Association between iron status and thyroid function in Nepalese children

Autoimmune Thyroid Disorders: The Mediterranean Diet as a Protective Choice

Autoimmune thyroid diseases are on the rise worldwide, and such a rapid increase is mainly driven by environmental factors related to changed lifestyles in "modern" societies. In this context, diet seems to play a crucial role. An unhealthy high-energy diet, rich in animal fat and proteins, salt and refined sugars (the so-called "Western diet") negatively influences the risk of autoimmunity by altering the immune balance and the gut microbiota composition, enhancing oxidative stress and promoting inflammation. In contrast, the Mediterranean diet represents a unique model of healthy eating, characterized by a high intake of food from vegetable sources, a low consumption of saturated fats in favor of unsaturated fats (mainly, olive oil), a moderate consumption of fish (typically, the small oily fishes) and dairy products, as well as a moderate consumption of wine at meals, and a low intake of meat. Thanks to its nutritional components, the Mediterranean Diet positively influences immune system function, gut microbiota composition, and redox homeostasis, exerting anti-oxidants, anti-inflammatory, and immunomodulatory effects. The present review was aimed at exploring the existing knowledge on the correlations between dietary habits and thyroid autoimmunity, to evaluate the role of the Mediterranean diet as a protective model.

The interplay of oxidative stress and immune dysfunction in Hashimoto's thyroiditis and polycystic ovary syndrome: a comprehensive review

In recent years, there has been a significant increase in the concomitant incidence of Hashimoto's thyroiditis (HT) and polycystic ovary syndrome (PCOS), both in terms of incidence, etiology, and clinical consequences. PCOS patients suffering from autoimmune thyroid diseases show insulin resistance, impaired glucose tolerance, weight gain, and metabolic and reproductive complications. Studies have shown that chronic stress and its consequence, i.e. oxidative stress, play an important role in the pathomechanism of both disorders. It has also been shown that long-term exposure to stress triggers biological mechanisms, in particular related to the regulation of the inflammatory cascade, which plays a key role in autoimmune diseases. The paper is a review of the literature on the role of chronic stress, oxidative stress, and immune processes in the pathogenesis of HT and PCOS. In addition, the review is a source of knowledge about the treatment of these diseases, and in particular the use of antioxidants in therapeutic management.

Associations of metal profiles in blood with thyroiditis: a cross-sectional study

Autoimmune thyroiditis (AIT) is increasingly common, and serological markers include thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb). To determine if selected metals influence thyroiditis antibody positivity, this cross-sectional study investigated associations between metals and thyroiditis antibody status. Healthy individuals (n = 1104) completed a questionnaire and underwent checkups of anthropometric parameters, thyroid function status, and levels of seven metals in blood (magnesium, iron, calcium, copper, zinc, manganese, and lead). Associated profiles of glyco- and lipid metabolism were also established. Logistic regression and restricted cubic spline (RCS) regression analysis were applied to adjudge associations between metals and TPOAb and TgAb status. It was found that, after adjusting for likely cofounding factors, participants with antibody positivity had significantly lower serum concentrations of magnesium and iron. When serum magnesium levels were analyzed in quartiles, the odds ratios of quartile 4 were 0.329-fold (95% confidence interval (CI): 0.167-0647) and 0.259-fold (95% CI 0.177-0.574) that of quartile 1 regarding TPOAb and TgAb positivity (P = 0.004, 0.003). After adjustment, the RCS analysis detected nonlinear associations between iron and TPOAb and TgAb positivity (P < 0.01, both). In stratified analyses, these associations regarding magnesium and iron remained for women of reproductive age, but not for postmenopausal women and men. We conclude that lower serum levels of magnesium and iron are associated with incremental positivity of thyroiditis antibodies and may be among the most important metals contributing to AIT in women of reproductive age.

Anemia types in hypothyroid patients in a Coimbatore tertiary care hospital: A prospective observational study

Objective. Hypothyroidism is a syndrome characterized by clinical manifestations associated with thyroid hormone deficiency. The thyroid hormone plays a pivotal role in the hematopoietic system and stimulates precursors of erythropoietin gene expression. Therefore, anemia is a common clinical manifestation in hypothyroid individuals. The goal of this study was to carry out a prospective analysis of the prevalence of anemia, its types, and the etiology behind the differing anemia morphology among hypothyroid patients. Methods. The study was conducted with a sample size of 100 patients suffering from hypothyroidism. The methodology of the study included a questionnaire and consent filling for general information followed by a complete blood test for assessment of blood count, peripheral smear, FT3/FT4 (free triiodothyronine/thyroxine), anemia profile, vitamin B12, folate, LDH (lactate dehydrogenase), reticulocyte count, and thyroid stimulating hormone (TSH). Results. The results of the study are in line with the previous studies and showed severe anemia and prevalence among women of reproductive age. Microcyte hypochromic anemia was found to be the most common type of morphological anemia, which was validated with low hemoglobin (Hb) levels, vitamin B12, FT3, and FT4. Additionally, TSH showed a positive correlation with reticulocyte count, LDH, and Hb in Pearson's correlation test. Conclusion. The study summarizes the need to investigate the underlying etiological agent responsible for better therapy and management of hypothyroidism and anemia suggesting also the use of oral iron supplements along with levothyroxine therapy.

What we know about the relationship between autoimmune thyroid diseases and gut microbiota: a perspective on the role of probiotics on pediatric endocrinology

INTRODUCTION

Autoimmune diseases account for a cumulative overall prevalence of about 3-5% worldwide. Among them, autoimmune thyroid diseases (ATDs) are the most common and comprise two main entities: Hashimoto's thyroiditis (HT) and Graves-Basedow disease (GD). The pathogenesis of ATDs remains not fully elucidated, however the role of microbioma has been proposed. Gut microbiota exert an important influence on the intestinal barrier, nutrient metabolism and immune system development and functions.

EVIDENCE ACQUISITION

In this review, we describe on the main features of ATDs in pediatrics, focusing on the reciprocal influence between gut microbiota, thyroid hormone metabolism and thyroid autoimmunity and consider the role of probiotics and other microbiota-targeted therapies in thyroid diseases with a perspective on pediatric endocrinology.

EVIDENCE SYNTHESIS

Microbiome affects both endogenous and exogenous thyroid hormone metabolism and influences the absorption of minerals important to the thyroid function, which are iodine, selenium, zinc and iron. The alteration of the gut microbiota, with the consequent modifications in the barrier function and the increased gut permeability, seems involved in the development of autoimmune and chronic inflammatory diseases, including ATDs. The supplementation with probiotics showed beneficial effects on the thyroid hormone and thyroid function because this strategy could restore the intestinal eubiosis and the good strain microorganism proliferation.

CONCLUSIONS

Even though the evidence about the interaction between microbiota and ATDs in pediatric patients is limited, the promising results obtained in the adult population, and in other autoimmune disorders affecting children, highlight the need of for further research in the pediatric field.

Thyroidal and Extrathyroidal Requirements for Iodine and Selenium: A Combined Evolutionary and (Patho)Physiological Approach

Iodide is an antioxidant, oxidant and thyroid hormone constituent. Selenoproteins are needed for triiodothyronine synthesis, its deactivation and iodine release. They also protect thyroidal and extrathyroidal tissues from hydrogen peroxide used in the 'peroxidase partner system'. This system produces thyroid hormone and reactive iodine in exocrine glands to kill microbes. Exocrine glands recycle iodine and with high urinary clearance require constant dietary supply, unlike the thyroid. Disbalanced iodine-selenium explains relations between thyroid autoimmune disease (TAD) and cancer of thyroid and exocrine organs, notably stomach, breast, and prostate. Seafood is iodine unconstrained, but selenium constrained. Terrestrial food contains little iodine while selenium ranges from highly deficient to highly toxic. Iodine vs. TAD is U-shaped, but only low selenium relates to TAD. Oxidative stress from low selenium, and infection from disbalanced iodine-selenium, may generate cancer of thyroid and exocrine glands. Traditional Japanese diet resembles our ancient seashore-based diet and relates to aforementioned diseases. Adequate iodine might be in the milligram range but is toxic at low selenium. Optimal selenoprotein-P at 105 µg selenium/day agrees with Japanese intakes. Selenium upper limit may remain at 300-400 µg/day. Seafood combines iodine, selenium and other critical nutrients. It brings us back to the seashore diet that made us what we currently still are.

Reticulocyte Hemoglobin Equivalent: Diagnostic Performance in Assessment of Iron Deficiency in Patients with Hypothyroidism

Introduction

Iron deficiency affects approximately 30% of the world population and is frequently encountered in hypothyroid patients. Early recognition and prompt treatment of iron deficiency in hypothyroid patients lead to a favorable outcome. The aim of this study is to prove the usefulness of reticulocyte hemoglobin equivalent (Ret-He) as a reliable and effective tool in diagnosis of iron deficiency in hypothyroid patients.

Materials and Methods

154 patients with hypothyroidism were included in the study. They were divided into 4 groups. Group 1 included 66 hypothyroid patients without iron deficiency. They were taken as controls. Group 2 included 66 hypothyroid patients with iron deficiency anemia (IDA). Group 3 included 12 hypothyroid patients with iron deficiency but without anemia (ID). Group 4 included 10 hypothyroid patients which had concomitant iron deficiency with anemia of chronic disorder (ACDC). Ret-He was measured by analyzing blood samples on System XN 350. Thyroid profile, serum ferritin, and biochemical data were measured by an automated analyzer. Statistical analysis was performed by using SPSS 23.

Results

Ret-He was significantly lower with (p < 0.001) in group 2 (hypothyroid patients with IDA), group 3 (hypothyroid patients with ID), and in group 4 (hypothyroid patients with ACDC) as compared to controls in group 1 (hypothyroid patients without iron deficiency). After ROC analysis area under the curve (AUC) of Ret-He for hypothyroid patients with IDA was 0.96 at cutoff 28.5 pg with sensitivity of 93% and specificity of 90%. AUC of Ret-He in the hypothyroid group with ACDC was 0.99 at cutoff 30.8 pg with sensitivity of 90% and specificity of 90%. AUC of Ret-He in hypothyroid patients with ID was 0.97 at cutoff 31.7 pg with sensitivity of 91% and specificity of 70%.

Conclusion

Ret-He is a reliable, rapid, and cost-effective tool for diagnosing iron deficiency in hypothyroid patients.

Selected Essential and Toxic Chemical Elements in Hypothyroidism-A Literature Review (2001-2021)

Thyroid hormones are known for controlling metabolism of lipids, carbohydrates, proteins, minerals, and electrolytes and for regulating body temperature. Normal thyroid status depends on the chemical/elemental composition of body fluids and tissues, which changes depending on physiological state, lifestyle and environment. A deficiency or excess of certain essential chemical elements (selenium, zinc, copper, iron or fluorine) or exposure to toxic (cadmium or lead) or potentially toxic elements (manganese or chromium) interacts with thyroid hormone synthesis and may disturb thyroid homeostasis. In our review, accessible databases (Scopus, PubMed and Web of Science) were searched for articles from 2001-2021 on the influence of selected chemical elements on the development of hypothyroidism. Our review adopted some of the strengths of a systematic review. After non-eligible reports were rejected, 29 remaining articles were reviewed. The review found that disruption of the physiological levels of elements in the body adversely affects the functioning of cells and tissues, which can lead to the development of disease.

Correlation of dietary iron intake and serum iron with thyroid stimulating hormone (TSH) and free thyroxine (FT4) levels in adult hyperthyroid patients

OBJECTIVES

National Baseline Health Research 2013 showed that there were 706,757 (0.4%) hyperthyroid patients in Indonesia. Hyperthyroidism is characterized by abnormal thyroid stimulating immunoglobulin (TSI) which causes low TSH and high FT4 levels. Hyperthyroid patients have a decrease of serum iron levels due to acute phase reactions of hyperthyroidism. This study aimed to analyze the correlation between dietary iron intake and serum iron with TSH and FT4 levels in adult hyperthyroid patients.

METHODS

This study was conducted in February-July 2020 at the Clinic of Magelang Health Research and Development Center. Sampling of this cross sectional study was based on inclusion criteria in order to obtain 50 adult hyperthyroid patients. Dietary iron intake was collected with 2 × 24 h dietary recall, serum iron was measured with colorimetric analysis, the levels of TSH and FT4 were measured by ELISA. The collected data were analyzed using Spearman correlation and multivariate linear regression with 95% confidence level.

RESULTS

Deficiencies of dietary iron intake was found in 20 hyperthyroid patients (40%). Low serum iron levels were found in 10 hyperthyroid patients (20%). Spearman correlation analysis showed that dietary iron intake had a negative correlation with TSH (r=-0.294; p<0.05) but did not correlate with FT4 (r=-0.142; p>0.05), while serum iron didn't associated with both TSH (r=0.110; p>0.05) and FT4 (r=0.142; p>0.05). Furthermore, regression analysis showed that dietary iron intake, serum iron, phytate, and thyrozol intake correlate with TSH levels (R square=0.193; p<0.05) and FT4 levels (R square=0.341; p<0.05), but there were no independent association between dietary iron intake and serum iron with TSH and FT4 levels (p>0.05).

CONCLUSIONS

Intake and serum of iron didn't correlate with TSH and FT4 levels in adult hyperthyroid patients.

Mild Anemia May Affect Thyroid Function in Pregnant Chinese Women During the First Trimester

BACKGROUND

Pregnant women are often susceptible to anemia, which can damage the thyroid gland. However, compared with moderate and severe anemia, less attention has been paid to mild anemia. The purpose of this study was to evaluate the effect of mild anemia on the thyroid function in pregnant women during the first trimester.

METHODS

A total of 1,761 women in the first trimester of their pregnancy were enrolled from Shenyang, China, and divided into mild anemia and normal control groups based on their hemoglobin levels. Thyroid-stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) levels were compared between the two groups.

RESULTS

The TSH levels of pregnant women with mild anemia were higher than those of pregnant women without mild anemia (p < 0.05). Normal control women were selected to set new reference intervals for TSH, FT3, and FT4 levels during the first trimester, which were 0.11-4.13 mIU/l, 3.45-5.47 pmol/l, and 7.96-16.54 pmol/l, respectively. The upper limit of TSH 4.13 mU/l is close to the upper limit 4.0 mU/l recommended in the 2017 American Thyroid Association (ATA) guidelines, indicating that exclusion of mild anemia may reduce the difference in reference values from different regions. Mild anemia was related to 4.40 times odds of abnormally TSH levels (95% CI: 2.84, 6.76) and 5.87 increased odds of abnormal FT3 (95% CI: 3.89, 8.85). The proportion of hypothyroidism and subclinical hypothyroidism in patients with mild anemia was higher than that in those without anemia (0.6% vs. 0, p = 0.009; 12.1% vs. 1.9%, p < 0.001). Mild anemia was related to 7.61 times increased odds of subclinical hypothyroidism (95% CI: 4.53, 12.90).

CONCLUSIONS

Mild anemia may affect thyroid function during the first trimester, which highlights the importance of excluding mild anemia confounding when establishing a locally derived specific reference interval for early pregnancy.

Bidirectional Interaction of Thyroid-Kidney Organs in Disease States

Purpose

Thyroid hormones play an important role in growth, development, and physiology of the kidney. The kidney plays a key role in the metabolism, degradation, and excretion of thyroid hormones and its metabolites. The aim of this study is to investigate the prevalence of disease states of thyroid-kidney organs and detecting the correlation between thyroid and kidney function abnormalities.

Materials and Methods

In this retrospective study, a total of forty-five patients with thyroid and kidney dysfunction were investigated. Clinical features, laboratory data at initial presentation, management, and outcomes were collected. The paper has been written based on searching PubMed and Google Scholar to identify potentially relevant articles or abstracts. Median, percentage, mean ± standard deviation (SD), and the two-tailed t-test were used for statistical analyses. The correlation between variables was assessed by Pearson's, Spearman's correlation tests and regression analyses.

Results

The mean ± SD of age of study patients was 48.2 ± 22.93 years (ranging from 1 to 90 years). There was no correlation between serum thyroid-stimulating hormone, free thyroxine levels with estimated glomerular filtration rate, and proteinuria. No association between antimicrosomal antibodies with estimated glomerular filtration rate was seen. Cardiovascular disease was the most common complication of overt hypothyroidism in kidney dysfunction patients.

Conclusion

The present study showed more prevalence of primary hypothyroidism in comparison with other thyroid dysfunctions in patients with kidney dysfunction. Reduced mean values of thyroid function profiles after treatment suggest that this thyroid disease should be considered and ameliorated with thyroid hormone replacement therapy in patients with kidney disease.

Thyroid-Gut-Axis: How Does the Microbiota Influence Thyroid Function?

A healthy gut microbiota not only has beneficial effects on the activity of the immune system, but also on thyroid function. Thyroid and intestinal diseases prevalently coexist-Hashimoto's thyroiditis (HT) and Graves' disease (GD) are the most common autoimmune thyroid diseases (AITD) and often co-occur with Celiac Disease (CD) and Non-celiac wheat sensitivity (NCWS). This can be explained by the damaged intestinal barrier and the following increase of intestinal permeability, allowing antigens to pass more easily and activate the immune system or cross-react with extraintestinal tissues, respectively. Dysbiosis has not only been found in AITDs, but has also been reported in thyroid carcinoma, in which an increased number of carcinogenic and inflammatory bacterial strains were observed. Additionally, the composition of the gut microbiota has an influence on the availability of essential micronutrients for the thyroid gland. Iodine, iron, and copper are crucial for thyroid hormone synthesis, selenium and zinc are needed for converting T4 to T3, and vitamin D assists in regulating the immune response. Those micronutrients are often found to be deficient in AITDs, resulting in malfunctioning of the thyroid. Bariatric surgery can lead to an inadequate absorption of these nutrients and further implicates changes in thyroid stimulating hormone (TSH) and T3 levels. Supplementation of probiotics showed beneficial effects on thyroid hormones and thyroid function in general. A literature research was performed to examine the interplay between gut microbiota and thyroid disorders that should be considered when treating patients suffering from thyroid diseases. Multifactorial therapeutic and preventive management strategies could be established and more specifically adjusted to patients, depending on their gut bacteria composition. Future well-powered human studies are warranted to evaluate the impact of alterations in gut microbiota on thyroid function and diseases.

Thyro-entero-gastric autoimmunity: Pathophysiology and implications for patient management

The association between autoimmune atrophic gastritis and thyroid disorders has been observed since the early 1960s and the expression "thyrogastric syndrome" was coined to indicate the presence of thyroid autoantibodies or autoimmune thyroid disease in patients with pernicious anemia, a late clinical stage of autoimmune atrophic gastritis. More recently, it was confirmed that autoimmune thyroid disorders, in particular Hashimoto's thyroiditis, may be frequently associated with other organ-specific, immune-mediated disorders, such as autoimmune atrophic gastritis or celiac disease. The association of Hashimoto's thyroiditis with autoimmune atrophic gastritis or celiac disease in adult patients is currently considered part of the polyglandular autoimmune syndromes which include several autoimmune disorders associated with an autoaggressive impairment of endocrine glands. From a clinical point of view, the thyro-entero-gastric autoimmunity may lead to potentially serious consequences like anemia, micronutrients deficiencies, and drugs malabsorption, as well as to an increased risk for malignancies. These alterations may frequently present in an underhand manner, with consequent diagnostic and treatment delays. Many aspects of the association between thyroid, gastric and intestinal autoimmune diseases still await clarification. The present review focuses on the embryological, genetic and pathophysiological aspects of thyro-entero-gastric autoimmunity. In particular, the current diagnostic criteria of autoimmune thyroid disease, autoimmune atrophic gastritis, and celiac disease are reviewed, along with the evidences for their association in poly-autoimmunity syndromes. The benefits of proactive screening of autoimmune thyroid disorders in patients with autoimmune gastritis or enteropathy and viceversa are also discussed.

The effect of thyroid hormone deficiency on erythropoiesis in dogs

This research aimed to evaluate the effect of thyroid hormone deficiency on the erythrocytic system in dogs. Dogs with clinical symptoms of hypothyreosis such as obesity, hyperpigmentation, and lethargy were selected. The dogs demonstrating breed predisposition to hypothyreosis were incorporated in the analysis: Dachshunds, Retrievers, and mixed-breed dogs. A detailed history was taken and clinical, hormonal, biochemical and haematological blood tests were performed. Peripheral blood samples were taken from 53 dogs. Finally, the dogs with the initial T4 (thyroxine) concentration < 1.3 µg/dl and animals demonstrating clinical improvement after a 2-month therapy with levothyroxine at a dose of 10 µg/kg administeredper ostwo times a day were qualified. The animals between 10 months to 13 years of age were divided into two groups: clinically healthy (control group, n = 35) and dogs presenting clinical symptoms of hypothyreosis (experimental group, n = 18). In this research, the broadly described normocytic normochromic non-regenerative anaemia was not diagnosed in dogs with hypothyreosis. However, a positive correlation between T4 and red blood cell indices such as the average mass of haemoglobin per red blood cell, concentration of haemoglobin in a given volume of packed red blood cells as well as a negative correlation with haematocrit value was discovered in the experimental group after the 2-month therapy with levothyroxine. These results point to the influence of thyroid hormones on erythropoiesis. This observation is partially consistent with other studies, which noted the casual link between the changes in red blood cell system and the function of thyroid in dogs and humans.

Micronutrients, iodine status and concentrations of thyroid hormones: a systematic review

Context

The metabolism of thyroid hormones, which are essential for normal development, involves many proteins and enzymes. It requires iodine as a key component but is also influenced by several other micronutrients, including selenium, zinc, iron, and vitamin A.

Objective

This systematic review was designed to investigate the effect of micronutrient status and supplementation on iodine status and thyroid hormone concentrations.

Data Sources

Using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines, electronic databases were searched from their inception to April 2016.

Study Selection

Human studies published in English and reporting data on micronutrient status and iodine status and/or thyroid hormone concentrations were included. Studies that examined the effect of micronutrient supplementation on iodine status and/or thyroid hormone concentrations were also included.

Data Extraction

A predesigned and piloted data extraction form was used to compile data from individual studies.

Results

A total of 57 studies were included: 20 intervention studies and 37 observational studies. Although observational evidence suggests that concentrations of selenium, zinc, and iron are positively associated with iodine status, data from randomized controlled trials fail to confirm this relationship.

Conclusions

Further studies are needed to provide greater understanding of the role of micronutrient status in iodine nutrition and thyroid function to ascertain the public health implications for populations worldwide.

Association of antithyroglobulin antibody with iodine nutrition and thyroid dysfunction in Nepalese children

Background

Aberrant iodine intake and thyroid autoimmunity affect thyroid function. Deficiencies of iodine including thyroid disorders have serious impact on child physical and mental development. This study was conducted to investigate iodine nutrition, thyroid function and thyroid autoimmunity in the Nepalese children, and explore the association of thyroidal autoimmunity with iodine nutrition and thyroid dysfunction.

Methods

Five schools from Udayapur district of eastern Nepal were selected for the study. A total of 213 school children aged 6–12 years were enrolled, and anthropometric data, urine samples and blood samples were collected. Urinary iodine concentration (UIC), free triiodothyronine (fT3), free thyroxine (fT4), thyroid stimulating hormone (TSH), and antithyroglobulin antibody (TgAb) was measured. Independent T test, Man-Whitney test, Chi-square test and Fisher’s Exact test were used for testing statistical significance. Spearman’s correlation analysis was done to find association between variables.

Results

The median UIC with IQR, mean ± SD fT3, mean ± SD fT4, median TSH and TgAb with IQR was 150.0 μg/L (102.8; 204.0), 2.49 ± 0.83 pg/ml, 1.33 ± 0.42 ng/dl, 2.49 mIU/L (1.58; 4.29), and 21.40 IU/ml (15.54; 31.20) respectively. Elvated TgAb (≥30 IU/ml, thyroid autoimmune condition) was seen in 25.8% (n = 55) children. UIC was less than 100 μg/L in 17.4% (n = 37) of the children. Subclinical hypothyroidism, overt hypothyroidism and sublinical hyperthyroidism was seen in 1.4% (n = 3), 3.3% (n = 7) and 3.8% (n = 8) children respectively. A strong association of TgAb with UIC (r = − 0.210, p = 0.002) and thyroid hormones; fT3 (r = − 0.160, p = 0.019), fT4 (r = − 0.275, p < 0.001), and TSH (r = 0.296, p < 0.001) was seen. The relative risk for thyroid autoimmunity in children with UIC less than 100 μg/L was 1.784 (95% CI: 1.108–2.871, p = 0.024). Similarly, children with thyroid autoimmunity had higher relative risk [7.469 (95% CI: 2.790–19.995, p < 0.001)] for thyroid dysfunction.

Conclusions

School children of eastern Nepal have adequate iodine nutrition. Thyroid autoimmunity is very common, while thyroid dysfunction is sparse in children. An association of thyroid autoimmunity with iodine nutrition and thyroid dysfunction was seen in children.

Association of exposure to multiple metals with papillary thyroid cancer risk in China

Papillary thyroid cancer (PTC) has inflicted huge threats to the health of mankind. Metal pollution could be a potential risk factor of PTC occurrence, but existing relevant epidemiological researches are limited. The current case-control study was designed to evaluate the relationships between exposure to multiple metals and the risk of PTC. A total of 262 histologically confirmed PTC cases were recruited. Age- and gender-matched controls were enrolled at the same time. Urine samples were used as biomarkers to reflect the levels of environmental exposure to 13 metals. Conditional logistic regression models were adopted to assess the potential association. Single-metal and multi-metal models were separately conducted to evaluate the impacts of single and co-exposure to 13 metals. The increased concentration of urinary Cd, Cu, Fe, and Pb quartiles was found significant correlated with PTC risk. We also found the decreased trends of urinary Se, Zn, and Mn quartiles with the ORs for PTC. These dose-response associations between Pb and PTC were observed in the single-metal model and remained significant in the multi-metal model (OR_25-50th=1.39, OR_50-75th=3.32, OR_>75th=7.62, p for trend <0.001). Our study suggested that PTC was positively associated with urinary levels of Cd, Cu, Fe, Pb, and inversely associated with Se, Zn, and Mn. Targeted public health policies should be made to improve the environment and the recognition of potential risk factors. These findings need additional studies to confirm in other population.

Hepcidin and Iron Homeostasis in Patients with Subacute Thyroiditis and Healthy Subjects

Purpose

Hepcidin is an acute-phase protein involved also in regulation of iron homeostasis. The aim of the study was to prospectively assess for the first time the hepcidin_EL concentration in patients with subacute thyroiditis (SAT), to identify biochemical determinants of hepcidin_EL concentration and evaluate the potential role of hepcidin in SAT diagnosis and monitoring.

Methods

Out of 40 patients with SAT initially recruited, restrictive inclusion criteria fulfilled 21 subjects aged 45 ± 10 years and 21 healthy control subjects (CS). Hepcidin_EL concentration, thyroid status, and iron homeostasis were evaluated at SAT diagnosis and following therapy and compared with CS.

Results

The median hepcidin_EL concentration at SAT diagnosis is higher than that in CS (48.8 (15.9-74.5) ng/mL vs. 18.2 (10.2-23.3) ng/mL, p = 0.009) and is significantly lower after treatment (4.0 (1.2-10.0) ng/mL, p = 0.007) compared with CS. The ROC analysis for hepcidin_EL at SAT diagnosis revealed that area under the curve (AUC) is 0.735 (p = 0.009), and the cut-off for hepcidin_EL concentration is 48.8 ng/mL (sensitivity 0.52 and specificity 0.95). Hepcidin_EL in SAT patients correlated with CRP (r = 0.614, p = 0.003), ferritin (r = 0.815, p < 0.001), and aTPO (r = -0.491, p = 0.024). On multiple regression, the correlation between hepcidin_EL and ferritin was confirmed (p < 0.001).

Conclusions

SAT is accompanied by a significant increase in hepcidin, which reflects an acute-phase inflammatory process. Parameters of iron homeostasis improved significantly while inflammatory indices got lower following recovery. The potential role of hepcidin as a predictive factor of the risk of SAT relapse needs to be assessed in studies on larger groups of SAT patients.

The Unexplored Crossroads of the Female Athlete Triad and Iron Deficiency: A Narrative Review

Despite the severity and prevalence of iron deficiency in exercising women, few published reports have explored how iron deficiency interacts with another prevalent and severe condition in exercising women: the 'female athlete triad.' This review aims to describe how iron deficiency may interact with each component of the female athlete triad, that is, energy status, reproductive function, and bone health. The effects of iron deficiency on energy status are discussed in regards to thyroid function, metabolic fuel availability, eating behaviors, and energy expenditure. The interactions between iron deficiency and reproductive function are explored by discussing the potentially impaired fertility and hyperprolactinemia due to iron deficiency and the alterations in iron metabolism due to menstrual blood loss and estrogen exposure. The interaction of iron deficiency with bone health may occur via dysregulation of the growth hormone/insulin-like growth factor-1 axis, hypoxia, and hypothyroidism. Based on these discussions, several future directions for research are presented.

Anemia among Women Attending Antenatal Care at the University of Gondar Comprehensive Specialized Referral Hospital, Northwest Ethiopia, 2017

BACKGROUND

In Ethiopia, prenatal anemia is a major public health concern affecting both the health of the woman and babies. The World Health Organization recommends to conduct repeated prevalence studies concerning prenatal anemia . However, there is no recent evidence on the magnitude of the prenatal anemia. Therefore, the aim of this study was to determine the prevalence and the associated factors of prenatal anemia among women attending the Antenatal Care Clinic at the University of Gondar Referral Hospital.

METHODS

A facility-based cross-sectional quantitative study was conducted among 362 participants from June 03-July 08, 2017, at the University of Gondar Comprehensive Specialized Hospital, Northwest Ethiopia. The systematic random sampling technique was employed. Structured interviewer administered questionnaire was used. Human Immunodeficiency Virus (HIV) screening was conducted. Nutritional status of the participants was assessed. Blood sample was collected by capillary tube . Intestinal parasite was examined by stool wet mount test. HIV serostatus was detected. Anemia was defined as hemoglobin concentration below 11 g/dl. The multivariable logistic regression model was employed to identify associated factors and to control the possible effects of confounders.

RESULT

The prevalence of anemia was 22.2% (95% CI: 18.11, 27.1%). The highest odds of anemia were observed among pregnant women with family size of >five [AOR = 3 (95% CI: 1.03, 8.65)], unprotected water source users, [AOR = 4.09 (95% CI: 1.75, 9.55)], HIV infected [AOR = 2.94(95% CI: 1.37, 6.35)], and multigravida women [AOR = 3.5 (95% CI: 1.35, 9.17)].

CONCLUSION AND RECOMMENDATIONS

The prevalence of anemia among pregnant women attending the University of Gondar Referral Hospital was a moderate public health problem. Unprotected water source, large family size, Human Immunodeficiency Virus infection, and repeated pregnancies were factors that predicted anemia. Thus, prevention of Human Immunodeficiency Virus infection, family planning utilization, and accessing pure water are recommended.

The Relation Between Thyroid Function and Anemia: A Pooled Analysis of Individual Participant Data

Context

Anemia and thyroid dysfunction often co-occur, and both increase with age. Human data on relationships between thyroid disease and anemia are scarce.

Objective

To investigate the cross-sectional and longitudinal associations between clinical thyroid status and anemia.

Design

Individual participant data meta-analysis.

Setting

Sixteen cohorts participating in the Thyroid Studies Collaboration (n = 42,162).

Main Outcome Measures

Primary outcome measure was anemia (hemoglobin <130 g/L in men and <120 g/L in women).

Results

Cross-sectionally, participants with abnormal thyroid status had an increased risk of having anemia compared with euthyroid participants [overt hypothyroidism, pooled OR 1.84 (95% CI 1.35 to 2.50), subclinical hypothyroidism 1.21 (1.02 to 1.43), subclinical hyperthyroidism 1.27 (1.03 to 1.57), and overt hyperthyroidism 1.69 (1.00 to 2.87)]. Hemoglobin levels were lower in all groups compared with participants with euthyroidism. In the longitudinal analyses (n = 25,466 from 14 cohorts), the pooled hazard ratio for the risk of development of anemia was 1.38 (95% CI 0.86 to 2.20) for overt hypothyroidism, 1.18 (1.00 to 1.38) for subclinical hypothyroidism, 1.15 (0.94 to 1.42) for subclinical hyperthyroidism, and 1.47 (0.91 to 2.38) for overt hyperthyroidism. Sensitivity analyses excluding thyroid medication or high levels of C-reactive protein yielded similar results. No differences in mean annual change in hemoglobin levels were observed between the thyroid hormone status groups.

Conclusion

Higher odds of having anemia were observed in participants with both hypothyroid function and hyperthyroid function. In addition, reduced thyroid function at baseline showed a trend of increased risk of developing anemia during follow-up. It remains to be assessed in a randomized controlled trial whether treatment is effective in reducing anemia.

Iron deficiency is associated with Hypothyroxinemia and Hypotriiodothyroninemia in the Spanish general adult population: Di@bet.es study

Previous studies have suggested that iron deficiency (ID) may impair thyroid hormone metabolism, however replication in wide samples of the general adult population has not been performed. We studied 3846 individuals free of thyroid disease, participants in a national, cross sectional, population based study representative of the Spanish adult population. Thyroid stimulating hormone (TSH), free thyroxin (FT4) and free triiodothyronine (FT3) were analyzed by electrochemiluminescence (E170, Roche Diagnostics). Serum ferritin was analyzed by immunochemiluminescence (Architect I2000, Abbott Laboratories). As ferritin levels decreased (>100, 30–100, 15–30, <15 µg/L) the adjusted mean concentrations of FT4 (p < 0.001) and FT3 (p < 0.001) descended, whereas TSH levels remained unchanged (p = 0.451). In multivariate logistic regression models adjusted for age, sex, UI, BMI and smoking status, subjects with ferritin levels <30 µg/L were more likely to present hypothyroxinemia (FT4 < 12.0 pmol/L p5): OR 1.5 [1.1–2.2] p = 0.024, and hypotriiodothyroninemia (FT3 < 3.9 pmol/L p5): OR 1.8 [1.3–2.6] p = 0.001 than the reference category with ferritin ≥30 µg/L. There was no significant heterogeneity of the results between men, pre-menopausal and post-menopausal women or according to the iodine nutrition status. Our results confirm an association between ID and hypothyroxinemia and hypotriiodothyroninemia in the general adult population without changes in TSH.

Thyroid Disorders in Athletes

When athletic performance begins to deteriorate, it is important to identify possible underlying etiologies to explain such a phenomenon. Causes include inadequate nutrition, improper training habits, infection, and hematologic or endocrine diseases. In athletes, a thorough investigation of potentially reversible underlying medical conditions may be warranted when there are noted disruptions in training, competition, and recovery. Thyroid disorders should be considered in athletes in whom such a condition is suspected. The clinical picture may not be entirely clear, as athletes may have serum laboratory values that do not accurately correlate with the presenting signs and symptoms, as one might expect. That picture is even further muddled in individuals undergoing significant physiologic stress, and in whom anabolic agents or exogenous thyroid hormone are used. Because there are currently no consensus guidelines on the matter, return to play issues must be addressed when implementing treatment strategies and monitoring serial laboratory values on a case-by-case basis.

Chronic anemia and thyroid function

Anaemia is a global public health problem affecting both developing and developed countries with major consequences for human health as well as social and economic development. It occurs at all stages of the life cycle, but is more prevalent in pregnant women and young children. Iron deficiency anaemia (IDA) impairs thyroid metabolism in animals and human and may negatively affect growth and develpment of children. On the other hand both overt and subclinical hypothyroidism are associated with anemia and adding iron to thyroxine therapy improves both conditions compared to thyroxine therapy alone. In addition patients with chronic hemolytic anemia requiring repeated blood transfusion have high prevalence of hypothalamic-pituitary thyroid axis. Both primary hypothyroidism and central hypothyroidism occur in these patients with increasing prevalence with age, severity of the anemia and higher ferritin concentration denoting poor chelation.  Proper blood transfusion and intensive chelation appears to prevent deterioration of thyroid function and in many cases can reverse thyroid pathology. Physicians treating these forms of anemia should be aware of thyroid disorders in these patients for early screening, prevention and proper management of any thyroid dysfunction.

Prevalence of thyroid autoimmunity and dysfunction in women with iron deficiency during early pregnancy: is it altered?

OBJECTIVE

Thyroid disorders and iron deficiency (ID) are associated with obstetrical and fetal complications. Iron is essential for the normal functioning of thyroid peroxidase (TPO-abs) and ID is frequent during pregnancy. The aim of this study was to compare the prevalence of thyroid autoimmunity (TAI) and dysfunction during the first trimester of pregnancy in women with and without ID.

DESIGN

Cross-sectional data analysis of 1900 pregnant women nested within an ongoing prospective collection of pregnant women's data.

METHOD

The study was performed in a single, tertiary referral center. During the first antenatal visit, ferritin, TPO-abs, thyroid-stimulating hormone (TSH) and free T4 (FT4) were measured and age and BMI were recorded. ID was defined as ferritin <15µg/L, TAI when TPO-abs was >60kIU/L, and subclinical hypothyroidism (SCH) when TSH was >2.5mIU/L.

RESULTS

ID was present in 35% of women. Age and BMI were comparable between both groups. In the ID group, the prevalence of TAI and SCH was significantly higher, compared with that in the non-ID group (10% vs 6% and 20% vs 16%; P=0.011 and 0.049 respectively). Ferritin was inversely correlated with serum TSH (ρ=-0.076; P=0.001) and positive with FT4 levels (ρ=0.112; P<0.001). In the logistic regression model, ID remained associated with TAI after correction for confounding factors (P=0.017). The association with SCH was absent after correction for the confounders in the logistic regression model (P=0.082), but remained present in the linear regression model (P=0.035).

CONCLUSIONS

ID was frequent during the first trimester of pregnancy and was associated with a higher prevalence of TAI, higher serum TSH, and lower FT4 levels.