CONTEXT Patients treated with levothyroxine typically ingest it in a fasting state to prevent food impairing its absorption. The serum thyrotropin concentration is the therapeutic index of levothyroxine action. OBJECTIVE The study objective was to determine the effect of the timing of levothyroxine administration in relationship to food on serum thyrotropin levels. DESIGN Participants were ...

Context The effect of thyrotropin (TSH) suppressive therapy on trabecular bone scores (TBSs) is unclear. Objective The aim of this study was to investigate the effect of TSH suppression on vertebral TBSs of postmenopausal women with differentiated thyroid carcinoma (DTC). Design, Setting, and Participants We conducted a retrospective cohort study including 273 postmenopausal women with DTC ...

Thyroid cancers of follicular cell origin (papillary and follicular cancers) are usually well differentiated and behave in a non-aggressive manner. However, some lose differentiated functions (dedifferentiation) and behave more aggressively. These cancers are or become refractor Re-differentiating agentsy to thyroid specific therapies that are based on differentiated thyroid function such as ra...

six to 8 weeks after the start of levothyroxine therapy you should reexamine patients and measure their serum thyroidstimulating hormone (TsH) (strength of recommendation [sor]: c, common practice and expert opinion). If thyroid function is normal at that time, examine the patient and measure serum TsH again in 4 to 6 months because clearance of levothyroxine increases in the euthyroid (normal)...

OBJECTIVE The impact of prolonged subclinical hyperthyroidism on glucose and lipid metabolism is unclear. Therefore, we evaluated glucose and lipid metabolism in patients with differentiated thyroid carcinoma (DTC) on TSH suppressive thyroxine therapy as a model for subclinical hyperthyroidism and investigated whether restoration to euthyroidism affects metabolism. DESIGN We performed a prosp...

Studies on the effects of levothyroxine (LT4) therapy on bone and bone metabolism have yielded conflicting results. This 1-year prospective study examined whether LT4 in patients with well-differentiated thyroid carcinoma (DTC) is a risk factor for bone mass loss and the subsequent development of osteoporosis. We examined 93 patients with DTC over 12months after initiating LT4 therapy (early po...

Although hypothyroidism is associated with an increased prevalence of psychiatric manifestations, myxedema madness is rarely observed. We report the case of a 62-year-old woman with no prior history of psychiatric disorders, who presented to the emergency department with psychomotor agitation 6 weeks after total thyroidectomy for papillary thyroid cancer. Serum thyroid stimulating hormone (TSH)...

INTRODUCTION The treatment-of-choice for differentiated thyroid carcinoma (DTC) is a total thyroidectomy with subsequent radioiodine therapy. In order to increase an iodine uptake in thyroid tissue remnants, the L-thyroxine withdrawal is required. It is recommended to achieve TSH levels higher than 25 mU/ml. As TSH is a known key factor in thyroid cell proliferation regulation, prolonged stimul...

BACKGROUND Nonadherence to levothyroxine therapy is one cause of persistent hypothyroidism. To distinguish nonadherence from malabsorption, a levothyroxine absorption test is required. Typically, this test measures the serum free thyroxine (FT4) response to 1000 mcg of oral levothyroxine over 4 to 24 hours. Published data indicate that serum levels of FT4 are at or near their peak 2 hours after...