Low serum vitamin D is associated with anti-thyroid peroxidase antibody in autoimmune thyroiditis

Vitamin D levels in non-pregnant women with a history of recurrent pregnancy loss with and without autoantibodies

Background

The objective of this study was to compare the levels of vitamin D in non-pregnant women with a history of recurrent pregnancy loss (RPL) who were seropositive or seronegative for autoantibodies (autoAbs).

Methods

The study examined 58 RPL patients with autoAbs (ANA, anti-TPO, or APAs), 34 RPL patients without autoAbs, and 58 healthy women with prior successful pregnancies and without autoantibodies. The levels of 25 (OH) D were measured using the sandwich ELISA technique.

Results

Our results showed insufficient serum 25(OH) D levels in study groups, with significantly lower levels observed in RPL patients with or without autoAbs compared to healthy women (P=0.0006). In addition, RPL patients with autoAbs had significantly lower 25(OH) D levels compared to RPL patients without autoAbs. We also found that serum levels of 25(OH) D in RPL patients with autoAbs were significantly lower than in RPL patients without autoAbs (20.51 ± 1.15 ng/ml Vs. 23.69 ± 0.74 ng/ml, P=0.0356). Further analysis indicated that RPL patients who were positive for ANA, and APAs, except anti-TPO, had significantly lower than 25(OH)D serum levels than RPL patients without autoAbs.

Conclusion

These findings suggest that RPL patients, especially those with APAs or ANA, have lower vitamin D levels compared to healthy women. This may indicate a link between maternal immune dysregulation due to vitamin D deficiency and the presence of autoantibodies in RPL.

Mapping the path towards novel treatment strategies: a bibliometric analysis of Hashimoto's thyroiditis research from 1990 to 2023

Background

Hashimoto's thyroiditis (HT), a common form of thyroid autoimmunity, is strongly associated with deteriorating clinical status and impaired quality of life. The escalating global prevalence, coupled with the complexity of disease mechanisms, necessitates a comprehensive, bibliometric analysis to elucidate the trajectory, hotspots, and future trends in HT research.

Objective

This study aims to illuminate the development, hotspots, and future directions in HT research through systematic analysis of publications, institutions, authors, journals, references, and keywords. Particular emphasis is placed on novel treatment strategies for HT and its complications, highlighting the potential role of genetic profiling and immunomodulatory therapies.

Methods

We retrieved 8,726 relevant documents from the Web of Science Core Collection database spanning from 1 January 1990 to 7 March 2023. Following the selection of document type, 7,624 articles were included for bibliometric analysis using CiteSpace, VOSviewer, and R software.

Results

The temporal evolution of HT research is categorized into three distinct phases: exploration (1990-1999), rapid development (1999-2000), and steady growth (2000-present). Notably, the United States, China, Italy, and Japan collectively contributed over half (54.77%) of global publications. Among the top 10 research institutions, four were from Italy (4/10), followed by China (2/10) and the United States (2/10). Recent hotspots, such as the roles of gut microbiota, genetic profiling, and nutritional factors in HT management, the diagnostic dilemmas between HT and Grave's disease, as well as the challenges in managing HT complicated by papillary thyroid carcinoma and type 1 diabetes mellitus, are discussed.

Conclusion

Although North America and Europe have a considerable academic impact, institutions from emerging countries like China are demonstrating promising potential in HT research. Future studies are anticipated to delve deeper into the differential diagnosis of HT and Grave's disease, the intricate relationship between gut microbiota and HT pathogenesis, clinical management of HT with papillary thyroid carcinoma or type 1 diabetes, and the beneficial effects of dietary modifications and micronutrients supplementation in HT. Furthermore, the advent of genetic profiling and advanced immunotherapies for managing HT offers promising avenues for future research.

Do Dietary Supplements Affect Inflammation, Oxidative Stress, and Antioxidant Status in Adults with Hypothyroidism or Hashimoto's Disease?-A Systematic Review of Controlled Trials

This systematic review aims to summarise the results of controlled trials on dietary supplements (DS) usage and inflammation, oxidative stress, antioxidant status, and thyroid parameter improvement in hypothyroidism (HT)/Hashimoto's thyroiditis (AIT) patients. The study protocol was registered with PROSPERO (no. CRD42022365149). A comprehensive search of the PubMed, Scopus, and Web of Science databases resulted in the identification of nineteen randomised controlled trials and three non-randomised studies for the review; three studies examined the effect of supplementation with vitamin D, twelve studies-with selenium, and seven studies-with other DS. Based on very limited evidence, the lack of influence of vitamin D supplementation on inflammatory parameters was found, while no studies have examined oxidative stress and antioxidant status parameters, and only one provided results for a single thyroid parameter after an intervention. Some evidence was found proving that selenium supplementation may decrease inflammation and improve thyroid parameters, but reaching a conclusion about its influence on oxidative stress and antioxidant status is not possible because of the insufficient number of studies. Additionally, due to examining other DS (e.g., multicomponent, Nigella sativa, and genistein) only in single studies, conclusions cannot be drawn. Further long-term, high-quality randomised controlled trials are necessary to better understand the influence of DS on inflammation, oxidative stress, and antioxidant status, as well as their potential to improve thyroid gland function in HT/AIT patients.

Assessment of the reporting quality of randomised controlled trials for vitamin D supplementation in autoimmune thyroid disorders based on the CONSORT statement

BACKGROUND-PURPOSE

Randomized controlled trials (RCTs) are the cornerstone of evidence-based medicine, yet their quality is often suboptimal. The Consolidated Standards of Reporting Trials (CONSORT) statement is a list of advice to upgrade the quality of RCTs. The aim of this study was the assessment of the quality of RCTs for vitamin D supplements in thyroid autoimmunity according to the revised CONSORT 2010 checklist.

METHODS

Databases were searched for RCTs involving patients with autoimmune thyroid disorders (AITDs) who received vitamin D supplements published from 2011 to 2021. A list of 37-items was used and adherence ≥75% was considered of optimal quality. The primary outcome was the mean CONSORT adherence of studies. Secondary outcomes were the estimation of compliance per CONSORT item and the examination for possible determinants of the reporting quality.

RESULTS

Thirteen eligible trials were finally included. The mean compliance was 61.15% ± 14.86%. Only threeof the studies (23%) achieved a good reporting quality (≥75%), while ten (77%) were presented with inadequate reporting (<75%). Randomization and blinding were mainly poorly reported. Impact Factor (IF) of journal was associated with the reporting quality in the univariate analysis [p = 0.033, OR = 1.65, 95%CI = (1316, 1773)]. Sample size (p = 0.067), number of authors (p = 0.118) and number of citations (p = 0.125) were marginally not significant. None of the factors showed significant results in multivariate analysis. Reporting quality and IF were strongly positively correlated [Pearson's r = 0.740, p = 0.04].

CONCLUSION

This study shows that mean CONSORT adherence of RCTs for Vitamin D supplementation in AITDs is moderate, reflecting that study quality and transparency could be improved with better adherence to CONSORT rules.

The Role of Vitamin D in Autoimmune Thyroid Diseases: A Narrative Review

Vitamin D (VitD) deficiency has garnered significant attention in contemporary medical research. Although the canonical biological activity of VitD manifests itself mainly in the regulation of calcium-phosphorus metabolism, recent studies show that, thanks to the presence of numerous receptors, VitD may also play an important role in regulating the immune system. VitD deficiency has been demonstrated to impact autoimmune disease, coeliac disease, infections (including respiratory/COVID-19), and patients with cancer. Recent studies also show that VitD plays a significant role in autoimmune thyroid diseases (AITDs). Many studies have shown a correlation between low VitD levels and chronic autoimmune thyroiditis - Hashimoto thyroiditis (HT), Graves' disease (GD), and postpartum thyroiditis (PPT). This review article, therefore, describes the current state of knowledge on the role of VitD in AITDs, including HT, GD, and PTT.

Vitamin D and the Thyroid: A Critical Review of the Current Evidence

Vitamin D is necessary for the normal functioning of many organs, including the thyroid gland. It is, therefore, not surprising that vitamin D deficiency is considered a risk factor for the development of many thyroid disorders, including autoimmune thyroid diseases and thyroid cancer. However, the interaction between vitamin D and thyroid function is still not fully understood. This review discusses studies involving human subjects that (1) compared vitamin D status (primarily determined by serum calcidiol (25-hydroxyvitamin D [25(OH)D]) levels) with thyroid function assessed by thyroid stimulating hormone (TSH), thyroid hormones, and anti-thyroid antibody levels; and (2) evaluated the effect of vitamin D supplementation on thyroid function. Due to the many inconsistencies in the results between the studies, it is still difficult to draw a definite conclusion on how vitamin D status affects thyroid function. Studies in healthy participants observed either a negative correlation or no association between TSH and 25(OH)D levels, while the results for thyroid hormones showed high variability. Many studies have observed a negative association between anti-thyroid antibodies and 25(OH)D levels, but equally many studies have failed to observe such an association. Regarding the studies that examined the effect of vitamin D supplementation on thyroid function, almost all observed a decrease in anti-thyroid antibody levels after vitamin D supplementation. Factors that could contribute to the high variability between the studies are the use of different assays for the measurement of serum 25(OH)D levels and the confounding effects of sex, age, body-mass index, dietary habits, smoking, and the time of year when the samples were collected. In conclusion, additional studies with larger numbers of participants are needed to fully understand the effect of vitamin D on thyroid function.

Polycystic Ovary Syndrome, Subclinical Hypothyroidism, the Cut-Off Value of Thyroid Stimulating Hormone; Is There a Link? Findings of a Population-Based Study

Despite solid evidence regarding the association of over-hypothyroidism with polycystic ovary syndrome (PCOS), the relationship between PCOS and subclinical hypothyroidism (SCH) is still a topic of debate. In the present population-based study, we aimed to assess if there is a difference between PCOS and the control group regarding the upper reference limit of thyroid stimulating hormone (TSH). We also aimed to identify the prevalence of SCH in women with PCOS compared to controls. This study was conducted on data collected in the Iranian PCOS prevalence study and the Khuzestan PCOS prevalence study. Participants that met our eligibility criteria were categorized into two groups: PCOS (n = 207) and control (n = 644). Quantile and logistic regression models were used to explore the effect of PCOS status on TSH cut-off values and SCH, respectively. The 95 percentiles of TSH were not significantly different in the PCOS group compared to control ones (6.12 and 6.56 microU/mL, respectively). There was no statistically significant association between PCOS status and SCH (OR adjusted: 1.40; 95%CI: 0.79, 2.50; p = 0.2). The prevalence of SCH and the upper reference limit of TSH were not significantly different in PCOS and controls. Investigation of SCH in women with PCOS might be questionable.

Correlation Between Vitamin B12 Deficiency and Autoimmune Thyroid Diseases

BACKGROUND

Autoimmune thyroid diseases (AITD) are the most prevalent organ-specific autoimmune disorders. Vitamin B12 plays an important role in the proper functioning of the immune system. The aim of this study was therefore to investigate the correlation between vitamin B12 deficiency and AITD.

MATERIALS AND METHODS

A total of 306 patients (aged 18-65 years, mean - 37.6 ± 11.3 years and comprising 87 males and 219 females) were studied retrospectively (observational study). Patients were divided into groups: with and without vitamin B12 deficiency, and with and without AITD. Differences between groups were evaluated by Fisher's exact test for qualitative variables and by Student's t-test for quantitative variables. Correlations for quantitative factors were determined by the Pearson correlation coefficient and for qualitative factors by Spearman correlation analysis. The sensitivity and specificity of vitamin B12 deficiency for AITD were calculated by ROC analysis.

RESULTS

The vitamin B12 level was significantly lower in patients with AITD (and 200.70 + 108.84) compared to controls (393.41+150.78 p<0.0001). Patients with vitamin B12 deficiency were characterized by significantly higher mean values of anti-TPO (236.60+455.74) compared to controls (39.51+165.57 p<0.0001). Vitamin B12 levels were inversely correlated to anti-TPO levels (r=- 0.233, p<0.001). Roc analysis of vitamin B12 as a diagnostic test for AITD gave the area under curve as 0.881 (95% CI: 0.839-0.924), a sensitivity of - 0.947, a specificity of - 0.768, and a cutoff value of - 178.9.

CONCLUSION

The vitamin B12 level correlates significantly to AITD. The concentration of vitamin B12 should therefore be determined in patients with autoimmune thyroiditis as a diagnostic test with high sensitivity and good specificity.

The correlation between vitamin D and levels of IFN-γ, NF-κB, thyroid antibodies in down syndrome: study in Indonesian children

BACKGROUND AND AIM

Vitamin D (VD) reduces interferon-gamma (IFN-γ) production and prevents nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation, impacting the inhibition of the autoimmunity process such as autoimmune thyroiditis (AITD). Children with Down syndrome (DS) are reported to have a higher risk of autoimmunity and lower VD levels than non-DS. Therefore, this study aimed to evaluate VD levels in Indonesian DS children and their relationship with marker of AITD.

METHODS

This study was conducted on DS children at Dr Soetomo Hospital between February 2021-June 2022. Socio-demographic status, amount of milk, fish and meat consumption, and duration of sun exposure were obtained using a self-report questionnaire. Thyroid hormone (TSH and FT4), thyroid antibody (TPO-Ab and Tg-Ab), 25 (OH)D, IFN-γ, and NF-κB levels were measured using ELISA.

RESULTS

Of the 80 participants, 53.75% had sufficient (50.829±17.713 ng/ml) and 46.25% had non-sufficient (20.606±5.974 ng/ml) VD levels. Daily milk consumption, meat and fish consumption were risk factors contributing to VD levels in multivariate analysis [p=0.003, OR=1.007(1.003-1.012); p=0.004, OR=1.816(1.209- 2.728), respectively]. Participants with sufficient VD had significantly higher TPO-Ab (p=0.007) and Tg-Ab (p=0.016). Mean of VD levels were significantly negatively correlated with IFN-γ levels (r =-0.262, p=0.037) and positively correlated with TPO-Ab (r= 0.432, p=1x10-5,) and Tg-Ab (r= 0.375, p=0.001).

CONCLUSIONS

Majority of subjects had sufficient VD levels. VD suppresses IFN-g, but is unable to affect NF-κB levels, presumably causing high levels of TPO-Ab and Tg-Ab in sufficient VD patient.

Gluten-free diet attenuates the impact of exogenous vitamin D on thyroid autoimmunity in young women with autoimmune thyroiditis: a pilot study

Although both exogenous vitamin D and a gluten-free diet were found to reduce thyroid antibody titers, no study investigated interactions between gluten intake and vitamin D status in patients with autoimmune thyroid disorders. The aim of the present study was to assess whether the gluten-free diet determines the effect of vitamin D treatment on thyroid autoimmunity and thyroid function in young women with autoimmune (Hashimoto's) thyroiditis. The study compared two groups of euthyroid premenopausal women with this disorder, matched for thyroid antibody titers: 31 women with non-celiac gluten sensitivity complying for at least 12 months with the gluten-free diet and 31 unaffected sisters of women with non-celiac gluten sensitivity remaining without any dietary intervention. Plasma titers of thyroid peroxidase and thyroglobulin antibodies, as well as plasma concentrations of thyrotropin, free thyroid hormones, prolactin, 25-hydroxyvitamin D and high-sensitive C-reactive protein were measured at entry and after a six-month follow-up. Moreover, at both time points, the structure parameters of thyroid homeostasis were assessed. Although exogenous vitamin D decreased titers of thyroid peroxidase and thyroglobulin antibodies and increased 25-hydroxyvitamin D levels in each treatment group, this effect was less pronounced in patients on the gluten-free diet than in patients not following any dietary recommendations. Only in the latter group of patients, vitamin D increased SPINA-GT. Treatment-induced changes in thyroid peroxidase and thyroglobulin antibodies correlated with the impact of treatment on 25-hydroxyvitamin D levels. The obtained results suggest that gluten-free diet may impair beneficial effects of exogenous vitamin D in individuals with Hashimoto's thyroiditis.

Mediterranean Diet and Thyroid: An Interesting Alliance

The Mediterranean diet, recognized as being cultural heritage by UNESCO, is mostly plant-based and includes a high consumption of whole-grain, fruit, and vegetables with a moderate consumption of alcohol during meals. Thus, it provides a small amount of saturated fatty acids and a high quantity of antioxidants and fiber. For this reason, it has been considered to have an important role in preventing cardiovascular diseases, chronic kidney diseases, type 2 diabetes mellitus, and cancer, but its relationship with thyroid function and diseases is still under debate. The aim of this review was to search for the possible correlation between the Mediterranean diet and thyroid function, and to critically evaluate the pathophysiological link between selected food intake and thyroid disorders.

The relationship between subclinical hypothyroidism and vitamin D

Aim: Vitamin D (vitD) is primarily responsible for bone formation and mineralization. However, in recent years, it has been suggested that vitD may play a role as an immune modulator in the development of numerous diseases, including autoimmune diseases. It has been observed that there is an association between chronic autoimmune thyroiditis (AIT) and vitD levels. This study aims to investigate whether there are differences in the levels of 25-hydroxy vitamin D [25(OH)D], calcium, and phosphorus in patients with subclinical hypothyroidism (SCH) due to AIT, in patients with antibody-negative subclinical hypothyroidism (ANSCH), and in healthy control subjects. Material and Method: Data from 50 newly diagnosed patients with SCH (35 of whom AIT) and 50 euthyroid and antibody-negative healthy controls who presented to the Department of Endocrinology and Internal Medicine at our hospital between 2018 and 2020 were retrospectively reviewed. Calcium, phosphorus, and 25(OH)D levels of patients and controls were compared. Results: Serum 25(OH)D levels were significantly lower in patients compared to controls (16.2±7.8 ng/ml and 20.4±8.2 ng/ml, respectively; p=0.024). Serum levels of calcium (p=0.081) and phosphorus (p=0.712) did not differ between groups. In a subgroup analysis, patients with AIT had significantly lower 25(OH)D values than controls (p=0.009). Compared to controls, 25(OH)D levels were comparable in the ANSCH group (p=0.096). 25(OH)D level was higher in the AIT group than in the ANSCH group (p=0.01). Conclusion: Our results show that patients with SCH have lower 25(OH)D levels than healthy controls. However, this difference is significant in patients with AIT. It is recommended to screen for vitD deficiency in patients with SCH due to AIT.

The impact of vitamin D on thyroid autoimmunity and hypothalamic-pituitary-thyroid axis activity in myo-inositol-treated and myo-inositol-naïve women with autoimmune thyroiditis: A pilot study

WHAT IS KNOWN AND OBJECTIVE

Vitamin D and myo-inositol reduce thyroid antibody titers in subjects with autoimmune thyroiditis. No previous study has investigated interactions between these agents. The aim of the current study was to determine whether the impact of exogenous vitamin D on thyroid autoimmunity and thyroid function in women with Hashimoto's thyroiditis depends on myo-inositol supplementation.

METHODS

The study population consisted of three thyroid antibody- and insulin sensitivity-matched groups of women with autoimmune thyroiditis and high-normal or slightly elevated TSH levels. Forty-one women (21 in group A and 20 in group C) had been treated for at least 6 months with myo-inositol (group A), while 21 women (group B) had not received myo-inositol preparations. Over the entire study period (6 months), groups A and C continued treatment with myo-inositol (2 g daily), while groups A and B received exogenous vitamin D (4000 IU daily). Plasma titers of thyroid peroxidase and thyroglobulin antibodies, as well as plasma concentrations of glucose, insulin, TSH, free thyroid hormones, prolactin, and 25-hydroxyvitamin D (25-OH-D) were assessed at entry and 6 months later. Moreover, baseline and follow-up values of the structure parameters of thyroid homeostasis were calculated RESULTS AND DISCUSSION: In groups A and B, vitamin D improved insulin sensitivity and increased 25-OH-D levels. Although follow-up antibody titers in both these groups were lower than baseline ones, the impact of vitamin D on thyroid peroxidase and thyroglobulin antibodies was stronger in group A than in group B. Only in group A, vitamin D decreased TSH levels and increased SPINA-GT. There were no differences between baseline and follow-up free values of glucose, thyroid hormones, prolactin, Jostel's index, and SPINA-GD. The impact of vitamin D treatment on antibody titers correlated with treatment-induced changes in 25-OH-D levels and the degree of improvement in insulin sensitivity. In group C, glucose homeostasis markers, antibody titers and hormone levels remained at a similar level throughout the study period.

WHAT IS NEW AND CONCLUSION

The obtained results suggest that the impact of vitamin D on thyroid autoimmunity and hypothalamic-pituitary-thyroid axis activity in subjects with autoimmune thyroiditis is more pronounced if they receive myo-inositol.

Metabolic Characteristics of Hashimoto's Thyroiditis Patients and the Role of Microelements and Diet in the Disease Management-An Overview

Hashimoto’s thyroiditis (HT) is the most common autoimmune disease and the leading cause of hypothyroidism, in which damage to the thyroid gland occurs due to the infiltration of lymphocytes. It is characterized by increased levels of antibodies against thyroid peroxidase and thyroglobulin. In this review, we present the metabolic profile, the effectiveness of micronutrient supplementation and the impact of dietary management in patients with HT. For this current literature review, the databases PubMed, Cochrane, Medline and Embase were reviewed from the last ten years until March 2022. This article provides a comprehensive overview of recent randomized controlled trials, meta-analyses, and clinical trials. Many patients with HT, even in the euthyroid state, have excess body weight, metabolic disorders, and reduced quality of life. Due to frequent concomitant nutritional deficiencies, the role of vitamin D, iodine, selenium, magnesium, iron and vitamin B12 is currently debated. Several studies have underlined the benefits of vitamin D and selenium supplementation. There is still no specific diet recommended for patients with HT, but a protective effect of an anti-inflammatory diet rich in vitamins and minerals and low in animal foods has been suggested. There is insufficient evidence to support a gluten-free diet for all HT patients. Pharmacotherapy, along with appropriate nutrition and supplementation, are important elements of medical care for patients with HT. The abovementioned factors may decrease autoantibody levels, improve thyroid function, slow down the inflammatory process, maintain proper body weight, relieve symptoms, and prevent nutritional deficiencies and the development of metabolic disorders in patients with HT.

Association between serum vitamin D level during pregnancy and recurrent spontaneous abortion: a systematic review and meta-analysis

PROBLEM

Previous studies had shown that there might be an association between serum vitamin D concentrations and the occurrence of recurrent spontaneous abortion (RSA). However, the conclusions remained controversial. The objective of this study was to systematically review the evidence for an epidemiological association between vitamin D and RSA.

METHOD OF STUDY

The literature search was performed in the following databases: PubMed, Web of Science, Embase and Chinese databases. The I² statistic was used to evaluate heterogeneity. Effect sizes were calculated using fixed or random effects models, including standardized mean difference (SMD), odds ratios (OR) and their 95% confidence intervals (95%CI). Then we performed subgroup analysis, sensitivity analysis and publication bias analysis.

RESULTS

Fourteen studies from five countries were included. Based on the results, patients with RSA had lower vitamin D levels than controls (SMD = -1.48, 95%CI: -2.01, -0.94, P<0.001), and pregnant women with vitamin D deficiency (VDD) had a higher risk of developing RSA (OR = 4.02, 95%CI: 2.23, 7.25, P<0.001). There was remarkable heterogeneity between studies (I² _SMD = 97.3%, P<0.001; I² _OR = 82.2%, P<0.001). The results of the subgroup analysis suggested that heterogeneity may be caused by the assay method, age and region. Sensitivity analysis showed the analysis results were robust.

CONCLUSION

Patients with RSA had lower serum vitamin D levels than normal pregnant women, and pregnant women with VDD might be at higher risk for RSA. This article is protected by copyright. All rights reserved.

Association between vitamin D status and subclinical hypothyroidism

Abstract Aims and Objectives: The purpose of this study is to investigate the relation between Vitamin D levels and sub-clinical hypothyroidism and the effect of Vitamin D supplementation on treatment outcome. Design: A retrospective cohort file-based study. Method: In this study, the relation between Vitamin D level and subclinical hypothyroidism and the effect of Vitamin D supplementation on patients with subclinical hypothyroidism were evaluated where 30 patients were diagnosed with subclinical hypothyroidism followed up in Armed forces hospital southern region, KSA was included through electronic files revision. Results: The mean age was 41.6 +/- 12.4 years among the study group. Twenty-seven patients (90%) had their thyroid function test normalized after Vitamin D correction, while the rest had their TSH level improved from the baseline level. The presence of thyroid peroxidase antibodies (TPO) antibodies was found to be inversely related to TSH level after correction of Vitamin D level, and all patients who were negative for TPO 19 (100%) had their Thyroid Stimulating Hormone (TSH) level normalized after Vitamin D correction. In comparison, 3 (27.3%) of TPO-positive patients had subclinical hypothyroidism despite vitamin D correction. Conclusion: Vitamin D deficiency is inversely related to TSH, and TPO status and correction of Vitamin D deficiency in patients with subclinical hypothyroidism can normalize the thyroid function. Further studies are needed to establish the relationship between Vitamin D deficiency and subclinical hypothyroidism.

Biofortification: Effect of Iodine Fortified Food in the Healthy Population, Double-Arm Nutritional Study

It is estimated that one-third of the world's population lives in areas where iodine (I) is scarce and its deficiency is responsible for many related disorders, such as goiter, reproductive failure, hearing loss, growth impairment, congenital I deficiency syndrome, and numerous kinds of brain injury. Mineral deficiencies can be overcome via dietary diversification and mineral supplementation. An alternative or even complementary way is represented by the intake of biofortified foods, which can tackle this lack of micronutrients. In this short-term double-arm nutritional intervention study, a cohort of ten people was supplemented with curly endive leaf biofortified with I and ten people with curly endive without biofortification (Intervention Study on Iodine Biofortification Vegetables (Nutri-I-Food - Full-Text View - ClinicalTrials.gov). The effects on whole-body homeostasis and specifically on I, glucose, lipid, and hepatic, iron metabolism was investigated. Blood samples were obtained at baseline and after 12 days of supplementation with curly endive and compared with controls. Hematochemical and urinary parameters were analyzed at baseline and after 12 days. The results showed that short-term I curly endive intervention did not affect the whole body homeostasis in healthy people and revealed an increase in I concentration in urine samples and an increase in vitamin D, calcium, and potassium concentration in blood samples only in the biofortified cohort respect to controls. This study suggests that short-term consumption of I curly endive crops is safe and could positively impact body health.

Relationship Between Vitamin D and Thyroid: An Enigma

Hypothyroidism is a frequently encountered endocrine disorder in clinical practice. Besides its traditional role in bone health, vitamin D has been shown to have favorable effects in a variety of different systems due to its pleiotropic qualities and ubiquitous receptor expression. Over the years, researchers have been fascinated by the intricate molecular interplay between vitamin D and thyroid. In this regard, attempts have emerged to demonstrate the role of vitamin D in thyroid disorders. This article has reviewed the existing literature on the role of vitamin D in hypothyroidism. We explored studies discussing the physiological interactions between vitamin D and thyroid, as well as the clinical consequences, supplemental and prognostic relevancy of vitamin D in auto-immune thyroid disease (AITD) and hypothyroidism.

Effects of vitamin D treatment on thyroid function and autoimmunity markers in patients with Hashimoto's thyroiditis-A meta-analysis of randomized controlled trials

Introduction

Recent evidence suggested that vitamin D deficiency was associated with Hashimoto's thyroiditis (HT) pathogenesis and thyroid hypofunction. This study aimed to investigate whether vitamin D supplementation would be effective in the prevention and progression of hypothyroidism in patients with HT.

Methods

PubMed, Embase and the Cochrane library were searched for randomized controlled trials (RCTs) and prospective cohort studies published from inception to August 2021.

Results

A total of 7 cohorts of patients from six clinical trials with 258 patients with HT were included. Significant difference was found (WMD = 19.00, 95% CI: 12.43, 25.58, p < 0.001; I² = 90.0%, p_{heterogeneity} < 0.001) between the vitamin D group and control group in serum 25‐hydroxyvitamin D level. And the combined results indicated vitamin D supplementation significantly reduced the level of thyroid peroxidase antibodies (TPO‐Ab) compared to the control group (WMD = −158.18, 95% CI: −301.92, −14.45, p = 0.031; I² = 68.8%, p_{heterogeneity} = 0.007). Whereas no significant differences were found on the levels of thyroid‐stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4) compared to the control group (p > 0.05).

What is New and Conclusion

Our study demonstrated that vitamin D treatment might significantly increase the serum 25(OH)D levels and produce changes in TPO‐Ab titres.

No significant association was found between serum vitamin D treatment and the levels of TG‐Ab, TSH, FT3 and FT4, suggesting that vitamin D is not associated with the function of the thyroid in patients with HT.

Vitamin D and thyroid disorders: a systematic review and Meta-analysis of observational studies

BACKGROUND

The contribution of vitamin D to thyroid disorders has received paramount attention; however, results are mixed. Hence, we designed a systematic review and meta-analysis to obtain a definitive conclusion.

METHODS

The search included PubMed, ISI Web of Science, Scopus, and Google Scholar databases up to March 2021 to collect available papers reporting the relationship between serum levels of vitamin D and thyroid disorders. The pooled effect was reported as weighted mean difference (WMD) and 95% confidence interval (CI).

RESULTS

Out of 6123 datasets, 42 were eligible to get into this systematic review and meta-analysis. Serum vitamin D was markedly lower in autoimmune thyroid diseases (AITD) (WMD - 3.1 ng/dl; 95% CI, - 5.57 to - 0.66; P = 0.013; I² = 99.9%), Hashimoto's thyroiditis (HT) (WMD - 6.05 ng/dl; 95% CI, - 8.35 to - 3.75; P < 0.001; I² = 91.0%) and hypothyroidism patients (WMD - 13.43 ng/dl; 95% CI, - 26.04 to - 0.81; P = 0.03; I² = 99.5%), but not in subjects with Graves' disease (GD) (WMD - 4.14 ng/dl; 95% CI, - 8.46 to 0.17; P = 0.06; I² = 97.5%).

CONCLUSIONS

Our findings suggested lower vitamin D levels in patients with hypothyroidism, AITD, and HT compared to healthy subjects. However, the link between serum vitamin D and GD was only significant among subjects ≥40 years old.

Vitamin D and Hashimoto's Thyroiditis: Observations from CROHT Biobank

The aims of this study were to evaluate: (1) associations of vitamin D with the presence/severity of Hashimoto’s thyroiditis (HT) and (2) correlations of vitamin D with thyroid-related phenotypes. Total 25(OH)D (vitamin D in the text) was measured from stored serum samples of 461 HT patients and 176 controls from a Croatian Biobank of HT patients (CROHT). (1) Vitamin D levels, and proportions of vitamin D deficiency, were compared between HT cases and controls. HT patients were additionally divided into two groups (MILD and OVERT) to take into account HT severity. (2) Correlations between vitamin D and 10 clinical phenotypes in all HT patients and two subgroups of HT patients were tested using the Spearman correlation test. Our analyses were adjusted for age, gender, BMI, smoking status and seasonality of blood sampling. (1) No significant differences in vitamin D levels, or proportions of vitamin D deficiency, were detected between HT patients of all disease stages and controls. However, a nominally significant difference in vitamin D levels between MILD and OVERT subgroups (OR = 1.038, p = 0.023) was observed. Proportions of individuals with vitamin D deficiency during winter–spring were high: all HT cases (64.69%), MILD (60.64%), OVERT (68.7%), controls (60.79%). (2) A nominally significant negative correlation between vitamin D and TSH in all HT patients (r = −0.113, p = 0.029) and a positive correlation between vitamin D and systolic blood pressure in OVERT HT patients (r = 0.205, p = 0.025) were identified. Our study indicates that there is no association between vitamin D and HT; however, there may be a subtle decrease in vitamin D levels associated with overt hypothyroidism.

A novel update on vitamin D in recurrent pregnancy loss (Review)

Recurrent pregnancy loss (RPL) is usually characterized as ≥3 miscarriages before 20 weeks of gestation. Patients with RPL may have autoimmune abnormalities or alloimmune problems. Vitamin D has a major function on the mechanism of immunomodulation at the maternal-fetal interface. However, whether vitamin D can be used as an effective method to treat patients with RPL requires investigation. It has been reported that vitamin D could prevent the occurrence of antiphospholipid syndrome (APS) by reducing the expression levels of anti-β2 glycoprotein and tissue factor in RPL cases with APS. In addition, there is an opposite relationship between vitamin D and thyroid peroxidase antibody levels in autoimmune thyroid disease cases with RPL. Vitamin D changes the ratio of T helper (Th) 1/Th2 and regulatory T cell/Th17 to a certain extent, as well as affects the activity of natural killer cells and the production of cytokines to reduce the incidence of RPL. The objective of the current review was to address the research progress of vitamin D in RPL in recent years, which could facilitate the use of vitamin D treatment to enhance the pregnancy outcome of RPL. Collectively, it was suggested that vitamin D may be used as an important and effective immunotherapeutic agent for patients with RPL.

Relationship of Vitamin D Status with Thyroid Autoimmunity in New Onset Autoimmune Hypothyroidism

Background

Study of serum vitamin D level in new onset hypothyroid patients and its correlation with thyroid related parameters and antibody titers.

Objectives

We aimed to compare serum vitamin D level in new onset hypothyroid patients versus controls. Furthermore we evaluated for any association of vitamin D status with hypothyroid state and its correlation with various thyroid related parameters.

Methodology

In this cross sectional study , 61 new onset hypothyroid subjects (cases) and 40 age, sex and BMI matched healthy individuals (controls) were recruited. Measurements of serum vitamin D, thyroid hormones, thyroid peroxidase antibody (TPO-Ab), parathyroid hormone (PTH), calcium and phosphorus were done for all study participants.

Results

The mean serum vitamin D in cases (22.95±8.59 ng/ml) was significantly lower than the controls (27.9±7.85 ng/ml) (p<0.01). The prevalence of vitamin D deficiency was significantly higher among hypothyroid subjects than controls (p=0.009). Hypothyroid subjects with vitamin D deficiency group had significantly higher TSH level, greater thyroid volume and elevated anti TPO titres than those with vitamin D sufficiency. Serum vitamin D level had significant inverse correlation with anti TPO-Abtiters even after adjustment for age, sex and BMI.

Conclusion

Serum vitamin D is significantly low in new onset hypothyroid patients than healthy controls. Hypothyroid patients with vitamin D deficiency have significantly higher TSH, antibody titres and thyroid volume. A significant negative correlation was observed between serum vitamin D leveland anti TPO titres. Moreover, serum vitamin D remained an independent predictor of TPO level among hypothyroid subjects.

The Importance of Vitamin D Level in Subacute Thyroiditis Disease and the Effect of Vitamin D on Disease Prognosis

OBJECTIVE

Subacute thyroiditis (SAT) is an inflammatory thyroid disease that manifests with severe pain. The presence of the vitamin D receptor in immune system cells shows that vitamin D deficiency can trigger inflammatory diseases. The aim of the present study was to determine the prevalence of vitamin D deficiency in SAT patients, and the relationship between vitamin D level and permanent hypothyroidism and recurrence rate.

METHODS

In this retrospective study, 25-hydroxyvitamin D (25[OH]D) levels of 170 SAT patients and 86 control subjects were compared.

RESULTS

The 25(OH)D levels were significantly lower in the SAT patients, and there was no seasonal difference. A negative correlation was determined between the erythrocyte sedimentation rate and 25(OH)D, but no significant relationship was found between vitamin D level and prognosis.

CONCLUSION

As a result of this study, it was shown that vitamin D levels in subacute thyroiditis patients were significantly lower than in the healthy control group. Although there is no relationship between vitamin D level and disease prognosis, vitamin D deficiency may increase the rate of respiratory tract infections (especially, influenza, coxsackievirus, measles, adenovirus, retroviruses) and eventually SAT development.

Vitamin D and Autoimmune Thyroid Disease-Cause, Consequence, or a Vicious Cycle?

Vitamin D is a steroid hormone traditionally connected to phosphocalcium metabolism. The discovery of pleiotropic expression of its receptor and of the enzymes involved in its metabolism has led to the exploration of the other roles of this vitamin. The influence of vitamin D on autoimmune disease-namely, on autoimmune thyroid disease-has been widely studied. Most of the existing data support a relationship between vitamin D deficiency and a greater tendency for development and/or higher titers of antibodies linked to Hashimoto's thyroiditis, Graves' disease, and/or postpartum thyroiditis. However, there have also been some reports contradicting such relationships, thus making it difficult to establish a unanimous conclusion. Even if the existence of an association between vitamin D and autoimmune thyroid disease is assumed, it is still unclear whether it reflects a pathological mechanism, a causal relationship, or a consequence of the autoimmune process. The relationship between vitamin D's polymorphisms and this group of diseases has also been the subject of study, often with divergent results. This text presents a review of the recent literature on the relationship between vitamin D and autoimmune thyroid disease, providing an analysis of the likely involved mechanisms. Our thesis is that, due to its immunoregulatory role, vitamin D plays a minor role in conjunction with myriad other factors. In some cases, a vicious cycle is generated, thus contributing to the deficiency and aggravating the autoimmune process.

Effect of Vitamin D Supplementation on Thyroid Autoimmunity among Subjects of Autoimmune Thyroid Disease in a Coastal Province of India: A Randomized Open-label Trial

OBJECTIVE

Hashimoto's thyroiditis (HT) is a variant of autoimmune thyroid disorders (AITD) which has been associated with vitamin D (vit-D) deficiency. However, whether vit-D supplementation is linked to reduction of thyroid autoantibodies and improvement of thyroid function is not well characterized. The present study was planned to evaluate the effect of vit-D supplementation on possible improvement of thyroid autoantibody titer and thyroid hormone profile in patients with AITD subjects.

METHODS

Twenty-three patients of HT were given weekly supplementation of 60,000 IU vit-D for 8 weeks followed by once a month for another 4 months. After 6 months of vit-D supplementation, thyroid autoantibody titer (TPO antibody) and thyroid hormone profile was rechecked.

RESULTS

Mean serum vit-D was increased significantly from 15.33 ± 5.71 to 41.22 ± 12.24 ng/mL (normal levels) after supplementation. There was significant increase in thyroid autoantibody titre (from 746.8 ± 332.2 to 954.1 ±4 59.8 IU/ml; P = 0.006) and TSH level (7.23 ± 3.16 to 3.04 ± 2.62 (mIU/L); P = 0.01) following 6 months of vit-D supplementation.

CONCLUSION

Vitamin-D levels were low in AITD patients in eastern India and, its supplementation in HT patients increased thyroid antibody titer and there was significant reduction in serum TSH and increased in free T4.

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.

Immunomodulatory Effects of Vitamin D in Thyroid Diseases

Vitamin D is a secosteroid with a pleiotropic role in multiple physiological processes. Besides the well-known activity on bone homeostasis, recent studies suggested a peculiar role of vitamin D in different non-skeletal pathways, including a key role in the modulation of immune responses. Recent evidences demonstrated that vitamin D acts on innate and adaptative immunity and seems to exert an immunomodulating action on autoimmune diseases and cancers. Several studies demonstrated a relationship between vitamin D deficiency, autoimmune thyroid disorders, and thyroid cancer. This review aims to summarize the evidences on the immunomodulatory effect of vitamin D on thyroid diseases.

Immunomodulatory effect of vitamin D and its potential role in the prevention and treatment of thyroid autoimmunity: a narrative review

The main role of vitamin D is to control mineral homeostasis. However, recent studies suggested the existence of a number of extraskeletal effects. Among the latter, preclinical studies provided consistent data on the involvement of vitamin D in innate and adaptive immunity and autoimmunity. Molecular biology studies showed that both vitamin D receptor and vitamin D enzymatic complexes are expressed in a large number of cells and tissues unrelated to mineral homeostasis. In contrast, only a few randomized clinical trials in humans investigated the possible role of vitamin D in the prevention or treatment of immunological disorders. In this regard, low serum vitamin D levels have been reported in observational trials in human autoimmune disorders. The aim of the present paper was to review the potential implications of vitamin D in immune modulation, with special focus on thyroid autoimmune disorders.

Pathophysiological Role and Therapeutic Implications of Vitamin D in Autoimmunity: Focus on Chronic Autoimmune Diseases

Vitamin D is a pleiotropic secosteroid yielding multiple actions in human physiology. Besides the canonical regulatory activity on bone metabolism, several non-classical actions have been described and the ability of vitamin D to partake in the regulation of the immune system is particularly interesting, though far stronger and convincing evidence has been collected in in vitro as compared to in vivo studies. Whether vitamin D is able to regulate at physiological concentrations the human immune system remains unproven to date. Consequently, it is not established if vitamin D status is a factor involved in the pathogenesis of immune-mediated diseases and if cholecalciferol supplementation acts as an adjuvant for autoimmune diseases. The development of autoimmunity is a heterogeneous process, which may involve different organs and systems with a wide range of clinical implications. In the present paper, we reviewed the current evidences regarding vitamin D role in the pathogenesis and management of different autoimmune diseases.

The Relationship Between Thyroid Antibodies and Vitamin D Level in Primary Hypothyroidism

Introduction:

Vitamin D deficiency is a global health problem. Its deficiency has been reported to be associated with different autoimmune diseases.

Aim:

The aim of this study was to evaluate the relationship between vitamin D level and thyroid antibodies in autoimmune hypothyroidism.

Methods:

A total number of 150 individuals were enrolled in this study. They were divided into the fallowing groups: group I included 50 patients with autoimmune thyroid disease (AITD), group II included 50 patients without autoimmune thyroid disease. Group III included 50 apparently healthy participants representing a control group. All participants underwent a detailed clinical examination and laboratory tests including, 25 (OH) vitamin D, thyroid-stimulating hormone (TSH) and thyroid autoantibodies assessment, including anti-thyroid peroxidase antibodies (anti-TPO) and anti-thyroglobulin antibodies (anti-TG).

Results:

Serum levels of 25 (OH) vitamin D recorded a highly significant difference between the studies groups (20,76±6,31 ng/ml in group I vs. 24,37±9,05ng/ml in group II vs. 24,57±6,45ng/ml in group III, p<0,01). Moreover, there was a highly significant difference between patients with AITD and patients without AITD (20,76±6,31ng/ml vs. 24,37±9,05ng/ml, respectively; p<0,01). The concentration of anti-TPO and anti-TG antibodies were statistically significant higher in patients with vitamin D deficiency (p< 0,001). Serum TSH were significantly higher in group I (p< 0,001).

Conclusion:

Significantly low levels of vitamin D were documented in patients with AITD that were related to the presence of anti-thyroid antibodies and higher level thyroid-stimulation hormone (TSH), suggesting the involvement of vitamin D in the pathogenesis of AITD and the advisability of supplementation.

Vitamin B12 and Vitamin D Levels in Patients with Autoimmune Hypothyroidism and Their Correlation with Anti-Thyroid Peroxidase Antibodies

BACKGROUND

This study was designed to investigate the vitamin D (vit-D) and vitamin B12 (vit-B12) levels and their correlation with anti-thyroid peroxidase (anti-TPO) antibodies in patients with autoimmune hypothyroidism.

METHODS

A total of 130 patients diagnosed with autoimmune hypothyroidism were included in the study retrospectively. The patients were divided into two groups as those having vit-B12 levels below 200 pg/mL (n = 60) and vit-B12 levels equal to or above 200 pg/mL (n = 70). These two groups were compared in terms of age, sex, thyroid-stimulating hormone (TSH), free-T4 (FT4), vit-D, and anti-TPO. The correlation between vit-B12 and anti-TPO levels was also investigated in these groups. Patients were then divided into four groups according to their vit-D levels. Patients with normal vit-D levels (25[OH]D >30 ng/mL; n = 5), those with vit-D insufficiency (20-30 mg/mL; n = 9), those with vit-D deficiency (10-20 ng/mL; n = 43), and those with severe vit-D deficiency (<10 ng/mL; n = 73). These four groups were compared in terms of age, gender, TSH, FT4, vit-B12, and anti-TPO levels. In addition, the correlation between levels of vit-D and anti-TPO was also investigated.

RESULTS

We found that vit-B12 deficiency and vit-D deficiency were associated with autoimmune hypothyroidism, and that there was a negative correlation between vit-B12 and vit-D levels and anti-TPO antibodies in these patients.

CONCLUSION

In patients with autoimmune hypothyroidism, vit-D and vit-B12 deficiency should be investigated at the time of diagnosis and periodically on follow-ups.

Vitamin D Status and Thyroid Autoantibodies in Autoimmune Thyroiditis

A lack of vitamin D seems to be related to autoimmune diseases including autoimmune thyroiditis (AIT). This study intends to determine the correlation between improvement of 25-hydroxyvitamin D [25(OH)D] levels and AIT in patients from an outpatient endocrine clinic in Frankfurt, Germany. This study included 933 patients with thyroid peroxidase antibodies (anti-TPO-Ab) ≥34 kIU/l, including most patients with clear AIT due to a concurrent sonographic evidence of reduced echogenicity. We performed clinical evaluation and laboratory analysis at five points in time within two years retrospectively. Due to a high dropout rate within the observation period, we excluded the last two time points from analysis. Data from 933 AIT patients revealed 89% having vitamin D deficiency or insufficiency [25(OH)D <75 nmol/l] with a median 25(OH)D level of 39.7 nmol/l. At baseline, a weak inverse correlation between 25(OH)D and anti-TPO-Ab was observed during winter (r_s=-0.09, p=0.048*), but not during summer time (p>0.2). We discovered 58 patients having initially a 25(OH)D level < 75 nmol/l (median: 40.2 nmol/l), which improved over time to a 25(OH)D level ≥ 75 nmol/l (median: 83.2 nmol/l, p<0.0005***). Simultaneously, the median anti-TPO-Ab level showed a significant decrease of 25% from 245.8 to 181.3 kIU/l (p=0.036*). A significant reduction of the median anti-TPO-Ab level of 9% was also observed in the control group, which consisted of patients having constantly a 25(OH)D level <75 nmol/l. The result may suggest that in particular patients with 25(OH)D levels < 75 nmol/l benefit from an increase of 25(OH)D levels ≥ 75 nmol/l. Further prospective randomized controlled clinical trials are needed to finally evaluate if vitamin D has immunmodulatory effects in AIT.

Towards a comprehensive etiopathogenetic and pathophysiological theory of multiple sclerosis

Background: Multiple sclerosis (MS) is a neurodegenerative disease caused by dysfunction of the immune system that affects the central nervous system (CNS). It is characterized by demyelination, chronic inflammation, neuronal and oligodendrocyte loss and reactive astrogliosis. It can result in physical disability and acute neurological and cognitive problems. Despite the gains in knowledge of immunology, cell biology, and genetics in the last five decades, the ultimate etiology or specific elements that trigger MS remain unknown. The objective of this review is to propose a theoretical basis for MS etiopathogenesis.Methods: Search was done by accessing PubMed/Medline, EBSCO, and PsycINFO databases. The search string used was "(multiple sclerosis* OR EAE) AND (pathophysiology* OR etiopathogenesis)". The electronic databases were searched for titles or abstracts containing these terms in all published articles between January 1, 1960, and June 30, 2019. The search was filtered down to 362 articles which were included in this review.Results: A framework to better understand the etiopathogenesis and pathophysiology of MS can be derived from four essential factors; mitochondria dysfunction (MtD) & oxidative stress (OS), vitamin D (VD), sex hormones and thyroid hormones. These factors play a direct role in MS etiopathogenesis and have a modulatory effect on many other factors involved in the disease.Conclusions: For better MS prevention and treatment outcomes, efforts should be geared towards treating thyroid problems, sex hormone alterations, VD deficiency, sleep problems and melatonin alterations. MS patients should be encouraged to engage in activities that boost total antioxidant capacity (TAC) including diet and regular exercise and discouraged from activities that promote OS including smoking and alcohol consumption.

The effect of vitamin D on thyroid autoimmunity in euthyroid men with autoimmune thyroiditis and testosterone deficiency

BACKGROUND

Autoimmune (Hashimoto's thyroiditis) is characterized by a strong female preponderance, which may suggest that sex hormones have an impact on thyroid autoimmunity. The aim of this study was to investigate whether testosterone determines vitamin D action on thyroid antibody titers and thyroid function tests in men with autoimmune thyroiditis and low testosterone levels.

METHODS

The study included 36 men with testosterone deficiency, 17 of whom had been treated for at least 26 weeks with oral testosterone undecanoate (120 mg daily). Because of coexistent euthyroid Hashimoto's thyroiditis, all participants were then treated with vitamin D (100 μg daily). Serum titers of thyroid peroxidase and thyroglobulin antibodies, serum levels of thyrotropin, free thyroid hormones, testosterone and 25-hydroxyvitamin D, as well as Jostel's thyrotropin index, SPINA-GT and SPINA-GD were assessed before vitamin D treatment and 26 weeks later.

RESULTS

With the exception of testosterone levels, there were no significant differences between both study groups in serum hormone levels, antibody titers and thyroid function tests. All participants completed the study. In addition to increasing 25-hydroxyvitamin D levels, vitamin D increased SPINA-GT and reduced thyroid peroxidase and thyroglobulin antibody titers. In testosterone-treated men, vitamin D increased testosterone levels. Vitamin D did not affect serum levels of thyrotropin, free thyroid hormones, Jostel's thyrotropin index and SPINA-GD. Treatment-induced changes in thyroid antibody titers and SPINA-GT were more pronounced in testosterone-treated than testosterone-naïve men.

CONCLUSIONS

The obtained results suggest that the beneficial effect on thyroid autoimmunity and thyroid secretory function is stronger in men receiving testosterone therapy.

Vitamin D, Thyroid Autoimmunity and Cancer: An Interplay of Different Factors

BACKGROUND AND AIMS

In spite of large volume of data linking Vitamin D with cardiovascular morbidity, autoimmunity, cancer, and virtually every organ system, Vitamin D and thyroid is a lesser-known aspect of Vitamin D in clinical practice. This article intends to highlight the current literature on the impact of Vitamin D status and supplementation on thyroid autoimmunity and cancer.

METHODS

References for this review were identified through searches of PubMed for articles published to from 1950 to August 2019 using the terms "thyroid" [MeSH Terms] AND "Vitamin D" [MeSH Terms] OR "thyroid" [All Fields] AND "Vitamin D" [All Fields].

RESULTS

Significant inverse correlation was documented between anti-thyroid peroxidase antibody (TPOAb) and serum 25-hydroxy-Vitamin D (25OHD). TPOAb positivity is more prevalent in Vitamin D deficient individuals. A large volume of medical literature is available from observational studies linking Vitamin D with thyroid autoimmunity. Data from interventional studies documenting beneficial effects of Vitamin D on thyroid autoimmunity is also available, but lesser than that from observational studies. Short-term high dose oral Vitamin D supplementation reduces TPOAb titers. Certain Vitamin D receptor (VDR) gene polymorphism have been linked to increased occurrence of autoimmune thyroid disorders (AITD). Vitamin D deficiency, decreased circulating calcitriol has been linked to increased thyroid cancer. Certain VDR gene polymorphisms have been linked with increased as well as decreased occurrence of thyroid cancer. Data is scant on use of Vitamin D and its analogues for treating thyroid cancer.

CONCLUSION

In spite of large volume of medical literature from observational studies linking Vitamin D with thyroid autoimmunity and cancer, meaningful concrete clinical data on impact of Vitamin D supplementation on hard clinical end points in these disorders is lacking, and should be the primary area of research in the next decade.

Positive effect of low dose vitamin D supplementation on growth of fetal bones: A randomized prospective study

The effect of vitamin D supplementation on growth of fetal bones during pregnancy is unclear. The aim of this study was to assess the effect of low dose vitamin D supplementation during pregnancy on bony anthropometric aspects of the fetus. In this prospective randomized trial, 140 patients were divided into two equally matched groups according to age, 25(OH)D level, exercise, and dietary intake. Then 1000 IU per day vitamin D supplement was given to the intervention group while the control group received placebo. Then crown-rump length (CRL) and femur length (FL) during the first trimester and humerus and femur lengths as well as their proximal metaphyseal diameter (PMD), midshaft diameter (MSD) and distal metaphyseal diameter (DMD) in the second and third trimester were measured using ultrasonography technique. Finally, no significant difference was observed for CRL (p = 0.93). Although FL was not statistically significant in the first trimester (p = 0.54), its measurement in the intervention group and the control group in the second (28.87 ± 2.14 vs. 26.89 ± 2.08; p ≤0.001) and the third (65.31 ± 2.17 vs. 62.85 ± 1.94; p ≤0.001) trimesters was significantly different. Femoral PMD, MSD, and DMD measurement increased more in the intervention group in comparison with the control group with P values <0.05. HL measurement in the intervention group and the control group in the second (28.62 ± 1.94 vs. 27.23 ± 2.08; p ≤0.001) and the third (61.29 ± 2.84 vs. 59.85 ± 1.79; p ≤0.001) trimesters revealed significant differences. Humeral PMD, MSD, and DMD measurement increased in the intervention group in comparison with the control group with P values <0.001 for all. It is suggested to prescribe low dose vitamin D (1000 IU per day) from early pregnancy with possible increment in length and diameter of femur and humerus bones of the fetus.

Selenomethionine potentiates the impact of vitamin D on thyroid autoimmunity in euthyroid women with Hashimoto's thyroiditis and low vitamin D status

BACKGROUND

Both exogenous vitamin D and selenium reduce thyroid antibody titers. The aim of the study was to investigate whether the impact of vitamin D on thyroid autoimmunity is affected by selenium intake.

METHODS

The study included 47 euthyroid women with Hashimoto's thyroiditis and low vitamin D status, 23 of whom had been treated with selenomethionine (200 μg daily) for at least 12 months before the beginning of the study. During the study, all patients were treated with vitamin D preparations (4000 IU daily). Serum titers of thyroid peroxidase and thyroglobulin antibodies, as well as circulating levels of thyrotropin, free thyroid hormones and 25-hydroxyvitamin D were measured before vitamin D supplementation and 6 months later. Moreover, at the beginning and at the end of the study, we calculated Jostel's thyrotropin index, the SPINA-GT index and the SPINA-GD index.

RESULTS

With the exception of the free triiodothyronine/free thyroxine ratio and the SPINA-GD index, there were no differences between the study groups. In both groups, vitamin D increased 25-hydroxyvitamin D levels, reduced thyroid peroxidase and thyroglobulin antibody titers, as well as increased the SPINA-GT index. The effects on antibody titers and the SPINA-GT index were more pronounced in women receiving selenomethionine. Neither in selenomethionine-treated nor in selenomethionine-naïve women vitamin D affected serum hormone levels, Jostel's index and the SPINA-GD index.

CONCLUSIONS

The results of the study suggest that selenium intake enhances the effect of vitamin D on thyroid autoimmunity.

The effect of vitamin D and selenomethionine on thyroid antibody titers, hypothalamic-pituitary-thyroid axis activity and thyroid function tests in men with Hashimoto's thyroiditis: A pilot study

BACKGROUND

Both selenium and vitamin D were found to reduce thyroid antibody titers in women with Hashimoto's thyroiditis.

METHODS

The study enrolled 37 young drug-naïve euthyroid men with autoimmune thyroiditis, who were treated for 6 months with either exogenous vitamin D (group A, n = 20) or selenomethionine (group B, n = 17). Serum titers of thyroid peroxidase and thyroglobulin antibodies, serum levels of thyrotropin and free thyroid hormones, serum levels of 25-hydroxyvitamin D, as well Jostel's thyrotropin, the SPINA-GT and the SPINA-GD indices were determined at the beginning and at the end of the study.

RESULTS

At baseline, there were no differences between the study groups. Both vitamin D and selenomethionine reduced antibody titers and increased the SPINA-GT index. Only selenomethionine affected the SPINA-GD index, while only vitamin D increased 25-hydroxyvitamin D levels. Neither selenomethionine nor vitamin D significantly affected thyrotropin and free thyroid hormone levels. The effect of vitamin D on antibody titers correlated with baseline and treatment-induced changes in serum levels of 25-hydroxivitamin D.

CONCLUSIONS

Both vitamin D and selenomethionine have a beneficial effect on thyroid autoimmunity in drug-naïve men with Hashimoto's thyroiditis.

Low Vitamin D Deficiency Associated With Thyroid Disease Among Type 2 Diabetic Mellitus Patients

BACKGROUND

The aim of this study was to investigate the relationship between vitamin D deficiency and thyroid diseases among type 2 diabetes mellitus (T2DM) patients.

METHODS

This was a cohort case and control study, 546 T2DM patients and 546 control study participants were enrolled, aged between 25 and 65 years. The subjects were also investigated for fasting blood glucose levels (FBG), post prandial glucose (PPG,) glycosylated hemoglobin (HbA1c), thyroid stimulating hormone (TSH), T3, T4, and presence of other comorbid conditions. Thyroid fine needle aspiration biopsy was suggested to patients whose thyroid nodules were greater than 1.00 cm.

RESULTS

There were significant differences between T2DM patients and control subjects regarding BMI (kg/m2), physical activity, cigarette smoking, sheesha smoking, family history of diabetes, hypertension and family history of thyroid nodules. The clinical biochemistry values among T2DM for vitamin D, calcium, magnesium, potassium, phosphorous, fasting blood glucose, cholesterol, HbA1c, HLDL, LDL, triglyceride, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were lower than control subjects, but higher in creatinine, albumin, TSH, T3, and T4 which appeared statistically significant differences (P < 0.001). Also, the study revealed statistically significant differences between subjects vitamin D deficiency and with thyroid nodules for calcium, magnesium, phosphorous, HbA1c, high density lipoprotein (HDL), SBP and DBP, TSH, T3, and T4 among T2DM patients and control subjects (P < 0.001). Multivariable stepwise logistic regression analysis showed that TSH, HbA1c, vitamin D deficiency, SBP (mm Hg), BMI, family history of DM, serum calcium level and family history of thyroid were considered at higher risk as predictors of thyroid among T2DM patients.

CONCLUSIONS

This study suggests that obesity, HbA1c, the environment, and genetic susceptibility among T2DM, may increase the risk of thyroid disease and cancer. Although evidence has shown that thyroid cancer incidence has been rising more rapidly over time than the occurrence of cancers of other sites, due to an increase of obesity, diabetes and lack of physical activity, this study lacks of direct evidence supporting this conclusion.

Vitamin D, autoimmunity and recurrent pregnancy loss: More than an association

Recurrent pregnancy loss (RPL) affects close to 1% of couples; however, the etiology is known in only about 50% of the cases. Recent studies show that autoimmune dysregulation is a probable cause of RPL, which in some cases may be overlooked. In order for a pregnancy to proceed to term, early modulation of immunologic response is required to induce tolerance to the semi-allogenic fetus. Certain subsets of both the innate and adaptive immune responses play a role in the induction of fetomaternal tolerance. A relatively predominant T-cell helper (Th) 2 and T regulatory (Treg) cell population seem to favor a better pregnancy outcome, whereas Th1 and Th17 cell populations appear to have an opposite effect. Lately, the role of vitamin D in the modulation of immune response was established. Vitamin D has been shown to promote a more favorable environment for pregnancy through various mechanisms, such as enhancement of the shift toward Th2 cells and regulation of immune cell differentiation and cytokine secretion. Therefore, it seems that vitamin D deficiency sways the balance toward a worse outcome and may play a part in recurrent pregnancy loss. This review sheds light on the immunologic changes, which occur in early pregnancy and the regulatory role vitamin D has in the maintenance of this delicate balance.

Hypothyrodism as a risk factor of periodontitis and its relation with vitamin D deficiency: mini-review of literature and a case report

Objective

The purpose of this report is to investigate the role and efficiency of the intra-ligamentary injection of vitamin D and calcium in the treatment of chronic periodontitis associated with hypothyroidism.

Design

A 43-year-old female with suspected hypothyroidism who revealed severe chronic periodontitis with grade III mobility. Pre-operative periodontal and systemic control preceded the used intervention. After 3 months, intra-ligamentary injectable vitamin D with calcium was introduced.

Results

Clinical evaluation revealed great improvement of the injected sites. Marked reduction of mobility, pocket depth and bleeding were detected.

Conclusions

Injectabe vitamin D is an adjunctive treatment modality that needs to be discovered in another way. It may provide further solutions for the periodontal regeneration problem. Clinical studies with large sample sizes and long term follow up are needed.

Vitamin D Deficiency and Immune Disorders in Combined Endocrine Pathology

Introduction: Combined endocrine pathology is a serious healthcare problem in Ukraine. This prospective study assessed the blood levels of 25-hydroxyvitamin D [25(OH)D] and markers of immune function in response to vitamin D intervention in patients with type 1 and type 2 diabetes mellitus (T1DM and T2DM, respectively) and autoimmune thyroiditis (AIT). Objective: This study evaluated the relationship between the metabolic and immune status of DM + AIT patients with respect to their vitamin D status and changes after vitamin D₃ supplementation. Material and Methods: Patients with type 1 or type 2 DM in combination with AIT and decreased circulating levels of 25(OH)D were divided into two groups of 30 patients each. All patients with AIT were euthyroid and receiving hormonal replacement therapy. The levels of carbohydrate and fat metabolism markers, Immunologic markers, namely, Th1-type cytokines [interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-2, IL-6, IL-12], Th2-type cytokines (IL-4, IL-5), IL-10, and IL-17 were measured before and after vitamin D₃ supplementation. The vitamin D status was assessed according to the level of 25(OH)D. Results: Patients with combined endocrine disorders (DM and AIT) with a decreased vitamin D status had significantly increased background concentrations of Th1-type cytokines and reduced concentrations of Th2-type cytokines (IL-4 and IL-5), IL-10, and IL-17. The results of our study showed that vitamin D₃ supplementation in patients with T1DM and T2DM reduced the concentrations of the inflammatory Th1-type cytokines and increased the levels of Th2-type cytokines. Conclusion: The presence of two endocrine diseases, aggravated by decreased circulating levels of 25(OH)D, leads to disorders wherein the immune status is markedly changed. These decreased levels of 25(OH)D contribute to an autoimmune inflammatory process and to the progression of complications in addition to the metabolic disorders. A vitamin D intervention resulted in significant changes in the blood levels of 25(OH)D that are related to parameters of autoimmunity and glucose metabolism. Vitamin D₃ supplementation should be considered for the prevention and treatment of combined endocrine pathology.

Vitamin D, FOXO3a, and Sirtuin1 in Hashimoto's Thyroiditis and Differentiated Thyroid Cancer

Background: Protective effects of vitamin D have been reported in autoimmune and malignant thyroid diseases, though little is known about the underlying mechanism. Sirtuin 1 histon deacethylase (SIRT1) links the vitamin D pathway with regulation of transcription factor FOXO3a, a key player in cell cycle regulation and apoptosis. Aim of the present study was to investigate common single nucleotide polymorphisms (SNP's) in FOXO3a gene in respect to thyroid diseases, as well as to evaluate the hypothesis of Sirtuin1-FOXO3a interaction being a mediator of anti-proliferative vitamin D effects. Methods: The SNP's FOXO3a rs4946936/rs4945816/rs9400239 were genotyped in 257 patients with differentiated thyroid carcinoma (DTC), 139 patients with Hashimoto thyroiditis (HT) and 463 healthy controls (HC). Moreover, T-helper cells of HC and papillary thyroid cancer cell line BCPAP were incubated with 1,25(OH)₂D₃ and/or SIRT1 inhibitor Ex-527 in order to elucidate SIRT1- dependent vitamin D effects on cell proliferation and FOXO3a gene expression in vitro. Results: Patients with DTC tended to carry more often allele C in FOXO3a rs4946936 in comparison to HC (p_corrected = p_c = 0.08). FOXO3a rs9400239T and rs4945816C was more frequent in HT in comparison to HC (p_c = 0.02 and p_c = 0.01, respectively). In both DTC and HT, we could not find a correlation of FOXO3a SNP's with vitamin D status. However, on in vitro level, 1,25(OH)₂D₃ showed an anti-proliferative effect in both T-helper cells and BCPAP, that was blocked by SIRT1 inhibition (T-helper cells: p = 0.0059, BCPAP: p = 0.04) and accompanied by elevated FOXO3a gene expression in T-helper cells (p = 0.05). Conclusions: FOXO3a rs9400239T and rs4945816C may constitute risk factors for HT, independent of the vitamin D status.This indicates the implication of FOXO3a in pathogenesis of autoimmune thyroid diseases. The dependency of anti-proliferative vitamin D effects on SIRT1 activity further suggests a key role of vitamin D-SIRT1-FOXO3a axis for protective vitamin D effects.