An interventional study of Oral Glucose Tolerance Test in Graves Disease and Thyroid Cancer, sponsored by University of Ulm. Recruiting at 1 site in Germany. Per ClinicalTrials.gov, last updated 2026-02-13.
Sponsored by University of Ulm · Not applicable, Interventional, and Basic science
The goal of this clinical trial to clarify the impact of changes in thyroid hormone levels on glucose and lipid metabolism.
Patients will be included in whom thyroid hormone levels are intentionally changed by treatment. In patients with Graves' disease, thyroid hormone levels will be lowered using medication, while in patients with thyroid cancer, thyroid hormone levels will be raised using medication. Oral glucose tolerance tests will be performed before treatment and at two time points after treatment begins to assess metabolic effects.
This research project aims to clarify the role of changes in thyroid hormone levels in glucose and liver metabolism.
Thyroid hormones regulate endogenous glucose production, insulin sensitivity, lipid metabolism, and lipid storage in the liver. They also appear to enhance insulin sensitivity in other tissues. Furthermore, thyroid hormones stimulate lipolysis and reduce total and LDL-cholesterol levels. The impact of thyroid hormones on insulin secretion is controversial, with some trials demonstrating increased secretion and others showing decreased secretion. Most of this evidence is derived from animal trials, and prospective human trials are lacking.
Clinical scenarios where thyroid hormone levels are altered through therapeutic interventions will be used. In patients with Graves' disease, hyperthyroidism is pharmacologically reduced, whereas in patients with thyroid carcinoma, hyperthyroidism is pharmacologically induced. Before the start of treatment, two weeks and three months after start of treatment oral glucose tolerance tests will be performed for metabolic characterization. Using this approach, differences in glycemic, insulin sensitivity, insulin secretion, lipids, resting energy expenditure, respiratory quotient, hepatic steatosis, eating and exercise behavior will be assessed.
162 studies on the registry are indexed under Graves Disease; 53 are open to participants now.
This study's planned enrollment of 60 is close to the median of 60 across 104 interventional studies indexed under Graves Disease.
Browse Graves Disease studies →University of Ulm is the lead sponsor of 143 studies on the registry; 25 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Patients with Graves' disease and patients with thyroid carcinoma undergoing standard-of-care thyroid treatment.
Other: Oral Glucose Tolerance Test
Participants will receive a 75 g oral glucose tolerance (3h) before the start of treatment, two weeks and three months after start of treatment. Body composition will measured by bioimpedance analysis. Before and during the oral glucose tolerance test, indirect calometry will assess metabolic flexibility.
Insulin sensitivity
Effect of changes in thyroid hormone levels on whole-body insulin sensitivity, assessed from glucose and insulin measurements during the 75 g oral glucose tolerance test.
Time frame: Baseline, 2 weeks, 3 months
Insulin secretion
Effect of changes in thyroid hormone levels on insulin secretion, assessed from glucose and insulin/c-peptide measurements during the 75 g oral glucose tolerance test.
Time frame: Baseline, 2 weeks, 3 months
Resting energy expenditure.
Effect of changes in thyroid hormone levels on resting energy expenditure assessed by indirect calometry before and during the 75 g oral glucose tolerance test.
Time frame: Baseline, 2 weeks, 3 months
Respiratory Quotient
Effect of changes in thyroid hormone levels on respiratory quotient assessed by indirect calometry before and during the 75 g oral glucose tolerance test.
Time frame: Baseline, 2 weeks, 3 months
Lipid metabolism
Effect of changes in thyroid hormone levels on lipid metabolism assessed from lipid measurements during the 75 g oral glucose tolerance test.
Time frame: Baseline, 2 weeks, 3 months
Hepatic steatosis
Presence of hepatic steatosis assessed by liver ultrasound including elastography.
Time frame: baseline
Heart rate variability
Effect of changes in thyroid hormone levels on heart rate variability assessed by electrocardiography during the 75 g oral glucose tolerance test.
Time frame: Baseline, 2 weeks, 3 months
Eating behavior
Effect of changes in thyroid hormone levels on eating behavior assessed by dietary protocols before the start of treatment and 3 months later.
Time frame: Baseline, 3 months
Perceived quality of life
Quality of life assessed by the World Health Organization Quality of Life- Brief (BREF) Questionnaire on a 0-100 scale where higher values indicate better quality of life.
Time frame: either at baseline, two weeks or three months
Perceived chronic stress
Perceived chronic stress in the last three months assessed through the trier inventory for chronic stress (TICS-9) on a 0-45 scale on which higher values indicate higher chronic stress.
Time frame: cross-sectional either at baseline, two weeks or three months
Perceived Stress in the last month
Perceived stress in the last months assessed through Perceived Stress Scale (PSS) on a 0-40 scale where higher values indicate higher perceived stress
Time frame: cross-sectional either at baseline, two weeks or three months
Somatization, anxiety and depression
Somatization, anxiety and depression assessed through the Brief symptom inventory (BSI-18) on a 0-77 scale where higher values indicate higher distress
Time frame: cross-sectional either at baseline, two weeks or three months
Plan to share: No
No publications or documents are linked to this record.
Started Feb 2026 (actual). Primary completion is estimated for Feb 2031, 60 months after the start.
Of 22 interventional studies with no phase under Graves Disease, half reached primary completion within 47 months of starting (the median), counting those still running; a quarter within 35 and three quarters within 88. This study's planned 60 months is above that.
How these figures are worked out, and which studies are left out of them.
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