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Serum Thyroid-stimulating Hormone (serum + thyroid-stimulating_hormone)
Selected AbstractsPituitary and autonomic responses to cold exposures in manACTA PHYSIOLOGICA, Issue 4 2005J. Leppäluoto Abstract This review presents hormonal responses to various cold exposures and their calorigenic effects in man and some animals. Previous studies in rats have shown that cold exposures activate the hypothalamic-pituitary-thyroid axis. Increased thyroid hormone concentrations lead to heat production via general stimulation of metabolism (obligatory thermogenesis) and possibly via activation of thyroid hormone receptors and uncoupling protein 1 (UCP 1) and deiodinase enzyme genes in the brown adipose tissue (BAT). In human subjects long-term cold exposures do not seem to activate the pituitary-thyroid axis, but rather accelerate the elimination of triiodothyronine (T3), leading to low serum concentrations of free T3 hormone. In corollary to this a hypothyreotic condition with increased serum thyroid-stimulating hormone and impaired mood and cognitive performance can be observed after long-term cold exposures such as wintering. During cold exposures the sympathetic nerve system is activated and noradrenaline is released to blood circulation and to BAT, where it leads to production of cAMP, lipolysis and free fatty acids. Free fatty acids open the mitochondrial proton channel protein in BAT. Protons enter the mitochondria and inhibit ATP synthesis (uncoupling). By this way energy is transformed into heat (facultatory or adaptive thermogenesis). In adult human subjects the amount of BAT is small and adaptive thermogenesis (non-shivering thermogenesis) has a smaller role. UCP 1 with other uncoupling proteins may have other functions in the control of body weight, sugar balance and formation of reactive oxygen species. [source] Depressive relapse during lithium treatment associated with increased serum thyroid-stimulating hormone: results from two placebo-controlled bipolar I maintenance studiesACTA PSYCHIATRICA SCANDINAVICA, Issue 1 2009M. A. Frye Objective:, To assess the relationship between depressive relapse and change in thyroid function in an exploratory post hoc analysis from a controlled maintenance evaluation of bipolar I disorder. Method:, Mean thyroid-stimulating hormone (TSH) and outcome data were pooled from two 18-month, double-blind, placebo-controlled, maintenance studies of lamotrigine and lithium monotherapy. A post hoc analysis of 109 subjects (n = 55 lamotrigine, n = 32 lithium, n = 22 placebo) with serum TSH values at screening and either week 52 (±14 days) or study drop-out was conducted. Results:, Lithium-treated subjects who required an intervention for a depressive episode had a significantly higher adjusted mean TSH level (4.4 ,IU/ml) compared with lithium-treated subjects who did not require intervention for a depressive episode (2.4 ,IU/ml). Conclusion:, Lithium-related changes in thyroid function are clinically relevant and should be carefully monitored in the maintenance phase of bipolar disorder to maximize mood stability and minimize the risk of subsyndromal or syndromal depressive relapse. [source] Incidence of iodine deficiency in Turkish patients with congenital hypothyroidismPEDIATRICS INTERNATIONAL, Issue 3 2008Olcay Evliyao Abstract Background: Turkey is located in an area of mild to moderate iodine deficiency. The aim of the present study was to investigate the incidence of iodine deficiency in patients with congenital hypothyroidism. Methods: Twenty five patients with a median age of 12 days (6 days,6 months) at diagnosis and followed for a median time of 7 months (1,60 months) were enrolled in the study. Thyroid function tests, thyroid scintigraphy, ultrasonography and urine iodine measurements of the patients and mothers were performed. Results and conclusion: Congenital hypothyroidism was diagnosed within postnatal day 13, between days 13 and 30, and after 30 days of age in 68%, 20% and 12% of the patients, respectively. At the time of diagnosis mean serum thyroid-stimulating hormone and total T4 were 85.3 ± 27.6 mIU/L and 3.9 ± 2.8 ,g/dL, respectively. Incidence of iodine deficiency was 36% in the patients (median, 110 ,g/L) and 88% in the mothers (median, 40 ,g/L). Thyroid scintigraphy and ultrasound were normal in all of the patients with iodine deficiency. At scintigraphic evaluation, thyroid gland was not visualized in 28% of patients; in the patients whose thyroid glands were not visualized scintigraphically thyroid ultrasonography indicated agenesis in 57%, and hypoplasia in 43%. In all the patients with thyroid agenesis or hypoplasia iodine levels were normal. In 36% of the patients imaging studies of thyroid gland and urine iodine measurements were normal. Despite salt iodization program, incidence of iodine deficiency is still high in patients with congenital hypothyroidism and mothers. National measures are urgently required for correction of iodine deficiency in Turkey. [source] Health-Related Quality-of-Life Study in Patients With Carcinoma of the Thyroid After Thyroxine Withdrawal for Whole Body ScanningTHE LARYNGOSCOPE, Issue 11 2006Sin-Ming Chow FRCR Abstract Objectives/Hypothesis: The authors studied the change of health-related quality of life (HR-QOL) in patients with differentiated thyroid carcinoma (DTC) with thyroxine (T4) withdrawal in preparation for whole body radioactive iodine scanning. Study Design: Seventy-eight patients with DTC and history of radioactive iodine (RAI) ablation were prospectively recruited. They completed the Functional Assessment of Cancer Treatment-General (FACT-G) questionnaire on weeks 0, 2, and 4 after T4 withdrawal with corresponding checking of serum thyroid-stimulating hormone (TSH). Results: Overall, 74.5% (58 of 78) of patients completed all FACT-G. Comparing FACT-G scores at weeks 0 and 4, "physical" (P < .001), "social" (P = .04), and "emotional" (P = .047) aspects were lowered as well as "total" HR-QOL (P = .001). However, the "functional" domain of HR-QOL was not affected (P = .14). Comparing FACT-G scores at week 0 and 2, we found that "physical" (P = .049) and "total" (P = .05) HR-QOL were affected early (in the first 2 weeks) in T4 withdrawal. Comparison of week 2 and 4 showed that in the later half of the withdrawal period, "physical" (P = .001), "emotional" (P = .02), and "total" FACT-G scores (P = .002) were affected. Mean TSH level (in mIU/L) increased gradually: 2.8 (week 0), 42.8 (week 2), 97 (week 3), and 153 (week 4). The percentage of patients attaining TSH level of >30 mIU/L were 55% (week 2), 96.2% (week 3), and 100% (week 4). Conclusions: HR-QOL declines with time of T4 withdrawal. The impact is more severe in the later period of T4 withdrawal. In 3 weeks, 96.2% of our patients attained TSH level of 30 mIU/L. To minimize the impact on HR-QOL, duration of T4 withdrawal can be decreased to 3 weeks. [source] | ||||||||||