Thyroid-stimulating Hormone Concentrations Research Articles

Association of pro-atherogenic risk factors with thyroid-stimulating hormone level in women 25–44 years old

Thyroid hormones play an important role in regulating metabolism. A large body of literature suggests an increased risk of developing metabolic syndrome (MS) in individuals with hypothyroidism, but little data exists on the effects of high-normal levels of thyroid-stimulating hormone (TSH) on metabolism.Material and methods. The study was conducted on a representative sample of people aged 25–44 years (n = 1513, of which 840 were women). The analysis included the results of 343 women. A questionnaire, anthropometric and biochemical study were carried out. Biochemical parameters were analyzed in quartiles of TSH content. Determination of MS was carried out using the criteria of NCEP ATP III (2001), IDF (2005), VNOK (2009).Results. TSH content in the examined sample was 1.5 [1.0; 2.2] mU/l (median [lower quartile; upper quartile]). Among women 25–44 years old, women with highly normal TSH level (3.1 [2.7, 3.8] mU/l) have less favorable metabolic parameters. MS was detected in 31 % cases, with a predominant increase in the frequency of abdominal obesity – in 51 %, with increased triglyceride levels in 18 %. Women with hypertriglyceridemia had higher TSH content than those with normal triglyceride levels (2.4 ± 1.6 vs. 1.8 ± 1.3 mU/L, respectively, p = 0.007).Conclusions. In women 25–44 years of age, high-normal TSH content is more often associated with metabolic unhealth.

Correlation of Serum Prolactin and Thyroid Stimulating Hormone Concentration in Infertile Women: A Systematic Review and Meta-Analysis.

Infertility affects millions of people of reproductive age worldwide. Thyroid hormones and prolactin (PRL) affect reproduction and pregnancy; therefore, these two hormones influence fertility. This systematic review and meta-analysis aimed to summarise the strength of the correlation between serum PRL and thyroid stimulating hormone (TSH) in infertile women and to explore selected factors influencing the correlation. We conducted a systematic search of online databases (PubMed, Scopus, ScienceDirect, SAGE and Google Scholar) from inception until March 2021 and a manual search of the bibliographies of the included studies to identify relevant publications. The original research paper describing the correlation between PRL and TSH in reproductive-age women with infertility (primary and secondary) was included. The risk of bias was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Analytical Cross-Sectional Studies. A random effect model was used to estimate the pooled correlations of PRL and TSH, followed by an assessment of heterogeneity and a sensitivity analysis. From a total of 822 relevant articles identified, 11 were eligible and included in this systematic review and meta-analysis. The random effect pooled correlation estimates between PRL and TSH was 0.431 (95% CI: 0.251, 0.582), with substantial heterogeneity between the included studies (I2 = 80%, τ2 = 0.067, P < 0.001). No significant publication bias was observed. Study region, types of infertility, sample size and year of the study did not influence the correlation estimates. Our results highlighted a significant positive moderate correlation between serum PRL and serum TSH in infertile women.

Evaluation of a novel, sensitive thyroid-stimulating hormone assay as a diagnostic test for thyroid disease in cats.

Clinicians commonly use thyroid-stimulating hormone (TSH) concentrations to diagnose thyroid disorders in humans and dogs. In cats, canine TSH chemiluminescent immunoassays (CLIA) assays are commonly used to measure TSH, but these TSH-CLIAs cannot measure low TSH concentrations (< 0.03 ng/mL) and therefore cannot distinguish between low-normal concentrations and truly low TSH concentrations (characteristic of hyperthyroidism). Our aim was to evaluate a novel TSH assay based on bulk acoustic wave (BAW) technology that has lower functional sensitivity (0.008 ng/mL) than TSH-CLIAs. 169 untreated hyperthyroid cats, 53 cats treated with radioiodine (131I), 12 cats with chronic kidney disease (CKD), and 78 clinically healthy cats. Serum concentrations of T4, TSH-CLIA, and TSH-BAW were measured in all cats. Untreated hyperthyroid cats were divided into 4 severity groups (subclinical, mild, moderate, and severe), whereas 131I-treated cats were divided into euthyroid and hypothyroid groups. Test sensitivity, specificity, and positive predictive value for identifying hyperthyroidism were higher for TSH-BAW (90.5%, 98.9%, and 86.9%) than TSH-CLIA (79.9%, 76.7%, and 21.7%; P < .001). Test sensitivity for identifying 131I-induced hypothyroidism was only 45.5% for T4 versus 100.0% for both TSH-CLIA and TSH-BAW (P = .03), whereas TSH-BAW had a higher positive predictive value (100%) than did either TSH-CLIA (81.2%) or T4 (71.9%). Serum TSH-BAW alone or together with T4 is a highly sensitive and specific diagnostic test for evaluating feline hyperthyroidism and iatrogenic hypothyroidism. Finding low serum TSH-BAW concentrations is most useful for diagnosing subclinical and mild hyperthyroidism, in which serum T4 remains within or only slightly above the reference interval.

Association between TPO gene polymorphisms with susceptibility to hyperthyroidism

Introduction and Aim: Hyperthyroidism is a disorder characterized by excessively high amounts of tri-iodothyronine and thyroxine in the bloodstream. TPO is a thyroid-specific antigen. TPO gene mutations affect thyroid hormone synthesis, causing full or partial iodide organification abnormalities. In this study, we aimed to look at the single nucleotide polymorphisms (SNPs) in the TPO gene and find possible relation of these SNPs to the development or prognosis of hyperthyroidism. Materials and Methods: Blood samples were collected from hyperthyroid patients (n=75) and healthy individuals (n=25). The concentration of triiodothyronine (T3), Tetra-iodothyronine (T4), and thyroid stimulating hormone (TSH) were estimated in all samples. The autoantibodies TPOAbs and TR-Ab levels were measured using the ELISA assay. The extracted genomic DNA from blood of participants was investigated for polymorphism in the SNPs rs1126799, rs1126797, and rs732609 within the TPO gene. Statistical methods were used to evaluate the association between the TPO SNPs studied to hyperthyroidism susceptibility. Results: No significant correlation was observed between the SNPs studied and prognosis of hyperthyroidism. However, it was found that hyperthyroid patients carrying the TPO rs1126799 T allele (CT + CC genotypes) had significantly higher serum levels of TPOAb compared to those with the TT genotype (P&lt;0.01). Similarly, hyperthyroid patients with the TPO rs1126797 C allele (CT + TT genotypes) and TPO rs732609 A allele (CA + AA genotypes) exhibited significantly elevated levels of TPOAbs compared to individuals with the CC genotype and AA genotype, respectively (P&lt;0.01). Conclusion: There was no correlation between the TPO rs1126799, rs1126797, and rs732609 polymorphisms with the occurrence of hyperthyroidism in the Iraqi population. However, TPO rs2071400 and rs2048722 polymorphisms were found to be correlated to serum levels of TPOAb.

Association between Thyroid Function indices and Thyroid Autoantibodies with Thyroid Ultrasonography Outcomes in Children and Adolescents

Objectives: Thyroid Ultrasonography (US) is recommended as a valuable tool for evaluating the status and function of the thyroid gland. The objective of this study was to compare and analyze the thyroid ultrasonography outcomes in children and adolescents who have normal thyroid function and thyroid antibodies.&#x0D; Methods: A cross-sectional study was conducted on a group of 233 selected females aged 9 to 14 years old. Blood samples were obtained from the subjects and analyzed for thyroid hormones and thyroid autoantibodies. Additionally, a thyroid ultrasound was performed to provide an in-depth evaluation.&#x0D; Results: Of all the participants, 25% displayed hypoechogenicity. Individuals with reduced echogenicity had higher median levels of thyroid-stimulating hormone (TSH), thyroid peroxidase antibody (TPO-Ab), and thyroglobulin antibody (Tg-Ab) compared to those with normal echogenicity. Moreover, those with hypoechogenicity had significantly higher thyroid volume (TVol), iodine status, and thyroglobulin levels than their counterparts with normal echogenicity. Hypoechogenicity was also significantly associated with higher levels of TPO-Ab, Tg-Ab, and TSH. Logistic regression analysis revealed that high TSH and TPO-Ab levels were associated with a higher risk of irregular echo patterns and thyroid autoantibodies.&#x0D; Conclusion: The results revealed that irregular thyroid patterns in the ultrasonography were useful for assessing thyroid structure and dysfunction. Moreover, elevated TPOAb, Tg-Ab, and TSH concentrations in the serum may indicate thyroid malfunction. Ultrasound can help to identify early thyroid dysfunction along with the standard thyroid assessment biomarkers.

The association between dyslipidaemia in the first trimester and adverse pregnancy outcomes in pregnant women with subclinical hypothyroidism: a cohort study

BackgroundSubclinical hypothyroidism (SCH) is linked to dyslipidaemia and adverse pregnancy outcomes. However, the impact of dyslipidaemia on the outcome of pregnancy in SCH is unclear.MethodsWe enrolled 36,256 pregnant women and evaluated their pregnancy outcomes. The following data was gathered during the first trimester (≤ 13+ 6 weeks of gestation): total cholesterol (TC), low-density lipoprotein (LDL-C), triglyceride (TG), high-density lipoprotein (HDL-C), free thyroxine (FT4) and thyroid-stimulating hormone (TSH) concentrations. The reference ranges for lipids were estimated to range from the 5th to the 95th percentile. Logistic regression assessed the relationships between dyslipidaemia and adverse pregnancy outcomes, including abortion, preeclampsia/eclampsia, low birth weight, foetal growth restriction, premature rupture of foetal membranes, gestational hypertension, preterm birth, macrosomia and gestational diabetes mellitus (GDM). Additionally, the best thresholds for predicting adverse pregnancy outcomes based on TSH, FT4, and lipid levels were determined using receiver operating characteristic curves.ResultsIn the first trimester, LDL-C > 3.24 mmol/L, TG > 1.92 mmol/L, HDL-C < 1.06 mmol/L, and TC > 5.39 mmol/L were used to define dyslipidaemia. In this cohort, 952 (3.56%) patients were diagnosed with SCH, and those who had dyslipidaemia in the first trimester had higher incidences of gestational hypertension (6.59% vs. 3.25%), preeclampsia/eclampsia (7.14% vs. 3.12%), GDM (22.53% vs. 13.77%), and low birth weight (4.95% vs. 2.08%) than did those without dyslipidaemia. However, after adjusting for prepregnancy body mass index (pre-BMI), dyslipidaemia was no longer related to these risks. Furthermore, elevated TG dyslipidaemia in SCH patients was connected to an enhanced potential of gestational hypertension (odds ratio [OR]: 2.687, 95% confidence interval [CI]: 1.074 ~ 6.722), and elevated LDL-C dyslipidaemia correlated with increased preeclampsia/eclampsia risk (OR: 3.172, 95% CI: 1.204 ~ 8.355) after accounting for age, smoking status, alcohol use, pre-BMI, and levothyroxine use. Additionally, the combination of TC, TG, LDL-C, pre-BMI, and TSH exhibited enhanced predictive capabilities for gestational hypertension, preeclampsia/eclampsia, and GDM. Values of 0.767, 0.704, and 0.706 were obtained from the area under the curve.ConclusionsAmong pregnant women with SCH, dyslipidaemia in early pregnancy was related to elevated risks of adverse pregnancy consequences. The combined consideration of age, pre-BMI, TSH, and lipid levels in the first trimester could be beneficial for monitoring patients and implementing interventions to reduce adverse pregnancy outcomes.

Morphofunctional and psychophysiological body indicators in monitoring students’ health status, in view of their adjustment to academic environment

Students’ adjustment to higher education process depends largely on the body’s individual features. The student’s physiological and psychological status, as well as the initial motivational setting attitudes are the determining factors. Given this backcloth, the search for ways to improve the health, while aiming at enhancing future qualified specialists’ working and adjustment capacity, appears to be an issue of utmost importance.Material and methods. A longitudinal study involving university students of different years was carried out, through which anthropometric data were evaluated for the same students in their 1st year and then – in their 2nd year of training; the concentration of testosterone and cortisol in saliva, thyroid-stimulating hormone and triiodothyronine in blood serum was measured by ELISA; also, psychophysiological values were estimated through unified questionnaires.Results. The results showed that over the course of education, the students had their hemoglobin concentration, average hemoglobin content in erythrocytes, and leukocyte number decreased. Notable was a significant increase in 3rd year students’ thyroid-stimulating hormone content and a decrease of triiodothyronine and testosterone. A test relying on the Buss – Durkee Hostility Inventory helped to detect an increase in the aggression and suspicion criterion indicators among senior students if matched versus similar values obtained for their freshmen-counterparts.Conclusions. The research outcomes expand the informational and the methodological base required to evaluate an average student’s functional status from the standpoint of a systematic approach and the theory of the norm. Besides, such data will offer an insight into the main mechanisms behind stressinducing, just like stress-limiting, adjustment strategies. This study of the morphofunctional status indicators allows – while within the annual health monitoring approach – identifying the regulatory and the adjustment capacities in students, both at the time they are enrolled as freshmen and further, thus helping predict the potential risk of maladjustment, which, in turn, may serve a useful tool in taking preventive measures, the final goal being to maintain students’ health through their higher education training period.

Role of thyroid stimulating hormone in the maintenance and functioning of the human corpus luteum.

To evaluate the impact of high thyroid stimulating hormone (TSH) levels on human granulosa-luteal (hGL) cells. hGL cells were isolated from follicular aspirates derived from patients undergoing IVF treatment without any thyroid disorder (serum TSH 0.5-2mU/L). Cells were cultured at 37°C in DMEM, supplemented with 5% FBS. The cells were treated with 1nM LH and increasing concentrations of TSH. At the end of culture, conditioned medium and cells were collected to analyze progesterone production, cell viability, and mRNA levels of genes involved in the steroidogenesis process. Human ovarian tissues were analyzed for TSH receptor (TSHR) expression by IHC. The expression of TSHR was detected in human corpus luteum by IHC and in hGL by RT-PCR. In hGL cells, TSH treatment did not modulate progesterone production nor the expression of steroidogenic genes, such as p450scc and HSD3b 1/2. However, TSH induced a dose-dependent increase in cell death. Finally, TSH did not affect LH-induced p450scc and HSD3b1/2 expression while LH partially reverted TSH negative effect on cell death in hGL. Elevated TSH levels in hypothyroid women may be associated with impaired CL functioning and maintenance. These findings open a new line of research for the importance of the treatment of women with thyroid dysfunction that could contribute to the onset of infertility.

The Predictive Value of Conventional Ultrasound Signs Plus Serological Indices for Neck Lymph Node Metastasis in Papillary Thyroid Cancer

The present study aimed to evaluate the predictive value of conventional ultrasound signs and serological indices in the detection of neck lymph node metastasis in papillary thyroid cancer (PTC). A total of 80 patients with PTC scheduled for surgery in our hospital between August 2019 and December 2022 were recruited. Patients with neck lymph node metastasis were categorized as the experimental group, and patients without neck lymph node metastasis were included in the control group. Patients’ ultrasound signs were analyzed, and serological indices were determined. Logistic analysis was performed to determine the risk factors for the development of postoperative neck lymph node metastasis in papillary thyroid cancer, and the receiver operating characteristic (ROC) curve was employed to assess their diagnostic efficiency. Significant differences were observed in the number of lesions, nodule size, calcification, blood flow RI, and PI values comparison between the two arms (P &lt; 0.05), while no significant differences were found in other ultrasound signs (P &gt; 0.05). Patients with neck lymph node metastasis exhibited significantly higher serum concentrations of thyroid stimulating hormone (TSH) and anti-thyroglobulin antibodies (TG-Ab) versus those without metastasis (P &lt; 0.05). Nodule size, number of lesions, and serum TSH level were independent risk factors for metastasis in neck lymph nodes in patients with papillary thyroid cancer (P &lt;0.05). Conventional ultrasound signs, combined with serologic indices, demonstrated the highest diagnostic efficiency for predicting neck lymph node metastasis in patients with papillary thyroid cancer. These findings showed a sensitivity of 0.868, specificity of 0.894, and an area under the ROC curve (AUC) of 0.918. Additionally, the Jorden index was calculated to be 0.761. Analysis revealed that nodule size, number of lesions, and serum TSH concentration were independent risk factors for neck lymph node metastasis in papillary thyroid cancer patients. The combination of conventional ultrasound signs and serologic indices provided a higher diagnostic value compared to using a single diagnostic modality, thus indicating promising clinical benefits.

Development and internal validation of diagnostic prediction models using machine-learning algorithms in dogs with hypothyroidism.

Hypothyroidism can be easily misdiagnosed in dogs, and prediction models can support clinical decision-making, avoiding unnecessary testing and treatment. The aim of this study is to develop and internally validate diagnostic prediction models for hypothyroidism in dogs by applying machine-learning algorithms. A single-institutional cross-sectional study was designed searching the electronic database of a Veterinary Teaching Hospital for dogs tested for hypothyroidism. Hypothyroidism was diagnosed based on suggestive clinical signs and thyroid function tests. Dogs were excluded if medical records were incomplete or a definitive diagnosis was lacking. Predictors identified after data processing were dermatological signs, alopecia, lethargy, hematocrit, serum concentrations of cholesterol, creatinine, total thyroxine (tT4), and thyrotropin (cTSH). Four models were created by combining clinical signs and clinicopathological variables expressed as quantitative (models 1 and 2) and qualitative variables (models 3 and 4). Models 2 and 4 included tT4 and cTSH, models 1 and 3 did not. Six different algorithms were applied to each model. Internal validation was performed using a 10-fold cross-validation. Apparent performance was evaluated by calculating the area under the receiver operating characteristic curve (AUROC). Eighty-two hypothyroid and 233 euthyroid client-owned dogs were included. The best performing algorithms were naive Bayes in model 1 (AUROC = 0.85; 95% confidence interval [CI] = 0.83-0.86) and in model 2 (AUROC = 0.98; 95% CI = 0.97-0.99), logistic regression in model 3 (AUROC = 0.88; 95% CI = 0.86-0.89), and random forest in model 4 (AUROC = 0.99; 95% CI = 0.98-0.99). Positive predictive value was 0.76, 0.84, 0.93, and 0.97 in model 1, 2, 3, and 4, respectively. Negative predictive value was 0.89, 0.89, 0.99, and 0.99 in model 1, 2, 3, and 4, respectively. Machine learning-based prediction models were accurate in predicting and quantifying the likelihood of hypothyroidism in dogs based on internal validation performed in a single-institution, but external validation is required to support the clinical applicability of these models.

Relationship between thyroid function and sex hormones in female German shepherd dogs.

Several variables influence the serum concentration of thyroid hormones in dogs, including breed, age, drugs, and concurrent diseases. However, data regarding the interaction between thyroid function and the estrous stage of female dogs are limited. Estrous stage may influence thyroid function in German Shepherd dogs. Longitudinal, observational, non-randomized cohort study. The dogs were monitored during the complete estrous cycle, and different stages were determined by vaginal cytology. Two blood samples were collected at the beginning and end of each stage to analyze the following: total thyroxine (TT4), free thyroxine (fT4), total triiodothyronine (TT3), free triiodothyronine (fT3), canine thyrotropin (cTSH), progesterone, 17-β-estradiol, triglycerides, and cholesterol concentrations. Hematological and biochemical evaluations were performed at the beginning and end of the study period. Seventeen German Shepherds were included, of which 7 were bred during the study period. One dog was excluded for estrus interruption and another for suspected hypothyroidism. Serum concentrations of T4, fT4, and fT3 were negatively correlated with age. Total thyroxine demonstrated significant changes in serum concentrations between estrous stages, with higher concentrations in estrus and diestrus. Total thyroxine concentrations were positively correlated with progesterone concentrations and negatively correlated with 17-β-estradiol concentrations. Free thyroxine did not show significant variations but was positively correlated with progesterone concentrations. Canine TSH concentrations were positively correlated with 17-β-estradiol concentrations. No significant differences in thyroid hormones and cTSH concentrations were observed between diestrus during pregnancy and pseudopregnancy. Different stages of estrus can influence the measurement of TT4 in female dogs.

Thyroid disfunction and chronic obstructive pulmonary disease: case report

Common concomitant endocrine diseases in chronic obstructive pulmonary disease (COPD) patients include both structural and functional lesions of the thyroid gland.The purpose of the study was to determine specific indicators for the differential diagnosis of thyroid storm and exacerbation of COPD. A clinical observation of a 60-year-old patient who received inpatient treatment in the therapeutic department of a city clinical hospital is presented. The diagnosis upon admission was COPD, mixed form, severe, exacerbation, and respiratory failure of the first degree.Results. In the hospital, the patient experienced an episode of difficulty breathing lasting 45 minutes. Increased shortness of breath alternated with normal breathing and was accompanied by tremor of the hands. The patient was agitated, refused to breathe oxygen through the mask, and was in orthopnea. The patient’s condition during the attack was assessed at 40 points according to the Burch – Wartofsky scale, which corresponds to a high probability of thyroid storm (TS). Pronounced ventilation disturbances of a mixed type were recorded based on the spirography results (forced expiratory volume in 1 second – 19%). Echocardiography revealed no signs of cor pulmonale or pulmonary hypertension. A low concentration of thyroid-stimulating hormone was recorded, the level of free thyroxine (T4) remained within the reference range. Serum levels of thyroid peroxidase antibodies did not increase, and no changes in the thyroid gland were detected during ultrasound examination.Conclusion. When thyroid abnormality manifests in a patient with COPD, certain difficulties may arise with the differential diagnosis of exacerbation of COPD and TS due to the similarity of their clinical manifestations.

The negative impact of levothyroxine treatment on urinary luteinizing hormone measurements in pediatric patients with thyroid disease.

Previous studies suggest urinary luteinizing hormone (LH) and follicle-stimulating hormone (FSH) measurements by immunofluorometric assays (IFMA) as noninvasive alternatives to serum assays for puberty assessment. However, these studies excluded patients with other endocrine disorders and those taking medications. Besides, the recent discontinuation of IFMA manufacturing is a concern. We explored the utility of luminometric assays (LIA) for urinary gonadotropins and thyroid-stimulating hormone (TSH) determinations in euthyroid patients with thyroid pathologies. We used LIA and IFMA assays to measure serum and first-morning-voided (FMV) urine LH, FSH, and TSH concentrations in euthyroid patients with various thyroid disorders. Of the 47 euthyroid patients with normal serum TSH (S-TSH) levels, 14 were receiving levothyroxine therapy. FMV total urinary LH (U-LH) concentrations correlated significantly with those measured in serum using either LIA (r=0.67, P<.001) or IFMA (r=0.83, P=.003) in patients not receiving levothyroxine treatment; however, no significant correlation could be detected in patients receiving levothyroxine regardless of the assay method (for LIA: r=0.50, P=.08 and IFMA r=0.44, P=.15). Urinary TSH (U-TSH) concentrations correlated poorly with those in serum in both the untreated and the treated groups (r=-0.13, P=.49, and r=-0.45, P=.11, respectively). FMV total U-LH determinations by LIA can be used to assess pubertal development in patients with thyroid pathology, provided the euthyroid patient is not on levothyroxine treatment. U-TSH measurements by LIA cannot replace invasive S-TSH measurements at least in patients with normal S-TSH levels. Further research may reveal the utility of U-TSH determinations in patients with elevated S-TSH levels.

Changes in thyroid function and evolution of subclinical thyroid disease in older men.

Prevalence of subclinical thyroid disease increases with age, but optimal detection and surveillance strategies remain unclear particularly for older men. We aimed to assess thyroid stimulating hormone (TSH) and free thyroxine (FT4) concentrations and their longitudinal changes, to determine the prevalence and incidence of subclinical thyroid dysfunction in older men. Longitudinal study of 994 community-dwelling men aged ≥70 years without known or current thyroid disease, with TSH and FT4 concentrations assessed at baseline and follow-up (after 8.7 ± 0.9 years). Factors associated with incident subclinical thyroid dysfunction were examined by logistic regression and receiver operating characteristic analyses. At baseline, 85 men (8.6%) had subclinical hypothyroidism and 10 (1.0%) subclinical hyperthyroidism. Among 899 men euthyroid at baseline (mean age 75.0 ± 3.0 years), 713 (79.3%) remained euthyroid, 180 (20.0%) developed subclinical/overt hypothyroidism, and 6 (0.7%) subclinical/overt hyperthyroidism. Change in TSH correlated with baseline TSH (r = .16, p < .05). Change in FT4 correlated inversely with baseline FT4 (r = -0.35, p < .05). Only higher age and baseline TSH predicted progression from euthyroid to subclinical/overt hypothyroidism (fully-adjusted odds ratio [OR] per year=1.09, 95% confidence interval [CI] = 1.02-1.17, p = .006; per 2.7-fold increase in TSH OR = 65.4, CI = 31.9-134, p < .001). Baseline TSH concentration ≥2.34 mIU/L had 76% sensitivity and 77% specificity for predicting development of subclinical/overt hypothyroidism. In older men TSH concentration increased over time, while FT4 concentration showed little change. Subclinical or overt hypothyroidism evolved in one fifth of initially euthyroid men, age and higher baseline TSH predicted this outcome. Increased surveillance for thyroid dysfunction may be justified in older men, especially those with high-normal TSH.

Thyroglobulin as a Sensitive Biomarker of Iodine Status in Mildly and Moderately Iodine-Deficient Pregnant Women

Pregnant women are more susceptible to iodine deficiency. However, there are limitations in existing indicators for the evaluation of iodine nutrition in pregnant women. The study aimed to explore whether thyroglobulin (Tg) can be used as a more sensitive biomarker for pregnant women with mild and moderate iodine deficiency. A repeated-measure study was conducted among 1332 pregnant women in Zhejiang Province, China. Serum and urine specimens were collected at a mean of 10, 17, and 32 weeks of pregnancy, respectively; thyroid-stimulating hormone (TSH), Tg, and urinary iodine concentrations were measured. Linear mixed effects models were used to determine the associations between interaction of iodine concentrations and increasing gestation week and TSH and Tg, where participants were divided by urinary iodine concentration (UIC). The median Tg concentration was 11.56, 11.45, and 12.43 μg/L in the first, second, and third trimesters, respectively. After controlling the covariates, the interaction effects between the iodine status and gestation week were significant for both TSH and Tg (p = 0.038 and p = 0.007, respectively). TSH increased with the week of gestation in both iodine concentration groups. Tg increased with advancing pregnancy in the iodine-deficient group whereas it did not in the iodine-sufficient group. There was no significant variation in TSH at each trimester, and Tg was higher in the iodine-deficient group than in the iodine-sufficient group. Tg may be a more sensitive iodine status biomarker than TSH for pregnant women with mild-to-moderate iodine insufficiency.

The correlation between iron deficiency anemia and hypothyroidism during pregnancy

Abstract Background: Pregnant women are often iron deficient, and this has adverse effects on thyroid metabolism. Impaired maternal thyroid function in pregnancy may cause neurodevelopmental delay in the offspring. Objectives: To investigate if maternal iron status is a determinant of thyroid stimulating hormone (TSH) and/or free T4 (FT4) concentrations during pregnancy. Materials and Methods: A case–control study was conducted in the Department of Obstetrics and Gynecology at Azadi Teaching Hospital, Kirkuk, Iraq over a period of 7 months from February 1st to September 1st, 2020. It included 80 pregnant women with singleton pregnancy in the obstetric outpatient clinic and labor room. Verbal consent was obtained. They were divided into: (1) case group: it included 40 cases of iron deficiency (ID) anemic pregnant women with hemoglobin level of 105 g/L and less in the second and third trimesters. (2) Control group: It included 40 cases of healthy pregnant women. Estimation of gestational age was done depending on the date of last menstrual cycle, and/or early ultrasound scan. Results: In this study, 80 pregnant women in their second and third trimesters participated. Fifty percent were anemic, had elevated serum soluble transferrin receptor and negative body iron stores, 35% had a free T4 less than 7.5 pmol/L, and 47.5% had a TSH more than 4.0 mIU/L. 47.5% who were hypothyroid had negative body iron store. Serum ferritin, soluble transferrin receptor, and body iron stores were highly significant predictors of thyroid status. Conclusions: Poor maternal iron status predicts both higher TSH and lower free T4 concentrations during pregnancy. On the basis of results, we had there may be a correlation between ID anemia of pregnant women and their thyroid status.

Changes in thyroid function levels in female patients with first-episode bipolar disorder.

The identification of molecular biomarkers for bipolar disorder is anticipated to greatly improve the diagnosis and treatment of this disease. The objective of this case-control study is to determine whether the blood thyroid hormone levels in bipolar disorder patients are associated with different types of first onset. From August 1, 2020 to July 31, 2021 a total of 120 female patients diagnosed with bipolar disorder and hospitalized at Qingdao Mental Health Center were recruited as the case group, including 60 patients with depression as their first onset (depression first-episode group, DF) and 60 with mania/hypomania as their first onset (mania/hypomania first-episode group, M/HF). A group of 60 healthy adult females matching general demographic data, such as race and age, were selected as the control group. Blood samples were taken from both groups to measure serum triiodothyronine (T3), thyroxine (T4), free triiodothyronine (FT3), free thyroxine (FT4), and thyroid stimulating hormone (TSH) concentrations. The duration of current onset in the M/HF group was significantly less than that in the DF group (23.1 ± 20.2 vs. 125.2 ± 41.0 days). About 27% of patients in the M/HF group had thyroid abnormalities, in contrast to 60% in the DF group. The blood T3 and T4 levels in both the M/HF group and the DF group, as well as the TF3 levels in the DF group, were significantly lower as compared to control. The M/HF group had significantly higher T3 and FT3 levels than the DF group. The blood T3 levels were inversely correlated with the Young's Mania Scale score and the Hamilton Depression Scale score in both the M/HF and DF groups. Thyroid dysfunction resulting in reduced levels of blood thyroid levels may be involved in the disease progression of bipolar disorder, and correlated with the clinical symptoms in patients with depression or mania as the first episode.

The effect of metformin therapy on serum thyrotropin and free thyroxine concentrations in patients with type 2 diabetes: a meta-analysis

Type 2 diabetes and thyroid function disorders are two common chronic endocrine disorders with the high prevalence in various populations. Metformin is well established as the first-line drug therapy for managing diabetes mellitus. In this meta-analysis, we aimed to determine the effect of metformin on serum TSH and FT4 concentrations in patients with type 2 diabetes. We searched PubMed, Scopus, web of science, Cochrane library, and google scholar to collect information on the effect of metformin on serum TSH and FT4 levels. Demographic and clinical information and serum TSH and FT4 concentrations before and after metformin treatment were extracted. Studies on patients over 18 years of age were included. A total of 11 studies including 1147 patients were selected for the final analysis. In hypothyroid patients, the TSH level decreased significantly after treatment with metformin (Hedges’s g:1.55, 95%CI 0.93–2.16, p-value < 0.001); FT4 level increased slightly after taking metformin, but the increase was not significant (Heddges’s g: − 0.30, 95%CI − 0.90,0.31, p-value = 0.34). In euthyroid subjects, the slight decrease found in TSH and FT4 concentrations was not statistically significant. Metformin reduces TSH levels in hypothyroid patients; however, it has no effect on TSH levels in euthyroid patients. Metformin does not affect serum FT4 levels in euthyroid and hypothyroid patients.

Towards translating in vitro measures of thyroid hormone system disruption to in vivo responses in the pregnant rat via a biologically based dose response (BBDR) model

Despite the number of in vitro assays that have been recently developed to identify chemicals that interfere with the hypothalamic-pituitary-thyroid axis (HPT), the translation of those in vitro results into in vivo responses (in vitro to in vivo extrapolation, IVIVE) has received limited attention from the modeling community. To help advance this field a steady state biologically based dose response (BBDR) model for the HPT axis was constructed for the pregnant rat on gestation day (GD) 20. The BBDR HPT axis model predicts plasma levels of thyroid stimulating hormone (TSH) and the thyroid hormones, thyroxine (T4) and triiodothyronine (T3). Thyroid hormones are important for normal growth and development of the fetus. Perchlorate, a potent inhibitor of thyroidal uptake of iodide by the sodium iodide symporter (NIS) protein, was used as a case study for the BBDR HPT axis model. The inhibitory blocking of the NIS by perchlorate was associated with dose-dependent steady state decreases in thyroid hormone production in the thyroid gland. The BBDR HPT axis model predictions for TSH, T3, and T4 plasma concentrations in pregnant Sprague Dawley (SD) rats were within 2-fold of observations for drinking water perchlorate exposures ranging from 10 to 30,000 μg/kg/d. In Long Evans (LE) pregnant rats, for both control and perchlorate drinking water exposures, ranging from 85 to 82,000 μg/kg/d, plasma thyroid hormone and TSH concentrations were predicted within 2 to 3.4- fold of observations. This BBDR HPT axis model provides a successful IVIVE template for thyroid hormone disruption in pregnant rats.

Alterations in serum concentrations of visfatin and betatrophin in dogs with hypothyroidism.

Hypothyroidism in dogs is associated with obesity and altered lipid and carbohydrate metabolism. The adipokines, visfatin, and betatrophin, affect glucose tolerance. Betatrophin is involved in lipid regulation. Visfatin and betatrophin serum concentrations are altered in hypothyroid dogs. Dogs with naturally occurring hypothyroidism (n = 25) and healthy dogs (n = 25). Insulin, visfatin, and betatrophin serum concentrations were measured in all dogs and 19 of the hypothyroid dogs after 30 days of thyroxine treatment. Body condition score (BCS) was determined (1-9 scale). Visfatin concentrations were lower in hypothyroid compared with healthy dogs (mean, 95% confidence interval [CI]; 2.0 ng/mL, 1.2-3.3 vs 5.1 ng/mL, 3.3-7.8; P = .004) and increased post-treatment (3.1 ng/mL, 1.9-4.9 vs 2.6 ng/mL, 1.6-4.1; P = .05). Betatrophin concentrations were lower in lean to normal (body condition score [BCS], 3-5) hypothyroid dogs compared to lean to normal healthy dogs (52 pg/mL, 9-307 vs 597 pg/mL, 216-1648; P = .03), but were not different between overweight (BCS, 6-9) hypothyroid and healthy dogs (341 pg/L, 168-695 vs 178 pg/mL, 77-415; P = .26), and decreased post-treatment in overweight dogs (206 pg/mL, 87-488 vs 268 pg/mL, 112-640; P = .004). Visfatin concentrations were higher in overweight compared with lean to normal dogs (4.7 ng/mL, 3.3-6.6 vs 2.2 ng/mL, 1.2-4.2; P = .04). Betatrophin concentrations were positively correlated with BCS (r = .47, P = .02) and insulin concentrations (r = .48, P = .03) in hypothyroid dogs and negatively correlated with BCS (r = -.47, P = .02) and thyroid stimulating hormone concentrations (r = -.56, P = .01) in healthy dogs. Hypothyroidism in dogs is associated with alterations in visfatin and betatrophin concentrations that partially resolve with thyroxine treatment.