Earliest prevention of endemic goiter by iodine supplementation during pregnancy

Liesenkötter KP, Göpel W, Bogner U, Stach B, Grüters A. Earliest prevention of endemic goiter by iodine supplementation during pregnancy. Eur J Endocrinol 1996;134:443–8. ISSN 0804–4643 During pregnancy complex changes of maternal thyroid function occur and they are influenced by the maternal iodine supply. It has been demonstrated that with decreasing iodine supply maternal goiter and hypothyroxinemia as well as fetal and neonatal hypothyroidism become more prevalent. Therefore iodine supplementation during pregnancy is now strongly recommended also in areas of moderate iodine deficiency. To monitor the success of iodine supplementation and its theoretical risk of increasing the frequency of thyroid autoantibodies, we have investigated the thyroid volume, thyroid function, urinary iodine excretion and antibodies to thyroid peroxidase at 10–12 weeks of gestation and postpartum in 38 mothers receiving 300 μg potassium iodide/day and in 70 mothers without iodine supplementation. In all of their newborns thyroid volume was determined by ultrasound. The thyrotropin (TSH) levels and antibodies to thyroid peroxidase (TPO-ab) in the neonates were measured in dried blood spots on filter paper from their newborn screening. Urinary iodine excretion was increased significantly after iodine supplementation in mothers (p < 0.001) and their newborns (<0.05). No hypo- or hyperthyroidism was observed in the mothers or newborns. Interestingly, no difference of maternal thyroid volumes was observed between the two groups after pregnancy, but the volumes of the thyroid glands in newborns of mothers who received iodine were significantly (p < 0.004) lower (0.7 ± 0.4 ml) than in the control group (1.5 ± 1.1 ml). There was no change in the frequency of TPO-ab in either group after pregnancy. In four mothers transplacental passage of these antibodies was documented by positive measurement in the blood sample of the newborn. This study documents that iodine supplementation during pregnancy in an area of moderate iodine deficiency results in a lower size of neonatal thyroid volume and that this supplementation was not accompanied by an increase in the frequency of TPO-ab. Klaus Peter Liesenkötter, Kinderklinik Kaiserin Auguste Victoria Haus (KAVH), Virchow-Klinikum der Medizinische Fakultät der Humboldt-Universität zu Berlin, Heubnerweg 6, 14059 Berlin, Germany

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Iodized salt prophylaxis of endemic goiter: an experience in Toscana (Italy)

Acta Endocrinologica ◽

10.1530/acta.0.1290497 ◽

1993 ◽

Vol 129 (6) ◽

pp. 497-500 ◽

Cited By ~ 16

Author(s):

F Aghini-Lombardi ◽

A Pinchera ◽

L Antonangeli ◽

T Rago ◽

GF Fenzi ◽

...

Keyword(s):

Iodine Deficiency ◽

Endemic Goiter ◽

Urinary Iodine ◽

Thyroid Volume ◽

Iodized Salt ◽

Urinary Iodine Excretion ◽

Goiter Prevalence ◽

Iodine Excretion ◽

Health Organization ◽

Legislative Measures

It is well established that iodine supplementation is effective in correcting iodine deficiency and reducing goiter prevalence. In Italy, legislation has allowed the production of iodized salt since 1972, but its consumption is on a voluntary basis. In the present study, the efficacy of legislative measures that made compulsory the availability of iodized salt in foodstores has been evaluated. Urinary iodine excretion and thyroid size, scored according to Pan American Health Organization recommendations, were determined prior to (1981) and 10 years after (1991) the introduction of legislative measures in the whole schoolchildren population residing in a restricted area of the Tuscan Appennines. Moreover, in 1991, thyroid volume was determined by ultrasonography. In 1981, mean urinary iodine excretion was 47.1±22.4 mg/kg creatinine (0.412 μmol/l) and goiter prevalence was 60%, indicating a moderate iodine deficiency. Eighty of the families subsequently used iodized salt on a regular basis; as a result of this excellent compliance, in 1991 the mean urinary iodine excretion increased to 129.7±73 mg/kg creatinine (1.24 μmol/l) and goiter prevalence dropped to 8.1%. The results of this study underline the effectiveness of iodine prophylaxis in correcting iodine deficiency and abating endemic goiter in schoolchildren, and suggest that implementation of measures that make compulsory the availability of iodized salt in foodstores overcomes the fact that there is no law governing the exclusive production and trading of iodized salt.

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The predominant form of non-toxic goiter in Greece is now autoimmune thyroiditis

Acta Endocrinologica ◽

10.1530/eje.0.1400505 ◽

1999 ◽

pp. 505-511 ◽

Cited By ~ 47

Author(s):

AG Doufas ◽

G Mastorakos ◽

S Chatziioannou ◽

S Tseleni-Balafouta ◽

G Piperingos ◽

...

Keyword(s):

Iodine Deficiency ◽

Endemic Goiter ◽

Previous History ◽

Urinary Iodine ◽

Urinary Iodine Excretion ◽

Thyroid Peroxidase ◽

The Past ◽

Iodine Supplementation ◽

Predominant Form ◽

Toxic Goiter

Endemic non-toxic goiter (NTG) in Greece has been attributed primarily to iodine deficiency. Thirty years ago about 60% of the prepubertal boys and girls examined in endemic goiter regions presented with NTG and among them thyroid autoimmunity was rarely detected. Although iodine supplementation has corrected this deficiency during the past 30 years, new cases of NTG still appear. To evaluate the prevalence and type of NTG and the effect of iodine supplementation on them in Greece at present, we performed two cross-sectional clinical studies and a retrospective pathology one: (i) thyroid gland volume and urinary iodine excretion (UIE) were assessed in a representative sample of 1213 schoolchildren from previously endemic and non-endemic regions; (ii) serum thyroxine, tri-iodothyronine, TSH, thyroid autoantibodies (AAB) (anti-thyroid peroxidase and anti-thyroglobulin antibodies) and UIE (in 60 patients) were measured in 300 consecutive patients with NTG from Athens and Heraklion; and (iii) we compared the prevalence of autoimmunity among fine needle aspiration smears of benign thyroid pathologies performed by the same pathologist between 1985 and 1986 (975 cases) and between 1994 and 1995 (2702 cases). We found that 12. 5% of the schoolchildren examined in regions with a previous history of endemic goiter had NTG, whereas this percentage was only 1.7% in areas without such a history. In Athens (61.6%) and Heraklion (58. 5%) a substantial number of NTG patients were AAB positive and biochemically hypothyroid. UIE in Athens did not differ between patients with autoimmune goiter (ATG) and simple goiter. The prevalence of autoimmune stigmata in pathology smears has increased from 5.94% (years 1985-1986) to 13.91% (years 1994-1995) (P<0.05). We conclude that: (i) the persistence of endemic goiter in regional foci despite iodine deficiency correction suggests a possible role for a naturally occurring goitrogen; (ii) ATG is the predominant form of NTG in Greece nowadays; and (iii) the five-fold decrease in the prevalence of NTG during the past 30 years followed by the increase of ATG may support the relative character of the latter.

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Chronic iodine excess does not increase the incidence of hyperthyroidism: a prospective community-based epidemiological survey in China

Acta Endocrinologica ◽

10.1530/eje-06-0651 ◽

2007 ◽

Vol 156 (4) ◽

pp. 403-408 ◽

Cited By ~ 27

Author(s):

Fan Yang ◽

Zhongyan Shan ◽

Xiaochun Teng ◽

Yushu Li ◽

Haixia Guan ◽

...

Keyword(s):

Urinary Iodine ◽

Iodine Intake ◽

Urinary Iodine Excretion ◽

Thyroid Peroxidase ◽

Community Based ◽

Iodine Excess ◽

Iodine Supplementation ◽

Excessive Iodine ◽

Iodine Excretion ◽

Excessive Iodine Intake

Objective: An increasing incidence of hyperthyroidism has been observed when iodine supplementation has been introduced to an iodine-deficient population. Moreover, the influence of chronic more than adequate or excessive iodine intake on the epidemiological features of hyperthyroidism has not been widely and thoroughly described. To investigate the influences of different iodine intake levels on the incidence of hyperthyroidism, we conducted a prospective community-based survey in three communities with mild-deficient, more than adequate (previously mild deficient iodine intake), and excessive iodine intake. Subjects and methods: In three rural Chinese communities, a total of 3761 unselected inhabitants aged above 13 years participated in the original investigation and 3018 of them received identical examinations after 5 years. Thyroid function, levels of thyroid peroxidase antibody (TPOAb), thyroglobulin antibody and urinary iodine excretion were measured and thyroid ultrasound examination was also performed. Results: In three communities, median urinary iodine excretion was 88, 214, and 634 μg/l (P<0.05) respectively. The cumulative incidence of hyperthyroidism was 1.4, 0.9, and 0.8% (P>0.05) respectively. Autoimmune hyperthyroidism was predominant in thyroid hyperfunction in all the three cohorts. Either positive TPOAb (>50 U/ml) or goiter in original healthy participants was associated with the occurrence of unsuspected hyperthyroidism in 5 years (logistic regression, OR=4.2 (95% CI 1.7–8.8) for positive TPOAb, OR=3.1 (95% CI 1.4–6.8) for goiter). Conclusion: Iodine supplementation may not induce an increase in hyperthyroidism in a previously mildly iodine-deficient population. Chronic iodine excess does not apparently increase the risk of autoimmune hyperthyroidism, suggesting that excessive iodine intake may not be an environmental factor involved in the occurrence of autoimmune hyperthyroidism.

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Thyroid volume and morphology and urinary iodine excretion in a Danish municipality

Acta Endocrinologica ◽

10.1530/acta.0.1290505 ◽

1993 ◽

Vol 129 (6) ◽

pp. 505-510 ◽

Cited By ~ 32

Author(s):

Birte Nygaard ◽

Peter Gideon ◽

Harriet Dige-Petersen ◽

Niels Jespersen ◽

Karsten Sølling ◽

...

Keyword(s):

Urinary Iodine ◽

Thyroid Volume ◽

Entire Group ◽

Urinary Iodine Excretion ◽

Thyroid Disorder ◽

Who Grade ◽

Iodine Supplementation ◽

Ultrasound Study ◽

Group I ◽

Iodine Excretion

In order to throw light upon the eventual need for iodine supplementation in Denmark, four age groups of women (15, 30, 45 and 60 years) from the Holbaek municipality were invited for a clinical and ultrasound study of thyroid volume, structure and function. Of the 570 women invited, 391 accepted and were divided into the following groups: group I: 15 years, N= 113; group II: 30 years, N= 100; group III: 45 years, N=98; group IV: 60 years, N=80. The results were as follows: the thyroid gland was palpable in 39% and visible in 16% of the entire group; 19% had a family history of thyroid disorders and 7.6% had a previous thyroid disorder. Thyroid volumes (median (range)) as measured by ultrasound were 12 ml (4–29 ml), 18 ml (5–47 ml), 18 ml (7–64 ml) and 18 ml (9-51 ml) in groups I– IV, respectively. The calculated 24-h iodine excretion was 65 μg (19–365 μg), 88 μg (15-274 μg), 97 μg (40–737 μg) and 83 μg (50–999 μg) in groups I–IV, respectively. An abnormal echo structure was present in 3, 10, 21 and 30%, respectively. Defining a goitre as a thyroid volume above 28 ml indicated a goitre prevalence of 17% in females aged 30–60 years in the Holbaek area of Denmark. Among the 60-year-old women, 3% had a clinically significant goitre (WHO grade III). Thyroid volume did not correlate with iodine excretion. The benefit of iodine supplementation is discussed.

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Serum TSH and serum thyroid peroxidase antibody fluctuate in parallel and high urinary iodine excretion predicts subsequent thyroid failure in a 1-year study of patients with untreated subclinical hypothyroidism

Acta Endocrinologica ◽

10.1530/eje-07-0407 ◽

2008 ◽

Vol 158 (2) ◽

pp. 209-215 ◽

Cited By ~ 10

Author(s):

Jesper Karmisholt ◽

Peter Laurberg

Keyword(s):

Thyroid Function ◽

Subclinical Hypothyroidism ◽

Urinary Iodine ◽

Time Shift ◽

Urinary Iodine Excretion ◽

Thyroid Peroxidase ◽

Thyroid Peroxidase Antibody ◽

Iodine Excretion ◽

Symptoms And Signs ◽

Serum Tsh

ObjectiveTo explore the possibility of predicting decline or improvement in thyroid function over 1 year, and to investigate the correlations of serum TSH (s-TSH) with hypothyroidism-related symptoms and signs, serum thyroid peroxidase antibody (s-TPO-Ab) and urinary iodine excretion in individual patients with untreated subclinical hypothyroidism (SH).DesignMonthly repeated measurement study without intervention.MethodsTwenty-one patients without former thyroid disease who had been identified with s-TSH between 5 and 12 mU/l and normal serum thyroxine (s-T4) at two occasions were enrolled. Subsequently, 13 monthly measurements of s-TSH, hypothyroidism-related symptoms and signs, serum free T4, s-TPO-Ab and urinary iodine excretion were performed.ResultsOver the study year, s-TSH increased significantly in 5 patients, 16 had unchanged s-TSH, whereas none improved. From clinical and biochemical inclusion data, it was not possible to predict who would later increase in s-TSH. In individual patients, a highly significant correlation between s-TSH and s-TPO-Ab was found (r=0.37, P<0.0001) and also between s-TSH and urinary iodine excretion (r=0.14, P=0.034). No correlation between s-TSH and clinical symptoms and signs was observed. Time shift showed best correlation between s-TSH and s-TPO-Ab measured at the same time point, whereas urinary iodine excretion correlated best to s-TSH and s-TPO-Ab obtained 1 month later.ConclusionAt the time of inclusion, it was not possible to identify the 24% of SH patients who would show deterioration in thyroid function over the following year. Impairment in thyroid function varied in parallel with thyroid autoimmunity, whereas high urinary iodine excretion predicted high s-TSH and s-TPO-Ab 1 month later.

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The Effects of Iodine Supplementation in Pregnancy on Iodine Status, Thyroglobulin Levels and Thyroid Function Parameters: Results from a Randomized Controlled Clinical Trial in a Mild-to-Moderate Iodine Deficiency Area

Nutrients ◽

10.3390/nu11112639 ◽

2019 ◽

Vol 11 (11) ◽

pp. 2639 ◽

Cited By ~ 4

Author(s):

Simona Censi ◽

Sara Watutantrige-Fernando ◽

Giulia Groccia ◽

Jacopo Manso ◽

Mario Plebani ◽

...

Keyword(s):

Thyroid Function ◽

Iodine Deficiency ◽

Harmful Effect ◽

Urinary Iodine ◽

Thyroid Volume ◽

Iodine Intake ◽

Controlled Clinical Trial ◽

Iodine Supplementation ◽

T1 And T2 ◽

Single Blind

Background: Iodine supplementation during pregnancy in areas with mild-to-moderate iodine deficiency is still debated. Methods: A single-center, randomized, single-blind and placebo-controlled (3:2) trial was conducted. We enrolled 90 women before 12 weeks of gestation. From enrollment up until 8 weeks after delivery, 52 women were given an iodine supplement (225 ug/day, potassium iodide tablets) and 38 were given placebo. At recruitment (T0), in the second (T1) and third trimesters (T2), and 8 weeks after delivery (T3), we measured participants’ urinary iodine-to-creatinine ratio (UI/Creat), thyroid function parameters (thyroglobulin (Tg), TSH, FT3, and FT4), and thyroid volume (TV). The newborns’ urinary iodine concentrations were evaluated in 16 cases. Results: Median UI/Creat at recruitment was 53.3 ug/g. UI/Creat was significantly higher in supplemented women at T1 and T2. Tg levels were lower at T1 and T2 in women with UI/Creat ≥ 150 ug/g, and in the Iodine group at T2 (p = 0.02). There was a negative correlation between Tg and UI/Creat throughout the study (p = 0.03, r = −0.1268). A lower TSH level was found in the Iodine group at T3 (p = 0.001). TV increased by +Δ7.43% in the Iodine group, and by +Δ11.17% in the Placebo group. No differences were found between the newborns’ TSH levels on screening the two groups. Conclusion: Tg proved a good parameter for measuring iodine intake in our placebo-controlled series. Iodine supplementation did not prove harmful to pregnancy in areas of mild-to-moderate iodine deficiency, with no appreciable harmful effect on thyroid function.

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Iodine status and thyroid parameters of pregnant women living in an iodine sufficient area

Archive of Food and Nutritional Science ◽

10.29328/journal.afns.1001026 ◽

2021 ◽

Vol 5 (1) ◽

pp. 001-006

Author(s):

Delshad Hossein ◽

Mirmiran Parvin ◽

Mehran Ladan ◽

Tohidi Maryam ◽

Azizi Fereidoun

Keyword(s):

Pregnant Women ◽

Iodine Deficiency ◽

Urinary Iodine ◽

Thyroid Volume ◽

Urinary Iodine Excretion ◽

Third Trimester ◽

Group I ◽

Iodine Excretion ◽

The Mean ◽

Group Ii

During the last few decades painstaking efforts have been made to eliminate iodine deficiency throughout the world. Todays in regions where dietary iodine intake is adequate or borderline, the main focus is increasing dietary iodine supply in the target population during pregnancy and the first years of life. Objective: The aim of this study was to obtain longitudinal data on urinary iodine excretion and the changes of maternal thyroid parameters in two groups of healthy women with mild-to-moderate iodine deficiency and iodine sufficiency residing in an iodine replete area of Tehran capital city of IR Iran, for more than one decade. Research designs and methods: The present study is part of a cohort study, investigating the relative influences of iodine intake on thyroid size and function of mothers and their infants during and after pregnancy. A total of 500 pregnant women enrolled from two mother-child health care centers and was divided into group I, with median urinary iodine excretion (MUIE) < 150 µg/L, and group II with MUIE ≥ 150 µg/L. Sonographic thyroid volume measurement, urinary iodine excretion and thyroid function tests were measured sequentially in all pregnant women during the three trimesters (T) of pregnancy. Results: The mean ± SD age of the participants was 25.1 ± 5.1 years. The MUIE in group I and II in the first, second and third trimester were 123 and 250 µg/L, 127 and 166 µg/L, 120 and 150 µg/L, respectively. The MUIE in the third trimester of pregnancy in group I did not differ significantly from the values in the first and second trimesters (p = 0.67), but it did decline significantly in group II (p < 0.001). The median thyroid volume of subjects, in the first, second and third trimesters were 7.8, 8.2 and 8.1 ml in group I and 7.5, 8.0 and 8.4 ml in group II, respectively. No difference in thyroid volume was found between two groups in each of the three trimesters of pregnancy (p > 0.05). The mean (± SD) TSH concentration of subjects in first, second and third trimester was 2.3(± 2.6), 2.1(± 1.8), 2.3(± 1.7) mIU/L in group I and 2.1(± 3.1), 2.1(± 1.8) and 2.0(± 1.3) mIU/L in group II, respectively. The trend of TSH rising in group I was 26.7% and in group II it was 13.3%. The mean TSH value in three trimesters did not differ significantly in either groups (p > 0.05). The mean (± SD) total T4 concentrations of subjects in first, second and third trimesters were 13.2(± 3.4), 13.8(± 3.3), 13.0(± 2.9) µg/dl in group I and 13.1(± 3.2), 13.7(± 2.9), 13.4(± 3.2) µg/dl in group II, respectively. The mean total T4 value in three trimesters did not differ significantly in either groups (p > 0.05). There was no correlation between the thyroid volume and three observed parameters (UIE, total T4 and TSH) during the pregnancy in either groups. Conclusion: Even in areas with well-established universal salt iodization program, pregnancy could be a risk of having iodine deficiency and systematic dietary fortification needs to be implemented in this vulnerable group.

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The degree of reliability of ultrasound and palpation diagnostics of endemic goiter

Problems of Endocrinology ◽

10.14341/probl11741 ◽

1999 ◽

Vol 45 (2) ◽

pp. 24-28

Author(s):

A. V. Dreval ◽

T. S. Kamynina ◽

O. A. Nechaev ◽

A. V. Streltsova ◽

R. S. Tishenin ◽

...

Keyword(s):

Iodine Deficiency ◽

Endemic Goiter ◽

Ultrasonic Method ◽

Urinary Iodine ◽

Moscow Region ◽

Urinary Iodine Excretion ◽

Flat Structure ◽

Ultrasonic Examination ◽

Iodine Level ◽

Iodine Excretion

A population of adult residents of the Stupino district in the Moscow region is examined. Urinary iodine excretion was measured, the thyroid examined by the ultrasonic method and by palpation, and serum TTH measured. Moderate decrease of iodine excretion with the urine (median iodine level in the urine was 91.7%) \ig/liter) indicates a slight iodine deficiency. Palpation revealed enlargement of the thyroid, which was confirmed by ultrasonic examination only in 25%) cases. The highest percentage of disagreements was observed only in first-degree enlargement, the least in third-degree enlargement according to О. V. Nikolaev ’s classification. As for the types of ultrasonic structure of the gland determined by the ratio of its linear parameters (flat, triangular, and cone-like), the highest percentage of disagreements was observed in cases with the flat structure, which is the most incident (77.3%)). Subclinical hypothyrosis was detected in 3%o subjects with iodine deficiency. Only 26%) residents of the examined region regularly consume iodinated salt with food.

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Urinary Iodine Excretion and Serum Thyroid Function in Adults After Iodinated Contrast Administration

Thyroid ◽

10.1089/thy.2015.0024 ◽

2015 ◽

Vol 25 (5) ◽

pp. 471-477 ◽

Cited By ~ 24

Author(s):

Sun Y. Lee ◽

Donny L.F. Chang ◽

Xuemei He ◽

Elizabeth N. Pearce ◽

Lewis E. Braverman ◽

...

Keyword(s):

Thyroid Function ◽

Urinary Iodine ◽

Urinary Iodine Excretion ◽

Contrast Administration ◽

Iodinated Contrast ◽

Iodine Excretion

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Evolution of thyroid autoimmunity during iodine prophylaxis--the Sri Lankan experience

Acta Endocrinologica ◽

10.1530/eje.0.1490103 ◽

2003 ◽

pp. 103-110 ◽

Cited By ~ 36

Author(s):

G Mazziotti ◽

LD Premawardhana ◽

AB Parkes ◽

H Adams ◽

PP Smyth ◽

...

Keyword(s):

Thyroid Autoimmunity ◽

Urinary Iodine ◽

Thyroid Volume ◽

Urinary Iodine Excretion ◽

Thyroid Peroxidase ◽

Sri Lankan ◽

Anthropometric Measures ◽

Thyroid Autoantibody ◽

Iodine Prophylaxis ◽

Goitre Prevalence

OBJECTIVE: To study the evolution of thyroid autoimmunity, in relation to the change in goitre prevalence, during 3 Years of iodine prophylaxis in Sri Lanka. METHODS: Two groups of Sri Lankan schoolgirls between the ages of 10.8 and 17.5 Years were studied in 1998 (401 girls) and 2001 (282 girls). A prospective study was performed in 42 schoolgirls who were thyroid autoantibody (Ab)-positive (+ve) in 1998. Anthropometric measures, urinary iodine excretion (UIE), thyroid Volume, free thyroxine, free tri-iodothyronine, TSH, and thyroglobulin (Tg) and thyroid peroxidase (TPO) Ab were evaluated in all 683 girls. RESULTS: Goitre prevalence was significantly lower in 2001 compared with 1998 related to age (2.9% compared with 20.2%) and body surface area (11.6% compared with 40.8%), although UIE was unchanged. Prevalence of thyroid Ab in 2001 was also lower (23.4% compared with 49.9%); among those with the Ab, 34.8% had TgAb alone and 46.9% had a combination of TgAb+TPOAb, compared with 82.0% TgAb alone in 1998. In 2001, subclinical hypothyroidism was more frequent in Ab+ve (6.3%) than Ab-negative girls (1.0%). A cohort of 42 Ab+ve schoolgirls in 1998 (34 with TgAb alone, eight with TgAb+TPOAb) were evaluated again in 2001. Only 10 of them (23.8%) remained Ab+ve (mostly TPOAb+/-TgAb) in 2001. CONCLUSIONS: This study demonstrates that: (1) in 2001, goitre prevalence and thyroid autoimmunity rates were significantly lower than in 1998; (2) the pattern of thyroid Ab was different in the two surveys; (3) in 2001 alone, the occurrence of hypothyroidism was correlated with the presence of thyroid autoimmunity. These results indicate an evolution of thyroid autoimmune markers during the course of iodine prophylaxis, which has not been described before.

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