Iodine status and goiter prevalence after 40 years of salt iodisation in the Kangra District, India

Prevalence of Hypothyroidism in the Population of West Bokaro Coal Mine Area, Jharkhand: A Hospital-Based Observational Study

Background

Hypothyroidism is a common endocrine disorder worldwide. Studies on the prevalence of hypothyroidism in different geographical territories of India are sparse. Data on the prevalence of hypothyroidism in India's coal mine areas are lacking. Therefore, we conducted a cross-sectional study to determine the prevalence of hypothyroidism in the adult population living in the coal mine areas of West Bokaro, Jharkhand, India.

Methods

In total, 1484 individuals of both sexes attending the outpatient department (OPD) of Tata Central Hospital, West Bokaro, Jharkhand, with varied symptoms were screened for thyroid-stimulating hormone (TSH) levels from January 2021 to February 2022. The age of the study participants ranged from 15 to 80 years.

Results

In total, 366 participants had hypothyroidism (subclinical as well as overt). The prevalence of hypothyroidism was greater in women than in men. Among the 366 patients with hypothyroidism, 311 were women and 55 were men, and the ratio was 5.5:1. The percentage of the population having hypothyroidism was 24% in this study, which is higher than that reported in other parts of India; however, our results are similar to those of a study conducted in Assam in 2017. Among patients with high TSH levels, 47%, 25%, and 19% had TSH in the range of 5.6-7.5, 7.6-10.6, and 10.6-20 μU/mL, respectively.

Conclusions

Subclinical and overt hypothyroidism are common in eastern India. Patients with undiagnosed fatigue and weight gain must be screened for TSH levels. Hypothyroidism is no longer a rarity, and coal mine areas are no exception to this phenomenon. A population‑based epidemiological study of thyroid disorders in coal mine areas is an urgent need.

Thyroid Function, Urinary Iodine, and Thyroid Antibody Status Among the Tribal Population of Kashmir Valley: Data From Endemic Zone of a Sub-Himalayan Region

Background: There are scarce data on the prevalence of thyroid disorders and urinary iodine status among tribal populations of India, with no reported data from Kashmir valley.

Objectives: To estimate the prevalence of thyroid disorders and evaluate urinary iodine concentration (UIC) and thyroid autoantibody status among Gujjar and Bakerwal tribes of Kashmir valley.

Methods: This cross-sectional study recruited tribal subjects using multistage cluster sampling from 5 out of 22 districts of Jammu and Kashmir (J&K). Using a predesigned questionnaire, the details of past or current medical history and drug intake, including thyroid hormone medication etc. were recorded after obtaining an informed consent. Examination included anthropometry (height, weight, waist circumference), blood pressure measurement, and relevant general physical examination focusing on goiter palpation, while as laboratory assessment included estimation of serum thyroid hormone levels, antithyroid peroxidase antibody (anti-TPO Ab), and urinary iodine concentration.

Results: A total of 763 subjects (56.4% women and 43.6% men) with a mean(±SD) age of 39.46 (±17.51) ranging from 10 to 85 years and mean(±SD) body mass index (BMI) of 21.28 (±4.16) kg/m² were studied. Goiter was detected in 6.8%, while 33.2% subjects had some form of thyroid dysfunction (including 24.1% subclinical and 6.8% overt hypothyroidism). Subclinical and overt hyperthyroidism were observed in 1.3 and 0.9% of cases, respectively. Anti-TPO Ab was elevated in 13.6%, while the median [interquartile range (IQR)] for UIC was 154.50 (135) μg/L [156.13 (134) μg/L in men and 147.26 (136) μg/L in women]. A negative correlation was observed between UIC and anti-TPO Ab (r = −0.087, P = <0.05).

Conclusion: These novel data on iodine and thyroid status among a tribal population of India generally inhabiting in remote sub-Himalayan belts demonstrate high prevalence of subclinical hypothyroidism (SCH) with persistent iodine deficiency. These preliminary data may warrant large well-designed studies to carry out comprehensive assessment of the problem in this high-risk and marginalized population.

Iodine nutritional status in Himachal Pradesh state, India

INTRODUCTION

Iodine deficiency (ID) is the preventable causes of mental retardation worldwide. Himachal Pradesh (HP) state is a known endemic region to ID.

OBJECTIVE

the objective was to assess the current status of iodine nutrition in a population of HP, India.

METHODOLOGY

There are three regions in HP namely: Kangra, Mandi, and Shimla. In each region, one district was selected namely: Kangra, Kullu, and Solan. In each district, 30 clusters were identified by utilizing population proportional-to-size cluster sampling methodology. A total of 5748 school-age children (SAC) (Kangra; 1864, Kullu; 1986, Solan: 1898), 1711 pregnant mothers (PMs) (Kangra; 647, Kullu; 551, Solan: 513), and 1934 neonates (Kangra; 613, Kullu; 638, Solan: 683), were included in study. Clinical examination of thyroid of each child and PM was conducted. Casual urine samples were collected from children and PMs. Cord blood samples were collected for estimation of thyroid stimulating hormone (TSH) among neonates.

RESULTS

In SAC, total goiter rate (TGR) was 15.8% (Kangra), 23.4% (Kullu), and 15.4% (Solan). Median urinary iodine concentration (UIC) level was 200 μg/l (Kangra), 175 μg/l (Kullu), and 62.5 μg/l (Solan). In PMs, TGR was 42.2% (Kangra), 42.0% (Kullu), and 19.9% (Solan). Median UIC level was 200 μg/l (Kangra), 149 μg/l (Kullu), and 130 μg/l (Solan). In Neonates, TSH levels of > 5 mIU/L were found in 73.4 (Kangra), 79.8 (Kullu), and 63.2 (Solan) percent of neonates.

CONCLUSION

As per, UIC level (<100 μg/l) in SAC, ID was found in district Solan. In Kullu and Solan districts, there were ID (UIC level < 150 μg/l) among PMs. TSH levels indicated ID in all districts surveyed.

Need for neonatal screening program in India: A national priority

In India, out of 342 districts surveyed, 286 have been identified as endemic to iodine deficiency (ID). Research studies conducted in school age children (SAC), Adolescent girls, Pregnant Mothers (PMs) and Neonates have documented poor iodine nutritional status. As observed by total goiter rate of more than 5% and median urinary iodine concentration level of <100 μg/l in SAC and <150 μg/l in PMs as prescribed cutoff of World Health Organization. And higher thyroid stimulating hormone levels among neonates. ID leads to compromised mental development and hence which remain hidden and not visible to family, program managers and administrator. The present review describes the current status of ID in different parts of the country. With a view to strongly recommend the implementation of Neonatal screening program for ID so that the optimal mental development of children can be achieved.

Status of iodine deficiency among pregnant mothers in Himachal Pradesh, India

OBJECTIVE

Iodine is an essential micronutrient needed for the production of thyroid hormones. Pregnant mothers who are deficient in iodine provide less iodine to the fetal thyroid. This results in low production of thyroid hormones by the fetal thyroid, thereby leading to compromised mental and physical development of the fetus. The current study aimed to assess the current status of iodine nutrition among pregnant mothers in Himachal Pradesh, India, a known endemic region for iodine deficiency.

DESIGN

Three districts, namely Kangra, Kullu and Solan, were selected.

SETTING

In each district, thirty clusters (villages) were identified by utilizing the population-proportional-to-size cluster sampling methodology. In each cluster, seventeen pregnant mothers attending the antenatal clinics were included.

SUBJECTS

A total of 1711 pregnant mothers (647 from Kangra, 551 from Kullu and 513 from Solan) were studied. Clinical examination of the thyroid of each pregnant mother was conducted. Spot urine samples were collected from ten pregnant mothers in each cluster. Similarly, salt samples were collected from eleven pregnant mothers in each cluster.

RESULTS

Total goitre rate was 42·2 % (Kangra), 42·0 % (Kullu) and 19·9 % (Solan). The median urinary iodine concentration was 200 μg/l (Kangra), 149 μg/l (Kullu) and 130 μg/l (Solan). The percentage of pregnant mothers consuming adequately iodized salt (iodine content of 15 ppm and more) was found to be 68·3 % (Kangra), 60·3 % (Kullu) and 48·5 % (Solan).

CONCLUSION

Pregnant mothers in Kullu and Solan districts had iodine deficiency as indicated by a median urinary iodine concentration less than 150 μg/l.

Iodine nutrition status amongst neonates in Kangra district, Himachal Pradesh

Iodine deficiency (ID) is an endemic health problem in Kangra district, Himachal Pradesh (HP) state. ID leads to mental retardation, deaf mutism, squint, dwarfism, spastic diplegia, neurological defects and congenital anomalies. Iodine nutrition status amongst neonates can be assessed by estimating thyroid stimulating hormone (TSH). The present study was conducted with an objective to assess the iodine nutrition status amongst Neonates in Kangra district, HP. All of the hospitals in the district which provide obstetric services were enlisted, of which three were selected for this survey. A total of 613 umbilical cord blood samples of neonates were collected on filter paper and analyzed for TSH. WHO (2007) reported that that a <3% frequency of TSH concentrations above 5 mIU/L in samples collected 3-4 days after birth indicates iodine sufficiency in a population. In our study we found that 73.4% of the neonates had TSH levels of more than 5 mlU/l, thus indicating ID in the population studied. Iodine deficiency continues to be a public health problem in Kangra district, Himachal Pradesh.

Prevalence of neonatal hypothyroidism in Kangra Valley, Himachal Pradesh

Iodine deficiency (ID) is an endemic health problem in Kangra District, Himachal Pradesh (HP). ID in pregnant mothers leads to neonatal hypothyroidism (NH), mental retardation, deaf mutism, squint, dwarfism, spastic dysplasia, neurological defects and congenital anomalies. NH can be assessed by estimating the thyroid stimulating hormone (TSH) in cord blood samples. The present study was conducted with an objective to assess the prevalence of NH in district Kangra, HP. In district Kangra, all the hospitals providing obstetric services were enlisted. Three hospitals conducting more than 100 deliveries per year were selected randomly. A total of 613 umbilical cord blood samples of neonates were collected on filter papers and analyzed for TSH. TSH was estimated by enzyme-linked immunosorbent assay method. Neonates with TSH levels ⩾20 mIU/l were recalled for reassessment of TSH for confirmation of NH. Prevalence of NH was found to be 4.4%. This finding suggests the need for the implementation of a neonatal screening program for early detection of children with ID.

Status of iodine deficiency in district Kangra, Himachal Pradesh after 60 years of salt iodization

BACKGROUND/OBJECTIVES

District Kangra, Himachal Pradesh(HP), India is a known endemic area for iodine deficiency disorders (IDD) since 1956. The present study was conducted in district Kangra, Himachal Pradesh with the objective to assess the prevalence of iodine deficiency in school-age children.

SUBJECTS/METHODS

A total of 1864 children in the age group of 6-12 years were included. Clinical examination of thyroid of all children was undertaken. 'On the spot' urine samples were collected from 463 children. The salt samples were collected from 327 children.

RESULTS

The total goiter prevalence of 15.8% was found. The proportion of children with urinary iodine excretion (UIE) levels <50.0, 50.0-99.9 and ≥ 100 μg/l was 2.2, 14.3 and 83.5%, respectively. The median UIE level was 200 μg/l. About 82.3% of the families were consuming salt with iodine content ≥ 15 ppm.

CONCLUSION

The population in district Kangra is possibly in a transition phase from iodine deficient (as revealed by total goiter rate of 15.8%) to iodine sufficiency (as revealed by median UIE levels of 200 μg/l).

Prevalence of hypothyroidism in adults: An epidemiological study in eight cities of India

BACKGROUND

Hypothyroidism is believed to be a common health issue in India, as it is worldwide. However, there is a paucity of data on the prevalence of hypothyroidism in adult population of India.

MATERIALS AND METHODS

A cross-sectional, multi-centre, epidemiological study was conducted in eight major cities (Bangalore, Chennai, Delhi, Goa, Mumbai, Hyderabad, Ahmedabad and Kolkata) of India to study the prevalence of hypothyroidism among adult population. Thyroid abnormalities were diagnosed on the basis of laboratory results (serum FT3, FT4 and Thyroid Stimulating Hormone [TSH]). Patients with history of hypothyroidism and receiving levothyroxine therapy or those with serum free T4 <0.89 ng/dl and TSH >5.50 μU/ml, were categorized as hypothyroid. The prevalence of self reported and undetected hypothyroidism, and anti-thyroid peroxidase (anti-TPO) antibody positivity was assessed.

RESULTS

A total of 5376 adult male or non-pregnant female participants ≥18 years of age were enrolled, of which 5360 (mean age: 46 ± 14.68 years; 53.70% females) were evaluated. The overall prevalence of hypothyroidism was 10.95% (n = 587, 95% CI, 10.11-11.78) of which 7.48% (n = 401) patients self reported the condition, whereas 3.47% (n = 186) were previously undetected. Inland cities showed a higher prevalence of hypothyroidism as compared to coastal cities. A significantly higher (P < 0.05) proportion of females vs. males (15.86% vs 5.02%) and older vs. younger (13.11% vs 7.53%), adults were diagnosed with hypothyroidism. Additionally, 8.02% (n = 430) patients were diagnosed to have subclinical hypothyroidism (normal serum free T4 and TSH >5.50 μIU/ml). Anti - TPO antibodies suggesting autoimmunity were detected in 21.85% (n = 1171) patients.

CONCLUSION

The prevalence of hypothyroidism was high, affecting approximately one in 10 adults in the study population. Female gender and older age were found to have significant association with hypothyroidism. Subclinical hypothyroidism and anti-TPO antibody positivity were the other common observations.

Thyromegaly and iodine nutritional status in a tertiary care hospital in South India

AIM AND OBJECTIVES

1. To assess the iodine nutritional status in patients with goiter by measuring urinary iodine excretion. 2. To compare the iodine nutritional status with the thyroid function and correlate with the type of thyroid disease.

STUDY DESIGN

Case control study.

MATERIALS AND METHODS

Three hundred patients with goiter and one hundred euthyroid healthy non-goitrous volunteers were included in this study.

RESULTS AND CONCLUSIONS

All patients had elevated urinary iodine suggesting excess iodine intake and absence of iodine deficiency. Complications known to be associated with excess iodine, viz., benign goiter (35%), iodine-induced hyperthyroidism or thyrotoxicosis (34%), thyroiditis (16%) and cancer of thyroid (15%) have been observed in this study. Therefore, continued supplementation of edible salt fortified with iodine should be monitored carefully, and supplementation programs should be tailored to the particular region.

Successful efforts toward elimination iodine deficiency disorders in India

Iodine deficiency (ID) is the world's single most important preventable cause of brain damage and mental retardation. Iodine deficiency disorders (IDDs) is a public health problem in 130 countries, affecting 13% of the world population. The simplest solution to prevent the IDD is to consume iodized common salt every day. In India, significant progress has been achieved toward elimination of IDD, in the last 30 years. Satisfactory levels of urinary iodine excretion and iodine content of salt have been documented by the research surveys conducted by research scientists. The results indicate that we are progressing toward elimination of IDD. IDD is due to a nutritional deficiency, which is prima-rily that of iodine, in soil and water. IDD is known to re-appear if the IDD Control Program is not sustained. To ensure that the population continues to have intake of adequate amount of iodine, there is a need of i) periodic surveys to assess the magnitude of the IDD with respect to impact of iodized salt (IS) intervention; ii) strengthening the health and nutrition education activities to create demand for IS and iii) development of a monitoring information system (MIS) for ensuring that the adequately IS is available to the beneficiaries.

Persistence of severe iodine-deficiency disorders despite universal salt iodization in an iodine-deficient area in northern India

Objective

The aim of the present study was to determine the impact of universal salt iodization (USI) on the prevalence of iodine deficiency in the population of an area previously known to have severe iodine deficiency in India.

Design

In a cross-sectional survey, a total of 2860 subjects residing in fifty-three villages of four sub-districts of Gonda District were examined for goitre and urinary iodine concentration. Free thyroxine and thyroid-stimulating hormone levels were also measured. Salt samples from households were collected for estimation of iodine content.

Results

A reduction in goitre prevalence was observed from 69 % reported in 1982 to 27·7 % assessed in 2007. However, 34 % of villages still had very high endemicity of goitre (goitre prevalence >30 %). Twenty-three per cent of households consumed a negligible amount (<5 ppm) and 56 % of households consumed an insufficient amount (5–15 ppm) of iodine from salt.

Conclusions

Although there was an overall improvement in iodine nutrition as revealed by decreased goitre prevalence and increased median urinary iodine levels, there were several pockets of severe deficiency that require a more targeted approach. Poor coverage, the use of unpackaged crystal salt with inadequate iodine and the washing of salt before use by 90 % of rural households are the major causes of persisting iodine-deficiency disorders. This demonstrates lapses in USI implementation, lack of monitoring and the need to identify hot spots. We advocate strengthening the USI programme with a mass education component, the supply of adequately iodized salt and the implementation of complementary strategies for vulnerable groups, particularly neonates and lactating mothers.