High national and sub-national coverage of iodised salt in India: evidence from the first National Iodine and Salt Intake Survey (NISI) 2014-2015

National and Sub-National Estimates of Household Coverage of Iodized Salt and Urinary Iodine Status among Women of Reproductive Age in India: Insights from the India Iodine Survey, 2018-19

BACKGROUND

Iodine deficiency is a significant public health problem for many populations worldwide, including India, particularly during the "first 1000 days" of life. Though Universal Salt iodization (USI) is mandatory in India, prior to 2018-19, there was no state-wide survey with estimates of iodine concentrations in salt using iodometric titration. Taking cognizance of this fact, Nutrition International commissioned the first-of-its-kind national-level survey in India, titled the India Iodine Survey 2018-19.

OBJECTIVES

The study was conducted across the country to provide national and subnational estimates of iodine concentrations in household salt using iodometric titration and iodine nutrition status among women of reproductive age (15-49 y).

METHODS

The survey adopted a multi-stage randomcluster probability proportional to size sampling design, covering 21,406 households in all the states and union territories (UTs) of India.

RESULTS

At the national level, the household coverage of edible salt with adequate iodine (content ≥15 parts/million) was 76.3%. At the sub-national level, the coverage varied, with 10 states and 3 UTs achieving USI and 11 states and 2 UTs falling below the national average, with the highest among all the states and UTs, being Jammu and Kashmir and the lowest being Tamil Nadu. At the national level, the median urinary iodine concentration for pregnant women was 173.4 μg/L, for lactating women was 172.8 μg/L, and for non-pregnant, non-lactating women, it was 178.0 μg/L, which is within the adequate iodine nutrition range according to the WHO guidelines.

CONCLUSIONS

The survey results can be widely used by various stakeholders, including government, academia, and industry, to understand the iodine nutrition status of the population, enable the scale-up of sustained efforts toward consolidating gains and achieving USI, leading to the reduction and elimination of Iodine Deficiency Disorders.

Women in Selected Communities of Punjab, India Have a High Prevalence of Iron, Zinc, Vitamin B12, and Folate Deficiencies: Implications for a Multiply-Fortified Salt Intervention

Dietary intake and biomarkers of micronutrient status of 100 non-pregnant women of reproductive age (NPWRA) were assessed to determine optimal levels of iron, zinc, vitamin B12, and folic acid to include in multiply-fortified salt (MFS) that will be evaluated in an upcoming trial. Weighed food records were obtained from participants to measure intake of micronutrients and discretionary salt, and to assess adequacy using Indian Nutrient Reference Values (NRVs). Statistical modeling was used to determine optimal fortification levels to reduce inadequate micronutrient intake while limiting intake above the upper limit. Fasting blood samples were obtained to assess iron, zinc, vitamin B12, and folate status. In usual diets, inadequate intake of iron (46%), zinc (95%), vitamin B12 (83%), and folate (36%) was high. Mean intake of discretionary salt was 4.7 g/day. Prevalence estimates of anemia (37%), iron deficiency (67%), zinc deficiency (34%), vitamin B12 insufficiency (37%), and folate insufficiency (70%) were also high. Simulating the addition of optimized MFS to usual diets resulted in percentage point (pp) reductions in inadequate intake by 29 pp for iron, 76 pp for zinc, 81 pp for vitamin B12, and 36 pp for folate. MFS holds potential to reduce the burden of micronutrient deficiencies in this setting.

Hotspots of un-iodized salt availability among Ethiopian households, evidence from the national survey data

BACKGROUND

Universal salt iodization was started before decades but there are communities using the un-iodized salt till now. More than one-tenth of the Ethiopian community uses un-iodized salt.

OBJECTIVE

This study aimed to identify the hotspots and associate factors of un-iodized salt availability in Ethiopia based on Ethiopian national household survey data.

METHODS

We conducted an in-depth analysis of the Ethiopian Demographic and Health Survey 2016 data. A total of 15,567 households were included in the final analysis. We cleaned and weighed the data using Stata version 16 software and descriptive outputs were reported in graphs and tables. We computed the weighted prevalence of un-iodized salt and prepared it for spatial analysis. Global-level spatial autocorrelation, hotspot analysis using the Getis-Ord Gi* statistics, and spatial interpolation using empirical Bayesian interpolation were executed using ArcGIS 10.3 to predict the magnitude of un-iodized salt at the national level. The binary logistics regression model was used to identify the contributing factors of un-iodized salt utilization. Model goodness of fit was tested with Hosmer and Lemeshow goodness-of-fit test (P = 0.96). Finally, the adjusted odds ratio (AOR) with 95% CI was reported to identify significant factors.

RESULTS

The magnitude of un-iodized salt availability was 14.19% (95% CI: 13.65, 14.75) among Ethiopian households. Un-iodized salt hotspots were found in Afar, Somalia, and Benishangul Gumuz regions. Compared to poorest wealth index: poorer (AOR = 0.55, 95% CI: 0.48, 0.64), middle (AOR = 0.51, 95% CI: 0.44, 0.60), richer (AOR = 0.55, 95% CI: 0.47, 0.64), and richest (AOR = 0.61, 95% CI: 0.50, 0.75); compared to uneducated household head: heads with secondary (AOR = 0.72, 95% CI: 0.60, 0.67) and above secondary (AOR = 0.54, 95% CI: 0.43, 0.67) education reduced the odds of un-iodized salt viability, while households living in highland (AOR = 1.16, 95% CI: 1.05, 1.29) had increased the odds of un-iodized salt availability.

CONCLUSION

More than a tenth of the households in Ethiopia uses un-iodized salt. Hotspots of un-iodized salt availability were found in Somali and Afar regions of Ethiopia. Better wealth index and education of the household heads reduces the odds of un-iodized salt availability while living in a high altitude above 2200 m increases the odds of un-iodized salt availability in Ethiopia.

Probabilistic Health Risk Assessment of Iodine Exposure in Bangladesh

In this study, the concentrations of iodine in household salt samples (n = 690) were determined by following the iodometric titration method, and the health risks of Bangladeshi people were assessed based on the semi-probabilistic approach and the US Environmental Protection Agency (USEPA) deterministic model. After adjusting 20% of cooking losses, the iodine concentration (mean, range) in salt samples of Phultala, Dighalia, Terokhada, Rupsha, Batiaghata, Dumuria, Paikgacha, Koyra, Dacope, and KCC was (29.68 ± 8.67, 14.39-48.26), (31.05 ± 6.68, 15.24-43.18), (26.94 ± 5.57, 16.09-45.72), (24.33 ± 5.61, 12.70-37.26), (26.69 ± 6.73, 10.16-44.87), (27.20 ± 8.44, 9.31-53.34), (27.71 ± 8.09, 8.46-47.42), (28.39 ± 7.80, 11.01-46.57), (28.20 ± 7.97, 3.38-49.10), and (29.21 ± 6.62, 18.62-40.64) mg/kg, respectively. The iodine contents in 97.25% of samples were within the standard fortification level of Bangladesh (15-50 mg/kg), while 2.61% of samples were below this limit. The semi-probabilistic risk assessment studies showed that 80.14% of samples at a low ingestion rate could provide optimal nutrition (150-299 μg/day) to the whole population. Contrarily, at medium, moderate-high, and high consumption rates 34.93%, 65.22%, and 85.94% of samples, respectively, belonged to above the requirements to excessive exposure categories (300-1100 μg/day), which might cause iodine-induced diseases. The target hazard quotient (THQ) values for the adults in most of the samples were within the threshold risk limit (THQ < 1.0), whereas THQ values in 6.82% to 85.97% of samples for the children at low to high ingestion rates, respectively exceeded this limit, which revealed that the adults were almost safe, but the children might face non-carcinogenic health effects. Therefore, regular monitoring of iodine concentration in iodized salts should be done to prevent iodine deficiency or iodine-induced disorders.

Assessment of iodine nutrition of schoolchildren in Gonda, India, indicates improvement and effectivity of salt iodisation

OBJECTIVE

To study the total goitre rate (TGR), urinary iodine concentration (UIC) and salt iodine content among schoolchildren 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 schoolchildren (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 % v. 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 (interquartile range: 94·5-244·9). At the time of the study, 97 % of salt sample were iodised and nearly 86 % of salt samples had iodine content higher than or equal to 15 part per million. Overall, TGR was significantly lower (2·8 % v. 31·0 %, P < 0·001), and median UIC was significantly higher (157·1 v. 100·0 μg/l, P < 0·05) than that 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 Universal Salt Iodisation (USI). To sustainably control IDD, USI and other programmes, such as health education, must be continuously implemented along with putting mechanisms to monitor the programme at regular intervals in place.

Factors Associated with Thyroid Disorders and Iodine Adequacy in Pregnant Saudi Women

Little is known about iodine adequacy and gestational thyroid disorders (GTDs) in Saudi Arabia. This study measured the rates of GTDs and iodine adequacy in 810 healthy Saudi women. Concentrations of serum thyroid hormones and 24-h urine iodine (24-h UIC), and GTDs were diagnosed according to the American Thyroid Association guidelines. Dietary and socioeconomic data to determine factors associated with GTDs and iodine insufficiency were collected. GTDs were detected in 265 women (32.7%) as follows: subclinical (SCH; 20.2%) and overt (OH; 5.8%) hypothyroidism, isolated hypothyroxinemia (ISH; 4.7%) and hyperthyroidism (2%). The SCH (109.2 μg/L; IQR: 77.2-149.7), OH (95.3 μg/L; IQR: 74.3-130.5) and ISH (107.3 μg/L; IQR: 65.5-133.1) groups had median 24-h UIC below the WHO recommended limit, whereas the euthyroid (191.4 μg/L; IQR: 170.03-219.8) and hyperthyroid (159.5 μg/L; IQR: 152.9-238.3) groups were iodine sufficient. Numbers of pregnancies, less education, not consuming iodized salt and not using iodine supplements increased risk of hypothyroidism and ISH. Contrariwise, interval ≥ 3 years from last pregnancy and higher 24-h UIC decreased odds of hypothyroidism and ISH. Moreover, dairy products and egg consumption were markedly lower in all GTD groups. Dairy products and seafood consumption correlated independently with 24-h UIC of the study participants, whereas consuming yogurt, eggs, redfish and shellfish protected against GTDs. In conclusion, GTDs appear to be prevalent in pregnant Saudi women and the hypothyroid and hypothyroxinemia groups had iodine insufficiency. However, consuming iodized salt, iodine supplements, dairy products, seafoods and eggs may protect against GTDs.

Status of salt iodization, related awareness and practice at the household level in slums of Burdwan Municipality, West Bengal

Background:

Monitoring adequacy of salt iodization at consumption level and exploring the reasons for inadequacy, especially in marginalized communities, is crucial to achieve the target coverage of universal salt iodization.

Aims:

To assess the iodine content of salt used at household level, related awareness and practice of respondents and their socio demographic correlates.

Settings and Designs:

This cross-sectional descriptive study was conducted in the slums of Burdwan Municipality in 2019.

Methods and Material:

A total of 330 households were selected by cluster sampling. Salt iodine content was estimated at household level semi-quantitatively by Iodine testing kit, following recommended guidelines. One respondent from each household was interviewed to assess their awareness and practice regarding iodized salt. Kruskal Wallis test, Mann Whitney U test and Multivariable logistic regression was used.

Results:

All 330 households were using iodized salt; 77.6% were consuming adequately iodized and 22.4% were consuming inadequately iodized salts. Only 30.9% of the respondents were aware about the importance of iodized salt, few had correct practice despite inadequate knowledge and none, except one, practiced adding salt at the end of cooking. Awareness and practice were associated with caste and age of the respondents, respectively. Keeping salt container near the oven, adjusting for keeping salt in uncovered container, significantly predicted inadequate level of iodization [AOR 6.17 (95% CI: 2.68-14.26)].

Conclusion:

Inadequate iodization, lack of awareness regarding iodized salt and faulty storing practices amounting to increased risk of inadequate iodization are still prevalent emphasizing the need, in policy, for health education.

Iodine adequacy in reproductive age and pregnant women living in the Western region of Saudi Arabia

BACKGROUND

Despite the serious maternal and foetal complications associated with iodine deficiency during pregnancy, surveys related to pregnant women in the Kingdom of Saudi Arabia (KSA) are lacking. This study, therefore, measured urine iodine concentrations (UIC) alongside the potential socioeconomic factors contributing towards iodine inadequacy in reproductive age and pregnant Saudi women from the Western province of KSA.

METHODS

Spot urine samples were collected from 1222 pregnant and 400 age-matched non-pregnant/non-lactating reproductive age women. The socioeconomic characteristics were obtained through a structured questionnaire. The WHO criteria for iodine sufficiency in non-pregnant (100-199 μg/L) and pregnant (150-249 μg/L) women were applied.

RESULTS

The median UIC in the non-pregnant women (101.64 μg/L; IQR: 69.83-143.55) was at the lowermost WHO recommended cut-off, whereas the pregnant group was iodine deficient (112.99 μg/L; IQR: 81.01-185.57). Moreover, the median UIC was below adequacy across the different trimesters. The use of non-iodised salt significantly increased the risk of iodine deficiency in the non-pregnant (OR = 2.052; 95%CI: 1.118-3.766) and pregnant women (OR = 3.813; 95%CI: 1.992-7.297), whereas taking iodine supplements significantly lowered the risk in both groups (OR = 0.364; 95%CI: 0.172-0.771 and OR = 0.002; 95%CI: 0.001-0.005, respectively). Passive smoking was also an independent risk factor for iodine deficiency in the non-pregnant (OR = 1.818; 95%CI: 1.097-3.014) and pregnant (OR = 1.653; 95%CI: 1.043-2.618) groups. Additionally, BMI correlated independently and significantly with median UIC in the non-pregnant and pregnant populations. However, multiparity (OR = 3.091; 95%CI: 1.707-5.598) and earning below the minimum wage (2.520; 95%CI: 1.038-6.119) significantly increased the risk of iodine deficiency only in the non-pregnant women.

CONCLUSIONS

This study is the first to show borderline iodine sufficiency in reproductive age Saudi women from the Western province, whereas mild iodine deficiency was observed in the pregnant population and could represent a serious public health problem. This study also advocates the necessity to establish routine iodine dietary advice services by the health authorities to foster adequate iodine intake in pregnant women to avoid the perilous consequences of iodine deficiency on maternal-foetal health.

Goiter Prevalence and Thyroid Autoimmunity in School Children of Delhi

INTRODUCTION

Several studies from India, performed prior to 2010, have reported a goiter prevalence of greater than five per cent in school going children. There has been considerable success in universal salt iodization efforts in the past decade. We studied the prevalence of goiter and thyroid autoimmunity in school going children in Delhi between 2010 and 2014 to assess the impact of salt iodization.

MATERIALS AND METHODS

The study employed the population proportionate to size (PPS) cluster sampling methodology to select subjects between the age of six and 14 years, from all 34 wards of 9 districts of Delhi. Cluster randomization sampling design was followed and in this way we identified 30 wards, from each of which 90 children were recruited for the study. The total sample size was 2700 children. Estimation of fT3, fT4, TSH, anti-TPO antibodies and urine iodine concentration (UIC) was done for 10% of the study population.

RESULTS

The prevalence of goiter in this study in the 6-14 years age group was 6.4%. The prevalence of goiter was higher in females (7.7% compared to 5.3% in males, P = 0.01). In the 270 subjects who were selected for biochemical evaluation, subclinical hypothyroidism was seen in 18.4% and positive anti-TPO antibodies were seen in 14.8%. The median UIC was 150 μg/L.

CONCLUSIONS

There is improvement in goiter prevalence in the post-iodization period in Delhi. But still, residual goiter rates are above five per cent suggesting presence of other causes of goiter in this area. There is a high prevalence of thyroid autoimmunity in this population.

Endemic Goiter and Iodine Prophylaxis in Calabria, a Region of Southern Italy: Past and Present

Iodine, a micronutrient that plays a pivotal role in thyroid hormone synthesis, is essential for proper health at all life stages. Indeed, an insufficient iodine intake may determine a thyroid dysfunction also with goiter, or it may be associated to clinical features such as stunted growth and mental retardation, referred as iodine deficiency disorders (IDDs). Iodine deficiency still remains an important public health problem in many countries, including Italy. The effective strategy for the prevention and control of IDDs is universal salt iodization, which was implemented in Italy in 2005 as a nationwide program adopted after the approval of an Italian law. Despite an improvement in the iodine intake, many regions in Italy are still characterized by mild iodine deficiency. In this review, we provide an overview of the historical evolution of the iodine status in the Calabria region, located in the South of Italy, during the past three decades. In particular, we have retraced an itinerary from the first epidemiological surveys at the end of the 1980s to the establishment of the Regional Observatory of Endemic Goiter and Iodine Prophylaxis, which represents an efficient model for the surveillance of IDDs and monitoring the efficacy of iodine prophylaxis.

National Iodine Deficiency Disorders Control Programme: Current status & future strategy

Iodine deficiency disorders (IDDs) constitute a significant public health problem globally. In India, the entire population is prone to IDDs due to deficiency of iodine in the soil of the sub-continent and thus both animal and plant source food grown on the iodine-deficient soil. IDDs encompass the spectrum of disability and disease and include goitre, cretinism, hypothyroidism, abortion, stillbirth, brain damage, learning disabilities, mental retardation, psychomotor defects, hearing and speech impairment. Iodine deficiency is known to be the single largest cause of preventable brain damage. IDDs with their causal association with brain development, cognition, and learning disabilities impair the human resource development and progress of the country. The children born in iodine-deficient regions on an average have 13.5 intelligence quotient (IQ) points lesser than children born in iodine-sufficient regions. IDD control programme in India is a public health success story, with 92 per cent of the population consuming iodized salt. The partnership between government agencies, academic institutions, salt industry, development agencies and civil society has been key to achieve this success story. The sustainable elimination of iodine deficiency in India is within reach, what is required is accelerated and coordinated effort by all key stakeholder at national and State level.