onlinear Modelling of Thyroid Hormones' Effect on Thyrotropin Incretion in Confirmed Open-loop Situatio

Conditions: E00
E03
E89.0
E06
E05
E07.1
Postprocedural hypothyroidism
Thyroiditis
Thyrotoxicosis [hyperthyroidism]
Dyshormogenetic goitre

Registration Number: DRKS00003153

Lead Sponsor: niversitätsklinikum Bergmannsheil

Brief Summary: Not available

Detailed Description: Not available

Recruitment & Eligibility

Status: Complete

Sex: All

Target Recruitment: 138

Inclusion Criteria

Outpatients with disconnected feedback control due to the following conditions:
Overt primary hypothyroidism with TSH level over 10 mU/l and FT4 level below 0.5 ng/l (Partition 1)
Overt primary hyperthyroidism with TSH level below 0.1 mU/l and FT4 level over 25 ng/l (Partition 3)
All other constellations, if the patient receives substitution therapy with more 1.75 µg Levothyroxin per kg of body mass (Partition 2).
System in equilibrium (e.g. unchanged substitution dose over the past six weeks).
Inpatients may be incluced, if the thyroid disorder is the reason for admission, and if any accompanying condition that my lead to non-thyroidal illness syndrome (NTIS) is excluced.

Exclusion Criteria

* Pituitary or hypothalamic dysfunction
* Severe illness that may be associated with euthyroid sick syndrome (non-thyroidal illness syndrome)
* Medication influencing pituitary function
Pregnancy
* Missing consent for participation in the study

Study & Design

Study Type: observational

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
onlinear correlation of thyrotropin levels with peripheral levothyroxine levels. [Time Frame: Data of individual patients are obtained one work day after consultation (to allow for laboratory investigations). Model comparison will take place immediately after the inclusion of the 100th patient.]<br>Nonlinear modeling of the pituitary response with different models (logarithmic, polynomial, non-competitive divisive inhibition). Selection of one out of different possible mathematical models that suffices an optimal combination of best nonlinear fit (minimal p-value), minimal entropy (as expressed by minimal values for Akaike information criterion, Bayesian information criterion and Hannan-Quinn information criterion) and best compatibility with biochemical mechanisms.<br>

Secondary Outcome Measures

Name	Time	Method
Parameters of feedback inhibition. [Time Frame: Data of individual patients are obtained one work day after consultation (to allow for laboratory investigations). Parameter estimation will take place immediately after the inclusion of the 100th patient.]<br>Extraction of structural parameters out of the model that has been selected (see primary outcome measure)<br>