scholarly journals The Influence of Age and Sex on Tests of Thyroid Function

1985 ◽  
Vol 22 (5) ◽  
pp. 502-505 ◽  
Author(s):  
J A Franklyn ◽  
D B Ramsden ◽  
M C Sheppard
Keyword(s):  
Thyroid Hormone ◽  
Thyroid Hormones ◽  
Thyroid Function ◽  
Normal Subjects ◽  
Thyroid Stimulating Hormone ◽  
Free T4 ◽  
Reverse T3 ◽  
Free Thyroid Hormones ◽  
Free T3 ◽  
Age And Sex

Serum concentrations of total thyroid hormones, thyroid hormone binding proteins, free thyroid hormones and thyroid stimulating hormone (TSH) were measured in a large group of healthy normal subjects ( n = 218) to determine the influence of age and sex on tests of thyroid function. No effect of age on measurements of total thyroxine (T4), total triiodothyronine (T3) or reverse T3 was evident. Concentrations of free T4, free T3 and TSH were similarly unaffected, suggesting that increasing age alone does not significantly influence thyroid hormone measurements. There was, however, a rise in thyroxine-binding globulin (TBG) concentration with increasing age and a fall in thyroxine-binding prealbumin (TBPA). An influence of sex on tests of thyroid function was clearly evident. Levels of total T4, total T3, free T4 and the T4: TBG ratio were lower in women between 16 and 49 years than in men, despite an increase in TBG. Lower levels of free T3 were confined to the group of women aged 16–29 years. TSH values were unaffected by sex. These results suggest that sex hormone status in the pre-menopausal female subject may result in an increase in TBG concentration, and in addition may have an opposing effect on circulating thyroid hormone concentrations.

Iodide Metabolism and Effects

2020 ◽  
pp. 25-33
Keyword(s):  
Thyroid Hormone ◽  
Thyroid Gland ◽  
Thyroid Hormones ◽  
Dietary Supplement ◽  
Thyroid Function ◽  
Thyroid Stimulating Hormone ◽  
Hormone Synthesis ◽  
Serum Tsh ◽  
Tsh Stimulation ◽  
Sensitive Marker

Iodine (I2) is essential in the synthesis of thyroid hormones T4 and T3 and functioning of the thyroid gland. Both T3 and T4 are metabolically active, but T3 is four times more potent than T4. Our body contains 20-30 mg of I2, which is mainly stored in the thyroid gland. Iodine is naturally present in some foods, added to others, and available as a dietary supplement. Serum thyroid stimulating hormone (TSH) level is a sensitive marker of thyroid function. Serum TSH is increased in hypothyroidism as in Hashimoto's thyroiditis. In addition to regulation of thyroid function, TSH promotes thyroid growth. If thyroid hormone synthesis is chronically impaired, TSH stimulation eventually may lead to the development of a goiter. This chapter explores the iodide metabolism and effects of Hashimoto's disease.

Screening for New Markers to Assess Thyroid Hormone Action by OMICs Analysis of Human Samples

2020 ◽  
Vol 128 (06/07) ◽  
pp. 479-487 ◽  
Author(s):  
Nele Friedrich ◽  
Maik Pietzner ◽  
Beatrice Engelmann ◽  
Georg Homuth ◽  
Dagmar Führer ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Thyroid Function ◽  
Clinical Symptoms ◽  
Pituitary Tumors ◽  
Population Based ◽  
Thyroid Stimulating Hormone ◽  
Central Hypothyroidism ◽  
Free Thyroid Hormones ◽  
Molecular Alterations ◽  
Novel Biomarkers

ABSTRACTDetermination of the levels of thyroid-stimulating hormone (TSH) and free thyroid hormones (fTHs) is crucial for assessing thyroid function. However, as a result of inter-individual genetic variability and different environmental factors individual set points exist for TSH and fTHs and display considerable variation. Furthermore, under specific pathophysiological conditions like central hypothyroidism, TSH secreting pituitary tumors, or thyroid hormone resistance the established markers TSH and fTH fail to reliably predict thyroid function and adequate supply of TH to peripheral organs. Even in case of overt hyper- and hypothyroidism circulating fTH concentrations do not correlate with clinical symptoms. Therefore, there is a clear need for novel, more specific biomarkers to diagnose and monitor thyroid function. OMICs screening approaches allow parallel profiling of hundreds to thousands of molecules and thus comprehensive monitoring of molecular alterations in tissues and body fluids that might be associated with changes in thyroid function. These techniques thus constitute promising tools for the identification of urgently needed novel biomarkers. This mini review summarizes the findings of OMICs studies in thyroid research with a particular focus on population-based and patient studies as well as interventional approaches investigating the effects of thyroid hormone administration.

scholarly journals Correlations of Free Thyroid Hormones Measured by Tandem Mass Spectrometry and Immunoassay with Thyroid-Stimulating Hormone across 4 Patient Populations

2009 ◽  
Vol 55 (7) ◽  
pp. 1380-1388 ◽  
Author(s):  
Jacqueline Jonklaas ◽  
Natasa Kahric-Janicic ◽  
Offie P Soldin ◽  
Steven J Soldin
Keyword(s):  
Mass Spectrometry ◽  
Thyroid Hormone ◽  
Tandem Mass Spectrometry ◽  
Thyroid Hormones ◽  
Thyroid Stimulating Hormone ◽  
Free Thyroxine ◽  
Tandem Mass ◽  
Free Triiodothyronine ◽  
Free Thyroid Hormones ◽  
Free Thyroid Hormone

Abstract Background: Accurate measurement of free thyroid hormones is important for managing thyroid disorders. Ultrafiltration liquid chromatography tandem mass spectrometry (LC-MS/MS) can reliably measure the concentrations of small molecules, including thyroid hormones. Our study was designed to compare free thyroid hormone measurements performed with immunoassay and LC-MS/MS. Methods: We studied the performance of LC-MS/MS in 4 different populations comprising pediatric patients, euthyroid adults, and healthy nonpregnant and pregnant women. The samples obtained from each population numbered 38, 200, 28, and 128, respectively. Free thyroxine, free triiodothyronine, and thyroid-stimulating hormone (TSH) concentrations were documented. Results: LC-MS/MS measurement of free thyroid hormones provided better correlation with log-transformed serum TSH in each population and also the populations combined. The correlations between free thyroxine measured by LC-MS/MS and log TSH in the pediatric outpatients and healthy adults were −0.90 and −0.77, respectively. The correlations for immunoassay were −0.82 and −0.48. The correlations between free triiodothyronine measured by LC-MS/MS and TSH for both pediatric and healthy adult populations were −0.72 and −0.68, respectively. Conclusions: Free thyroid hormone concentrations measured by LC-MS/MS correlate to a greater degree with log TSH values compared to concentrations measured by immunoassay. This correlation was maintained across the patient populations we studied and may reflect the accuracy and specificity of LC-MS/MS. The superior ability of LC-MS/MS to enable documentation of the well-known thyroid hormone–TSH relationship supports the use of this measurement technique in a variety of clinical situations.

THYROID PROFILE IN CHILDREN WITH NEPHROTIC SYNDROME

2021 ◽  
pp. 75-77
Author(s):  
Meiyappan Kavitha ◽  
Mallaiyan Manonmani
Keyword(s):  
Nephrotic Syndrome ◽  
Thyroid Hormone ◽  
Thyroid Hormones ◽  
Thyroid Stimulating Hormone ◽  
The Body ◽  
Urinary Protein ◽  
Creatinine Ratio ◽  
Free Triiodothyronine ◽  
Free T4 ◽  
Renal Disorder

Objectives: Nephrotic syndrome is a common renal disorder seen in children, with proteinuria as the hallmark. Growth retardation is a known feature of nephrotic syndrome, either due to the disease or treatment with steroids. Thyroid hormone strongly inuences growth of the body. So, the present study was undertaken with the objective to assess the thyroid prole in children with nephrotic syndrome Methods: The study involved 41 cases of nephrotic syndrome and 41 age and sex matched controls. Serum total triiodothyronine (T3), total thyroxine (T4), free triiodothyronine (T3), free thyroxine (T4) and thyroid stimulating hormone (TSH) were assessed in these subjects. The thyroid hormones were correlated with urinary protein creatinine ratio. The cases were followed up after one month and the levels of thyroid hormones were reassessed. Results: Total T3, total T4, free T3 and free T4 are signicantly decreased and TSH signicantly increased among cases when compared to controls. TSH is positively correlating with urinary protein creatinine ratio in cases. After one month of treatment, total T3 and total T4 are signicantly increased in cases. Conclusions: The thyroid hormone levels are altered in children with nephrotic syndrome during the episode. A state of subclinical hypothyroidism exists during the nephrotic stage. The alteration is normalized with remission and does not require treatment.

scholarly journals Combined effects of cadmium and decabrominated diphenyl ether on thyroid hormones in rats

2012 ◽  
Vol 63 (3) ◽  
pp. 255-262 ◽  
Author(s):  
Marijana Ćurčić ◽  
Saša Janković ◽  
Vesna Jaćević ◽  
Sanja Stanković ◽  
Slavica Vučinić ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Thyroid Hormones ◽  
Thyroid Function ◽  
Wistar Rats ◽  
Diphenyl Ether ◽  
Thyroid Stimulating Hormone ◽  
Combined Effects ◽  
Single Substance ◽  
Hormone Homeostasis ◽  
Stimulating Hormone

The aim of this study was to see how a mixture of cadmium (Cd) and decabrominated diphenyl ether (BDE209) affect thyroid function, namely thyroid-stimulating hormone (TSH), thyroxin (T4), free thyroxin (FT4), triiodothyronin (T3), and free triiodothyronin (FT3) in Wistar rats (eight per group) receiving either a single substance or their combination by gavage for 28 days. Three groups were receiving Cd alone in the doses of 2.5 mg kg-1, 7.5 mg kg-1, or 15 mg kg-1 b. w. a day, three groups were receiving BDE209 in the doses of 1000 mg kg-1, 2000 mg kg-1, or 4000 mg kg-1 b. w. a day, while nine groups were receiving different mixtures of Cd and BDE209 in these doses (3x3 design). The results have indicated that the Cd+BDE209 mixtures more potently disrupt thyroid hormone homeostasis than would be expected from these chemicals alone.

Prevalence of thyroid dysfunction and effect of contrast medium on thyroid metabolism in cardiac patients undergoing coronary angiography

2013 ◽  
Vol 54 (1) ◽  
pp. 42-47 ◽  
Author(s):  
Paolo Marraccini ◽  
Massimiliano Bianchi ◽  
Antonio Bottoni ◽  
Alessandro Mazzarisi ◽  
Michele Coceani ◽  
...  
Keyword(s):  
Coronary Angiography ◽  
Contrast Medium ◽  
Thyroid Function ◽  
Thyroid Dysfunction ◽  
Thyroid Stimulating Hormone ◽  
Low T3 Syndrome ◽  
Free T4 ◽  
Free T3 ◽  
Iodinated Contrast ◽  
Low T3

Background Iodinated contrast media (CM) may influence thyroid function. Precautions are generally taken in patients with hyperthyroidism, even if subclinical, whereas the risks in patients with hypothyroidism or low triiodothyronine (T3) syndrome are not considered as appreciable. Purpose To assess the presence and type of thyroid dysfunction in patients admitted for coronary angiography (CA), to assess the concentration of free-iodide in five non-ionic CM, and to evaluate changes in thyroid function after CA in patients with low T3 syndrome. Material and Methods We measured free T3, free thyroxine (T4), and thyroid-stimulating hormone (TSH) in 1752 consecutive patients prior to CA and free-iodide in five non-ionic CM. Urinary free-iodide before and 24 h after CA, and thyroid hormone profile 48 h after CA were also made in 17 patients with low T3 syndrome. Patients were followed up for an average duration of 63.5 months. Results The patients were divided into four groups: euthyroidism (60%), low T3 syndrome (28%), hypothyroidism (10%), and hyperthyroidism (2%). The free-iodide resulted far below the recommended limit of 50 μg/mL in all tested CM. In low T3 syndrome, 24-h free-iodide increased after CA from 99.9± 63 ug to 12276±9285 ug (P< 0.0001). A reduction in TSH (4.97±1.1 vs. 4.17±1.1 mUI/mL, P < 0.01) and free T3 (1.44±0.2 vs. 1.25±0.3 pg/mL, P < 0.01), with an increase in free T4 (11.3±2.9 vs. 12.5±3.4 pg/dL, P < 0.001), was found. Patients with functional thyroid disease in the follow-up had a significant lower rate survival compared to euthyroid patients (90.7 vs. 82.2%, P < 0.00001). Conclusion Thyroid dysfunction is frequent in patients who perform a CA, and low T3 syndrome is the predominant feature. The administration of contrast medium may further compromise the thyroid function.

scholarly journals Thyroid hormone resistance syndrom: difficulties in differential diagnosis

2018 ◽  
Vol 14 (1) ◽  
pp. 39-46
Author(s):  
Lyudmila A. Ruyatkina ◽  
Aguniya A. Molchanova ◽  
Alina S. Ruyatkina ◽  
Lyudmila Y. Rozhinskaya
Keyword(s):  
Differential Diagnosis ◽  
Thyroid Hormone ◽  
Thyroid Hormones ◽  
Thyroid Hormone Receptor ◽  
Signs And Symptoms ◽  
Thyroid Stimulating Hormone ◽  
Heterozygous Mutation ◽  
Hormone Resistance ◽  
Thyroid Hormone Resistance ◽  
Free Thyroid Hormones

Thyroid hormone resistance syndrome (RTH) is a rare disorder characterized by reduced peripheral tissue responses to thyroid hormones (TH) and elevated levels of circulating free thyroid hormones. Resistance to thyroid hormone is caused by mutations of the thyroid hormone receptor beta (THRB) gene. In this article, we present case of 26-years-old women who presented with unclear signs and symptoms. Thyroid morphology and function were evaluated with standard ultrasound of the thyroid, scintigraphy and cytological specimen obtained by FNAB. The features of the basic assessment of thyroid status with an emphasis on the concept of “±feedback” of thyroid-stimulating hormone (TSH) and TH. A differential diagnosis of TSH-secreting pituitary adenoma and RTH was discussed. Heterozygous mutation p.P453T in the THRB gene was detected. Thus, the given clinical case demonstrates the necessity of the thorough examination of patients in identifying disorders of the principle of “±feedback”. The observation in dynamics is recommended.

scholarly journals MON-478 Impaired Sensitivity to Thyroid Hormone - A Diagnostic and Therapeutic Challenge

2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Jorge Pedro ◽  
Vanessa Gorito ◽  
Cristina Ferreras ◽  
Ferreira João Silva Maria ◽  
Sofia Ferreira ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Thyroid Function ◽  
Thyroid Function Tests ◽  
Pediatric Endocrinology ◽  
Free T4 ◽  
Peripheral Tissues ◽  
Free T3 ◽  
Function Tests ◽  
Trh Stimulation ◽  
History Of

Abstract Background: Impaired sensitivity to thyroid hormone refers to any process that negatively affects its action, including defects in its transport, metabolism and action on the receptor. Resistance to thyroid hormone due to beta-receptor mutations (RTH-beta) is the most common form of this entity and is characterized by reduced response of peripheral tissues to the action of thyroid hormone. The genetic variability of cofactors involved in the action of thyroid hormone explains the heterogeneity of resistance among affected individuals. Generally, patients with this disorder, have increased levels of free T4 and free T3 in association with normal or high TSH. Clinical case: 11-year-old boy, with personal history of Attention-deficit/hyperactivity disorder (ADHD). A pediatric endocrinology consultation was requested to evaluate abnormalities in his thyroid function tests. A few months earlier, his father was referred to endocrinology consultation because of thyroid function tests abnormalities: TSH - 3.01 μIU / mL (N: 0.35 - 4.94); Free T4 1.7 ng / dL (N: 0.7-1.48); Free T3 4.77 pg / mL (N: 1.71-3.71). Initially, two diagnostic hypotheses were considered: central hyperthyroidism or impaired sensitivity to thyroid hormone. The adult underwent pituitary magnetic resonance, which raised the hypothesis of a pituitary microadenoma, and TRH stimulation test, whose result was strongly suggestive of the second diagnostic possibility. A genetic study was requested and the presence of the c700 G&gt; A variant (p. Ala 324 trh) in the THRB gene was identified, which confirmed the most likely hypothesis. At the time of the pediatric endocrinology consultation, the 11-year-old boy had the results of his lab tests: TSH - 6.67 μIU / mL (N: 0.35 - 5); T4L 2.27 ng / dL (N: 0.88-1.58); T3L 7.79 pg / mL (N: 2-4.20). Given his perfect height and weight evolution and the absence of symptoms suggestive of hypo or hyperthyroidism, it was decided not to start any medication, keeping only periodic surveillance. Conclusion: This case exemplifies unusual thyroid function tests. This discordance between serum thyroid hormone and TSH concentrations should raise the possibility of impaired sensitivity to thyroid hormone. In this condition, patients may present with symptoms of hypo or hyperthyroidism and the etiology of thyroid function tests abnormalities are not easily recognized. This can lead to misdiagnosis and consequently unnecessary treatment.

Comparison of calculated and measured free thyroid hormones in serum in health and in abnormal states.

1982 ◽  
Vol 28 (6) ◽  
pp. 1325-1329 ◽  
Author(s):  
G Fresco ◽  
G Curti ◽  
A Biggi ◽  
B Fontana
Keyword(s):  
Thyroid Hormone ◽  
Thyroid Hormones ◽  
Pregnant Women ◽  
Healthy Subjects ◽  
Normal Subjects ◽  
Mass Action ◽  
Law Of Mass Action ◽  
Free Triiodothyronine ◽  
Free Thyroid Hormones ◽  
Free Thyroid Hormone

Abstract To evaluate a theoretical model for calculating free thyroid hormones, based on the law of mass action, we compared values for both calculated and measured free thyroxin and free triiodothyronine in a group of normal subjects. To determine whether the concentrations of circulating free hormones were also predictable from equilibrium considerations in abnormal states, we compared calculated and measured free thyroid hormone values in an additional population including pregnant women and hyperthyroid, hypothyroid, and "sick euthyroid" patients. Predictions based on the model were accurate in all these states except pregnancy, where there was some discrepancy between calculated and measured values for both hormones. In pregnant women with large abnormalities in thyroid-hormone-binding proteins, euthyroidism was accompanied by significantly lower free hormone concentrations, leading us to conclude that, in pregnancy, equilibrium may be reached at concentrations lower than those in other healthy subjects. Values for calculated and measured free thyroid hormones in "sick euthyroids" showed no discrepancy; however, we cannot exclude the possibility that non-dialyzable compounds are present that interfere with the hormone-protein binding.

scholarly journals Adherence to a Mediterranean Diet and Thyroid Function in Obesity: A Cross-Sectional Apulian Survey

Nutrients ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 3173
Author(s):  
Roberta Zupo ◽  
Fabio Castellana ◽  
Francesco Panza ◽  
Luisa Lampignano ◽  
Isanna Murro ◽  
...  
Keyword(s):  
Thyroid Hormones ◽  
Mediterranean Diet ◽  
Thyroid Function ◽  
Serum Levels ◽  
Overweight And Obesity ◽  
Free T4 ◽  
Cross Sectional ◽  
Free T3 ◽  
Obese Subjects ◽  
The Relationship

Much research suggests that Mediterranean eating habits and lifestyle contribute to counteract the risk of chronic diseases while promoting longevity, but little information is available on the effects of the Mediterranean diet (Med-Diet) on thyroid function, particularly among overweight/obese subjects. Nevertheless, consistent data reported a slight increase in serum levels of the thyroid-stimulating hormone (TSH) and a higher rate of conversion of thyroxine (T4) to triiodothyronine (T3) in obesity. This cross-sectional study was aimed at investigating the relationship between adherence to the Med-Diet and circulating thyroid hormones in a cohort of overweight/obese subjects from Apulia (Southern Italy). Methods: We studied 324 consecutive outpatient subjects (228 women and 96 men, age range 14–72 years) taking no drug therapy and showing normal levels of thyroid hormones, but complicated by overweight and obesity (body mass index (BMI) ≥ 25 Kg/m2). The PREDIMED (PREvención con DIeta MEDiterránea) questionnaire was cross-sectionally administered to assess the adherence to the Med-Diet, and hormonal, metabolic, and routine laboratory parameters were collected. Results: Higher adherence to Med-Diet was found to be inversely related to free T3 (p < 0.01) and T4 (p < 0.01) serum levels. Considering each item in the PREDIMED questionnaire, people consuming at least four spoonfuls of extra-virgin olive oil (EVOO) per day, as well as those consuming at least two servings of vegetables per day, had lower free T3 levels (p 0.033 and p 0.021, respectively). Furthermore, consuming at least four spoonfuls of EVOO per day was found to be associated to lower free T4 serum concentrations (p 0.011). Multinomial logistic regression models, performed on tertiles of thyroid hormones to further investigate the relationship with Med-Diet, corroborated the significance only for free T4. Conclusion: Increased adherence to the Med-Diet was independently associated to a slightly reduced thyroid function, but still within the reference range for free T3 and T4 serum levels. This first finding in this field opens up a research line on any underlying biological interplay.

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