Interrelations Between FT3, FT4 and Pituitary TSH
Information source: Klinikum Lüdenscheid
ClinicalTrials.gov processed this data on August 23, 2015 Link to the current ClinicalTrials.gov record.
Condition(s) targeted: Thyroid
Phase: N/A
Status: Completed
Sponsored by: Klinikum Lüdenscheid Official(s) and/or principal investigator(s): Rolf Larisch, Prof, Principal Investigator, Affiliation: Klinikum Lüdenscheid Department of Nuclear Medicine Rudolf Hoermann, Prof, Study Chair, Affiliation: Klinikum Luedenscheid Department of Nuclear Medicine
Summary
TSH plays a central role in current thyroid function testing both as a diagnostic tool and
therapeutic target. Recent studies have suggested a more complex and hierarchical
relationship between logTSH and FT4 over the entire functional spectrum than the widely
assumed single log linear gradient (1-4). Our group has also shown a disjoint between
pituitary TSH and FT3 serum levels being operative under conditions of levothyroxine
monotherapy (5).
The present prospective observational study aims at confirming some of these findings and
exploring additional factors other than TSH that may be important in shaping the
interrelation of thyroid parameters and modulating thyroidal activity in health and disease.
To this purpose, unselected patients presenting for thyroid testing or treatment to a
specialised unit at a teaching hospital will be prospectively studied to assess the
interplay of FT3, FT4 and TSH under various conditions, and to evaluate various thyroidal
and non-thyroidal influences, such as disease entity, thyroid volume, deiodinase activity,
thyroid medication, surgery, radioiodine treatment, age, BMI, smoking on pituitary set-point
and homeostatic equilibria.
Clinical Details
Official title: Interrelations Between FT3, FT4 and Pituitary TSH and Implications For Thyroid Hormone Treatment (IIFHT-Study)
Study design: Time Perspective: Prospective
Primary outcome: Pituitary setpoint and thyroid hormone equilibria
Detailed description:
Study Design: Prospective observational cross-sectional monocentre study
Eligible Patients: Adult subjects presenting for thyroid testing or treatment to the
Department of Nuclear Medicine, Klinikum Luedenscheid, Luedenscheid, Germany.
Inclusion criteria: All consecutively seen subjects who consent to precipitate and to fill
out a questionnaire, which represent the full functional spectrum, as seen in a praxis
setting.
Exclusion criteria from analysis: Missing consent, severe illness that may be associated
with euthyroid sick syndrome (non-thyroidal illness syndrome), pregnancy, pituitary and
hypothalamic disorders as well as medication that may impair pituitary thyroid hormone
feedback
Methods: Except for a detailed questionnaire the study includes routine work-up,
established standard procedures for diagnosis and standard care for treatment of thyroid
disease Patient history and physical examination Detailed questionnaire on disease history
and medication Measurement of thyroid function parameters and autoantibodies Ultrasound of
thyroid gland and scintigraphy where required
Statistical analysis includes group comparisons, correlations, generalised linear models
with multiple covariates and more advanced modelling techniques of feedback control and FT3-
FT4-TSH interrelations, as previously described (4, 5, 6).
Outcome Measures: Group comparisons among treated patients and untreated subjects and
various disease entities, modelling of lnTSH interactions with FT4 and FT3,influence of
clinically relevant covariates on FT3-FT4-TSH interrelations and equilibria.
Estimated Enrolment : approx. 1500 patients
Estimated Duration: approx. 12 months
Ethical approval: Ethical Committee of the University of Muenster, Muenster, Germany
Sponsor: none
Financial Support: none
Conflicts of Interest: none
Eligibility
Minimum age: 18 Years.
Maximum age: N/A.
Gender(s): Both.
Criteria:
Inclusion Criteria:
- All consecutively seen subjects who consent to precipitate and to fill out a
questionnaire, which represent the full functional spectrum, as seen in a praxis
setting.
Exclusion Criteria:
- Missing consent, severe illness that may be associated with euthyroid sick syndrome
(non-thyroidal illness syndrome), pregnancy, pituitary and hypothalamic disorders as
well as medication that may impair pituitary thyroid hormone feedback.
Locations and Contacts
Department of Nuclear Medicine Klinikum Luedenscheid, Luedenscheid, NRW 58515, Germany
Additional Information
Related publications: Hoermann R, Eckl W, Hoermann C, Larisch R. Complex relationship between free thyroxine and TSH in the regulation of thyroid function. Eur J Endocrinol. 2010 Jun;162(6):1123-9. doi: 10.1530/EJE-10-0106. Epub 2010 Mar 18. Midgley JE, Hoermann R, Larisch R, Dietrich JW. Physiological states and functional relation between thyrotropin and free thyroxine in thyroid health and disease: in vivo and in silico data suggest a hierarchical model. J Clin Pathol. 2013 Apr;66(4):335-42. doi: 10.1136/jclinpath-2012-201213. Epub 2013 Feb 19. Clark PM, Holder RL, Haque SM, Hobbs FD, Roberts LM, Franklyn JA. The relationship between serum TSH and free T4 in older people. Postgrad Med J. 2012 Nov;88(1045):668-70. doi: 10.1136/postgradmedj-2011-200433rep. Hadlow NC, Rothacker KM, Wardrop R, Brown SJ, Lim EM, Walsh JP. The relationship between TSH and free Tâ‚„ in a large population is complex and nonlinear and differs by age and sex. J Clin Endocrinol Metab. 2013 Jul;98(7):2936-43. doi: 10.1210/jc.2012-4223. Epub 2013 May 13. Hoermann R, Midgley JE, Larisch R, Dietrich JW. Is pituitary TSH an adequate measure of thyroid hormone-controlled homoeostasis during thyroxine treatment? Eur J Endocrinol. 2013 Jan 17;168(2):271-80. doi: 10.1530/EJE-12-0819. Print 2013 Feb. Dietrich JW, Landgrafe G, Fotiadou EH. TSH and Thyrotropic Agonists: Key Actors in Thyroid Homeostasis. J Thyroid Res. 2012;2012:351864. doi: 10.1155/2012/351864. Epub 2012 Dec 30.
Starting date: July 2013
Last updated: September 1, 2014
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