Thyroid and Glucose and Energy Metabolism

Study Results

Results available

Outcome measurements, participant flow, baseline characteristics, and adverse events have been published for this study.

View full results

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Clinical Phase

PHASE2

Total Enrollment

18 participants

Study Classification

INTERVENTIONAL

Study Start Date

2005-03-31

Study Completion Date

2013-11-30

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

This study will examine how two thyroid preparations-levothyroxine (T4) and liothyronine (T3)-affect fat and cholesterol metabolism, blood sugar regulation, and thyrotropin secretion in patients who have had their thyroid gland removed. Results of the study may help in the development of better therapies to optimize blood sugar and cholesterol levels in some patients.

Patients 18 years of age or older who have had most or all of their thyroid gland removed and are taking long-term thyroid hormone medication may be eligible for this study after screening.

Related Clinical Trials

Explore similar clinical trials based on study characteristics and research focus.

Energy Metabolism in Thyroidectomized Patients

NCT04782856

Thyroid Goiter Hypothyroidism Thyroid Cancer

COMPLETED PHASE2

Thyroid Study Type 2 Diabetes Mellitus (T2DM)

NCT01379170

Diabetes Hypothyroidism

UNKNOWN PHASE4

Thyroid and Fat Tissue Metabolism

NCT00312715

Healthy Volunteers

COMPLETED

Desiccated Thyroid Extract Versus Synthetic T3/T4 Combination (ThyrolarTM) Versus L-T4 Alone in the Therapy of Primary Hypothyroidism With Special Attention to the Gene Polymorphism

NCT02317926

Hypothyroidism

UNKNOWN NA

Metabolic Effects of Synthetic Thyroid Hormone for Thyroid Cancer Treatment

NCT01441154

Malignant Struma Ovarii Papillary Thyroid Cancer Hurthle Cell Thyroid Cancer +2 more

COMPLETED

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

Thyroid hormone action plays an important role in the regulation of many physiologic processes, among them glucose and lipid metabolism. Interestingly, the clinical presentation of thyroid dysfunction is extremely variable, with relatively poor correlation between circulating hormone levels and clinical features. This finding suggests that the local, intracellular concentration of the active hormone liothyronine (T3), regulated by peripheral conversion of the pro-hormone levothyroxine (T4), is an important determinant in the maintenance of the thyroidal homeostasis.

The aim of the present study is the evaluation of the role of peripheral thyroid hormone conversion in the regulation of glucose and lipid metabolism by assessing the differential response to T4 or T3 treatment in subjects devoid of endogenous thyroid hormone production. T3 administration bypasses peripheral metabolism and therefore will allow us to assess the role of the peripheral thyroid hormone conversion in the regulation of the hormone action at the end-organ level.

Fifty hypothyroid subjects will be initially randomized to either of the thyroid hormone replacements liothyronine (T3) or levothyroxine (T4) treatment period (one arm cross-over design, with treatment sequence randomized), aimed to maintain serum TSH levels greater than or equal to 0.5 less than or equal to 1.5 mU/L, indicating full replacement. After a 30-day period of steady-state replacement the study subjects will be admitted to the Clinical Center and, after a three-day period of stabilization and an overnight fast, will undergo the following tests: escalating dose TRH stimulation test, indirect calorimetry, graded exercise tolerance test, DEXA scan, and echocardiogram.

Patients will also undergo skeletal muscle biopsy and subcutaneous adipose tissue biopsy and microdialysis, as well as a two-step euglycemic hyperinsulinemic clamp with measurement of splanchnic gluconeogenesis. Fasting venous blood samples will be collected for the determination of the parameters of lipid, glucose and energy metabolism.

After discharge, the patients will switch to the other form of thyroid hormone replacement therapy (second period) . The therapy will be adjusted in order to achieve the same therapeutic goal for TSH concentrations (greater than or equal to 0.5 less than or equal to 1.5 mU/L), analogous to that achieved during the first phase of the study (TSH less than or equal to 0.5 mU/L difference between T3 and T4 phases). After reaching a 30-day period of steady-state replacement, study subjects will be re-admitted to the Clinical Center and the previously described evaluation procedures will be repeated.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Thyroid Diseases

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

RANDOMIZED

Intervention Model

CROSSOVER

Blinding Strategy

TRIPLE

Participants Caregivers Investigators

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

Liothyronine and Levothyroxine

Hypothyroid patients treatment with Levothyroxine and Liothyronine in 2 crossover, randomized phases

Group Type ACTIVE_COMPARATOR

Liothyronine and Levothyroxine

Intervention Type DRUG

Hypothyroid patients are treated with Liothyronine and Levothyroxine in 2 crossover, randomized phases

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

Liothyronine and Levothyroxine

Hypothyroid patients are treated with Liothyronine and Levothyroxine in 2 crossover, randomized phases

Intervention Type DRUG

Other Intervention Names

Discover alternative or legacy names that may be used to describe the listed interventions across different sources.

T3 and T4

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

Age greater than or equal to 18 years, male or female.

History of total or near total thyroidectomy or hypothyroidism on replacement therapy.

For non-thyroidectomized patients, at least three-year history of replacement therapy (at least 1.2 mcg/Kg LT4/body weight), and less than 5% uptake at 24H on (123)I thyroid scan while on replacement therapy.

Written informed consent.

Exclusion Criteria

BMI less than or equal to 20 or greater than or equal to 30 kg/m(2).

Metastatic thyroid cancer or history of thyroid cancer with high risk of recurrence requiring suppressive thyroid hormone therapy (Singer 1996).

Significant thyroid residual greater than 1 mL as measured by ultrasound (limited to thyroidectomized patients) or greater than 5 percent uptake at 24H on (123)I thyroid scan while on replacement therapy (limited to hypothyroid patients not undergone total thyroidectomy).

History or symptoms compatible with cardiovascular disease, including paroxysmal supraventricular tachycardia, atrial fibrillation, syncopal episodes or use of prescription medications for heart conditions, including antihypertensives.

Allergy to lidocaine, isoproterenol, TRH, levothyroxine, liothyronine, Tylenol #3, oxycodone, nitroglycerin.

Pregnancy or unwillingness to use non-hormonal contraception during the study.

Breastfeeding

Use of hormonal contraceptives or estrogen replacement therapy.

Use of tobacco (smoking, chewing) for the two weeks preceding the hospital admissions (metabolic testing)

Diabetes mellitus, either type I or II.

Hypercholesterolemia (serum levels greater than or equal to 240 mg/dL), hypertriglyceridemia (plasma levels greater than or equal to 220 mg/dL) and/or use of antilipemic therapy.

Liver disease or ALT serum level greater than two fold the upper laboratory reference limit.

Renal insufficiency or estimated creatinine clearance less than or equal to 50 mL/min.

Use of medications/supplements/alternative therapies known to alter thyroid function.

Current history or symptoms compatible with psychosis including major depression (including history of hospitalization for depression, history of attempted suicide, history of suicidal ideation).

Use of antipsychotic medications

History of drug or alcohol abuse within the last 5 years; current use of drugs or alcohol (CAGE greater than 3).

Keloid formation (relative to skeletal muscle and subcutaneous adipose tissue biopsies).

Current or previous clinically significant (requiring medical/surgical intervention) extrathyroidal manifestations of autoimmune thyroid disease (dermopathy, ophthalmopathy, arthropathy).

Minimum Eligible Age

18 Years

Maximum Eligible Age

65 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No