Interrelations Between FT3, FT4 and Pituitary TSH

NCT01969552 | Completed

• 1 other identifier: IIFHT-161013
• Study Type: observational
• Target: 1,912
• Locations: 1 country
• Sites: 1

Brief 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.

Conditions

Thyroid

Keywords

TSH, thyroid hormones, thyroid tresting, levothyroxine

Outcome Measures

Primary Outcomes (1)

• Pituitary setpoint and thyroid hormone equilibria

  According to our previous work, the states of hypothyroidism, euthyroidism and hyperthyroidism can be regarded as differently regulated entities. The present study assesses modulators that influence pituitary thyroid feedback control and impact on the pituitary setpoint and hormonal equilibria. The measure is change in circulating levels of TSH (mU/L) per change in FT4 (nmol/L) or FT3 (pmol/L).

  Baseline

Study Arms (1)

Thyroid testing

Adult subjects presenting for thyroid testing or treatment

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

Adult subjects presenting for thyroid testing or treatment to the Department of Nuclear Medicine, Klinikum Luedenscheid, Luedenscheid, Germany.

You may qualify if:

• 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.

You may not qualify if:

• 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.

Sponsors & Collaborators

• Klinikum Lüdenscheid: lead

Study Sites (1)

Department of Nuclear Medicine Klinikum Luedenscheid

Lüdenscheid, North Rhine-Westphalia, 58515, Germany

Location

Related Publications (6)

• 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.

  PMID: 20299491 BACKGROUND

• 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.

  PMID: 23423518 BACKGROUND

• 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.

  PMID: 23097057 BACKGROUND

• Hadlow NC, Rothacker KM, Wardrop R, Brown SJ, Lim EM, Walsh JP. The relationship between TSH and free T(4) 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.

  PMID: 23671314 BACKGROUND

• 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.

  PMID: 23184912 BACKGROUND

• 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.

  PMID: 23365787 BACKGROUND

MeSH Terms

Conditions

Thyroid Diseases

Condition Hierarchy (Ancestors)

Endocrine System Diseases

Study Officials

• Rolf Larisch, Prof

  Klinikum Lüdenscheid Department of Nuclear Medicine

  PRINCIPAL INVESTIGATOR

• Rudolf Hoermann, Prof

  Klinikum Luedenscheid Department of Nuclear Medicine

  STUDY CHAIR

Study Design

• Study Type: observational
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: October 16, 2013
• First Posted: October 25, 2013
• Study Start: July 1, 2013
• Primary Completion: June 1, 2014
• Study Completion: June 1, 2014
• Last Updated: September 3, 2014

Record last verified: 2014-09

Locations

DE (1)