Thyroid Antibody Status Research Articles

Antithyroid antibody (TPO-Ab) Status in Type 2 Diabetic Patients

Background: Presence of thyroid peroxidase antibody (TPO-Ab) in type 2 diabetic patients is a risk factor for future development of thyroid dysfunction.Objective: To observe thyroid antibody status in type 2 diabetic patients.Materials & Methods: This cross sectional study was carried out in the Department of Physiology, Sir Salimullah Medical College, Dhaka from July 2016 to June 2017. Total 60 subjects including male and female, age ranged from 40 to 60 years were included in this study, among them 30 were non-diabetic subjects and 30 were type 2 diabetic patients.Results: In this study, mean serum TPO-Ab level was significantly (<0.01) higher in diabetic subjects in comparison to that of apparently healthy non-diabetic subjects and mean serum TPO-Ab level was higher in uncontrolled diabetic subjects in comparison to that of controlled diabetic subjects but the difference is not statistically significant. However, On the other hand, among the diabetic patients 6.67% had positive TPO-Ab whereas, among the uncontrolled diabetic patients 11.76% had positive TPO-Ab. There was no correlation between TPO-Ab and HbA1c.Conclusion: The present study reveals that TPO-Ab may present in type 2 diabetic patients. KYAMC Journal Vol. 14, No. 01, April 2023: 35-38

Role of Serum Thyroid Antibody Status in Predicting Checkpoint Inhibitor–Associated Thyroid Immune-Related Adverse Events

Role of Serum Thyroid Antibody Status in Predicting Checkpoint Inhibitor–Associated Thyroid Immune-Related Adverse Events

Effects of animal protein intake during pregnancy on autoimmune thyroiditis in pregnant women with mild iodine deficiency.

Iodine and animal protein may affect thyroid function. In the present study, we explored the association between animal protein intake and thyroid antibody status in pregnant women following universal salt iodisation. Pregnant women were enrolled using a multistage, stratified random sampling method in Shanghai. In total, 4646 eligible women were interviewed in person. We used a validated food frequency questionnaire and food composition tables to calculate the daily intakes of protein and iodine. We collected urine samples and performed thyroid antibody tests. Positive thyrotropin receptor antibody (TR-Ab) rates were different among animal protein intake groups (p < 0.05). Median urinary iodine concentration (UIC) was higher in the thyroid peroxidase antibody (TPO-Ab) positive group than in the negative group (p < 0.05). The median of total protein intake, animal protein intake and UIC was higher in the TR-Ab positive group than in the negative group (p < 0.05). The median of total protein intake and UIC was higher in the TPO-Ab/TG-Ab/TR-Ab positive group than in the negative group (p < 0.05). Multivariable logistic regression results showed that insufficient iodine had a negative correlation with positive TPO-Ab and positive TR-Ab (p < 0.05). The middle third and top third animal protein intakes served as protective factors for TR-Ab (coefficient = 0.559, 95% confidence interval [CI] = 0.415-0.752, p < 0.001; coefficient = 0.0.406, 95% CI = 0.266-0.621, p < 0.001) and positive TPO-Ab/TR-Ab/TG-Ab (coefficient = 0.817, 95% CI = 0.687-0.971, p = 0.022; coefficient = 0.805, 95% CI = 0.672-0.964, p = 0.018). Adequate animal protein intake protects against elevated anti-thyroid antibody levels in pregnant women with mild iodine deficiency.

Is climacterium by the mid-40s associated with thyroid dysfunction or autoimmunity? A population-based study.

We investigated whether more advanced climacteric stage in the mid-40s is associated with thyroid autoimmunity and dysfunction. This cross-sectional cohort study included 2,569 46-year-old women. Thyroid hormone, thyroid peroxidase antibodies, and follicle-stimulating hormone levels were determined. Using menstrual history and follicle-stimulating hormone levels, the participants were divided into climacteric (n = 340) and preclimacteric (n = 2,229) groups. Women diagnosed with premature ovarian insufficiency (menopause by 40 y of age) were excluded. The use of thyroid medication was evaluated from the medication reimbursement register. The prevalence of thyroid medication use, laboratory-based thyroid dysfunction, and thyroid peroxidase antibody positivity was compared between the two groups. The association between climacteric status and thyroid disorders was investigated using a logistic regression model including smoking and thyroid antibody status. At 46 years old, climacteric women used thyroid medication more often than preclimacteric women (9.1% vs 6.1%; P = 0.04). There was no difference in the prevalence of subclinical or clinical hypothyroidism and hyperthyroidism in nonmedicated participants (5.5% vs 5.0%; P = 0.7) or thyroid peroxidase antibody positivity (14.0% vs 15.0%, P = 0.7). In the regression model, being climacteric (OR = 1.6; 95% CI 1.1-2.3; P = 0.02) and antibody positivity (OR 4.9; 95% CI 3.6-6.6; P < 0.001) were associated with a higher prevalence of thyroid dysfunction. More advanced climacteric stage in the mid-40s was slightly associated with thyroid dysfunction but not thyroid autoimmunity.

Is the link between elevated TSH and gestational diabetes mellitus dependant on diagnostic criteria and thyroid antibody status: a systematic review and meta-analysis.

Clinical studies have investigated the prevalence of gestational diabetes mellitus (GDM) in women with subclinical hypothyroidism (SCH). While some studies demonstrate a clear association, others do not. It is possible this may be due to varied diagnostic criteria for SCH and the presence of thyroid antibodies (TA). We conducted a meta-analysis, separating patients diagnosed with SCH using a diagnostic cut-off <4.0 mIU/L from those diagnosed using a cut-off >4.0 mIU/L and determined the association with GDM and factored TA status into our analysis. A computerised search of five databases including PubMed, Embase, Cochrane Library, Web of Science and CINAHL returned 787 records. Two independent reviewers assessed abstracts and full texts against pre-specified inclusion and exclusion criteria. Ten cohort studies were included in the final analysis. The diagnostic criteria for SCH and incidence of GDM were extracted from each study. Study quality and risk of bias was assessed by two reviewers. TSH levels <4.0 mIU/L for SCH diagnosis was not associated with GDM unless patients were TA positive. Studies that used a diagnostic cut-off >4.0 mIU/L saw a significant increase in the odds of GDM, regardless of TA status (OR = 1.60, 95% CI 1.33-1.93). Women with TSH levels >4.0 mIU/L have an increased odds of GDM regardless of TA status but at TSH levels <4.0 mIU/L, GDM is dependent on TA status. The use of TSH levels to identify pregnancies at risk of GDM is a novel concept that warrants exploration.

Association of thyroid antibodies status on the outcomes of pregnant women with hypothyroidism (maternal hypothyroidism on pregnancy outcomes, MHPO-4)

BackgroundAutoimmunity increases with age and is often commonly evaluated in women of the reproductive age group. Prevalence of thyroid antibodies is common even in euthyroid pregnant women. We aim to compare the association of thyroid antibody status on the maternal and neonatal outcomes in pregnant women with hypothyroidism.MethodsWe conducted a cross-sectional retrospective study on 718 cases in the Aga Khan University Hospital. Information was collected on pregnant women who have been diagnosed with hypothyroidism before conception or during their antenatal period. Laboratory data were recorded for thyroid peroxidase antibodies, anti-thyroglobulin antibodies, and thyroid-stimulating hormone levels. Maternal and neonatal outcomes were also noted from medical file records. Data analysis was performed on Statistical Package for the Social Sciences version 20.0.ResultsOverall, 146 out 718 cases were included for final analysis. Thyroid peroxidase antibodies were positive in 66.4% and anti-thyroglobulin was positive in 52.1% cases, whereas 43.8% of cases had both antibodies positive. Pre-gestational diabetes was significantly associated with thyroid autoimmunity. There was a 73% less chance of gestational hypertension for thyroid autoimmune groups. Gestational diabetes and maternal (chronic) hypertension were found to have an independent effect on postpartum hemorrhage. Hypertensive disorders in pregnancy were found to have an independent risk for premature birth.ConclusionOur study reports a 74.7% prevalence of positive thyroid antibodies in hypothyroid pregnant women, with higher association with pre-gestational diabetes. Gestational hypertension was least likely to occur in thyroid autoimmune groups. None of the outcomes were independently associated with worse outcomes.

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

Background: There are scarce data on the prevalence of thyroid disorders and urinary iodine status among tribal populations of India, with no reported data from Kashmir valley.Objectives: To estimate the prevalence of thyroid disorders and evaluate urinary iodine concentration (UIC) and thyroid autoantibody status among Gujjar and Bakerwal tribes of Kashmir valley.Methods: This cross-sectional study recruited tribal subjects using multistage cluster sampling from 5 out of 22 districts of Jammu and Kashmir (J&K). Using a predesigned questionnaire, the details of past or current medical history and drug intake, including thyroid hormone medication etc. were recorded after obtaining an informed consent. Examination included anthropometry (height, weight, waist circumference), blood pressure measurement, and relevant general physical examination focusing on goiter palpation, while as laboratory assessment included estimation of serum thyroid hormone levels, antithyroid peroxidase antibody (anti-TPO Ab), and urinary iodine concentration.Results: A total of 763 subjects (56.4% women and 43.6% men) with a mean(±SD) age of 39.46 (±17.51) ranging from 10 to 85 years and mean(±SD) body mass index (BMI) of 21.28 (±4.16) kg/m2 were studied. Goiter was detected in 6.8%, while 33.2% subjects had some form of thyroid dysfunction (including 24.1% subclinical and 6.8% overt hypothyroidism). Subclinical and overt hyperthyroidism were observed in 1.3 and 0.9% of cases, respectively. Anti-TPO Ab was elevated in 13.6%, while the median [interquartile range (IQR)] for UIC was 154.50 (135) μg/L [156.13 (134) μg/L in men and 147.26 (136) μg/L in women]. A negative correlation was observed between UIC and anti-TPO Ab (r = −0.087, P = <0.05).Conclusion: These novel data on iodine and thyroid status among a tribal population of India generally inhabiting in remote sub-Himalayan belts demonstrate high prevalence of subclinical hypothyroidism (SCH) with persistent iodine deficiency. These preliminary data may warrant large well-designed studies to carry out comprehensive assessment of the problem in this high-risk and marginalized population.

Thyroid antibody status exerts insignificant effect on lymph node metastasis of thyroid cancer.

BackgroundTo investigate whether high thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb) levels are associated with increased risk of lymph node metastasis (LNM) of thyroid cancer.MethodsData of 2,352 patients who committed thyroidectomy from January 2018 to December 2018 at our institution were retrospectively reviewed. Of which, 806 patients diagnosed with thyroid cancer with available data of both TPOAb and TgAb were finally included, and were divided into four groups: (I) TPOAb−/TgAb− (control, n=493), (II) TPOAb+/TgAb− (n=96), (III) TPOAb−/TgAb+ (n=104), and (IV) TPOAb+/TgAb+ (n=113). The demographic and clinicopathological data were analyzed.ResultsCompared to control, significantly less extrathyroidal invasions were identified in TPOAb+ and/or TgAb+ patients (P<0.05), while no significant differences for tumor size, multifocality, or central/lateral neck LNM rate were found for TPOAb+ and/or TgAb+ groups (all P>0.05). Compared to control, significantly more lymph nodes were removed during neck dissection (P<0.05), but there were no significant differences for the number or size of lymph nodes involved (all P>0.05) for TPOAb+ and/or TgAb+ patients. TPOAb+ and/or TgAb+ were not identified as risk factors or protect factors of LNM of thyroid cancer in Logistic regression analyses.ConclusionsIn the present study, we demonstrated that anti-thyroid peroxidase and thyroglobulin antibodies are not associated with increased risk of lymph node metastasis of thyroid cancer.

Compared with classic Hashimoto’s thyroiditis, chronic autoimmune serum-negative thyroiditis requires a lower substitution dose of l-thyroxine to correct hypothyroidism

Serum-negative-chronic-autoimmune-thyroiditis (SN-CAT) is considered a milder variant of classic Hashimoto's thyroiditis (CHT). However, its prevalence remains unknown and it is still unclear whether SN-CAT behaves differently in terms of L-thyroxine (LT4) substitution treatment of hypothyroidism. Aims of this study were to estimate the prevalence of SN-CAT in a large series of hypothyroid patients and to compare LT4 requirements in hypothyroid patients with SN-CAT and CHT. Five-hundred-eighty-one consecutive patients with primary-autoimmune-hypothyroidism were enrolled in a cross-sectional study. LT4 requirements and thyroid-volume changes were longitudinally evaluated in 49 hypothyroid patients with SN-CAT and in 98 sex and age-matched hypothyroid patients with CHT. In our series the prevalence of SN-CAT was 20.8%. At diagnosis, patients in the CHT and SN-CAT groups had similar male/female ratio, age and BMI, while serum TSH and thyroid-volume were significantly greater in the CHT group. In the longitudinal study, during a follow-up of 8.9 ± 4.6years, 8 out of 49 (16.3%) SN-CAT patients developed positive tests for of circulating TPO-Ab and/or Tg-Ab. Thyroid-volume significantly decreased in CHT patients, but not in those with SN-CAT. The maximum daily substitution dose of LT4 was smaller in SN-CAT patients as compared with the CHT ones. Multivariate analysis showed that age, BMI, basal TSH and thyroid antibody status independently and significantly predicted the maximum daily substitution dose of LT4. SN-CAT accounts for a significant proportion of patients with autoimmune hypothyroidism. Compared with hypothyroid patients diagnosed with CHT, the SN-CAT ones require smaller doses of LT4 to correct their hypothyroidism.

Targeted Antenatal Screening for Predicting Postpartum Thyroiditis and Its Evolution Into Permanent Hypothyroidism.

Postpartum thyroiditis (PPT) has a prevalence of 1–22%, with an ~50% rate of evolution into permanent hypothyroidism (PH). PPT risk is assessed by measuring serum thyroid antibodies during gestation, as 1/3–1/2 of Ab+ve pregnant women will develop PPT. Family and personal history positive for autoimmune non-thyroid diseases (AINTDT), and consumption of swordfish increases while consumption of small oily fish decreases the risk of PPT. Monitoring thyroid function in a very high-risk subgroup avoids the costs of the Ab-based universal screening. We aimed at identifying such subgroup in 412 women followed from week 7–11 of gestation to month 12 postpartum. At study entry, we measured serum TPOAb, TgAb, TSH, FT4, FT3, and evaluated seafood consumption, familial history for thyroid diseases and AINTD, and personal history for AINTD. We measured TSH, FT4, FT3 at 1.5, 3, 6, and 12 months postpartum. PPT occurred in 63 women (15.3%), and PH in 34/63 (54%). Based on positivity/negativity for the three histories, women were classified into 8 categories, with PPT rates of 3.8–100%. Seafood consumption allowed further separation of subgroups having different PPT risks. We considered 11 possible strategies, termed [a] through [k]. Strategy [a] consisted in omitting gestational screening, while performing universal postpartum monitoring with TSH and one thyroid hormone; strategy [k] consisted in selective gestational screening with TPOAb and TgAb, based on history and fish consumption, and selective postpartum monitoring in TPOAb and/or TgAb+ve women. The 100% sensitivity, specificity and diagnostic accuracy of strategy [a] were counterbalanced by the highest costs (Euro 32,960 or 523 per each PPT caught). The corresponding numbers for strategy [k] were 78, 95, 93%, and Euro 8,920 or 182/PPT caught. These savings stem from gestational screening being done in 186 women, and postpartum monitoring done in 65/186 women. One gestational screning-free strategy was the cheapest (Euro 2,080 or 83/PPT caught), because based on postpartum monitoring of only 26 women, but had the lowest sensitivity (40%). Identification of pregnant women having different risks for PPT is feasible, with the costless evaluation of history and seafood consumption driving gestational screening of thyroid antibody status and postpartum monitoring of thyroid function.

Prenatal dioxin exposure and thyroid hormone levels in the Seveso second generation study

BackgroundIn animal studies, perinatal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) alters thyroid homoeostasis and thyroid hormone concentrations; epidemiologic evidence is limited. ObjectivesWe aimed to determine the association of prenatal exposure to TCDD with thyroid hormone concentrations in the Seveso Second Generation Study, a unique cohort of children born to TCDD-exposed women resulting from a 1976 chemical factory explosion in Seveso, Italy. MethodsWe included 570 children (288 female, 282 male) with complete follow-up data, including a fasting blood draw. Serum levels of total and free thyroxine (T4), free triiodothyronine (T3), and thyroid stimulating hormone (TSH) were measured using immunoassays. We defined prenatal TCDD exposure as: 1) maternal initial TCDD concentration measured in serum collected soon after the explosion and 2) maternal TCDD estimated at pregnancy. ResultsCompared to the lowest quartile (Q1), maternal initial serum TCDD was associated with lower free T3 (Q2: adj-β = −0.13, 95%CI -0.26, 0.00; Q3: adj-β = −0.22, 95%CI -0.35, −0.09; Q4: adj-β = −0.14, 95%CI -0.28, 0.00; p-trend = 0.02). In participants with high thyroid antibody status, inverse associations between maternal initial serum TCDD and free T3 were significantly stronger than in participants with normal antibody status (p-interaction = 0.02). We also observed a positive association between maternal initial serum TCDD and TSH concentrations in participants with high thyroid antibody status (Q2: adj-β = 11.4%, 95%CI -25.2, 66.1; Q3: adj-β = 49.0%, 95%CI 3.0, 115.5; Q4: adj-β = 105.5, 95%CI 36.6, 209.2; p-trend < 0.01) but not in those participants with normal antibody status (p-interaction < 0.01). Similar results were found for TCDD estimated at pregnancy. DiscussionOur results suggest prenatal exposure to TCDD, a potent endocrine-disrupting compound, may alter thyroid function later in life. Populations with additional thyroid stress may be particularly susceptible to in utero exposure of thyroid disrupting chemicals.

Thyroid Antibody Status is Associated with Central Lymph Node Metastases in Papillary Thyroid Carcinoma Patients with Hashimoto’s Thyroiditis

The aim of this study was to explore the impact of thyroid antibody status on central lymph node metastases (CLNM) in papillary thyroid carcinoma (PTC) patients with Hashimoto's thyroiditis (HT). A retrospective analysis was performed on 346 PTC patients with HT who underwent thyroidectomy and ipsilateral central lymph node dissection (CLND). Histopathological characteristics of the tumor and serum levels of thyroid hormone, as well as antibodies, were collected and analyzed. The multivariate logistic regression analysis showed that being male [odds ratio (OR) 3.269, 95% confidence interval (CI) 1.240-8.619], tumor size > 1cm [1cm < diameter (D) ≤ 2cm: OR 6.947, 95% CI 2.886-16.722; 2 cm < D: OR 5.880, 1.937-17.846], and antibody status [thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb) double negative: OR 3.791, 95% CI 1.391-10.331; TPOAb and TgAb double positive: OR 4.047, 95% CI 1.509-10.856; TgAb single positive: OR 6.024, 95% CI 2.019-17.970] were independent risk factors for CLNM. Additionally, a risk-score scale, including sex, antibody status, and tumor size, was established to predict CLNM. The sensitivity, specificity, positive predictive value, and negative predictive value were 55.7%, 84.4%, 74.4%, and 70%, respectively, when the cut-off point was chosen as 3. Antibody status is a critical independent risk factor for CLNM in PTC patients with HT. For the CLND strategy, a more conservative option could be considered in a low-risk cohort with the following characteristics: female sex, smaller tumor size, and TPOAb single positive.

Does severe vitamin D deficiency impact obstetric outcomes in pregnant women with thyroid autoimmunity?

Purpose: Vitamin D plays an important role in the modulation of the immune system and anti-autoimmune activities. Autoimmune thyroid diseases related to endocrine disorders are associated with poor obstetric outcomes in pregnancy. Herein, we aimed to investigate the contribution of vitamin D hypovitaminosis to poor pregnancy outcomes in pregnant women with the positive autoimmune antibody.Materials and methods: This was a prospective case–control study that enrolled pregnant women at their first trimester. The pregnant women were divided based on thyroid antibody (TA) status (TA-positive pregnant group (TAs (+)) and negative group (TAs (−)). Vitamin D status was categorized as sufficient, insufficient, and deficient (severe and moderate).Results: A total of 283 pregnant women were enrolled in this study. A total of 219 pregnant women were assigned to the TAs (−) group and 64 to the TAs (+) group. The rate of vitamin D insufficiency was 8.7, and 7.8% in the pregnant with TAs (−), and the pregnant with TAs (+) groups, respectively. Vitamin D deficiency was highly prevalent in all groups. Specifically, the prevalence rate was 91 and 92% in the pregnant with TAs (−) and the pregnant with TAs (+) groups, respectively. Admission to the neonatal intensive care unit (NICU) was more prevalent in the pregnant with TAs (+) group than in the pregnant with TAs (−) group (40.6 versus 25%; p = .0187; effect size (ES) = 0.134). The rate of gestational diabetes mellitus (GDM) was significantly higher in the pregnant women with TAs (+) group than that in the pregnant women with TAs (−) group (12.5 versus 4.1%; p = .03; ES =0.13). The rate of NICU admission and GDM was significantly higher in the severe vitamin D-deficient pregnant group with TAs (+) than that in the severe vitamin D-deficient pregnant group with TAs (−) (47 versus 23%; p = .007; ES =0.207 and 19.4% versus 4.1%; p = .006; ES =0.214, respectively).Conclusions: Severe vitamin D deficiency may contribute to increase the prevalence of GDM and need for NICU admission in pregnant women with positive TA.

Management of Subclinical Hypothyroidism in Pregnancy: A Comment from the Italian Society of Endocrinology and the Italian Thyroid Association to the 2017 American Thyroid Association Guidelines-"The Italian Way".

The 2017 American Thyroid Association guidelines for the diagnosis and management of thyroid disease during pregnancy and the postpartum were published six years after the previous ones. They provide comprehensive clinical recommendations for the whole spectrum of thyroid diseases, as well as for optimal iodine intake during pregnancy, postpartum, and lactation. The present position statement mainly regards the recommended flow chart for therapeutic decision making in pregnant women being diagnosed with subclinical hypothyroidism. Here, we comment on the major biochemical and clinical situations and the corresponding therapeutic recommendations. In particular, we welcome the critical revision of the thyrotropin (TSH) reference range in pregnancy, and we agree that there is no need to treat thyroid peroxidase antibody-negative women with a serum TSH ranging from 2.5 μIU/mL to the upper limit of the reference range. This recommendation will hopefully reduce the huge proportion of healthy pregnant women in whom, according to the previous guidelines, levothyroxine therapy had to be initiated. On the other hand, we are concerned with the recommendation to only "consider treatment" in thyroid peroxidase antibody-negative pregnant women with a serum TSH ranging from the upper limit of the reference range to 10.0 μIU/mL. This is because thyroid antibodies may be falsely negative during gestation, and serum negative chronic autoimmune thyroiditis is a well-known clinical entity even outside pregnancy. Based on these and other arguments, we recommend treatment with levothyroxine in pregnant women with TSH levels ranging between the upper limit of the reference range and 10.0 μIU/mL independently from their thyroid antibody status.

Trimester-Specific Reference Intervals of Thyroid Function Testing in Pregnant Women from Basrah, Iraq Using Electrochemiluminescent Immunoassay.

Background: Thyroid function test results of healthy pregnant women differ from those of healthy non-pregnant women. This study aimed to determine trimester-specific reference ranges for total tetraiodothyronin (T4), free T4, total triiodothyronin (T3) and thyroid stimulation hormone (TSH) using electrochemiluminescence techniques from apparently healthy pregnant women in Basrah. Material and Methods: A cross sectional study was conducted between January 2014 and June 2015. The total enrolled pregnant women were 893. Clinical examination, estimation of free T4, total T4, total T3, TSH, and anti-thyroid peroxidase (anti-TPO) using electrochemiluminescence technique done for each. Results: Trimester specific normal range of TSH in μIU/mL was 0.04–3.77, 0.30–3.21 and 0.60–4.50 μIU/mL respectively, for each trimester. For FreeT4, the trimester specific reference range was 0.8–1.53, 0.7–1.20 and 0.7–1.20 ng/dL for each trimester, respectively. The reference range for total T4 for the first, second and third trimester was 7.31–15.00, 8.92–17.38, and 7.98–17.70 μg/dL, respectively. Furthermore, last trimester specific reference range for total T3 was 0.90–2.51, 1.99–2.87 and 1.20–2.70 ng/mL, respectively. Conclusion: Using this thyroid function study, we established for first time trimester-specific reference ranges for each thyroid function test and thyroid antibody status for the first time in Iraq. The reference ranges are different from all previous studies outside Iraq and the reference kit range from the method we used.

Absence of a relationship between thyroid hormones and vitamin D levels.

Vitamin D is an immune modulator that may play a role in thyroid related autoimmunity. We analyzed a US population based dataset to determine the relationship between serum 25-hydroxyvitamin D (25OHD) and thyroid hormones while assessing the effects of autoimmunity and BMI. 25OHD did not correlate significantly with any thyroid related measure. 25OHD levels stratified by thyroid antibody status were not statistically different between antibody positive and negative groups. The mean 25OHD levels of lean, overweight, and obese groups defined by BMI were lower than those of the normal group. Only the mean thyroid stimulating hormone (TSH) value in the obese group was significantly higher than the normal group. We conclude that thyroid related measures and 25OHD serum levels are not related.

Autoimmune Thyroiditis in Women of Child Bearing Age and its Association with Thyroid Function and Thyroid Antibody Status

Thyroid disorders are prevalent in women of childbearing age and for this reason commonly present in pregnancy and the puerperium. Chronic autoimmune thyroiditis (AIT) is the most common and extensively studied organ-specific autoimmune disorder and it has important consequences on fertility, the occurrence of pregnancy complications and pregnancy outcome. Across sectional analytical study has been carried out on autoimmune thyroiditisamong the women of child bearing age with suspected thyroid disorders in the Centre for Nuclear Medicine &amp; Ultrasound, Mymensingh during the period of July, 2011 to June, 2012.The objectives of the study were to estimate the prevalence of autoimmune thyroiditis in women of child bearing age and to determine the association of autoimmune thyroiditis with thyroid function and thyroid antibody status. In the present study, 100 women of childbearing age (15-45Yrs) with any sorts of suspected thyroid disorders were included. But already diagnosed all follow up cases were excluded from the study. High Resolution Ultrasonography (HRUS) had been taken as principal modality of diagnosis of autoimmune thyroiditis. T3, T4 and TSH were taken as an important indicator for thyroid function status. Serum TM-Ab (Thyroid Microsomal Antibody) level and serum Tg-Ab (Thyroglobulin Antibody) level were measured to see the thyroid antibody status. In the present study, prevalence of autoimmune thyroiditis among the women of childbearing age with suspected thyroid disorders was found 41%. According to the thyroid function status, 65.85% AIT patients were found in hypothyroid state, 29.27% in subclinical hypothyroid state and rest 4.88% were found in euthyroid state. In consideration of thyroid antibody status, 69.23% AIT patients were positive &amp; 30.77% were negative for thyroid autoantibody. This study revealed that there were significant association of AIT with the biochemical hypothyroid state and positive thyroid antibody status DOI: http://dx.doi.org/10.3329/bjnm.v17i1.22487 Bangladesh J. Nuclear Med. 17(1): 14-24, January 2014

Associations between thyroid autoantibody status and abnormal pregnancy outcomes in euthyroid women.

We investigated whether thyroid autoantibody status influences pregnancy outcomes in euthyroid women, by comparing abnormal pregnancy outcome rates between those who tested positive for thyroid autoantibodies (Ab+) and those who tested autoantibody-negative (Ab-). Euthyroid pregnant women (n=7,641) underwent tests for serum thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb). The subjects were divided into 4 groups according to thyroid antibody status: TPOAb-/TgAb- (92.9%); TPOAb+/TgAb- (3.2%); TPOAb-/TgAb+ (2.0%); and TPOAb+/TgAb+ (1.9%). The incidence rates of the following abnormal pregnancy outcomes were compared among the 4 groups and analyzed by Fisher's exact test: gestational diabetes, gestational hypertension, placenta previa, placental abruption, premature rupture of fetal membrane (PROM), intrauterine growth restriction, fetal distress, fetal anomalies, stillbirth, preterm birth, and low birth weight. Among the 4 groups, there were no significant differences in age, gestational age, or in the incidence rates of abnormal pregnancy outcomes, except for PROM and low birth weight. The highest incidence rates for PROM and low birth weight were in the TPOAb-/TgAb+ and TPOAb+/TgAb+ subjects, respectively. TgAb positivity and TPOAb positivity were associated with PROM and low birth weight, respectively. Underlying factors that govern the association between thyroid autoantibodies and PROM and low birth weight require further investigation.

Thyroid antibody status, subclinical hypothyroidism, and the risk of coronary heart disease: an individual participant data analysis.

Subclinical hypothyroidism has been associated with increased risk of coronary heart disease (CHD), particularly with thyrotropin levels of 10.0 mIU/L or greater. The measurement of thyroid antibodies helps predict the progression to overt hypothyroidism, but it is unclear whether thyroid autoimmunity independently affects CHD risk. The objective of the study was to compare the CHD risk of subclinical hypothyroidism with and without thyroid peroxidase antibodies (TPOAbs). A MEDLINE and EMBASE search from 1950 to 2011 was conducted for prospective cohorts, reporting baseline thyroid function, antibodies, and CHD outcomes. Individual data of 38 274 participants from six cohorts for CHD mortality followed up for 460 333 person-years and 33 394 participants from four cohorts for CHD events. Among 38 274 adults (median age 55 y, 63% women), 1691 (4.4%) had subclinical hypothyroidism, of whom 775 (45.8%) had positive TPOAbs. During follow-up, 1436 participants died of CHD and 3285 had CHD events. Compared with euthyroid individuals, age- and gender-adjusted risks of CHD mortality in subclinical hypothyroidism were similar among individuals with and without TPOAbs [hazard ratio (HR) 1.15, 95% confidence interval (CI) 0.87-1.53 vs HR 1.26, CI 1.01-1.58, P for interaction = .62], as were risks of CHD events (HR 1.16, CI 0.87-1.56 vs HR 1.26, CI 1.02-1.56, P for interaction = .65). Risks of CHD mortality and events increased with higher thyrotropin, but within each stratum, risks did not differ by TPOAb status. CHD risk associated with subclinical hypothyroidism did not differ by TPOAb status, suggesting that biomarkers of thyroid autoimmunity do not add independent prognostic information for CHD outcomes.

Commentary: Iodine deficiency as a new challenge for industrialized countries: A UK perspective

The World Health Organization (WHO) estimates that worldwide 2 billion people, including 285 million school-age children, still have iodine deficiency despite major national and international efforts to increase iodine intake, primarily through the voluntary or mandatory iodization of salt. Iodine deficiency has substantial effects on growth and development and is the most common cause of preventable mental impairment worldwide. Although endemic cretinism had been long recognized to be associated with iodine deficiency, the article from Pharoah, Buttfield and Hetzel in 1971 recognized the importance of severe iodine deficiency and its correction in early pregnancy in a classic interventional epidemiological study. The recent Copenhagen Consensus of 2008 (www.copenhagenconsensus.com) identified salt iodization as the third most important and cost-effective intervention for confronting ten great global challenges. Although the introduction of iodized salt has considerably improved the situation globally in the developing world, iodine deficiency remains an issue in continental Europe where it is estimated that up to 50% of the children live in iodine-deficient communities. Mild iodine deficiency impairs cognition in children, and moderate to severe iodine deficiency in a population reduces the intelligence quotient by 10–15 points. Iodine supplementation pre-pregnancy may prevent this adverse effect on the intellectual development of infants and children. Mild to moderate iodine deficiency occurs in areas that are not immediately recognized as iodine deficient. Iodine deficiency has historically been considered an issue for developing countries rather than industrialized countries such as the UK. Endemic goitre associated with iodine deficiency was at one time widespread in the UK and Medical Research Council surveys in 1924 and 1944 reported visible goitre in up to 50% of the adult women and schoolgirls. No salt iodization programme was adopted in the UK unlike in other European countries. Since the 1940s, significant changes in farming practice in the UK were associated with a rise in the iodine content of milk, particularly during winter months when cattle are dependent on iodine-rich artificial feed. In addition, successive UK governments from the 1940s encouraged increased milk consumption in schoolchildren. By the 1980s, this resulted in the iodine content of milk alone being almost sufficient to meet the recommended daily requirement of 150 mg/day and has been described as an ‘accidental public health triumph’. Although national monitoring of milk iodine content continued, the major concern was to avoid the harmful effects of iodine toxicity rather than deficiency. My interest in thyroid epidemiology was stimulated where as a research fellow in Newcastle-upon-Tyne working with Mike Tunbridge who had led the original Whickham survey documenting the prevalence of thyroid disorders in a representative sample of the UK in the early 1970s. Sixteen percent of the cohort had small but easily palpable diffuse or multinodular goitres. In men, the prevalence of goitre declined with age from 7% in those aged <25 years to 4% in those aged 65–74 years. Among the women, 26% had a goitre; the frequency ranged from 31% in those aged <45 years (mostly diffuse) to 12% in those aged over 75 years (who had a higher proportion of multinodular goitre). In the 20-year follow-up of the Whickham cohort, 10% of the women and 2% of the men had a goitre, as compared with 23 and 5% respectively, in the same subjects at the first survey. The presence of a diffuse goitre was not predictive of any clinical or biochemical evidence of thyroid dysfunction. In women, there was no association between goitre and thyroid antibody status in the initial survey but at the 20-year follow-up, there was a weak association. Although the order in which these events occurred is unknown, it suggested an autoimmune aetiology for some goitres. In 1995, the median Published by Oxford University Press on behalf of the International Epidemiological Association