Study on Association between Height, Weight, Iodine Supplementation and Thyroid Volume

The policy of Universal Salt Iodization (USI) could reduce population’s thyroid volume (TVOL) in iodine deficiency areas. Conversely, the improved growth and developmental status of children might increase the TVOL accordingly. Whether the decreased TVOL by USI conceals the increase effect of height and weight on TVOL is unclear. The aim of this study was to analyse the association between height, weight, iodine supplementation and TVOL. Five national Iodine Deficiency Disorder surveys were matched into four pairs according to the purpose of analysis. County-level data of both detected by paired surveys were incorporated, 1: 1 random pairing method was used to match counties or individuals. The difference of TVOL between different height, weight, different iodine supplementation measures groups and the association between TVOL and them were studied. The mean height and weight of children aged 8-10 years increased from 129.9cm and 26.9kg in 2002 to 136.2cm and 32.1kg in 2019; while the median TVOL decreased from 3.10ml to 2.61ml. Iodine supplementation measures can affect TVOL; after exclude iodine effects, the median TVOL was increased with the height and weight. On the other side, after excluding the influence of height and weight, the median TVOL remained decreased. Only age, weight and salt iodine were significant associated with TVOL in multiple linear models. Development of height and weight in children is the evidence of improved nutrition. The decreased TVOL caused by iodized salt measures conceals the increase effect of height and weight on TVOL. Age, weight, and salt iodine affect TVOL significantly.

Prevalence of Iodine Insufficiency Is High Among Pregnant and Lactating Women in Northern Bangladesh Three Decades After Initiating Mandatory Salt Iodization

Objectives Optimum Iodine status during pregnancy and lactation is crucial for normal fetal growth and child development. We assessed the urinary iodine concentration of pregnant and lactating women to determine their iodine status and measured salt iodine from their households. Methods We collected spot urine samples and corresponding household salt samples from 80 pregnant women (37 and 43 second and third-trimester women, respectively) and 49 lactating women (with children <6 months). Urinary iodine was determined by manual digestion with ammonium persulfate followed by Sandell-Kolthoff Reaction using 96 multi-well plates and a micro-plate reader at 405 nm. The iodine content in salt was measured by iodometric titration method. Samples were analyzed at the icddr, b Immunology, Nutrition, and Toxicology Laboratory, Dhaka, Bangladesh. Results The median [IQR] UIC in the second-trimester women, third-trimester women, and lactating women was 90.6[41.9–171.5] mcg/L, 67.9[24.2–144.5] mcg/L, and 74.7[48.1–134.8] mcg/L, respectively. More than three-quarters of pregnant women (73% of the second-trimester women and 79% of the third-trimester women) and more than half of the lactating mothers (57%) were below the WHO recommended cut-offs. Only 42% of the household salts were adequately iodized. A moderate positive linear relationship was found between urinary and household salt iodine content (r = 0.51, P < 0.0001). Conclusions Even with mandatory salt iodization policy in Bangladesh for about three decades, the iodine insufficiency among pregnant and lactating women is widespread and needs to be improved through ensuring the availability of adequately iodized salt or supplement. Funding Sources ETH Zurich, Switzerland.

Assessment of Iodine Nutrition of School Children in Gonda, India, Indicates Improvement and Effectivity of Salt Iodization

Objective: To study the total goiter rate (TGR), urinary iodine concentration (UIC), and salt iodine content among school children in a previously endemic area for severe iodine deficiency disorder (IDD). Design: Cross-sectional epidemiological study. Setting: The study was carried out in the Gonda district (sub-Himalayan region) of North India. Participants: Nine hundred and seventy-seven school children (6-12 years) were studied for parameters such as height, weight, UIC, and salt iodine content. Thyroid volume (TV) was measured by ultrasonography to estimate TGR. Results: The overall TGR in the study population was 2.8% (95% CI: 1.8-3.8%). No significant difference in TGR was observed between boys and girls (3.5% vs. 1.9%, p=0.2). There was a non-significant trend of increasing TGR with age (p=0.05). Median UIC was 157.1 μg/L (IQR: 94.5-244.9). At the time of the study, 97% of salt sample were iodized and nearly 86% of salt samples had iodine content higher than or equal to 15 ppm. Overall, TGR was significantly lower (2.8% vs. 31.0%, p<0.001), and median UIC was significantly higher (157.1 vs. 100.0 μg/L, p<0.05) than reported in the same area in 2009. Conclusions: A marked improvement was seen in overall iodine nutrition in the Gonda district after three and a half decades of USI. To sustainably control IDD, USI and other programs such as health education, must be continuously implemented along with putting mechanisms to monitor the program at regular intervals in place.

Factors associated with the consumption of table salt with inadequate iodine concentrations: a population analysis at a Peruvian household level

Objective: Iodine deficiency is a public health problem, especially in Peru, where it affects women of childbearing age and school-age children. The objective of the study was to conduct a household-level analysis of the factors associated with the consumption of table salt with inadequate amounts of iodine in Peru. Design: Analytical cross-sectional study using Peruvian household-level data from the Demographic and Family Health Survey. Table salt iodine concentrations were considered as the dependent variable (‘inadequate’ with iodine levels <30 PPM and ‘adequate’ with levels ≥30 PPM). The association between iodine concentrations in salt and independent variables was evaluated using crude and adjusted log-binomial regression models. Setting: Peru. Participants: A total of 25 007 households were included. Results: In Peru, 21·8 % households had inadequate table salt iodine concentrations. Belonging to the poorer and poorest wealth index, living in the Highlands natural region, and living with women of childbearing age with native mother tongue were identified as factors associated with inadequate iodine concentrations in table salt. Conclusions: There is an urgent need to ensure that table salt with adequate iodine concentrations is available for poor populations, residents of the Highlands and households with ethnic presence. Likewise, it is necessary to promote good storage practices, greater regulation/law enforcement and better monitoring of the companies that manufacture or sell this product. Furthermore, the population needs to be informed of the disorders associated with iodine deficiency.

Socio-demographic characteristics and Iodine status of the school-going children of Suryodaya Municipality, Ilam

Iodine deficiency disorder (IDD) is a major micronutrient deficiency problem in Nepal. This study was conducted with objective to measure the Urinary iodine excretion (UIE) and attempts were made to relate urinary iodine with salt use and other sociodemographic variables of household of primary school children of Suryodaya municipality of Ilam district of Nepal. A community based cross section study was conducted in two schools of study area selected randomly (lottery method). A total of 202 school children of 6-12 years were recruited for the study to collect urine and salt samples for urine iodine content (UIC) and salt iodine content (SIC) measurement respectively and detail information of study population was achieved from their household. UIC was measured by ammonium persulphate digestion microplate (APDM) method and SIC was estimated by rapid test kit (RTK). Data were expressed in frequency, mean±SD and median (IQR) according to the nature of data. Chi-square test, Mann-Whitney U test and Kruskal-Wallis test were used to test the significance considering p≤0.05 at 95% confidence interval. It was found that Median UIC of the study population was 152.14 µg/L. Overall; it was found that 30.7% children had urine iodine level less than the normal WHO levels. The availability of adequately iodized salt was 93.1% as measured by RTK. There was statically significant association between consumed salt iodine content and urine iodine excretion level (P < 0.05).

A STRATIFIED CROSS-SECTIONAL CLUSTER MODEL SURVEY OF IODINE NUTRITION IN ARMENIA AFTER A DECADE OF UNIVERSAL SALT IODIZATION

Objective: Iodine is a necessary nutrient for the synthesis of thyroid hormones and essential in human development. Being naturally deficient in iodine, Armenia launched a national universal salt iodization (USI) strategy in 2004. Although high rates of goiter continued to be reported, iodine status has not been studied since 2005. Therefore, this study sought to assess the current situation of population iodine nutrition in Armenia.Methods: We used a selective cross-sectional model to recruit three groups: school-age children (SAC), pregnant women (PW), and nonpregnant women of reproductive age (WRA) from each province. We collected casual urine and table salt samples from each participant, which were analyzed for iodine concentration. A repeat urine sample was collected in a subset of participants to adjust the results for within-person variation in iodine concentration. Group-wise urinary iodine concentrations (UICs) were compared with international reference criteria for iodine status.Results: Urine samples were collected from 1,125 participants from 13 different towns in Armenia; a total of 1,078 participants were included in the final analysis: 361 SAC (mean age, 10.5 years, 46.6% female), 356 PW (mean age, 26.1 years), and 361 WRA (mean age, 35.5 years). Population and geographically weighted median UIC were: SAC, 242 μg/L ([25th percentile] 203 to [75th percentile] 289 μg/L); PW, 226 μg/L (209 to 247 μg/L); WRA, 311 μg/L (244 to 371 μg/L). A total of 1,041 table salt samples were sufficient for laboratory analysis: 973 (93.4%) of the salt iodine measurements were within the national standard range of 40 ± 15 mg/kg.Conclusion: The results of household salt sampling indicated a successful USI strategy. While the present study did not achieve a truly representative sample of Armenia's population, the UIC results support the conclusion that iodine deficiency has not recurred and is not an underlying factor for any remaining high goiter prevalence in Armenia.Abbreviations: PW = pregnant women; SAC = school-age children; SI = salt iodine; UIC = urinary iodine concentration; USI = universal salt iodization; WHO = World Health Organization; WRA = women of reproductive age