Neurocognitive and Metabolic Effects of Mild Hypothyroidism
HypothyroidismPatients with hypothyroidism are routinely treated with thyroid hormone (l-thyroxine) for replacement therapy. Physicians monitor the thyroid hormone dose by measuring a thyroid stimulating hormone (TSH) level in the blood, with the goal of a normal level. However, recent data suggest that the "normal" TSH range is too broad, and that patients may still have symptoms if their TSH levels are at the top or bottom part of the normal range. To study this issue, it is useful to address issues such as general health status, psychological symptoms, mood, memory, and metabolic status, since thyroid hormone has major effects on the brain and metabolism, and since patients with treated hypothyroidism often have symptoms related to these areas. In the present study, otherwise healthy subjects with treated hypothyroidism, ages 20-75 years, will be enrolled in a 7-11month study. At baseline, they will have tests of health status, psychological symptoms, mood, memory, body composition, and energy expenditure performed. Following these baseline measurements, subjects will receive either their usual doses of l-thyroxine, or a slightly higher or lower dose. The doses will be chosen to try to achieve either a low-normal TSH level, a high-normal TSH level, or a mildly elevated TSH level. Which target TSH the patient is assigned will be determined randomly, and neither the subject nor the study contacts will know which dose the patient is receiving. Subjects will be seen every 6 weeks during the study for brief visits to make sure they are not having any side effects, and to adjust the l-thyroxine doses if the TSH has not yet reached the target range. At the 24-week visit (end of study), the subjects will undergo the same tests that they had on the baseline visit. Results from the study will be examined to see if minor changes in TSH or other thyroid hormone levels cause changes in any of the outcomes, and if the degree of TSH change correlates with the degree of outcome changes. These results may help physicians caring for patients with thyroid disease better determine the optimal dose of thyroid hormone for each patient.
Effect of T4-T3 Combination Therapy Versus T4 Monotherapy in Patients With Hypothyroidism
Quality of LifeDepressionTo compare the effect of T4-T3 combination therapy versus T4 monotherapy in patients with autoimmune hypothyroidism, on stable T4-substitution therapy
Influence of Initial Levothyroxine Dose on Neurodevelopmental and Growth Outcomes in Congenital...
Congenital HypothyroidismThe primary objective of this study is to evaluate the risk-benefit profile of long-term treatment of two different initials treatment schemes with L-T4 on the neurodevelopmental and auxological outcomes in children with congenital hypothyroidism, diagnosed by neonatal screening in order to find the best dose of initial thyroid hormone replacement to assure the best long-term developmental outcome without any adverse effects on auxological, cardiovascular and skeletal outcomes. The secondary objective of the study is to evaluate the role of other factors that, in addition to the initial L-T4 therapy,can influence long-term neurodevelopmental and auxological outcomes as well as the cardiovascular system and bone metabolism outcomes.
Identification of Non-responders to Levothyroxine Therapy
HypothyroidismBiomarkers1 moreThe purpose of this study is to assess differential effects of T4 and T3 on cell and tissue level
The TRUST Study - Depression Substudy
Subclinical HypothyroidismDepressionMild thyroid failure is a common condition among older adults and has been associated with numerous adverse effects on health, such as cardiovascular disease, cognition disturbances and muscular problems. Mild thyroid failure has also been associated with an increased risk of developing depression. To date, only few studies have investigated the effect of thyroid hormone replacement on depression in patients with mild thyroid failure. This study therefore aims to assess whether thyroid hormone replacement in older adults with mild thyroid failure is associated with a decrease in the presence of depressive symptoms. This study forms a substudy of a large international study on thyroid hormone replacement in older adults with mild thyroid failure (the TRUST study).
Effects of L-carnitine on Hypothyroidism
HypothyroidismL-carnitine and thyroid hormone tended to antagonize reciprocally in human body. Urinary excretion of L-carnitine decreased in hypothyroid patients, and levothyroxine supplementation increased excretion of L-carnitine. The investigators hypothesized that supplying L-carnitine to hypothyroid patients with fatigue symptom could improve the quality of life, and fatigue score in them. Therefore, the investigators planned to compare the efficacy of L-carnitine and placebo in hypothyroid patients who had taken levothyroxine.
Safety and Efficacy of Empiric Levothyroxine (LT4) Dose Increase Versus Individualized LT4 Dose...
Pregnancy RelatedThyroidIn women who require thyroid hormone replacement medication, the investigators will compare 2 ways to adjust thyroid medication during pregnancy to determine superiority in maintaining optimal blood levels of thyroid hormone. Thyroid hormone requirements increase significantly in pregnancy and it is important that blood levels of thyroid hormone remain normal so the fetus, which cannot make its own thyroid hormone has enough for early prenatal development. This trial compares 2 methods for adjusting thyroid medicine during pregnancy in women with known thyroid disease. Pregnant women (age 18 to 45) who take thyroid medication will be randomized to either 1) a 2-dose per week increase in thyroid medicine once pregnancy is confirmed, followed by dose adjustments every 2-4 weeks, or 2) adjustments in thyroid medication every 2-4 weeks in micrograms per day based on results of blood tests. The investigators will compare thyroid hormone levels throughout pregnancy between the groups of mothers to determine which method is superior in meeting the increased thyroid hormone requirements during pregnancy.
Iron Deficiency Anemia Can be an Indication for Treatment of Subclinical Hypothyroidism
Iron Deficiency AnemiaSubclinical HypothyroidismTo determine whether iron deficiency anemia can be an indication for the treatment of subclinical hypothyroidism.
Phase 4 Study in Secondary Hypothyroidism: Body Weight Adapted Thyroxin Treatment and Triiodothyronine...
Secondary HypothyroidismHypopituitarism1 moreThe purpose of this study is to determine whether a body weight adjusted dose of thyroxin is superior to treatment guided by laboratory results of thyroxin hormones in patients with central hypothyroidism. Moreover beneficial effects of triiodthyronine supplementation are investigated.
Comorbidities Resolution After MGB Surgery and Change in Body Composition
Morbid ObesityType2diabetes6 moreThis observational study aims to learn about the correlation between the improving comorbidities associated with obesity after MGB (Mini-Gastric Bypass) surgery and changes in body composition in morbidly obese patients. The main questions it aims to answer are: To study the correlation between the improving comorbidities associated with obesity after MGB(Mini-Gastric Bypass) surgery and changes in body composition. Other objectives are: Changes in the parameters of the metabolic syndrome after surgery Changes in the cardiovascular risk biomarkers after metabolic surgery Emergence in complications arising out of surgery requiring any intervention or causing a prolonged hospital stay, or requiring additional outpatient visits. Type of Study: An observational study in which participants with morbid obesity will undergo mini-gastric bypass surgery as per routine protocol. No separate experimental interventions will be done in the study for the participants.