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NOMOTHETICOS: Nonlinear Modelling of Thyroid Hormones' Effect on Thyrotropin Incretion in Confirmed Open-loop Situation (NOMOTHETICOS)

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ClinicalTrials.gov Identifier: NCT01145040
Recruitment Status : Unknown
Verified October 2020 by PD Dr. Johannes W. Dietrich, MD, Ruhr University of Bochum.
Recruitment status was:  Active, not recruiting
First Posted : June 16, 2010
Last Update Posted : October 8, 2020
Sponsor:
Information provided by (Responsible Party):
PD Dr. Johannes W. Dietrich, MD, Ruhr University of Bochum

Tracking Information
First Submitted Date June 14, 2010
First Posted Date June 16, 2010
Last Update Posted Date October 8, 2020
Actual Study Start Date June 1, 2010
Actual Primary Completion Date July 31, 2018   (Final data collection date for primary outcome measure)
Current Primary Outcome Measures
 (submitted: February 9, 2011)
Nonlinear 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. ]
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.
Original Primary Outcome Measures
 (submitted: June 15, 2010)
Nonlinear 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. ]
Nonlinear modelling of the pituitary response with different models (logarithmic, polynomial, non-competitive divisive inhibiton). Selection of one out of different possible mathematical models that suffices an optimal combination of
  1. best nonlinear fit (minimal p-value),
  2. minimal entropy (as expressed by minimal values for Akaike information criterion, Bayesian information criterion and Hannan-Quinn information criterion) and
  3. best compatibility with biochemical mechanisms.
Change History
Current Secondary Outcome Measures
 (submitted: June 15, 2010)
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. ]
Extraction of structural parameters out of the model that has been selected (see primary outcome measure)
Original Secondary Outcome Measures Same as current
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
 
Descriptive Information
Brief Title NOMOTHETICOS: Nonlinear Modelling of Thyroid Hormones' Effect on Thyrotropin Incretion in Confirmed Open-loop Situation
Official Title NOMOTHETICOS: Nonlinear Modelling of Thyroid Hormones' Effect on Thyrotropin Incretion in Confirmed Open-loop Situation. A Correlation Study
Brief Summary The NOMOTHETICOS study is a unicentric cross-sectional study for a quantitative analysis of feedback-inhibition in the thyrotropic homeostatic control. Structural parameters are obtained in vivo from open-loop analysis in patients with disconnected feedback, i.e. with overt thyroid dysfunction or full dose substitution therapy with levothyroxine.
Detailed Description

Control of thyroid hormone homeostasis is essential for function and development of the organism and hence for individual health. It is therefore not surprising that the thyroid's function is controlled by a complex, multi-loop feedback control system.

Today, the central component of the thyrotropic feedback control system is still poorly understood on a physiological level. Therefore, in mathematical models different functional relations describing the feedback-inhibition of thyrotropin incretion by thyroid hormones have been suggested [Danziger and Elmergreen 1956, Roston 1959, Norwich and Reiter 1965, DiStefano and Stear 1968, DiStefano 1969, Saratchandran et al. 1973, Li et al. 1995, Dietrich et al. 2004, Degon et al. 2008, Jonklaas and Soldin 2008, Hörmann et al. 2010]. Most of these models fail in delivering biochemical explanations for the functional interrelations they postulate.

Nevertheless, some clinical applications of these models have been developed, although their diagnostical potential is usually rather limited [Yagi et al. 1997, Pohlenz et al. 1999, Jostel et al. 2009].

Assuming that the pituitary's response to peripheral thyroid hormones is determined by active transmembrane thyroxine transport mechanisms [Dietrich et al. 2008], intracellular deiodination of thyroxine (T4), binding of resulting triiodothyronine (T3) to iodothyronine receptors and, finally, their inhibiting effect on mRNA expression, translation and release of TRH, a novel, physiologically motivated model has been developed that is based on compartment-analytical approaches, Michaelis-Menten kinetics and non competitive divisive inhibition [Dietrich et al 2004]. However, this model has not been sufficiently evaluated in a clinical context.

It is the aim of the NOMOTHETICOS study to deliver new systems-level insights into the pituitary's thyrotropic function. This unicentric cross-sectional study compares different models of feedback-inhibition by means of modern statistical methods like nonlinear regression and Akaike information criterion. Structural parameters are obtained in vivo from open-loop analysis in patients with disconnected feedback in equilibrium.

These parameters can serve as theoretical basis for possible future trials developing advanced diagnostical evaluation methods of thyrotropic pituitary function.

Study Type Observational
Study Design Observational Model: Cohort
Time Perspective: Cross-Sectional
Target Follow-Up Duration Not Provided
Biospecimen Not Provided
Sampling Method Probability Sample
Study Population Outpatients with "open-loop" thyrotropic feedback control (disconnection at the site of the thyroid)
Condition
  • Hypothyroidism
  • Hyperthyroidism
Intervention Not Provided
Study Groups/Cohorts
  • Partition 1
    Overt primary hypothyroidism
  • Partition 2
    Hypothyroidism with "full dose" levothyroxine substitution therapy (more than 1.75 µg per kg of body mass)
  • Partition 3
    Overt primary hyperthyroidism
Publications *

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Recruitment Information
Recruitment Status Unknown status
Actual Enrollment
 (submitted: June 21, 2018)
138
Original Estimated Enrollment
 (submitted: June 15, 2010)
100
Estimated Study Completion Date January 31, 2021
Actual Primary Completion Date July 31, 2018   (Final data collection date for primary outcome measure)
Eligibility Criteria

Inclusion Criteria:

  • Outpatients with disconnected feedback control due to the following conditions:

    • Overt primary hypothyroidism with TSH level higher than 10 mU/l and FT4 concentration below 7 pmol/L (5.4 ng/L) (Partition 1)
    • Overt primary hyperthyroidism with TSH level below 0.1 mU/l and FT4 concentration higher than 18 pmol/L (14 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)

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
Sex/Gender
Sexes Eligible for Study: All
Ages 14 Years and older   (Child, Adult, Older Adult)
Accepts Healthy Volunteers No
Contacts Contact information is only displayed when the study is recruiting subjects
Listed Location Countries Germany
Removed Location Countries  
 
Administrative Information
NCT Number NCT01145040
Other Study ID Numbers TFC-UK10
3718-10 ( Other Identifier: Ethics commission of the Ruhr University of Bochum )
U1111-1122-3273 ( Registry Identifier: WHO ICTRP Universal Trial Number (UTN) )
DRKS00003153 ( Registry Identifier: DRKS (German Clinical Trials Register) )
Has Data Monitoring Committee Yes
U.S. FDA-regulated Product Not Provided
IPD Sharing Statement
Plan to Share IPD: Yes
Plan Description: Data will be made available upon reasonable request.
Supporting Materials: Analytic Code
Current Responsible Party PD Dr. Johannes W. Dietrich, MD, Ruhr University of Bochum
Original Responsible Party Dr. Johannes W. Dietrich, BG Universitätsklinikum Bergmannsheil GmbH
Current Study Sponsor Ruhr University of Bochum
Original Study Sponsor Same as current
Collaborators Not Provided
Investigators
Principal Investigator: Johannes W Dietrich, M.D. Medical Hospital I, Bergmannsheil University Hospitals, Ruhr University of Bochum
Study Chair: Harald H Klein, M.D. Medical Hospital I, Bergmannsheil University Hospitals, Ruhr University of Bochum
Study Director: Johannes W Dietrich, M.D. Medical Hospital I, Bergmannsheil University Hospitals, Ruhr University of Bochum
Principal Investigator: Bojana Bazika-Gerasch, M.D. Medical Hospital I, Bergmannsheil University Hospitals, Ruhr University of Bochum
PRS Account Ruhr University of Bochum
Verification Date October 2020