scholarly journals Is a Normal TSH Synonymous With “Euthyroidism” in Levothyroxine Monotherapy?

2016 ◽  
Vol 101 (12) ◽  
pp. 4964-4973 ◽  
Author(s):  
Sarah J. Peterson ◽  
Elizabeth A. McAninch ◽  
Antonio C. Bianco
Keyword(s):  
Large Population ◽  
Density Lipoprotein ◽  
Free T4 ◽  
Lower Serum ◽  
Cross Sectional ◽  
Serum Free ◽  
Free T3 ◽  
Metabolic Equivalents ◽  
Serum T3 ◽  
Serum Tsh

Context: Levothyroxine (LT4) monotherapy is the standard of care for hypothyroidism. Objective: To determine whether LT4 at doses that normalize the serum TSH is associated with normal markers of thyroid status. Design: Cross-sectional data from the US National Health and Nutrition Examination Survey (2001–2012) was used to evaluate 52 clinical parameters. LT4 users were compared to healthy controls and controls matched for age, sex, race, and serum TSH. Regression was used to evaluate for correlation with T4 and T3 levels. Participants: A total of 9981 participants with normal serum TSH were identified; 469 were LT4-treated. Results: Participants using LT4 had higher serum total and free T4 and lower serum total and free T3 than healthy or matched controls. This translated to approximately 15–20% lower serum T3:T4 ratios in LT4 treatment, as has been shown in other cohorts. In comparison to matched controls, LT4-treated participants had higher body mass index despite report of consuming fewer calories/day/kg; were more likely to be taking beta-blockers, statins, and antidepressants; and reported lower total metabolic equivalents. A serum TSH level below the mean in LT4-treated participants was associated with a higher serum free T4 but similar free and total T3; yet those with lower serum TSH levels exhibited higher serum high-density lipoprotein and lower serum low-density lipoprotein, triglycerides, and C-reactive protein. Age was negatively associated with serum free T3:free T4 ratio in all participants; caloric intake was positively associated in LT4-treated individuals. Conclusions: In a large population study, participants using LT4 exhibited lower serum T3:T4 ratios and differed in 12/52 objective and subjective measures.

A STUDY OF PREVALENCE AND PATTERNS OF THYROID DYSFUNCTION IN HIV INFECTED PATIENTS FROM RURAL BACKGROUND OF EASTERN INDIA

2021 ◽  
pp. 31-33
Author(s):  
Amit Sarkar ◽  
Amritesh Biswas ◽  
Kalyan Kumar Bhowmik ◽  
Somnath Dasgupta
Keyword(s):  
Infected Patient ◽  
Thyroid Dysfunction ◽  
Thyroid Function Tests ◽  
Thyroid Disorder ◽  
Free T4 ◽  
Cross Sectional ◽  
Serum Free ◽  
Ciency Virus ◽  
Serum T3 ◽  
Thyroid Abnormalities

The national prevalence of HIV (Human Immunodeciency Virus ) infection among adults in India is estimated to be 0.22% in the year 2017 . Amongst all endocrine abnormalities , abnormal thyroid function tests are common among HIV infected patients . This study is an attempt to know the magnitude of thyroid dysfunction in HIV infected patient . This observational , cross sectional study was carried out on 153 adult patients attending ART centre of our institution . The gross prevalence of thyroid dysfunction in HIV infected patients and patterns of different thyroid abnormalities were assessed .The serum T3 , Free T4 and TSH were correlated with CD4 count and duration of HAART ( highly active anti retroviral therapy) . The prevalence of thyroid dysfunction in HIV infected patient is found to be 30.06% . The most common thyroid disorder , subclinical hypothyroidism was found in 20.26% of the HIV infected patients . Mean CD4 cell count is positively correlated with mean serum T3 and serum free T4 and negatively correlated with mean TSH without any statistical signicance in all study population . The correlation of duration of HAART with serum T3 is signicantly negative and with serum free T4 , TSH is nonsignicantly negative . So, denitely there is more prevalence of thyroid dysfunction in HIV infected patients than general population . Although there is normal serum free T4 level in subclinical hypothyroid patients , the serum free T4 level decreases within the normal laboratory reference range with severity of HIV infection . The thyroid abnormalities progress further in HIV infected patients who are on HAART . We conclude that more attention to thyroid dysfunction in HIV infected patient should be paid so that timely treatment is done .

Comparison of a new ultrafiltration method for serum free T4 and free T3 with two RIA kits in eight groups of patients

1985 ◽  
Vol 8 (6) ◽  
pp. 495-500 ◽  
Author(s):  
Yuh-Shyun Wang ◽  
A. E. Pekary ◽  
M. L. England ◽  
Jerome M. Hershman
Keyword(s):  
Free T4 ◽  
Serum Free ◽  
Free T3

scholarly journals The Effect of Droloxifene and Estrogen on Thyroid Function in Postmenopausal Women1

2000 ◽  
Vol 85 (11) ◽  
pp. 4407-4410
Author(s):  
Ellen Marqusee ◽  
Lewis E. Braverman ◽  
Jennifer E. Lawrence ◽  
Judith S. Carroll ◽  
Ellen W. Seely
Keyword(s):  
Postmenopausal Women ◽  
Treatment Period ◽  
Thyroid Function ◽  
Free T4 ◽  
Double Blind ◽  
Stimulatory Action ◽  
Serum Free ◽  
Serum T4 ◽  
Conjugated Estrogen ◽  
Serum Tsh

Estrogen is known to increase serum T4-binding globulin (TBG) concentrations, thereby increasing serum total T4 concentrations. Serum free T4 concentrations, however, remain normal. Tamoxifen, a selective estrogen receptor modifier (SERM), also raises serum TBG concentrations, but whether newer SERMs with less stimulatory action on the endometrium do so is not known. We, therefore, compared the effect of droloxifene, a SERM, and conjugated equine estrogen on pituitary-thyroid function in normal postmenopausal women. Ten women were treated for 6 weeks with conjugated estrogen (Premarin), 0.625 mg/day, and droloxifene, 60 mg/day, in a double-blind crossover study with an intervening 4-week no-treatment period. We measured serum T4, T3, TBG, free T4 index, and TSH at baseline and at the end of each 6-week period. The baseline values were compared with the 6-week values using paired t tests. The mean (±sd) serum TBG concentrations increased significantly during both treatment periods (baseline, 1.5 ± 0.4 mg/dL; conjugated estrogens, 2.7 ± 0.6 mg/dL; droloxifene, 2.1 ± 0.6 mg/dL; P < 0.001 and P= 0.001, respectively). There were no significant changes in the serum free T4 index. Serum T4 and T3 concentrations increased during both treatment periods, however, the increase was significant only for T4 during the conjugated estrogen treatment period. The serum TSH concentrations increased significantly during both treatment periods (18% during conjugated estrogen and 11% during droloxifene), and the values remained within the normal range in all women. Administration of both conjugated estrogen and droloxifene for 6 weeks increases serum TSH and TBG concentrations, but does not alter free T4 index values in postmenopausal women.

scholarly journals Cross sectional study evaluating the correlation of thyroid dysfunction with severity of disease in rheumatoid arthritis

2020 ◽  
Vol 8 (6) ◽  
pp. 2074
Author(s):  
Vinoth Kumar D. ◽  
Aruna R.
Keyword(s):  
Disease Severity ◽  
Negative Correlation ◽  
Thyroid Dysfunction ◽  
Subjective Assessment ◽  
Systemic Hypertension ◽  
Free T4 ◽  
Das28 Score ◽  
Cross Sectional ◽  
Free T3 ◽  
Das 28

Background: The present study was conducted to evaluate the correlation of disease severity in RA and thyroid dysfunction.Methods: The present cross-sectional descriptive study enrolled 164 participants aged 12 years and above diagnosed as having RA. Use of drugs causing thyroid dysfunction, malignancy, diabetes mellitus, systemic hypertension, pregnancy and prior thyroidectomy were the criteria for exclusion. Data was analyzed using R and tests of significance were Chi square test and independent sample t-test and Pearson correlation. Institutional ethics committee approved the study and written informed consent was obtained from all study participants.Results: Serum TSH positively correlated with DAS 28 (r=0.2, p=0.005), ESR (r=0.2, p=0.03), CRP (r=0.2, p=0.006), RA factor (r=0.2, p=0.003), subjective assessment (r=0.3, p= 0.001) and anti TPO antibodies (r=0.7, p=0.001). Free T4 negatively correlated with DAS28 (r=-0.2, p=0.006), ESR (r=-0.2, p=0.02), CRP (r=-0.2, p=0.01). RA factor (r=-0.2, p=0.01), subjective assessment (r=-0.2, p= 0.01), anti TPO (r=-0.6, p=0.001) and Free T3 negatively correlated with DAS28 score (r=-0.2, p=0.02) , ESR (r=-0.2, p=0.03), RA factor (r=-0.3, p=0.001) and anti TPO antibodies (r=- 0.3, p=0.001).Conclusions: Hypothyroidism was significantly associated with disease severity of RA with linear positive correlation of TSH with DAS28 score, ESR, CRP, RA factor, subjective assessment and anti TPO antibodies, linear negative correlation of serum free T4 with DAS 28 score, ESR, CRP, RA factor, subjective assessment and anti TPO antibody and linear negative correlation of free T3 with DAS28 score, ESR, RA factor and anti TPO antibody was observed.

scholarly journals Does foetal gender influence maternal thyroid parameters in pregnancy?

2022 ◽  
Vol 11 (1) ◽  
Author(s):  
Georgiana Sitoris ◽  
Flora Veltri ◽  
Pierre Kleynen ◽  
Malika Ichiche ◽  
Serge Rozenberg ◽  
...  
Keyword(s):  
Reference Range ◽  
Thyroid Autoimmunity ◽  
First Trimester ◽  
Thyroid Peroxidase ◽  
Reference Ranges ◽  
Free T4 ◽  
Cross Sectional ◽  
Maternal Thyroid ◽  
Serum Tsh ◽  
Tsh Levels

Objective It is unknown if foetal gender influences maternal thyroid function during pregnancy. We therefore investigated the prevalence of thyroid disorders and determined first-trimester TSH reference ranges according to gender. Methods A cross-sectional study involving 1663 women with an ongoing pregnancy was conducted. Twin and assisted pregnancies and l-thyroxine or antithyroid treatment before pregnancy were exclusion criteria. Serum TSH, free T4 (FT4) and thyroid peroxidase antibodies (TPOAb) were measured at median (interquartile range; IQR) 13 (11–17) weeks of gestation. Subclinical hypothyroidism (SCH) was present when serum TSH levels were >3.74 mIU/L with normal FT4 levels (10.29–18.02 pmol/L), and thyroid autoimmunity (TAI) was present when TPOAb were ≥60 kIU/L. Results Eight hundred and forty-seven women were pregnant with a female foetus (FF) and 816 with a male foetus (MF). In women without TAI and during the gestational age period between 9 and 13 weeks (with presumed high-serum hCG levels), median (IQR range) serum TSH in the FF group was lower than that in the MF group: 1.13 (0.72–1.74) vs 1.24 (0.71–1.98) mIU/L; P = 0.021. First-trimester gender-specific TSH reference range was 0.03–3.53 mIU/L in the FF group and 0.03–3.89 mIU/L in the MF group. The prevalence of SCH and TAI was comparable between the FF and MF group: 4.4% vs 5.4%; P = 0.345 and 4.9% vs 7.5%; P = 0.079, respectively. Conclusions Women pregnant with an MF have slightly but significantly higher TSH levels and a higher upper limit of the first-trimester TSH reference range, compared with pregnancies with a FF. We hypothesise that this difference may be related to higher hCG levels in women pregnant with a FF, although we were unable to measure hCG in this study. Further studies are required to investigate if this difference has any clinical relevance.

scholarly journals Diverse Genotypes and Phenotypes of Three Novel Thyroid Hormone Receptor-α Mutations

2016 ◽  
Vol 101 (8) ◽  
pp. 2945-2954 ◽  
Author(s):  
Korcan Demir ◽  
Anja L. M. van Gucht ◽  
Muammer Büyükinan ◽  
Gönül Çatlı ◽  
Yavuz Ayhan ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Motor Development ◽  
Thyroid Hormone Receptor ◽  
Clinical Phenotype ◽  
Case Series ◽  
Detailed Knowledge ◽  
Thyroid Function Tests ◽  
Free T4 ◽  
Serum Free ◽  
Free T3

Context: Recently several patients with resistance to thyroid hormone (RTH)-α due to T3 receptor-α (TRα) mutations were identified. The phenotype of these patients consists of varying degrees of growth impairment, delayed bone, mental and motor development, constipation, macrocephaly, and near-normal thyroid function tests. Objective: The objective of the study was to describe the clinical phenotype of three new families with RTHα and thereby gain more detailed knowledge on this novel syndrome. Design, Setting, and Participants: RTHα was suspected in three index patients from different families. Detailed clinical and biochemical assessment and imaging and genetic analyses were performed in the patients and their relatives. In addition, functional consequences of TRα mutations were investigated in vitro. Results: We studied 22 individuals from three families and identified 10 patients with heterozygous TRα mutations: C380fs387X, R384H, and A263S, respectively. The frame-shift mutation completely inactivated TRα, whereas the missense mutations produced milder defects. These mutations were associated with decreasing severity of the clinical phenotype: the patient in family 1 showed severe defects in growth, mental, and motor development, whereas the seven patients in family 3 had only mild clinical features. The most frequent abnormalities were anemia, constipation, and a delay in at least one of the developmental milestones. Serum free T3 ranged from high-normal to high and serum free T4 and rT3 from normal to low. TSH levels were normal in all patients. Conclusions: This large case series underlines the variation in the clinical phenotype of RTHα patients. RTHα should be suspected in subjects when even mild clinical and laboratory features of hypothyroidism are present along with high/high-normal free T3, low/normal free T4, and normal TSH.

scholarly journals Perchlorate and Thiocyanate Exposure and Thyroid Function in First-Trimester Pregnant Women

2010 ◽  
Vol 95 (7) ◽  
pp. 3207-3215 ◽  
Author(s):  
Elizabeth N. Pearce ◽  
John H. Lazarus ◽  
Peter P. A. Smyth ◽  
Xuemei He ◽  
Daniela Dall'Amico ◽  
...  
Keyword(s):  
Pregnant Women ◽  
Thyroid Function ◽  
Sodium Iodide ◽  
Urinary Iodine ◽  
First Trimester ◽  
Iodine Intake ◽  
Sodium Iodide Symporter ◽  
Free T4 ◽  
Cross Sectional ◽  
Serum Tsh

Context: Thyroid hormone, requiring adequate maternal iodine intake, is critical for fetal neurodevelopment. Perchlorate decreases thyroidal iodine uptake by competitively inhibiting the sodium/iodide symporter. It is unclear whether environmental perchlorate exposure adversely affects thyroid function in pregnant women. Thiocyanate, derived from foods and cigarette smoke, is a less potent competitive sodium/iodide symporter inhibitor than perchlorate. Objective: Our objective was to determine whether environmental perchlorate and/or thiocyanate exposure is associated with alterations in thyroid function in pregnancy. Design and Setting: We conducted a cross-sectional study at health centers in Cardiff, Wales, and Turin, Italy. Patients: During 2002–2006, 22,000 women at less than 16 wk gestation were enrolled in the Controlled Antenatal Thyroid Screening Study. Subsets of 261 hypothyroid/hypothyroxinemic and 526 euthyroid women from Turin and 374 hypothyroid/hypothyroxinemic and 480 euthyroid women from Cardiff were selected based on availability of stored urine samples and thyroid function data. Main Outcome Measures: Urinary iodine, thiocyanate, and perchlorate and serum TSH, free T4 (FT4), and thyroperoxidase antibody were measured. Results: Urinary iodine was low: median 98 μg/liter in Cardiff and 52 μg/liter in Turin. Urine perchlorate was detectable in all women. The median (range) urinary perchlorate concentration was 5 μg/liter (0.04–168 μg/liter) in Turin and 2 μg/liter (0.02–368 μg/liter) in Cardiff. There were no associations between urine perchlorate concentrations and serum TSH or FT4 in the individual euthyroid or hypothyroid/hypothyroxinemic cohorts. In multivariable linear analyses, log perchlorate was not a predictor of serum FT4 or TSH. Conclusions: Low-level perchlorate exposure is ubiquitous but did not affect thyroid function in this cohort of iodine-deficient pregnant women.

Effect of Propranolol on Serum Free T4 and Free T3 in Healthy Subjects

1984 ◽  
Vol 66 (2) ◽  
pp. 69P-69P
Author(s):  
M.R. Wilkins ◽  
J.A. Franklyn ◽  
K.L. Woods ◽  
M.J. Kendall
Keyword(s):  
Healthy Subjects ◽  
Free T4 ◽  
Serum Free ◽  
Free T3

scholarly journals L-thyroxine-treated patients with nodular goiter have lower serum TSH and lower frequency of papillary thyroid cancer: results of a cross-sectional study on 27 914 patients

2010 ◽  
Vol 17 (1) ◽  
pp. 231-239 ◽  
Author(s):  
E Fiore ◽  
T Rago ◽  
M A Provenzale ◽  
M Scutari ◽  
C Ugolini ◽  
...  
Keyword(s):  
Thyroid Cancer ◽  
Papillary Thyroid Cancer ◽  
Nodular Goiter ◽  
Progressive Increase ◽  
Cross Sectional Study ◽  
Papillary Thyroid ◽  
Normal Range ◽  
Lower Serum ◽  
Cross Sectional ◽  
Serum Tsh

The risk of papillary thyroid cancer (PTC) is related to serum TSH, and the development of thyroid autonomy by reducing TSH levels decreases the frequency of PTC in patients with nodular goiter. Our aim was to investigate the effect of l-thyroxine (l-T4) on the frequency of PTC diagnosed by cytology in a large series of patients with nodular goiter untreated (n=20 055) or treated with l-T4 (n=7859). l-T4-treated patients with respect to untreated patients presented significantly lower serum TSH (median, interquartile range: 0.30 μU/ml, 0.08–0.62 μU/ml versus 0.70 μU/ml, 0.38–1.14 μU/ml; P<0.0001) and prevalence of PTC (3.2 vs 5.1%; P<0.0001). The frequency of PTC was closely related to serum TSH, with it being lowest in patients with TSH below the normal range (<0.4 μU/ml; 189/10 059, 1.9%) and highest in patients with TSH above the normal range (>3.4 μU/ml; 21/127, 16.5%), also showing a progressive increase from the lower to the upper quartile of normal range. A significantly higher proportion of l-T4-treated patients (6650/7859, 84.6%) had serum TSH below the median (0.90 μU/ml) with respect to untreated patients (12 599/20 055, 62.8%; χ2 P value <0.0001), with it being included in the range of TSH associated with a lower frequency of PTC. The relationship between serum TSH and frequency of PTC was unrelated to the type of nodularity (solitary versus multinodular) and was not age dependent. In conclusion, patients with nodular goiter, treatment with l-T4 is responsible for the reduction of serum TSH and is associated with a decreased frequency of PTC.

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