OBJECTIVE: This study explored whether thyroglobulin and thyroid disease prevalence rates were higher in pregnant Chinese women with a median urinary iodine concentration of 100-149 µg/L, compared with those with a median urinary iodine concentration of 150-249 μg/L maintained through sustainable universal salt iodization. METHODS: This was a cross-sectional study in which 812 healthy pregnant women were enrolled to collect samples of their household edible salt, urine, and blood during their routine antenatal care in the 18 counties in Fujian Province, China. The levels of salt iodine concentration, urinary iodine concentration (UIC), free triiodothyronine (FT3), free thyroid hormone (FT4), thyroid-stimulating hormone (TSH), thyroglobulin (Tg), thyroid peroxidase antibody and thyroglobulin antibody were assessed during the routine antenatal care visits. RESULTS: The median UIC (mUIC) in pregnant women was 130.8 μg/L (interquartile range = 91.5-198.1 μg/L) in the counties with an mUIC of 100-149 μg/L (Group I), and 172.0 μg/L (interquartile range = 123.5-244.4 μg/L) in the counties with an mUIC of 150-249 μg/L (Group II). Goiter prevalence and thyroid nodule detection rates showed no difference between Group I and Group II ( P > 0.05). Except for FT4 values, the TSH, FT4, FT3, Tg and Tg values > 40 (μg/L) and the thyroid diseases prevalence rate (TDR) showed no significant differences between Group I and Group II ( P > 0.05), whether or not iodine supplementation measures were taken. CONCLUSION Compared with an mUIC of 150-249 μg/L, not only there was no difference in thyroid morphology, but also the Tg value, rate of Tg values > 40 µg/L, and TDR were not higher in pregnant women in the counties with an mUIC of 100-149 μg/L achieved through sustainable universal salt iodization in Fujian Province, China.
Female ; Humans ; Pregnancy ; Cross-Sectional Studies ; Iodine/urine* ; Pregnant Women ; Sodium Chloride, Dietary ; Thyroglobulin ; Thyroid Gland ; Thyrotropin ; East Asian People

BACKGROUND: Before iodination of Swedish table salt in 1936, iodine deficiency resulting in goitre and hypothyroidism was common. Sweden has become iodine sufficient, as shown in a national survey in 2007, proving its iodination fortification programme effective for the general population. The objective of this study was to collect drinking water from water treatment plants nationally and test if water iodine concentration (WIC) correlated to urinary iodine concentration (UIC) of school-aged children in a national survey 2007 to former goitre frequency in 1929 and to thyroid volume data in 2007. METHODS: In 2012, 166 treatment plants, located in 57% (166 of 290) of all Swedish municipalities, were asked to collect drinking water samples of approximately 10 ml. In 2007, tap water samples of the same volume were collected from 30 randomly selected schools for the national survey. Analysis of WIC was done in both treatment plants in 2012 (n = 166) and tap water in 2007 (n = 30). The correlation of WIC to the children's UIC and thyroid volume after iodination was tested based on data from the national survey in 2007. The association of WIC to former goitre frequency was tested based on pre-iodination data, derived from a map of goitre frequency drawn in 1929. RESULTS: The median WIC from water treatment plants was 4.0 μg/L (range 0-27 μg/L). WIC was similar in coastal and inland areas, for both ground and surface water. WIC correlated with historical goitre areas and was lower in the goitre areas than in non-goitre areas (p < 0.001). WIC in the same municipalities as the schools correlated with the UIC of children (p < 0.01), but not with their thyroid volume. CONCLUSIONS WIC still contributes to iodine nutrition in Sweden, but iodination overrides the goitre effect.
Adolescent ; Child ; Drinking Water ; chemistry ; Female ; Food, Fortified ; analysis ; Goiter ; epidemiology ; history ; History, 20th Century ; History, 21st Century ; Humans ; Iodine ; analysis ; urine ; Male ; Sodium Chloride, Dietary ; analysis ; Sweden ; epidemiology ; Thyroid Gland ; anatomy & histology

Adult ; China ; Female ; Humans ; Iodine ; administration & dosage ; urine ; Maternal Nutritional Physiological Phenomena ; Nutritional Status ; Pregnancy ; Sodium Chloride, Dietary ; Urinalysis ; methods

Adult ; Female ; Humans ; Hyperthyroidism ; drug therapy ; metabolism ; Iodine Radioisotopes ; pharmacokinetics ; therapeutic use ; urine ; Male ; Middle Aged ; Models, Biological ; Radiation Dosage ; Radiation Monitoring ; Radiopharmaceuticals ; pharmacokinetics ; therapeutic use ; urine ; Radiotherapy Dosage ; Young Adult

Objective: To investigate the effects of high iodine intake on thyroid function in pregnant and lactating women. Methods: A cross sectional epidemiological study was conducted among 130 pregnant women and 220 lactating women aged 19-40 years in areas with high environment iodine level (>300 μg/L) or proper environment iodine level (50-100 μg/L) in Shanxi in 2014. The general information, urine samples and blood samples of the women surveyed and water samples were collected. The water and urine iodine levels were detected with arsenic and cerium catalysis spectrophotometric method, the blood TSH level was detected with electrochemiluminescence immunoassay, and thyroid stimulating hormone (FT(4)), antithyroid peroxidase autoantibody (TPOAb) and anti-thyroglobulin antibodies (TGAb) were detected with chemiluminescence immunoassay. Results: The median urine iodine levels of the four groups were 221.9, 282.5, 814.1 and 818.6 μg/L, respectively. The median serum FT(4) of lactating women in high iodine area and proper iodine area were 12.96 and 13.22 pmol/L, and the median serum TSH was 2.45 and 2.17 mIU/L, respectively. The median serum FT(4) of pregnant women in high iodine area and proper iodine area were 14.66 and 16.16 pmol/L, and the median serum TSH was 2.13 and 1.82 mIU/L, respectively. The serum FT(4) levels were lower and the abnormal rates of serum TSH were higher in lactating women than in pregnant women in both high iodine area and proper iodine area, the difference was statistically significant (FT(4): Z=-6.677, -4.041, P<0.01; TSH: Z=8.797, 8.910, P<0.01). In high iodine area, the abnormal rate of serum FT(4) in lactating women was higher than that in pregnant women, the difference was statistically significant (Z=7.338, P=0.007). The serum FT(4) level of lactating women in high iodine area was lower than that in proper iodine area, the difference was statistically significant (Z=-4.687, P=0.000). In high iodine area, the median serum FT(4) in early pregnancy, mid-pregnancy and late pregnancy was 16.26, 14.22 and 14.80 pmol/L, respectively, and the median serum TSH was 1.74, 1.91 and 2.38 mIU/L, respectively. In high iodine area, the serum FT(4) level in early pregnancy was higher than that in mid-pregnancy and late pregnancy, and the serum TSH level was lower than that in mid-pregnancy and late pregnancy, the difference was statistically significant (FT(4): Z=-2.174, -2.238, P<0.05; TSH: Z=-2.985, -1.978, P<0.05). There were no significant differences in the positive rates of serum thyroid autoantibodies among the four groups of women and women in different periods of pregnancy (P>0.05). The morbidity rates of subclinical hyperthyroidism in pregnant women and lactating women in high iodine area were obviously higher than those in proper iodine areas, the difference was statistically significant (χ(2)=5.363, 5.007, P<0.05). Conclusions: Excessive iodine intake might increase the risk of subclinical hypothyroidism in pregnant women and lactating women. It is suggested to strengthen the iodine nutrition and thyroid function monitoring in women, pregnant women and lactating women in areas with high environmental iodine.
Adult ; China/epidemiology* ; Cross-Sectional Studies ; Female ; Humans ; Hypothyroidism/epidemiology* ; Iodides/administration & dosage* ; Iodine/urine* ; Lactation ; Nutritional Status ; Pregnancy ; Prevalence ; Thyroid Diseases/epidemiology* ; Thyroid Function Tests ; Thyroid Gland/physiology* ; Young Adult

OBJECTIVEWe aimed to evaluate goiter prevalence and iodine nutritional status in areas with high levels of water iodine; to monitor the prevalence of iodine deficiency disorders (IDD) in areas at high risk of IDD; and to compare the prevalence of goiter and urine iodine (UI) concentrations between children living in the two areas.

METHODSBased on surveillance from 2012-2014, we analyzed the concentration of UI and prevalence of goiter in 8-10-year-old children from 12 high-risk IDD provinces, and from 8 provinces and municipalities with excessive water iodine. We calculated goiter prevalence for each UI level according to World Health Organization (WHO) standards and constructed predictive prevalence curves.

RESULTSThe goiter prevalence and median UI of children from areas with high water iodine were not optimal, being above the WHO standards (5% and 100-199 μg/L, respectively), whereas those in high-risk areas fell within the standard. UI and goiter prevalence exhibited a U-shaped relationship in high-risk endemic areas and a parabolic relationship in areas of iodine excess.

CONCLUSIONIodine surplus in high-iodine areas leads to high goiter prevalence and UI. However, in high-risk areas, UI was optimal and goiter prevalence met the national criteria for IDD elimination.

Child ; China ; epidemiology ; Dose-Response Relationship, Drug ; Female ; Goiter ; epidemiology ; Humans ; Iodine ; administration & dosage ; deficiency ; urine ; Male ; Prevalence ; Risk Factors

OBJECTIVEThis study was designed to evaluate the prevalence of thyroid nodules (TNs) and its relationship with urine iodine concentrations (UICs) after the regional rapid economic growth and lifestyle changes.

METHODSA cross-sectional survey was conducted in the general population aged 15-69 years. A questionnaire regarding general and personal characteristics and relevant information was administered. Ultrasonography of the thyroid was performed, and serum triiodothyronine (T3), tetraiodothyronine (T4), serum thyroid stimulating hormone (TSH), free triiodothyronine (FT3), free tetraiodothyronine (FT4), thyroglobulin antibody (TgAb), thyroid peroxidase antibody (TPOAb), and TSH receptor antibody (TRAb) levels were measured for each individual subject.

RESULTSThe prevalence rates of TNs in the whole population, females and males were 27.76%, 34.04%, and 21.60%, respectively. The prevalence of multiple nodules increased with age, whereas the prevalence peaks differed between males and females. The median UICs in the whole population and females with non-TNs were higher than those of subjects with TNs (P=0.0035, P=0.0068). The median UICs in subjects with a single TN were higher than those in subjects with multiple TNs (P=0.0164, P=0.0127). The result showed a U-shaped curve relationship between UIC and prevalence of TNs. The prevalence of TNs was the lowest when the UIC was 140-400 μg/L.

CONCLUSIONThe prevalence of TNs was nearly 30% and increased with age. The relationship between UIC and prevalence of TNs is U-shaped, with an increase in risk when the UIC was <140 μg/L and >400 μg/L. Very low or high UIC levels need attention and correction.

Adolescent ; Adult ; Aged ; China ; epidemiology ; Cross-Sectional Studies ; Female ; Humans ; Iodine ; urine ; Male ; Middle Aged ; Nutritional Status ; Prevalence ; Thyroid Nodule ; chemically induced ; epidemiology ; Young Adult

Child ; China ; Humans ; Iodine ; urine ; Sodium Chloride, Dietary

PURPOSE: The radioiodine ablation therapy is required for patients who underwent a total thyroidectomy. Through a comparative review of a low iodine diet (LID) and a restricted iodine diet (RID), the study aims to suggest guidelines that are suitable for the conditions of Korea. MATERIALS AND METHODS: The study was conducted with 101 patients. With 24-hour urine samples from the patients after a 2-week restricted diet and after a 4-week restricted diet, the amount of iodine in the urine was estimated. The consumed radioiodine amounts for 2 hours and 24 hours were calculated. RESULTS: This study was conducted with 47 LID patients and 54 RID patients. The amounts of iodine in urine, the 2-week case and 4-week case for each group showed no significant differences. The amounts of iodine in urine between the two groups were both included in the range of the criteria for radioiodine ablation therapy. Also, 2 hours and 24 hours radioiodine consumption measured after 4-week restrictive diet did not show statistical differences between two groups. CONCLUSION: A 2-week RID can be considered as a type of radioiodine ablation therapy after patients undergo a total thyroidectomy.
Ablation Techniques ; Adult ; Carcinoma/metabolism/*radiotherapy/surgery ; *Diet ; Female ; Humans ; Iodides/urine ; Iodine/administration & dosage/urine ; Iodine Radioisotopes/metabolism/*therapeutic use ; Male ; Middle Aged ; Republic of Korea ; Thyroid Neoplasms/metabolism/*radiotherapy/surgery ; Thyroidectomy ; Treatment Outcome

OBJECTIVETo investigate the health status of the thyroid and related influencing factors in the seamen in Zhoushan, China.

METHODSA total of 136 coastal seamen (coastal group), 104 deep-sea seamen (deep-sea group), and 272 base staff (base group) who underwent physical examinations in 2014 were selected. Questionnaire survey and ultrasound were performed, and levels of thyroid hormone and urinary iodine were measured.

RESULTSCompared with the coastal group and the base group, the deep-sea group had a significantly higher rate of abnormal ultrasound findings (49.04% vs 30.88%/28.67%, P<0.05), as well as a significantly higher rate of abnormal serum free thyroxine (FT4) (25.00% vs 9.56%/6.25%, P<0.05). The logistic regression analysis showed that in the coastal group, the risk factors for thyroid abnormality on ultrasound were obesity shown by body mass index (BMI) (OR=2.55, 95% CI=1.13~4.13) and annual working time>6 months (OR=4.25, 95% CI=2.02~8.26) (both P<0.05); in the deep-sea group, the risk factors for thyroid abnormality on ultrasound were obesity shown by BMI (OR=3.45, 95% CI=1.28~7.02) and annual working time>6 months (OR=5.33, 95% CI=3.18~9.23) (both P<0.05).

CONCLUSIONThe thyroid abnormality in deep-sea seamen is caused by various reasons and is correlated with annual working time, working environment and area, and iodine nutritional status.

Body Mass Index ; China ; Health Status ; Humans ; Iodine ; urine ; Male ; Naval Medicine ; Occupations ; Risk Factors ; Surveys and Questionnaires ; Thyroid Function Tests ; Thyroid Gland ; diagnostic imaging ; pathology ; Thyroxine ; blood ; Ultrasonography