Hypothyroidism

1. To evaluate the effect of a medication adherence-based digital intervention on fatigue severity in patients with hypothyroidism. 2. To assess the effect of a medication adherence-based digital intervention on weight in patients with hypothyroidism. 3. To investigate the effect of a medication adherence-based digital intervention on thyroid hormone regulation in patients with hypothyroidism.

Hypothyroidism is a common condition, more frequent in females, associated with excess of cardiovascular risk and poor quality of life not completely abrogated by treatment with levothyroxine. There is an unmet need to define a safe, effective, and feasible regimen to be applied in large trials aimed at assessing levothyroxine/liothyronine combination therapy in patients living with hypothyroidism. To address this knowledge gap we propose a randomized, three-arm, double-blind, controlled, escalating dose parallel pilot study whose results will lay the foundation of large multicenter trial(s) able to demonstrate the effectiveness (or lack thereof) of levothyroxine/liothyronine combination therapy.

Our overall goal is to determine the clinical consequences of allowing greater flexibility in LT4 dosing in older individuals who take LT4.

This 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.

The goal of this study is to find out whether hypothyroidism caused by immune checkpoint inhibitors (ICIs) can recover after stopping the ICIs. The study also aims to identify factors that can help predict which patients will be able to stop taking thyroid hormone replacement. The main questions the study will answer are: * What percentage of patients recover normal thyroid function and can stop levothyroxine after stopping ICIs? * What clinical or laboratory factors can predict successful withdrawal of levothyroxine? Participants will: * Be adult cancer patients who developed hypothyroidism during ICI treatment and are currently taking levothyroxine * Have already stopped ICI therapy * Gradually reduce their levothyroxine dose every 3 months if their thyroid function remains normal * Stop levothyroxine if thyroid function remains normal at low doses (≤0.025 mg) * Be monitored with thyroid function tests and clinical symptoms at each visit

The proposed study focuses on testing a novel adapted evidence-based multilevel intervention, Deprescribing Thyroid Hormone In Older Adults (D-THIO), to support thyroid hormone deprescribing (dose de-escalation and/or discontinuation) in older adults with thyroid hormone overtreatment and/or misuse and reduce patient harm. Findings from this study will lay the groundwork for broad implementation of D-THIO and serve as a model for deprescribing inappropriate medications for other endocrine conditions and conditions with biochemical monitoring.

This study will evaluate the efficacy and safety of Armour Thyroid treatment compared with synthetic T4 in subjects who have primary hypothyroidism and are currently stabilized (i.e., in-range thyroid-stimulating hormone \[TSH\]) on synthetic T4 treatment. This study will also therefore evaluate the efficacy and safety of dose conversion from synthetic T4 therapy to Armour Thyroid therapy.

Hypothyroidism is a thyroid disorder and one of the most common endocrine disorders. Hypothyroidism can have multiple causes; most patients suffer from primary autoimmune hypothyroidism (Hashimoto's disease), but also central hypothyroidism, hypothyroidism after total thyroidectomy due to thyroid carcinoma, or hypothyroidism due to therapy of Graves' disease occur. Most patients with hypothyroidism are treated with levothyroxine (L-T4) to supplement the lack of thyroxine (T4) produced by their own thyroid. Serum thyroid-stimulating hormone (TSH) and/or free T4 (fT4) are currently measured to assess the efficacy of this therapy and to establish euthyroidism. It is known that fT4 concentrations in patients using L-T4 can be above the upper limit of the reference interval, while their TSH is not (completely) suppressed. This raises the question whether fT4 is an accurate reflection of thyroid hormone status in patients using L-T4. TSH is considered a reliable parameter of thyroid hormone status; however, TSH cannot be used to assess thyroid function in specific hypothyroid patient groups (e.g. central hypothyroidism). Free triiodothyronine (fT3), the active thyroid hormone, has been suggested to be an interesting alternative of fT4 to assess thyroid function. Previously, the methods to measure fT3 were not that robust; however, methods to determine fT3 have been improved, are currently reliable and not susceptible to changes due to L-T4 intake. In addition, the fT3/fT4 ratio is thought to be an interesting candidate in assessing thyroid hormone status as well. The aim of this study is to improve laboratory diagnostics of thyroid hormone status in patients with hypothyroidism receiving L-T4 in whom TSH cannot be used as a reflection of thyroid hormone status. We will primarily investigate the additional already available laboratory tests fT3 and fT3/fT4 ratio. We hypothesize that treated hypothyroid participants who are assumed euthyroid based on TSH (e.g. patients with Hashimoto's hypothyroidism) but have fT4 concentrations above the upper reference limit will more often have a fT3 level or a fT3/fT4 ratio within the reference interval. Concentrations of alternative markers in healthy controls and patients with Hashimoto's hypothyroidism with 'normal' TSH concentrations can, thus, be used to predict thyroid hormone status in patients using L-T4 in whom TSH cannot be used to assess thyroid hormone status.

Women with hypothyroidism often report persistent fatigue, weight gain, autonomic dysregulation, and stress despite stable levothyroxine therapy. This single-center, parallel-group RCT will test whether a structured, supervised 12-week walking program improves basal metabolic rate (BMR) and psychophysiological outcomes compared with usual activity. One hundred twenty women aged 35-55 with stable primary hypothyroidism will be randomized 1:1 to intervention or control.

This study will be conducted to compare between the effect of nonlinear and linear periodized training on quality of life in females with hypothyroidism.

Levothyroxine is the most used thyroid hormone replacement when the thyroid gland is failing. Because dosage adjustment normally takes several months, the investigators have developed a decision support tool (DST) that predicts optimal dosage based on repeated blood samples the first 2 weeks after initiation of therapy. In this randomized study the investigators will include patients that start levothyroxine therapy after total thyroidectomy. The use of DST to advice the physician about an early dosage adjustment will be compared with common clinical practice, that is dosage adjustment every 2 months. The effect of DST use will be assessed by studying the possible relationship between fast optimal dose adjustment, patient reported outcome measures, and ability to work.

Hypothyroidism, defined by elevated thyrotropin (TSH) levels, is a common endocrine complication in chronic kidney disease patients, and prior evidence shows that higher TSH levels, even within the normal laboratory range, are strongly associated with impaired quality of life and cardiovascular disease in this population. Levothyroxine is one of the most frequently prescribed medications in chronic kidney disease, yet its efficacy and safety in these patients have not been well-studied. Hence, this study will investigate 1) whether levothyroxine improves patient-centered (e.g., health-related quality of life, physical performance, strength) and 2) cardiovascular (e.g., coronary artery calcification, endothelial function, systolic function) outcomes in dialysis patients, and 3) if thyroid hormone replacement exerts classic metabolic effects (i.e., changes in body fat and resting energy expenditure) in this population.

This is a longitudinal retrospective study for the evaluation of thyroid function and structure in patients with Klinefelter syndrome compared to healthy controls and patients affected by chronic lymphocytic thyroiditis.

Observational single-center prospective and retrospective, nonpharmacological, spontaneous cohort study.

Aortic stenosis is highly prevalent in advancing age. The prognosis of this disease has dramatically changed with the surgical replacement of the aortic valve and the trans catheter aortic valve re-placement (TAVI). The TAVI procedure is also successful in octogenarians and frail patients. However, the evaluation before the TAVI procedure requires a high dosage of iodinated contrast agent with, consequently, an increased risk for thyroid dysfunction. The primary endpoint of this study is to assess, prospectively, the incidence and the predictive factors (underlying thyroid disease, medication, food preservative, topical antiseptics) of hypothyroidism after a TAVI procedure. The secondary endpoint is the influence of the occurrence of hypothyroidism after the TAVI procedure on the geriatric assessment.

Thyroid hormones (TH) play a pivotal role in the development and function of the mammalian brain. Patients with impaired thyroid hormone transport into the brain tissue or in the case of defective local thyroid hormone receptor (collectively referred to as thyroid hormone resistance) subsequently experience psychomotor disabilities. The "DEEPTYPE" registry has been established with the objective of intensifying the genotyping and, in particular, the neurological phenotyping of patients exhibiting deficiencies in either the thyroid hormone transporter (MCT8) or the thyroid hormone receptor alpha (THRα). The objective of this registry-based study is to enhance the diagnostic yield for MCT8 and THRα deficiencies by employing the serum fT3/fT4 ratio as a more sophisticated screening parameter. Furthermore, the investigators will study the genomic regulation of both genes and attempt to identify further coding and non-coding mutations that result in TH resistance. The patient registry "DEEPTYPE" will document the retrospective and prospective clinical data of identified children in a comprehensive manner. This will enable the identification of three key groups: (i) patients with non-coding mutations, (ii) patients with milder phenotypes presenting only with a subset of symptoms seen in both "classic" conditions, and (iii) patients who are ready for clinical trials.