Epidemiology of goiter in Auvergne]

An epidemiological study about goiter, related to the French national survey concerning school children aged 10-16, was carried out in region Auvergne. The prevalence of goiter was 12.52%, including 2.8% patients with WHO stages I and II, thus being slightly below national average (16.7%). Iodine urinary excretion was 62.9 +/- 34.3 micrograms per gram creatinine (French mean value 85.0), although sometimes major variation was noted in the same area. Later, two studies were performed in adults, in two places of Haute-Loire and Puy-de-D?me, respectively Arsac-en-Velay and Besse-en-Chandesse. Both places were selected because of high frequency of goiter in children. Prevalence in adults was 16.1% in Arsac-en-Velay including 12.5% stages I and II, and 8.9% in Besse-en-Chandesse including 5.9% stages I and II. Mean iodine urinary excretion was respectively 59.78 micrograms/gram creatinine and 43.45 micrograms/liter. Thus, these surveys confirm a significant prevalence of goiter in Region Auvergne, with endemic places, and a generally low iodine urinary excretion.     

Neuropsychological assessment in schoolchildren from an area of moderate iodine deficiency

Neuropsychological assessment was carried out in schoolchildren from a montane area of Eastern Tuscany (Tiberina Valley). This area was found to be moderately iodine deficient (mean urinary iodine excretion: 39 micrograms/g creatinine), with a cumulative goiter prevalence of 51.9% in schoolchildren aged 6-14 yr (goiter prevalence in the control iodine-sufficient area: 5.6%). No significant differences in serum TT4, TT3, FT4I, TSH levels between the endemic and control areas were found, whereas serum thyroglobulin values were significantly higher in the iodine-deficient area (61 +/- 8 vs 17 +/- 1 ng/ml, p less than 0.01). No differences were found as to the height, body weight and pubertal development in the two areas. Neuropsychological assessment, performed in a representative sample of 50 schoolchildren from the endemic area and 50 schoolchildren from the control area, matched for age, sex and socioeconomical conditions, failed to show major differences between the two groups in the global neuropsychological performance and cognitive levels. However, minor but significant differences were noted in the information vocabulary and coding subtests, at least in children aged 8. Although familial cultural influences might play a role, it would appear that some marginal impairment, with particular regard to motor-perceptual functions, be present in areas of moderate iodine deficiency.     

The role of thiocyanate in the etiology of goiter in an industrial metropolitan area

OBJECTIVE: Thiocyanate (SCN-) has concentration dependent antithyroid properties and a role in the etiology of goiter has been suggested in several studies. In 1991 an epidemiological survey conducted in the region of Halle/Leipzig (Saxony), an area with significant air pollution, suggested an inverse relationship between urinary iodine (I-)/SCN- excretion and goiter prevalence. 10 years later, we reinvestigated the same industrial area to clarify if the situation has changed after the elimination of most industrial waste products and moreover, if SCN- excretion levels alone or in combination with air pollution or smoking as a SCN- source are critical for thyroid function. DESIGN AND METHODS: We investigated a cohort of 708 probands for I-, SCN- and creatinine excretion in spot urine samples and determined the prevalence of goiter and thyroid nodules by high resolution ultrasonography. RESULTS: Probands with goiter (n = 79, 11%) had significantly higher urinary SCN- excretions than probands without (3.9 +/- 2.8 vs 3.1 +/- 3.4 mg SCN-/g creatinine) and significantly lower urinary I-/SCN- ratios than patients without thyroid disorders (41 +/- 38 vs 61 +/- 71 microg I-/mg SCN-/l). Mean urinary I- excretions were not different between probands with or without goiter. Smokers showed significantly elevated urinary SCN-/creatinine ratios in comparison to non-smokers (4.3 +/- 4.3 vs 2.4 +/- 2.1 mg SCN-/g creatinine). ANOVA revealed a prediction of thyroid volume through age (P < 0.001), gender (P < 0.001), body weight (P < 0.05) and smoking (P < 0.05). CONCLUSIONS: In our investigation, age, gender and smoking (raising SCN- levels by CN- inhalation) were predictive for thyroid volume and the urinary I-/SCN- ratios were able to detect probands with an increased risk of developing goiter in contrast to urinary I- excretion levels alone. These data suggest, that in an era and area of decreased cyanide pollution, SCN- may remain a cofactor in the multifactorial aetiology of goiter.     

Selenium and goiter prevalence in borderline iodine sufficiency

DESIGN: Selenium (Se) is required for the biosynthesis of selenocysteine-containing proteins. Several selenoenzymes, e.g. glutathione peroxidases and thioredoxin reductases, are expressed in the thyroid. Selenoenzymes of the deiodinase family regulate the levels of thyroid hormones. For clinical investigators, it is difficult to determine the role of Se in the etiology of (nodular-)goiter, because there are considerable variations of Se concentrations in different populations as reflected by dietary habits, bioavailability of Se compounds, and racial differences. Moreover, most previous clinical trials which investigated the influence of Se on thyroid volume harbored a bias due to the coexistence of severe iodine deficiency in the study populations. METHODS: Therefore, we investigated the influence of Se on thyroid volume in an area with borderline iodine sufficiency. First, we investigated randomly selected probands for urinary iodine (UI) and creatinine excretion in spot urine samples and determined the prevalence of goiter and thyroid nodules by high-resolution ultrasonography. After this, we determined urinary Se excretion (USe) in probands with goiter as well as in matched probands without goiter. Adjustments between the two compared groups were made for age, gender, history of thyroid disorders, smoking, and UI excretion. RESULTS: The mean USe and UI rates of all 172 probands were 24 micro g Se/l or 27 micro g Se/g creatinine and 96 micro g I/l or 113 micro g I/g creatinine indicating borderline selenium (20-200 micro g/l) and iodine (100-200 micro g/l) sufficiency of the study population. Probands with goiter (n=89) showed significantly higher USe levels than probands with normal thyroid volume (n=83; P < 0.05). USe rates were not influenced by present smoking or pregnancy. CONCLUSIONS: In our investigation, USe was not an independent risk factor for the development of goiter. The higher USe in probands with goiter in comparison with probands with normal thyroid volume is most likely a coincidence. Se does not significantly influence thyroid volume in borderline iodine sufficiency because the iodine status is most likely the more important determinant.     

Goiter prevalence and urinary iodide excretion in a formerly iodine-deficient region after introduction of statutory lodization of common salt.

The objective of this epidemiologic study was to determine the volume of the thyroid gland as well as urinary iodine excretion in dependence on age and gender in a population from an area of low natural iodine supply now receiving iodine prophylaxis. In 430 persons from three communities in the province of Carinthia, Austria, we determined thyroid volume via sonography as well as urinary iodide excretion. As in numerous other European countries, natural iodine supply is insufficient in Austria. Therefore, to reduce goiter incidence, iodization of common salt with 10 mg potassium iodide (KI) per kilogram of NaCl was made mandatory in Austria in 1963 by federal law. In 1990, the amount of iodine addition was increased to 20 mg KI per kilogram of NaCl. Our results show that mean urinary iodide excretion in the persons investigated was altogether satisfactory (males: 163.7 microg of iodine per gram of creatinine; females: 183.3 microg of iodine per gram of creatinine). Goiter prevalence was 34.3% in women and 21.3% in men. An increase in goiter occurrence with age was noted in both genders. The increase in goiter prevalence was particularly obvious in the age group older than 40, i.e., among those participants who had spent at least a certain span of their lives in an area of iodine deficiency. Thus, the most likely reason for the persistently high goiter prevalence is not current iodine deficit but rather the high number of goiters that had developed previously at the time of iodine deficiency and were unable to undergo regression in spite of today's comparatively good iodine supply situation.     

Goiter size and thyroid function in an endemic goiter area in northern Italy

Thyroid function was studied in a large number of subjects residing in Varsi, a town in the province of Parma, Italy. In this area, endemic goiter associated with moderate iodine deficiency [59 +/- 3 (+/- SE) microgram iodine/g creatinine], as defined by WHO criteria, affects 65% of the population. Serum T4, T3, thyroglobulin (Tg), and TSH concentrations were measured by RIA in 1218 subjects. The TSH response to TRH was determined in 108 subjects selected randomly from the groups with different grades of goiter. No significant change in serum T4 concentrations was found in subjects with different grades of goiter. Serum T3 concentrations were higher in subjects with the larger goiters. Serum Tg concentration progressively increased, and serum TSH progressively decreased with increasing goiter size. The TSH response to TRH was diminished in subjects with larger goiters. The findings of decreasing serum TSH concentrations and blunted TSH responses to TRH as goiter size increased suggest the possibility of autonomous thyroid function in the larger goiters in subjects residing in this area of moderate iodine deficiency.     

Partial beneficial effects of the so called "silent iodine prophylaxis" on iodine deficiency disorders (IDD) in northeastern Sicily endemia

The prevalence of goiter among schoolchildren and the daily urinary iodine excretion in the general population were evaluated in 4 municipalities in the endemic goiter area in Northeastern Sicily in two different surveys. The first, carried out in 1977-1978, covered 2,493 (91%) schoolchildren; the second, in 1987-1988, covered 2,167 (92%) schoolchildren. A dramatic decrease in goiter prevalence was apparent in each community as follows: in Castell'Umberto (3,904 inhabitants, altitude 641/750 m above sea level) goiter prevalence (G) decreased from 79.7% to 44.2% with a percent reduction (%r) of 44.5 and an increase in 24-h urinary iodine excretion (UIE) from 22.3 +/- 16.4 micrograms/24 h (n = 30) to 48.7 +/- 43.4 (n = 50). A similar trend was apparent in Tortorici (10,194 inhabitants, 475/700 m) where G decreased from 62.2 to 26.5% (% r 57.4) with a UIE increase from 28.4 +/- 29.6 (n = 35) to 47.6 +/- 59.3 (n = 40); in Sinagra (3,387 inhabitants, 300 m) where G decreased from 61.6 to 32.7% (% r 46.9) and UIE increased from 26.0 +/- 21.1 (n = 25) to 66.6 +/- 69.6 (n = 102) and in Sant'Angelo di Brolo (5,732 inhabitants, 380 m) where G decreased from 48.7 to 27.5% (% r 43.5) and UIE increased from 26.3 +/- 16.7 (n = 30) to 47.7 +/- 73.8 (n = 34). These events are clearly related and certainly dependent on the changed alimentary habits in the area due to the improved distribution of frozen food and industrially prepared dairy products, eventually enriched by iodine.(ABSTRACT TRUNCATED AT 250 WORDS)     

Ultrasound scanning assessment of L-thyroxine treatment effectiveness in a group of children with diffuse goiter.

Ultrasound scanning is an accurate and objective method to assess thyroid volume; therefore it is useful to evaluate the effectiveness of L-thyroxine treatment in reducing goiter size, especially in children where clinical evaluation is inaccurate. In this prospectic study we evaluated the effectiveness of one-year L-thyroxine treatment in a group of children with nontoxic diffuse goiter coming from an area with low iodine intake. We examined 11 children (7 females, 4 males), age range 9-14 years. At clinical examination, 6 patients had a goiter classified Ia (according to WHO criteria), 4 had a class Ib and only 1 had a class II goiter. In order to achieve an accurate goiter evaluation, the thyroid volume was determined by ultrasonic scanning with a 5 MHz linear probe before and after treatment. Patients were given a dose of L-thyroxine (1.5-2.0 micrograms/kg/die) in order to significantly reduce serum TSH levels (from 1.8 +/- 0.6 to 0.8 +/- 0.5 mU/l, mean +/- SD). Patients were reexamined at 12 months of therapy and again at 10 months after therapy withdrawal. A significant reduction of the goiter volume (greater than 20%) was obtained in 6/11 (54%) patients, although serum TSH levels were fully suppressed only in one. The mean goiter size reduction in "responders" was -31.2 +/- 9.3% (m +/- SE). After therapy withdrawal goiter size increased in the majority of cases (in 4/11, greater than 20%). Our study demonstrates that L-thyroxine treatment is effective in reducing goiter size in the majority of children with a diffuse goiter.(ABSTRACT TRUNCATED AT 250 WORDS)     

Enhanced iodine concentrating capacity by the mammary gland in iodine deficient lactating women of an endemic goiter region in Sicily.

Iodine balance during pregnancy and lactation was investigated by measuring iodine concentration in the urine of 11 pregnant women, born and living in a moderately iodine deficient endemic goiter area in Northeastern Sicily, collected during the last week of pregnancy, and between the 5th and 7th day after delivery, and in their milk sampled simultaneously with the urine of their newborns. The results were compared with those obtained on similar samples from 16 euthyroid age-matched nongoitrous women and their offspring from an iodine sufficient area. Urinary iodine concentration in pregnant women from the endemic area (1.28 +/- 0.13 micrograms/dl, mean +/- SE) was significantly lower than that of pregnant women from the iodine sufficient area (3.77 +/- 0.57 micrograms/dl) (t = 3.56, p less than 0.005). The longitudinal measurement of iodine concentration in each nursing woman showed a marked increase (approximately 90%) when compared with the values obtained during pregnancy in both endemic and control groups (2.32 +/- 0.36 and 7.76 +/- 2.08 micrograms/dl; t = 2.13 p less than 0.05, respectively). The slight difference in milk iodine concentration between the endemic (3.25 +/- 0.77 micrograms/dl) and the control (4.33 +/- 0.57 micrograms/dl) group was not statistically significant (t = 1.14; p less than 0.5, NS). Similarly no difference was found in urinary iodine excretion between the endemic and the control newborn groups (3.41 +/- 0.76 and 4.30 +/- 0.65 micrograms/dl, respectively, t = 0.88 p less than 0.1, NS).(ABSTRACT TRUNCATED AT 250 WORDS)     

Thyroid autoimmunity is associated with higher urinary iodine concentrations in an iodine-deficient area of Northwestern Greece.

Northwestern Greece was identified in the 1960s for its high prevalence of endemic goiter and iodine deficiency. Although iodized salt has been commercially available since then, a recent epidemiological survey of 3916 schoolchildren found that low-grade goiter is still prevalent in endemic proportions (21%). The aim of this study was to further assess the cause of goiter and the severity of iodine deficiency in children from this endemic area of Greece. Of the 800 children with clinically detectable goiter, 97 children (60 girls and 37 boys, 8-15 years) were recruited for determination of urinary iodine excretion, as well as assessment of thyroid volume and function and detection of antithyroid antibodies. The median urinary iodine concentration was 8.4 microg/dL, indicative of a mild iodine deficiency. Thyroid function was normal in all but 11 children who had subclinical hypothyroidism. Sixteen children (16.5%), including all those with subclinical hypothyroidism, were positive for antithyroid antibodies. Their median urinary iodine concentration (20.6 microg/dL) was higher compared to children who were negative for antibodies (7.4 microg/dL; p<0.001). The mean thyroid volume by ultrasonography (12.2+/-4.1 mL) was above the upper limit of normal for this age group. Thyroid volume was inversely related to the urinary iodine content in the children with negative antithyroid antibodies. Iodine deficiency is still prevalent in northwestern Greece although of mild severity and constitutes the primary cause of goiter among schoolchildren. However, it appears that autoimmune thyroiditis is emerging as a frequent cause of goiter in those children with sufficient iodine intake.     

New area of endemic goiter : the northeast Bénoué, (North Cameroon)

Endemic goiter was thought to essentially spread in the southern part of Cameroun. In fact the North-East Benoué (NEB) area also appears to be concerned. We studied 1242 individuals from 5 representative villages. The overall goiter frequency was 28.4%. Study of emigrants showed a spreading of the endemic area towards the boundary part of Tchad. However increase of morbidity was related to the duration of settlement in NEB (18% after 1 year vs 34% after 5 years, p less than 0.01). Samples of urine from one single micturition were kept at 4 degrees C and assayed for iodide within 3 days. The results exhibited marked iodine deficiency (iodide : 9.6 +/- 1.5 micrograms/l; urinary ratio : iodide/creatinine : 17.9 micrograms/l). The way of preserving urine before iodine assay was critical. After 8 days of daylight exposure of the samples at 30 degrees C, the most part of assayable iodine had disappeared. The goitrogenic effect of manioc was weak : there was no relationship between the presence of goiter and the amount of ingested manioc. Concentration of thiocyanates in urine was correlated neither with manioc consumption nor with goiter volume. An automatic classification was obtained by computerization of several parameters. 88% of the patients distributed in 10 groups whose goiter frequencies were markedly different. Because of the well-defined characteristics of each group, it seems possible to perform valid biological or nutritional studies using a limited number of individuals.     

Assessment of goiter in an area of endemic iodine deficiency.

Urinary iodone (UI) excretion and sonographically measured thyroid volume were investigated in 195 subjects living in 6 separate villages in the Casamance region of southeastern Senegal, West Africa. A comparison of goiter prevalence using thyroid palpation and volume measurement and of iodine excretion expressed as micrograms per gram (microg/g) creatinine or micrograms per deciliter (microg/dl) urine was undertaken, and possible pathogenetic factors were investigated. Ultrasound measured thyroid volumes were above the recommended upper limit of the reference range for an area replete in iodine in 83.1% or females, 52.3% of males, and 80.0% of children aged 13 years or younger. Overall sensitivity and specificity for palpation compared to sonographically demonstrated thyroid enlargement was 51.7% and 91.5%, respectively. Thyroid enlargement was not associated with ethnic origin, thiocyanate ingestion, HLA DR/DQ phenotype frequency, or thyroid growth-stimulating immunoglobulin (TGI) positivity. Median UI was 32 microg/g creatinine with 65.0% having values consistent with iodine deficiency (< 50 microg/g). When results were expressed as micrograms per deciliter, the percentage having values consistent with iodine deficiency (< 5.0 microg/dl) increased to 95.7%. The findings suggest a primary role for iodine deficiency in goitrogenesis in the study population. They demonstrate that classification of the severity of the endemia in this or other study populations in areas of iodine deficiency is dependent on the methods used to determine goiter prevalence (palpation or ultrasound measured thyroid enlargement), or dietary iodine status (iodine excretion expressed as micrograms per gram creatinine or micrograms per deciliter urine).     

Clinical picture of endemic cretinism in central Apennines (Montefeltro).

Endemic cretinism is still present in an endemic goiter area of the central Apennines (Montefeltro) (goiter prevalence 55%; mean urinary iodine level 39 micrograms/g creatinine). Clinical and biochemical features of patients with myxedematous, neurologic, and mixed cretinism were studied. Also, in this area, as in most other, neurologic cretinism is more prevalent than myxedematous and mixed forms. The hormonal profiles of the three types of cretinism were clearly different. Nevertheless, all myxedematous cretins had some neurologic disorders (hyperreflexia, increased muscle tone, disorder of gait, Babinski sign, hypoacusia) that were similar to those present in neurologic cretins. These findings suggest that neurologic damage is very similar in all forms of endemic cretinism, reflecting a diffuse insult to the developing fetal nervous system. Furthermore, these data support the hypothesis that the primary pathophysiologic event in the different types of endemic cretinism is represented by maternal and fetal hypothyroidism, while differences may be explained by the extent and duration of postnatal hypothyroidism. All the cretins were over 35 of age, suggesting a severe iodine deficiency in the past decades, and a progressive improvement of nutritional status resulted in "silent iodine prophylaxis." However, recent studies have revealed the persistence of a moderate iodine deficiency, a high prevalence of neurologic hypoacusia, and reduction of mental performance in normal schoolchildren of this area. These findings constitute strong evidence in favor of adequate iodine prophylaxis.     

Dietary iodine deficiency in East Germany following introduction of interdisciplinary preventive use of iodine

The interdisciplinary iodine prophylaxis introduced in 1985/86 comprises the iodination of 84% of the packaged salt with 32 mg KIO3/kg salt and the use of iodized mixtures of mineral substances in animal production. At the beginning of this measure with an average renal ioduria of 19.0 +/- 1.0 micrograms J/g creatinine in the GDR there was at least still an iodine deficiency of 2nd degree. It increased from north to south: 20.3 +/- 1.0 in contrast 13.4 +/- 1.5 micrograms J/g creatinine. In the middle of 1986 a clear improvement of the supply with iodine began. The renal iodurias had more than doubled. For the GDR the mean ioduria was 43.4 +/- 0.9. The relation from north to south had, if anything, inverted: 37.3 +/- 2.1 in the north, 42-49 micrograms J/g creatinine in the centre and south of the GDR. Nearly one third of the population no more undergoes an iodine deficiency. The intrathyroidal iodine content increases. The improved supply with iodine among others is evident in: reduction of the connatal goiter below 1%, reduction of the recall rate in the TSH hypothyroidism newborn screening, normal thyroid gland mass of the newborn, reduction of the goiter frequency in children and adolescents, transient increase of the frequency of hyperthyroidism, in particular based on functional autonomies in persons older than forty years. In animal production losses of produce amounting to 181 Mic/a were eliminated.     

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.     

The impact of 25 years of iodine prophylaxis on the adult thyroid weight in Finland

The effect of iodine prophylaxis on endemic goiter was studied in an adult Finnish population by comparing autopsy records from 1959 and 1984. In the 1950's the iodine intake calculated both from urinary excretion of stable iodine and from food analysis data was 50-70 micrograms per day the intake being lower in the main endemic area in the eastern part of the country. The use of iodized salt raised these figures only by 15 micrograms per day. At the beginning of the 1980's the iodine intake calculated in the same way was around 300 micrograms per day all over the country. Initially 696 records from 1959 and 525 from 1984 were analyzed. Excluded were cases with primary or secondary malignant thyroid tumors, autopsies with incompletely recorded thyroid weight, and autopsies from patients submitted to pituitary or thyroid surgery or radiation therapy. Finally, 318 cases from 1959 and 478 from 1984 were accepted. A significant decrease in thyroid weight from a mean of 44 to a mean of 34 g was observed. The difference between the two populations was most marked in the age groups below 45 yr. In these age groups the mean thyroid weight was about 20-27 g which can be regarded as normal. In the age groups over 75 years there were no significant differences. These data indicate that the iodine prophylaxis gradually eradicates the endemic goiter in Finland but that it requires still some 25-35 yr before it has disappeared also in the oldest age groups.     

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)     

Serum 3,5,3'-triiodothyronine, thyroxine, and thyrotropin in hypothyroid infants with congenital goiter and the response to iodine.

Iodine deficiency in adults caused preferred synthesis of T3; this observation has not been reported in iodine-deficient hypothyroid newborns. Serum total T4, total T3, and TSH have been determined in nine full term newborns with congenital hypothyroid goiter before and after cutaneous application of iodine. The mothers of these infants had untreated euthyroid goiter and lived during pregnancy in the area of G?ttingen, West Germany, known as an iodine-deficient region. Mean total T4 in the newborns was 6.3 +/- 1.6 (mean +/- SD) micrograms/dl compared to 16.6 +/- 3.4 micrograms/dl in normal newborns at 3-4 days of age. Mean T3 in the goitrous newborns was 2.74 +/- 0.66 ng/ml compared to 1.58 +/-0.41 ng/ml in the control group of the same age. Serum TSH remained elevated during the first week of life, with a concentration of 40.9 +/- 28.7 microU/ml (control group, 4.16 +/- 1.43 microU/ml). The cutaneous application of iodine resulted in rapid disappearance of goiter and normalization of T4 and TSH within 5 days. After 30 days of iodine treatment, T3 decreased slowly but remained elevated (2.0 +/- 0.42 ng/ml vs. 1.67 +/- 0.36 ng/ml in the control group). The present findings confirm preferential T3 secretion in newborns with hypothyroid goiter. The goiter is thought to be caused by intrauterine iodine deficiency, because hypothyroid values of T4 and TSH normalized during iodine treatment. General iodine prophylaxis of the population is recommended.     

Urinary iodine excretion in a geographically stratified Danish population sample not affected by iodination programmes. A change towards higher values

The excretion of urinary iodine was studied in a representative population sample from the county of Funen, Denmark, comprising 505 persons between 25-44 years of age, stratified according to geography, age, and sex. Urine samples were collected for 5 h during late afternoon and early evening. The 24-h iodine excretion was estimated on the basis of iodine and creatinine determinations using correlation equations determined in a pilot study of 50 men and women. The iodine excretion was significantly higher in men: 89 micrograms/24 h (median) than in women: 76 micrograms/24 h; the whole population: 85 micrograms/24 h. No significant differences were observed among the age groups studied. The iodine excretion was significantly higher in people living on small islands: 98 micrograms/24 h (median) compared with 84 micrograms/24 h in urban regions and 78 micrograms/24 h in rural districts. Median iodine excretion per gram of creatinine was 58.8 micrograms for the whole sample. The iodine excretion for men was 77% higher than reported in an earlier investigation performed in Funen, 1969, but still lower than internationally recommended (WHO).     

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.