Prevalence Of Goiter In Schoolchildren Research Articles

Monitoring of iodine deficiency disorders in the Republic of Tyva

ОбоснованиеОбоснование. Республика Тыва — регион с доказанным тяжелым природным йодным дефицитом и высокой распространенностью ЙДЗ (йододефицитных заболеваний). Однако в регионе в определенные периоды времени предпринимались меры по ликвидации дефицита йода в питании населения. В статье представлены результаты проведенного в октябре 2020 г. специалистами ФГБУ «НМИЦ эндокринологии» Минздрава России контрольно-эпидемиологического исследования, направленного на оценку современного состояния йодной обеспеченности населения Республики Тыва. Исследование проведено по поручению Министерства здравоохранения России в рамках государственного задания «Научная оценка необходимости принятия дополнительных нормативных правовых и иных мер по ликвидации йодного дефицита в пилотных регионах с тяжелым йодным дефицитом» (фрагмент, посвященный контрольно-эпидемиологическим исследованиям в регионе), «Эпидемиологические и молекулярно-клеточные характеристики опухолевых, аутоиммунных и йододефицитных тиреопатий как основа профилактики осложнений и персонализации лечения» (аналитический обзор мероприятий, предшествующих контрольно-эпидемиологическим исследованиям в регионе).ЦельЦель. Оценка йодной обеспеченности населения Республики Тыва.Материалы и методыМатериалы и методы. Исследование проводилось в трех населенных пунктах республики — гг. Кызыл, ­Шагонар, п. Сарыг-Сеп. Обследованы 227 школьников допубертатного возраста (8–10 лет) с проведением сбора анамнеза, осмотра врача-эндокринолога, пальпации щитовидной железы, забора разовых образцов мочи в одноразовые микропробирки типа Эппендорф, с последующей заморозкой до -20–25 °С для дальнейшего определения концентрации йода в моче с помощью церий-арсенитного метода в лаборатории (клинико-диагностическая лаборатория ФГБУ «НМИЦ эндокринологии» Минздрава России). Кроме того, всем школьникам выполнено ультразвуковое исследование щитовидной железы (с использованием портативного ультразвукового аппарата LOGIQe (China) с мультичастотным линейным датчиком 10–15 МГц, в положении лежа). Рост и вес детей определялись по стандартной методике в момент обследования. Проведены сбор образцов пищевой соли, которая используется в семьях школьников, и определение наличия йодата калия в ней экспресс-методом.Родители школьников подписали информированные согласия на проведение обследования детей. Разрешение локального этического комитета ФГБУ «НМИЦ эндокринологии» Минздрава России получено 25 марта 2020 г., № 5.РезультатыРезультаты. Обследованы 227 школьников 8–10 лет. Определена медианная концентрация йода в моче, исследовано наличие йодата калия в пищевой соли и проведено ультразвуковое исследование щитовидной железы с целью уточнения йодной обеспеченности, охвата использования йодированной соли в питании и распространенности зоба.Медианная концентрация йода в моче составила 153 мкг/л, частота зоба — 7,7%, доля йодированной соли — 95,2%.ЗаключениеЗаключение. Показатель медианной концентрации йода в моче свидетельствует об оптимальной йодной обеспеченности ­населения Тывы. Частота зоба у школьников значимо снизилась по сравнению с данными, полученными в ходе предыдущих эпидемиологических исследований. Доля домохозяйств, использующих йодированную соль (­более 90%), свидетельствует об эффективности ­профилактических мероприятий.

Goiter Prevalence in School Children in Three Districts of Jammu Region

BACKGROUND: IDD (Iodine Deficiency Disorders) is still a major public health problem in J&K as in other parts of country despite measures taken to combat it. Repeated surveys are only means to monitor the situation.
 OBJECTIVE: To study the present prevalence of goiter in various districts of Jammu province.
 METHODS: Using EPI 30 cluster methodology, 10800 school children (aged, 6-12 years) were selected from three randomly chosen districts of Jammu province. Subjects were clinically examined and graded for goiter as per joint WHO/UNICEF/ ICCIDD recommendations.
 RESULTS: The goitre prevalence in three districts was observed to be 19.84% with a highest prevalence of 26.75% in Samba district (p = 0.0001). Understandably the prevalence of goitre in age group of 6-9 years was lower than that in 9-12 age group. ( (p=0.005)
 CONCLUSIONS: Total goiter prevalence rate remains to be at an unacceptable high rate. Preventive public health measures need to be augmented in area along with strengthening of monitoring and surveillance of IDD. JMS 2012;15(1):28-31.

Increased goiter prevalence in schoolchildren of Isfahan despite long-term iodine sufficiency

Iodine Deficiency (ID) was for years considered a contributing factor for endemic goiter in Iran. The present study was conducted to assess the goiter prevalence and iodine status in schoolchildren of Isfahan 16 years after the initiation of salt iodization in Iran. 2331 schoolchildren, aged 6-13 years were selected by multistage random sampling. Thyroid size was estimated in each child by inspection and palpation and was graded according to the criteria recommended by WHO. Urinary Iodine Concentration (UIC) was also measured. Overall, 32.9% of the 2331 students had goiter. 4.6% of them were classified as goitrous grade 2. The median UIC was 195.5 microg/l (Range: 10-580 microg/l). 15.8% of total samples had iodine excretion level below 100 microg/l and 3.7% had iodine level below 50 microg/l. UIC in nongoitrous and goitrous children was (mean+/-SD) 220.91+/-119.44 microg/l and 220.16+/-114.64microg/l, respectively (p= 0.949). According to the present study there is no biochemical ID and the iodine intake of the total population is adequate. Goiter prevalence has decreased significantly after the new legislation, nevertheless it is still a public health problem in this region. The data suggest that other goitrogens, micronutrient deficiencies and thyroid autoimmunity may be operative and must be investigated in Isfahan schoolchildren.

Low serum selenium concentration as a possible factor for persistent goiter in Iranian school children

Selenium deficiency can have adverse effect on thyroid metabolism and response to iodine supplementation. The aim of this study was to determine relationship between prevalence of goiter, thyroid hormone profile, urinary iodine and serum selenium concentrations in Iranian schoolchildren. In a cross- sectional study, 1188 schoolchildren in the age group of 8-13 years were evaluated for goiter prevalence. Urine and serum samples were collected from 500 children and assayed for urinary iodine concentration, thyroid hormone profile and serum selenium concentration. The overall goiter prevalence was 39.6% and the median urinary iodine excretion, indicated to an adequate iodine intake. The mean serum selenium concentration was 119.1 +/- 31 mug/l with significant difference between boys and girls (108.4 +/- 26.2 mug/l vs 127.7 +/- 32.1 mug/l). An increase in free T4 concentration was observed in those with a lower selenium level and there was a significant relationship between the presence or absence of goiter and serum selenium concentration. Selenium supplementation may be an advisable measure to optimize thyroid hormone metabolism and decrease the prevalence of goiter in schoolchildren with low serum selenium concentration.

The Relationship of Maternal Iodine Status and Neonatal Thyrotropin Concentration: A Study in Southern Thailand

Iodine deficiency disorder (IDD) is a global health problem. Previous studies in Southern Thailand have shown that the prevalence of goiter in schoolchildren is 3-5%, indicating that Southern Thailand is an iodine sufficient area. We conducted a study in pregnant women to determine their iodine status and whether there was an association between maternal urinary iodine excretion (UIE) and the neonatal thyrotropin (TSH) concentration. We recruited 244 pregnant women attending the antenatal clinic at Songklanagarind Hospital. Their mean age was 28.5 +/- 5.3 years (range 15-42) with a mean gestation age of 9.4 +/- 2.7 weeks (range 6-15). Ten ml urine was collected for UIE measurement. All women were delivered at Songklanagarind Hospital. The mean gestational age at delivery was 38.2 +/- 2.1 weeks (range 28-41). The median maternal UIE was 139.5 microg/l with 78 (32%) women having UIE below 100 microg/l. The median TSH of the infants was 4.14 mIU/l (range 0.30-17.89) with 88 (36.1%) of infants having TSH concentration above 5 mIU/l. Logistic regression analysis revealed that the odds ratio of pregnant women with UIE below 100 microg/l giving birth to infants with neonatal TSH above 5 mIU/l was 2.04 (95% confidence interval 1.17-3.66, p = 0.012). In conclusion, our findings demonstrate that 32% of pregnant women have UIE below 100 microg/l, and that UIE below 100 microg/l in pregnant women is associated with neonatal TSH concentration above 5 mIU/l. These findings suggest that iodine deficiency is prevalent in pregnant women in Southern Thailand.

Ultrasonographic determination of goiter prevalence in southern Brazilian schoolchildren

The aim of the present study was to estimate the prevalence of goiter in schoolchildren in a formerly iodine-deficient region in southern Brazil by assessing the relationship between body surface area (m2 ) and thyroid volume (ml) measured by ultrasonography. A population-based sample of 1,094 randomly selected schoolchildren (6 to 14 years; 556 boys and 538 girls) underwent clinical evaluation. A total of 119 (10.9%) children were diagnosed with goiter upon clinical examination according to WHO criteria (grade Ia: 65, grade Ib: 24, grade II: 29, grade III: 1). Of these, 85 underwent ultrasonography. In order to ascertain the absence of goiter in the 975 schoolchildren with a negative result upon clinical examination, one of ten children was randomly selected for ultrasonography. Sixty-two children agreed to be submitted to the exam. Thus, 147 schoolchildren were evaluated by ultrasonography (7.5-MHz transducer). Goiter was considered to be present when the thyroid volume:body surface area index was >6.2 ml/m . The estimated prevalence of goiter if all schoolchildren had been submitted to thyroid volume measurement by ultrasound was 7.2%; it was higher in the lower socioeconomic class (8.2%) than in the upper (7.8%) and middle classes (6.5%). In conclusion, the prevalence of goiter in schoolchildren of this region was higher than in other iodine-sufficient areas, especially in lower socioeconomic classes. Goiter in this region may be associated with naturally occurring goitrogens that operate more intensively among less privileged individuals.

Iodine deficiency in Calabria: characterization of endemic goiter and analysis of different indicators of iodine status region-wide.

The distribution of goiter prevalence in schoolchildren (no.=13,984, age 6-14 yr), the neonatal TSH results obtained from the congenital hypothyroidism screening program and the urinary iodine excretion values (no.=284) were employed for the assessment of iodine deficiency in Calabria, a Southern Italy region. Data were collected during the years 1990-1996. In the inland territory, goiter prevalence ranged from 19 to 64%. At sea level, there was a great variability of goiter prevalence, with values varying from 5.3 to 25.7%. The analysis of the neonatal hypothyroidism screening program data (no.=21,078) showed a 14.8% frequency of TSH levels >5 microU/ml whole blood in newborns from the inland territory and a 14.1% frequency at sea level. Urinary iodine excretion resulted (mean+/-SD) 53.8+/-43.4 microg/l (range: <20 to 189 microg/l) in the inland territory and 89.6+/-59.8 microg/l (range: 26 to 333 microg/l) at sea level. Median urinary iodine excretion values in 13 villages or small towns of the inland territory ranged from 31 to 57 microg/l. In 2 major towns located at sea level, the median iodine excretion values were 72 microg/l in Crotone main city and 94 microg/l in Reggio Calabria main city. The data indicated that moderate, with pockets of severe iodine deficiency is present in the inland region while iodine supply varies from sufficient to marginally low in the coastal areas. Mild iodine deficiency was found in a major town located at sea level.

Iodine deficiency in Azerbaijan after the discontinuation of an iodine prophylaxis program: reassessment of iodine intake and goiter prevalence in schoolchildren.

The goal of this study was to assess the prevalence of iodine deficiency (ID) in Azerbaijan after the discontinuation of an iodine prophylaxis program by assessing the prevalence of goiter, iodine intake, and thyroid function. The study included 942 schoolchildren (475 boys and 467 girls) ages 8-14 years, from 13 distinct regions. The survey included the following: (1) clinical evaluation; (2) assessment of thyroid volume both by ultrasound and by palpation; (3) determination of iodide in a morning urine specimen using the classic Sandel-Kolthoff reaction in 347 schoolchildren; (4) determinations of thyrotropin (TSH), triiodothyronine (T3), thyroxine (T4), thyroglobulin (Tg), and anti-thyroid peroxidase (TPO) in serum (n = 165) and TSH in whole blood spotted on filter paper (n = 942). The prevalence of goiter for the whole country was determined by ultrasound (US) to be 86% and by palpation 66%, reaching 100% in the mountainous regions of Caucasus. The median urinary iodine excretion (UIE) was 54 microg/L, reaching level of 26 and 39 microg/L in the Caucasus region. In conclusion, according to the World Health Organization (WHO) classification, Azerbaijan now has mild to moderate ID (median UIE, 54 microg/L) and in the mountainous regions with severe ID. The high prevalence of goiter and the low UIE emphasizes the need for urgent medical reintervention. An iodination program is now implemented by our team in the mountainous regions under the auspice of the government of Azerbaijan.

Monitoring the adequacy of salt iodization in Switzerland: a national study of school children and pregnant women

Several countries with long-standing salt iodization programs, including Switzerland, have recently reported declining and/or low urinary iodine (UI) levels in their populations. In Switzerland, in response to studies indicating low UI levels in children and pregnant women, the salt iodine level was increased in 1998 from 15 to 20 mg/kg. Our objective was to evaluate iodine nutrition in a national sample of Swiss school children and pregnant women 8 16 months after the increase in the salt iodine level. A 3-stage probability proportionate to size cluster sampling method was used to obtain a representative national sample of 600 children aged 6-12 y and 600 pregnant women. We then measured UI in both groups, thyrotropin (TSH) in pregnant women and thyroid volume by ultrasound to determine goiter prevalence in school children. The median UI (range) of the children and pregnant women was 115 microg/l (5-413) and 138 microg/l (5-1881), respectively. The median blood TSH concentration (range) of pregnant women was 0.6 mU/l (0.2-2.1). Based on the current WHO/ICCIDD normative data for thyroid volume, none of the children were goitrous, using either age/sex-specific or BSA/sex-specific cutoffs. The iodine status of the Swiss population is once again adequate, illustrating the value of periodic monitoring and prudent adjustments to the iodine level in salt. This approach could serve as a model for countries struggling to maintain dietary iodine intake in the face of shifting dietary habits and changes in the food supply.

Longitudinal study on goiter prevalence and goitrogen factors in northeastern Sicily

A longitudinal study was carried out in an area of endemic goiter of north-eastern Sicily. Three different surveys (in 1977, 1983 and 1994) evaluated the epidemiological prevalence of goiter in schoolchildren of the endemic area (towns of Bronte, Troina and Maniaci) in comparison to an iodine sufficient control area (Catania). Biochemical studies were also performed on urinary iodine and thiocyanate (SCN) excretion and 131I thyroid uptake. In the town of Troina an experimental program of active iodine prophylaxis was carried out from 1979 to 1987 by iodinating the municipal water supply. The aim of this study was to evaluate the effect of an active iodine prophylaxis program in comparison to the "silent iodoprophylaxis" due to improved economic conditions and widespread introduction of industrially produced food. In the 1977-94 period a significant decrease of goiter prevalence in schoolchildren was observed in all areas where no active iodoprophylaxis had been introduced. An abnormal prevalence of goiter, however, was still present in Bronte (12.1%) and Maniaci (25.9%) schoolchildren in respect to Catania (0.7%). In Troina, goiter prevalence decreased from 52.2 to 6.1% after only five years of active iodine prophylaxis (1983). It increased to 8.4% seven years after the program was discontinued (1994). In all areas studied average urinary iodine excretion increased by 70-100 micrograms/day except in the more rural area at Maniaci. During the same period urinary SCN values decreased by 30-40% and were lower in Troina (non volcanic soil) than in other towns studied. The balance between iodine and SCN intake appears a relevant factor in the etiology of endemic goiter in these areas and the iodine/SCN ratio inversely correlated with goiter prevalence. The persistence of endemic goiter in spite of the important changes in life style and socio-economic conditions if compared to the dramatic amelioration obtained by an active iodine prophylaxis program, confirms the inadequacy of the silent iodine prophylaxis, and further supports the need of an immediate introduction of active iodine prophylaxis in the areas of endemic goiter in Sicily.

Current status of endemic goiter in Croatia: the results of a nationwide study (1995).

In the beginning of the nineties, 40 years after introduction of iodine prophylaxis in Croatia, on a basis of a frequent reports coming from general practitioners about the presence of a rather high prevalence of goiter among schoolchildren, a nationwide study was initiated with the aim to determine the real prevalence of goiter in the country. A total of 2856 schoolchildren of both sexes, aged 7-15 years, were included into the study. Investigations were designed in a way to cover most of geographical regions in Croatia and subjects were randomly selected. The prevalence of goiter in schoolchildren was assessed by palpation and in part by ultrasonography of the neck. At the same time urinary iodine excretion was measured and iodine content in salt samples was determined. The results have revealed the persistence of mild endemic goiter in inland parts of Croatia with the prevalence of 6-29% in the age group 7-11 years and those of 10-43% among the age group 12-15 years. The overall goiter prevalence in schoolchildren in Croatia fluctuates from 8% to 35%. Such prevalence, most probably due to less than optimum iodine intake, is unlikely to change until iodine content of the salt is increased from its present level of 10 mg of Kl per kg of salt.

Prevalence of goiter in schoolchildren in Kashmir Valley, India

Prevalence of goiter in schoolchildren in Kashmir Valley, India

Prevention and treatment of endemic iodine-deficiency goiter by iodination of a municipal water supply.

A recently described method for the prevention and treatment of endemic iodine deficiency and goiter, introduction of iodine into a public water supply, was tested in Troina, a town of about 13,000 inhabitants in northeast Sicily. There, before initiation of the program, a goiter endemic of moderate severity was present, as evidenced by goiter prevalence of 55% in school children. Iodine deficiency in nongoitrous adults was indicated by daily urinary iodine excretion of 40.7 +/- 2.6 micrograms (mean +/- SE) and 24-h thyroid radioiodine uptake of 50.8 +/- 2.4%. Iodination of the water supply was initiated in November 1979 using a stream-splitting device that diverts a controlled fraction of the total water flow to a canister containing iodine crystals, where the water becomes saturated with iodine (approximately 300 mg/liter) before returning to the main stream. Except for a 15-month interruption during which governmental authorization of the program was being reconfirmed, treatment of the water has continued to the present time, initially at a level of 81 +/- 25 micrograms/liter (mean +/- SD) and since resumption at a level of 46.5 +/- 5 micrograms/liter. Iodination of the water was followed by a prompt and marked reduction in goiter prevalence, and by improvement in biochemical indices of iodine deficiency. By April 1983, overall goiter frequency in school children had declined to 6.1%, and large goiters (WHO Grade 2) had virtually disappeared. By January 1984, daily urinary iodine excretion had increased to 85.6 +/- 6.5 (SEM) micrograms and radioiodine uptake had decreased to 40.7 +/- 4.7%. Serum thyroid-related hormone concentrations were as follows (pretreatment vs. November-December 1983): T4, 5.8 +/- 0.3 vs. 8.4 +/- 0.3 microgram/dl; T3, 1.6 +/- 0.05 vs. 1.2 +/- 0.06 ng/ml; TSH, 3.7 +/- 0.2 vs. 2.2 +/- 0.1 microU/ml; all changes being statistically significant. By late 1983, serum T4, T3, and TSH values in Troina were almost identical to those in Catania, a community in which iodine deficiency is not present (goiter prevalence in school children, 2.2%). In contrast, in Troina serum T4 concentrations were significantly higher and serum TSH concentrations were significantly lower than those in Maniaci, a iodine-deficient town near Troina, in which the water was not iodinated. Iodinated water was well tolerated by the population of Troina, and no adverse effects of water iodination, including any increase in the frequency of hyperthyroidism, was observed. At present prices, the cost of the water iodination program in Troina would be approximately 4 cents (U.S.) per person per year.(ABSTRACT TRUNCATED AT 400 WORDS)

Role of autoimmune and familial factors in goiter prevalence. Studies performed in a moderately endemic area.

The goitrogenic role of autoimmune phenomena in endemic goiter is still uncertain. Scanty and discrepant results have been reported in different areas of the world. This prompted us to evaluate the prevalence of circulating thyroid antibodies in an area of North-Western Tuscany during a survey for endemic goiter. The survey was carried out according to the P.A.H.O. criteria in a stable community. In all schoolchildren (n = 142, age range 7-15 yr) and in most of their parents (n = 159), thyroid size was evaluated and urine was collected for iodine determination. Blood was drawn for determination of circulating thyroid microsomal (MAb) and thyroglobulin antibodies (TgAb), TT3, TT4 and TSH. Prevalence of goiter in schoolchildren was 77.9% and 94.8% in their parents. Mean (+/- SD) urinary iodine excretion was 55.0 +/- 2.1 micrograms/24 h. The overall frequency of TgAb and MAb in the adult population was 14.4%, statistically higher than that of control subjects matched for sex and age. The frequency in schoolchildren was 4.3%. The presence of goiter in children was unrelated to the presence of thyroid antibodies in parents, whether goitrous or nongoitrous. A higher prevalence of goiter was found in children with goitrous parents as compared to children with nongoitrous parents (p less than 0.005). In conclusion, the frequency of thyroid autoantibodies in the adult population of the endemic area studied was increased, but showed no relation with the presence of goiter. The prevalence of goiter in children was associated with the presence of goiter but not of thyroid autoantibodies in parents. These data suggest that autoimmune phenomena are of limited importance in the development of endemic goiter.