistically significant. Only three cases of visible goitres were encountered. The median UIE levels in zones I, II and the whole country were 13.6, 18.9 and 17.3 microg dl-1, respectively. Based on UIE cut-off points recommended by WHO, IDD was severe in 4.7% of pupils in zone I and 2.6% in zone II. Mild and moderate IDD were found in 18.5% and 8.7% of the pupils respectively. Nearly 70% of the surveyed pupils had UIE values of >/= 10 microg dl-1 (no deficiency). Girls had relatively better iodine nutrition as suggested by higher levels of median UIE. In addition, across all age groups median UIE values were above 10 microg dl-1. Over half of the households consumed iodized salt. Since the introduction of universal salt iodization in 1996 both the prevalence and severity of IDD in Yemen were reduced markedly and Yemen can now be classified as a country with a mild IDD problem. However, the low level of households consuming iodized salt may hamper the goal of IDD elimination.

Local versus WHO/International Council for Control of Iodine Deficiency Disorders-recommended thyroid volume reference in the assessment of iodine deficiency disorders.

Iodine deficiency endemia is defined by the goitre prevalence and the median urinary iodine concentration in a population. Lack of local thyroid volume reference data may bring many health workers to use the European-based WHO/International Council for Control of Iodine Deficiency Disorders (ICCIDD)-recommended reference for the assessment of goitre prevalence in children in different developing countries. The present study was conducted in non-iodine-deficient areas in Malaysia to obtain local children's normative thyroid volume reference data, and to compare their usefulness with those of the WHO/ICCIDD-recommended reference for the assessment of iodine-deficiency disorders (IDD) in Malaysia. Cross-sectional thyroid ultrasonographic data of 7410 school children (4004 boys, 3406 girls), aged 7-10 years, from non-iodine-deficient areas (urban and rural) in Peninsular Malaysia were collected. Age/sex- and body surface area/sex-specific upper limits (97th percentile) of normal thyroid volume were derived. Thyroid ultrasonographic data of similar-age children from schools located in a mildly iodine-deficient area, a severely iodine-deficient area, and a non-iodine-deficient area were also collected; spot urines were obtained from these children for iodine determination. The goitre prevalences obtained using the local reference were consistent with the median urinary iodine concentrations in indicating the severity of IDD in the areas studied. In contrast, the results obtained using the WHO/ICCIDD-recommended reference showed lack of congruency with the median urinary iodine concentrations, and grossly underestimated the problem. The local sex-specific reference values at different ages and body surface areas are not a constant proportion of the WHO/ICCIDD-recommended reference. A further limitation of the WHO/ICCIDD-recommended reference is the lack of normative values for children with small body surface areas (<0.8m2) commonly found in the developing countries. The observations favour the use of a local reference in the screening of children for thyroid enlargement.

Urinary Iodine Excretion Is the Most Appropriate Outcome Indicator for Iodine Deficiency at Field Conditions at District Level

To empower local authorities to plan and evaluate adequate interventions, appropriate iodine deficiency disorders (IDD) indicators need to be identified. The aim of this study was to describe the magnitude and severity of IDD with different outcome indicators and associate them with functional indicators. Schoolchildren (n = 544) aged 8–10 y were assessed in 11 villages within five subdistricts of Malang District, East Java, Indonesia. Outcome indicators of IDD were goiter size as measured by palpation and ultrasonography (USG), urinary iodine excretion (UIE) and serum thyroid stimulating hormone (TSH) concentration in blood as well as functional indicators such as intellectual performance (IQ: Catell’s Culture Fair Intelligence Test) and anthropometric indices. The total goiter rate (TGR) measured by palpation and USG were 35.7 and 54.4%, respectively. Based on UIE and TSH, the prevalence of iodine deficiency was 63.7 and 3.4%, respectively. In individuals, goiter, thyroid volume and UIE were associated significantly (r = −0.35; P < 0.001 and r = −0.30; P = 0.02 respectively). Among villages, TGR measured by palpation was significantly correlated with thyroid volume (r = 0.61; P = 0.045) and UIE (r = 0.68; P = 0.021), whereas TSH was not significantly associated with any of the observed indicators in individuals or groups. Multiple regression analysis showed that USG (β = −0.67; P < 0.001) and UIE (β = 4.39; P = 0.008) related significantly with cognitive performance (IQ). The associations between IDD indicators and cognitive performance and height-for-age Z scores suggest that socioeconomically advantaged children had better iodine status. We suggest that UIE is the best indicator for local authorities to assess iodine deficiency.