Intra-individual variation of thyroxin, triiodothyronine, and thyrotropin in treated hypothyroid patients: implications for monitoring replacement therapy.

1988 ◽  
Vol 34 (4) ◽  
pp. 696-699 ◽  
Author(s):  
M C Browning ◽  
W M Bennet ◽  
A J Kirkaldy ◽  
R T Jung
Keyword(s):  
Primary Hypothyroidism ◽  
Free Triiodothyronine ◽  
Post Dose ◽  
Strict Adherence ◽  
Mean Values ◽  
Specimen Collection ◽  
Total Triiodothyronine ◽  
The Mean ◽  
Random Fluctuations ◽  
Hypothyroid Patients

Abstract We measured total thyroxin (TT4), free thyroxin (FT4), total triiodothyronine (TT3), free triiodothyronine (FT3), and thyrotropin (TSH) in serum sampled before and 1, 2, 4, 6, and 8 h after administration of prescribed doses of thyroxin to 12 patients with proven primary hypothyroidism. At 2, 4, and 6 h post-dose, the mean values for TT4 and FT4 and also that at 8 h for FT4 significantly (P less than 0.05) exceeded the corresponding pre-dose values. No significant changes were found for TT3, FT3, or TSH. The mean intra-individual CVs over the study period were TT4 4.9%, FT4 5.7%, TT3 8.7%, FT3 8.7%, and TSH 20.2%. Individual subjects showed small but predictable changes in TT4 and FT4. Changes in TT3 and FT3 were greater but random. Fluctuations in TSH were greatest, but in all subjects with detectable concentrations the variations were of similar magnitude. We conclude that strict adherence to timing of specimen collection in relation to dosage is probably unnecessary.

Intra- and interindividual biological variation of five analytes used in assessing thyroid function: implications for necessary standards of performance and the interpretation of results.

1986 ◽  
Vol 32 (6) ◽  
pp. 962-966 ◽  
Author(s):  
M C Browning ◽  
R P Ford ◽  
S J Callaghan ◽  
C G Fraser
Keyword(s):  
Reference Range ◽  
Population Based ◽  
Biological Variation ◽  
Reference Ranges ◽  
Hormone Concentration ◽  
Free Triiodothyronine ◽  
Mean Values ◽  
Optimal Patient Care ◽  
Total Triiodothyronine ◽  
The Mean

Abstract Intra- and interindividual components of biological variation have been determined for total thyroxin (TT4), free thyroxin (FT4), total triiodothyronine (TT3), free triiodothyronine (FT3), and thyrotropin (TSH). Calculated analytical goals (CV, %) for the precision required for optimal patient care are: TT4 less than or equal to 2.5, FT4 less than or equal to 4.7, TT3 less than or equal to 5.2, FT3 less than or equal to 3.9, and TSH less than or equal to 8.1. The marked degree of individuality demonstrated for all hormones indicates that, if conventional population-based reference ranges are used uncritically, major changes in hormone concentration may not be correctly identified for some patients because observed values continue to lie within the reference range. At analyte concentrations approximating the mean values found in this study, and for analytical performance meeting the appropriate analytical goal, the differences required for consecutive results to be significantly different (p less than or equal to 0.5) have been calculated as: TT4, 14.7 nmol/L; FT4, 5.7 pmol/L; TT3, 0.6 nmol/L; FT3, 1.3 pmol/L, and TSH, 0.7 milli-int. unit/L.

Lacking evidence for release of thyroid hormones from circulating thyroglobulin during subtotal thyroidectomy

1988 ◽  
Vol 117 (2) ◽  
pp. 219-224 ◽  
Author(s):  
J. Date ◽  
M. Blichert-Toft ◽  
U. Feldt-Rasmussen ◽  
V. Haas
Keyword(s):  
Thyroid Hormones ◽  
Mean Value ◽  
Thyroid Stimulating Hormone ◽  
Mean Values ◽  
Thyroid Resection ◽  
Free Thyroxine Index ◽  
Total Triiodothyronine ◽  
Total Thyroxine ◽  
The Mean ◽  
Peak Value

Abstract. The effect of subtotal thyroid resection for thyrotoxicosis on concentrations of serum thyroid hormones and thyroglobulin (Tg), was determined in 10 patients during operation and the subsequent 18 days. Mean serum Tg responded drastically, increasing from a pre-operative value of 0.30 nmol/l to a peak value of approximately 26 nmol/l during operation followed by a gradual decline to levels lower than before surgery on day 18. Mean serum total thyroxine was 114 nmol/l pre-operatively and free thyroxine index (FT4I) 105 units. Both fluctuated only slightly during operation. Postsurgically, the mean values decreased to below 50% of the pre-operative level. Mean serum total triiodothyronine (TT3) was 1.46 nmol/l pre-operatively. It decreased during operation, reaching a nadir of 0.55 nmol/l on day 2, whereafter the concentration increased slightly. Mean serum reverse T3 (rT3) was 0.45 nmol/l pre-operatively, increased 62% during surgery, and decreased postsurgically. The mean value of serum thyroid stimulating hormone (TSH) was 0.61 mU/l pre-operatively and remained below 1 mU/l during and after operation, but from day 10 concentration began to rise steadily. It is concluded that the vast release of Tg during thyroid resection did not contribute to the concentration of serum T4 to an extent of clinical relevance.

scholarly journals Power Spectral Analysis of Heart Rate Variability In Hypothyroidism

1970 ◽  
Vol 5 (2) ◽  
pp. 53-59 ◽  
Author(s):  
Matia Ahmed ◽  
Noorzahan Begum ◽  
Sultana Ferdousi ◽  
Shelina Begum ◽  
Taskina Ali
Keyword(s):  
Spectral Analysis ◽  
Nervous Activity ◽  
Power Spectral Analysis ◽  
Autonomic Nervous Activity ◽  
Mean Values ◽  
Power Spectral ◽  
Group A ◽  
The Mean ◽  
Hypothyroid Patients ◽  
Serum Tsh

Background: Hypothyroidism is one of the common clinical problems with high incidence in women particularly in older age. It has profound effect on metabolic processes in almost all tissue of the body and heart is particularly sensitive to thyroid hormone action. Power spectral analysis (PSA)is useful to determine the cardiac autonomic regulation by assessing sympathovagal balance. Objectives: To assess the cardiac autonomic nervous activity by power spectral analysis of heart rate variability in patients with hypothyroidism.Method: This cross sectional study was carried out in the Department of Physiology, Banghabandhu Sheikh Mujib Medical University from 1st July 2008 to 30th June 2009 on 60 female patients of 30-50 years with hypothyroidism (group B). For comparison, 30 age sex matched apparently healthy euthyroid subjects (group A) were also studied. Based on treatment, hypothyroid patients were divided into B1 (patients on their 1st day of diagnosis, before starting of treatment) and B2 (patients with medication for 12-18 months). The patients were selected from the Out Patients Department of Endocrinology, BSMMU. Serum TSH and FT4 levels of all subjects were measured by AxSYM system. To perform power spectral analysis of HRV Total Power (TP), Low Frequency (LF), High Frequency (HF), LF norms (nu), HF norms (nu) and LF/HF ratio were assessed by a Polyrite. For statistical analysis of data, Independent Sample t test, One Way ANOVA and Pearson’s correlation coefficient test were done as applicable.Results: The mean serum TSH (38.16 vs2.18; 2.04) was significantly higher and FT4 (5.12vs 15.13; 15.08) was significantly lower (p<0.001) in group B1 than those of group A and B2. The mean values of all the spectral parameters of HRV in euthyroid subjects were within normal range. In untreated hypothyroid patients the mean values of TP (77.11vs2702.87; 2683.73), HF power (56.68 vs 342.02; 437.34) HF nu (24.79 vs 36.35; 34.55) were found significantly (p<0.001) lower LF/HF (1.7±0.3,3.16±.84 and 1.93±.58) and LF nu (75.32 vs 63.71, and 65.90) were significantly (p<0.001) higher and in comparison to both euthyroids and treated patients. Conclusion: Alteration in cardiac autonomic nervous activity characterized by reduced vagal modulation and higher sympathetic activity may occur in the hypothyroid patients.Keywords: HRV; LF HF LF/HF Hypothyroidism DOI: 10.3329/jbsp.v5i2.6777J Bangladesh Soc Physiol. 2010 December; 5(2): 53-59

Free thyroxine, free triiodothyronine, and thyrotropin concentrations in hypothyroid and thyroid carcinoma patients receiving thyroxine therapy

1987 ◽  
Vol 116 (3) ◽  
pp. 418-424 ◽  
Author(s):  
K. Liewendahl ◽  
T. Helenius ◽  
B.-A. Lamberg ◽  
H. Mähönen ◽  
G. Wägar
Keyword(s):  
Thyroid Carcinoma ◽  
Equilibrium Dialysis ◽  
Primary Hypothyroidism ◽  
Free Thyroxine ◽  
Suppressive Therapy ◽  
Free Triiodothyronine ◽  
Thyroxine Therapy ◽  
Thyroxine Replacement ◽  
Hypothyroid Patients ◽  
Serum Tsh

Abstract. Free thyroxine (FT4) and free triiodothyronine (FT3) concentrations in serum were measured by direct equilibrium dialysis methods in patients receiving thyroxine replacement or suppression therapy. Four of 50 hypothyroid patients euthyroid on replacement therapy (mean thyroxine dose 120 μg/day) had supra-normal FT4 concentrations, whereas the FT3 concentrations were normal in all. Forty-one of 56 operated thyroid carcinoma patients on suppressive therapy (mean thyroxine dose 214 μg/day) had raised FT4 concentrations, whereas the FT3 concentration was elevated in only one patient. There was a large difference in mean FT4 values for hypothyroid and thyroid carcinoma patients (17.2 vs 29.5 pmol/l), whereas the difference in mean FT3 values was small (5.0 vs 6.1 pmol/l), suggesting a decreased peripheral conversion of T4 to T3 with increasing concentrations of FT4. Serum TSH concentrations, as determined by an immunoradiometric assay, varied from < 0.02 to 11.9 mU/l in treated hypothyroid patients; 21 patients (42%) had values outside the reference limits. As a single test, serum TSH is therefore not very useful for the assessment of adequate thyroxine dosage in patients with primary hypothyroidism. In thyroid carcinoma patients, the TSH concentrations were < 0.18 mU/l; 45 patients had values < 0.02 mU/l indicating sufficient suppression of TSH secretion in the majority of cases. On the basis of these results we recommend the combination of FT3 and TSH tests for monitoring thyroxine replacement and suppression therapy. FT4 appears less useful than FT3 for this purpose even if special reference values values were adopted for each patient group.

scholarly journals Thyroid Hormones Pattern in Preeclampsia.

2018 ◽  
Vol 24 (S) ◽  
pp. 863-866
Author(s):  
Rabia Sattar ◽  
Ejaz Ahmed ◽  
Sana Qanber Abbasi
Keyword(s):  
Thyroid Hormones ◽  
Cross Sectional Study ◽  
Third Trimester ◽  
Free Triiodothyronine ◽  
Cross Sectional ◽  
Pakistani Population ◽  
Significant Difference ◽  
Total Triiodothyronine ◽  
Total Thyroxine ◽  
The Mean

Objectives: To assess thyroid hormones pattern in preeclampsia in third trimester, in our Pakistani population (Punjab). Methods| It was a Comparative cross- sectional study. Thyroid hormones; namely thyrotropin (TSH), Total triiodothyronine (tT3), free triiodothyronine (fT3), Total thyroxine (tT4) and free thyroxine (fT4) were evaluated by enzyme linked immunoassay (ELISA) in 17 diagnosed preeclamptic subjects with 16 number of matched normotensive pregnant subjects. Data was entered in the form of a questionnaire and analyzed by using version SPSS 17. Results| In this study the mean TSH concentration was 100% higher in preeclamptic subjects as compared to normotensive pregnant subjects, whereas Mean of tT3, tT4, fT3 and fT4were lower when compared between healthy normotensive pregnant and preeclamptic women but no significant difference was seen between both the groups. Conclusion| This study shows statistically non-significant increase in TSH levels and decrease in total and free T3 and T4 levels of PE as compared to the normotensive pregnant subjects.

scholarly journals EFFECT OF NERVE CONDUCTION STUDIES IN HYPOTHYROIDISM - AN OBSERVATIONAL STUDY

2018 ◽  
Vol 11 (8) ◽  
pp. 326
Author(s):  
Lalithamma A ◽  
Vadivel S ◽  
Johnson W ◽  
Jacob V ◽  
Chitra T
Keyword(s):  
Observational Study ◽  
Conduction Velocity ◽  
Short Duration ◽  
Nerve Conduction ◽  
Nerve Conduction Velocity ◽  
Initial Time ◽  
Newly Diagnosed ◽  
Mean Values ◽  
The Mean ◽  
Hypothyroid Patients

Objective: This observational study was conducted during the year 2016–2017 to assess the electrodiagnostic evidence of peripheral nerve dysfunction among newly diagnosed hypothyroid patients attending a tertiary care hospital and to find the effect of hormonal treatment after short duration. Methods: An observational study was conducted in 25 newly diagnosed hypothyroid patients with the age group of 20–60 were included. After obtaining informed consent, all participants were examined with electrodiagnostic workup performed at the initial time of diagnosis and after short duration for median and ulnar nerves of upper limb by (NeuroStim -NS2, EMG/EP/NCV, and MEDICAID SYSTEMS). Electrophysiological parameters such as distal motor latency, amplitude, and conduction velocity were evaluated. Results: The mean age of study population was 42.7±12.1 (23–61) years. The mean values of nerve conduction velocity of motor and sensory median before the treatment were 42.8±15.7 and 40.13±4.19 and motor and sensory ulnar before treatment were 41.18±22.4 and 39.46±11.9. The mean values of nerve conduction velocity of motor and sensory median after treatment were 53.35±4.7 and 57.3±5.6 and motor and sensory ulnar After treatment were 54.56±2.99 and 54.09±12.17. The result of the study. Shows that there were reduction of conduction velocity before treatment and statistically significant after 3 months duration of treatment with appropriate doses. Conclusion: After treatment, total triiodothyronine, total thyroxin, free triiodothyronine, free thyroxin, thyroid-stimulating hormone, and median and ulnar nerve motor and sensory functions were normal with appropriate treatment. The involvement of sensory fibers is more than that of the motor fibers.

SOMATOMEDIN A IN HUMAN SERUM, DETERMINED BY RADIORECEPTOR ASSAY

1976 ◽  
Vol 82 (2) ◽  
pp. 449-459 ◽  
Author(s):  
K. Takano ◽  
K. Hall ◽  
M. Ritzén ◽  
L. Iselius ◽  
H. Sievertsson
Keyword(s):  
Human Serum ◽  
Primary Hypothyroidism ◽  
Radioreceptor Assay ◽  
Turner's Syndrome ◽  
Turner’S Syndrome ◽  
Mean Values ◽  
The Mean ◽  
Low Levels

ABSTRACT Somatomedin A was determined by radioreceptor assay in serum from patients with various disorders. The mean values of somatomedin A in serum from 20 adult subjects, 21 patients with acromegaly, and 17 patients with hypopituitary dwarfism were 1.08 ± 0.08, 3.02 ± 0.33 and 0.44 ± 0.03 U/ml, respectively. In children below 2 years of age, low levels were found (mean 0.40 ± 0.04 U/ml). Normal levels were found in patients with Turner's syndrome and primary hypothyroidism, increased levels in uraemic patients, and decreased levels in Laron dwarfs.

scholarly journals OR10-04 Interpretation of Insulin-like Growth Factor-1 (IGF-1) Levels Following Administration of Somatrogon (a Long-acting Human Growth Hormone - hGH-CTP)

2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Dennis M Fisher ◽  
Aleksandra Pastrak ◽  
John Choe ◽  
Michael Paul Wajnrajch ◽  
José Cara
Keyword(s):  
Clinical Decision Making ◽  
Human Growth ◽  
Concentration Data ◽  
Phase 3 ◽  
Post Dose ◽  
Pivotal Phase ◽  
Mean Values ◽  
Dosing Interval ◽  
The Mean ◽  
Long Acting

Abstract IGF-1 is often used as a biomarker to evaluate the efficacy and safety of hGH replacement therapy. Typically, the mean IGF-1 SDS level during the dosing interval, rather than the peak value, guides clinical decision-making: sustained mean values &gt; +2 may require hGH dose modifications. With long-acting formulations (administered weekly), the IGF-1 evaluation paradigm needs to take into account when the sample was obtained relative to the last administered dose. Previous studies with OPKO’s once weekly Somatrogon (hGH-CTP), demonstrated that IGF-1 SDS peaked ~ 48 hours post-dose and that values at ~ 96 hours best approximated the mean IGF-1 SDS throughout the dosing interval [1]. Data from the pivotal Phase 3 non-inferiority study comparing treatment with Somatrogon to Genotropin allowed further evaluation of the IGF-1 SDS analysis paradigm. Enrolled subjects were randomized to receive treatment with either once weekly Somatrogon (0.66 mg/kg; N=109) or once daily Genotropin (0.034 mg/kg; N=115). IGF1 was sampled ~ five times during 52 weeks of treatment with Somatrogon, providing a total of 557 samples obtained after the first dose of Somatrogon. IGF-1 SDS values were calculated using Bidlingmaier’s equations [2]. Analysis of IGF-I SDS data from the Phase 3 study showed that the previously-developed model, with adjustments to two parameters (baseline IGF-1, EC50) and adapted to fit IGF-1 values in the absence of Somatrogon concentration data, fit the IGF-1 data for Somatrogon with minimal bias. This allowed prediction of IGF-1 SDS values at timepoints throughout the dosing interval as well as calculation of the mean value during a dosing interval. Of the samples obtained between 48–72 hours post-dose (representing peak IGF-1 SDS), approximately 17% had an IGF1 SDS &gt; +2. At 96 hours (corresponding to mean IFG-1 SDS), fewer than 2% of modeled values were &gt; +2. Mean IGF-1 SDS over the dosing interval was between -1 and +1 for all subjects. These findings indicate that IGF-1 SDS values need to be interpreted in the context of when the sample was obtained relative to the last dose of Somatrogon. Our results indicate that samples obtained 96 hours post-dose best represent mean IGF-1 levels and that values obtained between 48–72 hours post-dose represent values closer to peak IGF-1 concentrations. In our Phase 3 study, of the 557 samples collected from 114 patients during the 12-month Somatrogon treatment period, fewer than 2% of the corresponding values at 96 hours postdose (estimated from a pharmacokinetic/pharmacodynamic model) had IGF-1 SDS levels &gt; +2. 1. Fisher DM, et al. Horm Res Paediatr 2017;87:324. 2. Bidlingmaier M, et al. J Clin Endocrinol Metab 2014;99:1712

Effect of thyroid function on serum somatomedin activity

1981 ◽  
Vol 96 (4) ◽  
pp. 491-497 ◽  
Author(s):  
Josef Marek ◽  
Marie Schüllerová ◽  
Olga Schreiberová ◽  
Zdeňka Límanová
Keyword(s):  
Thyroid Hormones ◽  
Replacement Therapy ◽  
Primary Hypothyroidism ◽  
Embryonic Chick ◽  
Mean Values ◽  
Before And After ◽  
And Function ◽  
Hypothyroid Patients ◽  
Hyperthyroid Patients

Abstract. To obtain more information about a possible role of somatomedins in mediating the effects of thyroid hormones on the development and function of epiphyseal cartilage, somatomedin activity, measured on the basis of 35S incorporation in embryonic chick cartilage, was studied in thyrotoxic patients before and after treatment with carbimazole or surgery and in a group of patients with primary hypothyroidism. In 29 hyperthyroid patients mean values of somatomedin were 1.29 ± 0.03 sem and differed significantly (P < 0.01) from normals (1.04 ± 0.03). In 15 carbimazole treated patients and in 5 operated patients with thyrotoxicosis somatomedin levels fell from 1.29 ± 0.04 to 1.03 ± 0.04 (P < 0.01) when the patients became euthyroid. Correspondingly, somatomedin levels in 12 untreated hypothyroid patients (0.82 ± 0.04) were significantly less than in normals (P < 0.01) and increased from 0.77 ± 0.09 to 1.14 ± 0.13 (P < 0.05) in 4 patients on replacement therapy. In conclusion: somatomedin levels rise when thyroid hormones are present in excess, and fall when these are deficient. This suggests that thyroid hormones are important regulators of somatomedin levels.

Articulatory Behavior Pre and Post Full-Mouth Tooth Extraction and Alveoloplasty

1980 ◽  
Vol 23 (3) ◽  
pp. 630-645 ◽  
Author(s):  
Gerald Zimmermann ◽  
J.A. Scott Kelso ◽  
Larry Lander
Keyword(s):  
Control Subject ◽  
High Speed ◽  
Tooth Extraction ◽  
Kinematic Parameters ◽  
Experimental Conditions ◽  
Mean Values ◽  
Articulatory Movements ◽  
The Mean ◽  
Experimental Subjects ◽  
Normal Speech

High speed cinefluorography was used to track articulatory movements preceding and following full-mouth tooth extraction and alveoloplasty in two subjects. Films also were made of a control subject on two separate days. The purpose of the study was to determine the effects of dramatically altering the structural dimensions of the oral cavity on the kinematic parameters of speech. The results showed that the experimental subjects performed differently pre and postoperatively though the changes were in different directions for the two subjects. Differences in both means and variabilities of kinematic parameters were larger between days for the experimental (operated) subjects than for the control subject. The results for the Control subject also showed significant differences in the mean values of kinematic variables between days though these day-to-day differences could not account for the effects found pre- and postoperatively. The results of the kinematic analysis, particularly the finding that transition time was most stable over the experimental conditions for the operated subjects, are used to speculate about the coordination of normal speech.

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