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Effect of recombinant human thyroid-stimulating hormone or levothyroxine withdrawal on salivary gland dysfunction after radioactive iodine administration for thyroid remnant ablation.
Iakovou, I, Goulis, DG, Tsinaslanidou, Z, Giannoula, E, Katsikaki, G, Konstantinidis, I
Head & neck. 2016;:E227-30
Abstract
BACKGROUND The purpose of this study was to examine the incidence of sialadenitis and xerostomia within a year after radioactive iodine administration for thyroid remnant ablation after preparation with recombinant human thyroid-stimulating hormone (rhTSH) or levothyroxine (LT4 ) withdrawal. METHODS The study has included 121 patients, divided into 4 groups: group A (rhTSH = 100 mCi), group B (rhTSH = 70 mCi), group C (LT4 withdrawal = 100 mCi), and group D (LT4 withdrawal = 70 mCi). Study outcomes were Summated Xerostomia Inventory score and number of sialadenitis episodes after radioactive iodine administration. RESULTS Salivary gland dysfunction was reported in 31% and 12% of patients, at the end of months 1 and 12, respectively. There was significantly lower incidence in groups A and B in comparison with groups C and D (p = .002 and .021, respectively). CONCLUSION The use of rhTSH for preparation of radioactive iodine ablation as opposed to LT4 withdrawal reduces the incidence of salivary gland dysfunction. © 2015 Wiley Periodicals, Inc. Head Neck 38: E227-E230, 2016.
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The effects of levothyroxine replacement or suppressive therapy on health status, mood, and cognition.
Samuels, MH, Kolobova, I, Smeraglio, A, Peters, D, Janowsky, JS, Schuff, KG
The Journal of clinical endocrinology and metabolism. 2014;(3):843-51
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Abstract
CONTEXT TSH-suppressive doses of levothyroxine (L-T4) have adverse effects on bone and cardiac function, but it is unclear whether central nervous system function is also affected. OBJECTIVE The aim of the study was to determine whether women receiving TSH-suppressive L-T4 doses have decrements in health status, mood, or cognitive function. DESIGN AND SETTING A cross-sectional comparison was made among three groups of women in an academic medical center research clinic. PATIENTS Twenty-four women receiving chronic TSH-suppressive L-T4 doses, 35 women receiving chronic replacement L-T4 doses, and 20 untreated control women participated in the study. INTERVENTIONS Subjects underwent testing at a single outpatient visit. MAIN OUTCOME MEASURES We measured health status (SF-36), mood (Profile of Mood States, Symptom Checklist 90-R, Affective Lability Scale), and cognitive function (declarative memory [Paragraph Recall], working memory [N-back, Subject Ordered Pointing], motor learning [Pursuit Rotor, Motor Sequence Learning Test], and executive function [Letter Cancellation Test, Trail Making Test, Iowa Gambling Test]). RESULTS Women receiving TSH-suppressive or replacement L-T4 doses had decrements in health status and mood compared to healthy controls. These decrements were more pronounced in women receiving replacement, rather than suppressive, L-T4 doses. Memory and executive function were not affected in either treated group, compared to healthy controls. CONCLUSIONS Women receiving TSH-suppressive doses of L-T4 do not have central nervous system dysfunction due to exogenous subclinical thyrotoxicosis, but TSH-suppressed and L-T4-replaced women have slight decrements in health status and mood that may be related to self-knowledge of the presence of a thyroid condition or other uncharacterized factors. These mood alterations do not impair cognitive function.
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High circulating thyrotropin levels in obese women are reduced after body weight loss induced by caloric restriction.
Kok, P, Roelfsema, F, Langendonk, JG, Frölich, M, Burggraaf, J, Meinders, AE, Pijl, H
The Journal of clinical endocrinology and metabolism. 2005;(8):4659-63
Abstract
CONTEXT Previous clinical studies concerning the impact of body weight loss on single plasma TSH concentration measurements or the TSH response to TRH in obese humans have shown variable results. OBJECTIVE The objective of this study was to investigate the effect of weight loss induced by caloric restriction on diurnal TSH concentrations and secretion in obese humans. DESIGN This was a clinical, prospective, crossover study. SETTING The study was conducted at the Clinical Research Center of Leiden University Medical Center. PARTICIPANTS Eleven obese premenopausal women (body mass index, 33.3 +/- 0.7 kg/m2) were studied. INTERVENTION The study intervention was weight loss (50% reduction overweight by caloric restriction). MAIN OUTCOME MEASURE(S): Twenty-four-hour plasma TSH concentrations (10-min intervals) and the 24-h TSH secretion rate, calculated by a waveform-independent deconvolution technique (Pulse), were determined. RESULTS The 24-h TSH secretion rate was significantly higher in obese women than in normal weight controls, and weight loss was accompanied by diminished TSH release (before weight loss, 43.4 +/- 6.4 mU/liter.24 h; after weight loss, 34.4 +/- 5.9 mU/liter.24 h; P = 0.02). Circulating free T3 levels decreased after weight loss from 4.3 +/- 0.19 to 3.8 +/- 0.14 pmol/liter (P = 0.04). Differences in 24-h TSH release correlated positively with the decline of circulating leptin (r2 = 0.62; P < 0.01). CONCLUSIONS Elevated TSH secretion in obese women is significantly reduced by diet-induced weight loss. Among various physiological cues, leptin may be involved in this phenomenon. The decreases in TSH and free T3 may blunt energy expenditure in response to long-term calorie restriction, thereby frustrating weight loss attempts of obese individuals.
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Dosimetry of radioiodine therapy in patients with nodular goiter after pretreatment with a single, low dose of recombinant human thyroid-stimulating hormone.
Nieuwlaat, WA, Hermus, AR, Ross, HA, Buijs, WC, Edelbroek, MA, Bus, JW, Corstens, FH, Huysmans, DA
Journal of nuclear medicine : official publication, Society of Nuclear Medicine. 2004;(4):626-33
Abstract
UNLABELLED A single, low dose of recombinant human thyroid-stimulating hormone (rhTSH) doubles 24-h RAIU and causes a more homogeneous distribution of radioiodine on thyroid scintigrams of patients with nodular goiter. Pretreatment with rhTSH allows the therapeutic dose of (131)I to be reduced by 50%-60% without compromising the result of thyroid volume reduction. The present study focused on the dosimetric aspects of therapy with a reduced dose of (131)I after pretreatment with rhTSH in patients with nodular goiter. METHODS Thirty-six patients were treated with (131)I to reduce thyroid volume. Nine patients were pretreated with a single dose of 0.01 mg of rhTSH, and 9 patients, with 0.03 mg of rhTSH. Two control groups of 9 patients, matched for thyroid weight and 24-h radioactive iodide uptake, were not pretreated with rhTSH. The therapeutic dose of (131)I was aimed at being sufficient to result in retention of 3.7 MBq of (131)I per gram of thyroid tissue at 24 h. Thyroid radioactivity after (131)I administration was measured every 24 h for 3 d and on days 7, 10, 14, 21, and 28. A model of iodine biokinetics was used to estimate absorbed doses in organs. Protein-bound (131)I activity was measured at 1, 2, 3, 7, and 10 d and at 2, 3, and 4 wk after (131)I therapy. RESULTS The administered activities were 1.5 times lower in the 0.01-mg rhTSH group and 1.9 times lower in the 0.03-mg rhTSH group than in the control groups. The absorbed dose in the thyroid was similar in the rhTSH-pretreated groups and in the control groups. In the organs of excretion (bladder) and uptake (stomach) of inorganic iodide, the absorbed doses were 2- to 3-fold lower in the pretreated groups than in the control groups. The effective dose equivalent outside the thyroid was considerably lower in the rhTSH-pretreated groups than in their respective control groups (1.6-fold in the 0.01-mg rhTSH group and 2.3-fold in the 0.03-mg rhTSH group). The time course of protein-bound (131)I activity in serum and the cumulated protein-bound (131)I activity in serum did not differ significantly between rhTSH-pretreated and control groups. CONCLUSION (131)I therapy after pretreatment with a single, low dose of rhTSH, with the dose reduced according to the rhTSH-induced increase in 24-h radioactive iodide uptake, caused lower radiation-absorbed doses in extrathyroidal organs and tissues, especially bladder and stomach, and no significant increase in the release of (131)I-labeled thyroid hormones into the circulation of patients with nodular goiter. Thus, this mode of therapy can be recommended, especially when the dose of radioiodine to be administered without rhTSH pretreatment is high.
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Rapid rise in serum thyrotropin concentrations after thyroidectomy or withdrawal of suppressive thyroxine therapy in preparation for radioactive iodine administration to patients with differentiated thyroid cancer.
Serhal, DI, Nasrallah, MP, Arafah, BM
The Journal of clinical endocrinology and metabolism. 2004;(7):3285-9
Abstract
Patients with differentiated thyroid cancer are often treated transiently with T(3) in preparation for radioactive iodine (RAI) therapy. We questioned the value of using T(3) transiently in patients requiring RAI therapy. Two groups of patients requiring RAI therapy were investigated. One group included patients studied immediately after thyroidectomy, whereas the other included those withdrawn from chronic suppressive T(4) therapy that followed thyroidectomy and postoperative RAI ablation. Serum TSH concentrations were serially measured two to three times weekly until they reached more than 30 mU/liter, after which RAI therapy was administered. Serum TSH concentrations reached more than 30 mU/liter 8-26 d (mean +/- sd, 14.2 +/- 4.8) after thyroidectomy or 9-29 (18.1 +/- 4.1) d after T(4) withdrawal. That level of TSH elevation was achieved 18 d after thyroidectomy and 22 d after T(4) withdrawal in more than 95% of patients. Minimal symptoms of hypothyroidism were noted in either group when RAI was administered. Serum TSH concentrations increased rapidly without transient therapy with T(3). To minimize symptoms of hypothyroidism, serum TSH levels should be measured twice weekly, starting 10 d after thyroidectomy or T(4) withdrawal. The data cast doubt about the value and benefits from using T(3) in preparing patients for RAI therapy.
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Hyperthyrotropinemia during iodide administration in normal children and in children born with neonatal transient hypothyroidism.
Markou, KB, Paraskevopoulou, P, Karaiskos, KS, Makri, M, Georgopoulos, NA, Iconomou, G, Mengreli, C, Vagenakis, AG
The Journal of clinical endocrinology and metabolism. 2003;(2):617-21
Abstract
The aim of the present study was to examine the effects of chronic iodide administration in pharmacological doses on thyroid function in children with a history of transient congenital hypothyroidism (TCH). We hypothesized that such children may carry a previously undisclosed intrinsic intrathyroidal defect, rendering them susceptible to TCH. We administered for this 60-65 mg iodide daily for 60 d in 13 individuals with TCH (group A), 8 of their siblings (group B), 8 healthy controls (group C), and 11 normal adults (group D). Thyroid function was evaluated by measuring serum T(3), T(4), free T(3), free T(4), TSH, and thyroglobulin concentrations and autoantibodies against thyroid peroxidase and thyroglobulin at baseline at 15, 30, and 60 d during iodide administration, and 2 months after iodide withdrawal. Hyperthyrotropinemia greater than 4.2 mU/liter but not higher than 10 mU/liter with normal thyroid hormone concentrations was observed in one of the TCH group and in two of the group B siblings. During iodide administration, hyperthyrotropinemia was observed in 8 of 13 (62%) adolescents in group A, 4 of 7 (57%) in group B, and 6 of 8 (75%) in group C. None of the 11 adults (group D) developed hyperthyrotropinemia during iodide administration. Serum T(4) and free T(4) concentrations were decreased in all groups when compared with baseline values. The magnitude of the decrease of serum T(4) was identical in all groups (0.7-0.8 microg/dl). Thyroid enlargement was observed in all subjects and was more pronounced in children. There were no cases of subclinical and/or overt hyperthyroidism. After iodine withdrawal, serum TSH decreased in all groups and returned to baseline levels, as well as the thyroid volume. In conclusion, the hypothalamic-pituitary-thyroid axis of adolescents with TCH responds to pharmacological doses of iodide similarly to that observed in normal children. The hyperthyrotropinemia observed in the adolescents exposed to iodides may reflect incipient transient hypothyroidism or simply a brisk TSH response to a small serum T(4) decrease. Whatever the mechanism, chronic use of excessive quantities of iodide should be avoided until the end of puberty.
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Ablation of thyroid residues with 30 mCi (131)I: a comparison in thyroid cancer patients prepared with recombinant human TSH or thyroid hormone withdrawal.
Pacini, F, Molinaro, E, Castagna, MG, Lippi, F, Ceccarelli, C, Agate, L, Elisei, R, Pinchera, A
The Journal of clinical endocrinology and metabolism. 2002;(9):4063-8
Abstract
The aim of the study was to assess whether stimulation by recombinant human TSH (rhTSH) may be used in patients with differentiated thyroid carcinoma for postsurgical ablation of thyroid remnants using a 30-mCi standard dose of (131)I during thyroid hormone therapy. The rate of ablation was prospectively compared in three groups of patients consecutively assigned to one of three treatment arms: in the first arm, patients (n = 50) were treated while hypothyroid (HYPO); in the second arm, patients (n = 42) were treated while HYPO and stimulated in addition with rhTSH (HYPO + rhTSH); in the third arm, patients (n = 70) were treated while euthyroid (EU) on thyroid hormone therapy and stimulated with rhTSH (EU + rhTSH). The outcome of thyroid ablation was assessed by conventional HYPO (131)I scan performed in HYPO state 6-10 months after ablation. Basal serum TSH was elevated in the HYPO and HYPO + rhTSH groups. In the EU + rhTSH group, basal serum TSH was 1.3 +/- 2.5 micro U/ml (range, <0.005-11.9 micro U/ml). After rhTSH, serum TSH significantly increased in the HYPO + rhTSH group and the EU + rhTSH group. Basal 24-h radioiodine thyroid bed uptake was 5.8 +/- 5.7% (range, 0.2-21%) and 5.4 +/- 5.7% (range, 0.2-26%) in the HYPO and HYPO + rhTSH groups, respectively. In the HYPO + rhTSH group, mean 24-h thyroid bed uptake rose to 9.4 +/- 9.5% (range, 0.2-46%) after rhTSH (P < 0.0001). The 24-h uptake after rhTSH in the EU + rhTSH group was 2.5 +/- 4.3% (range, 0.1-32%), significantly lower (P < 0.0001) than that found in the HYPO and HYPO + rhTSH groups. The rate of successful ablation was similar in the HYPO and HYPO + rhTSH groups (84% and 78.5%, respectively). A significantly lower rate of ablation (54%) was achieved in the EU + rhTSH group. Mean initial dose rate (the radiation dose delivered during the first hour after treatment) was significantly lower in the EU + rhTSH group (10.7 +/- 12.6 Gy/h) compared with the HYPO + rhTSH group (48.5 +/- 43 Gy/h) and the HYPO group (27.1 +/- 42.5 Gy/h). In conclusion, our study indicates that by using stimulation with rhTSH, a 30-mCi standard dose of radioiodine is not sufficient for a satisfactory thyroid ablation rate. Possible reasons for this failure may be the low 24-h radioiodine uptake, the low initial dose rate delivered to the residues, and the accelerated iodine clearance observed in EU patients. Possible alternatives for obtaining a satisfactory rate of thyroid ablation with rhTSH may consist of increasing the dose of radioiodine or using different protocols of rhTSH administration producing more prolonged thyroid cells stimulation.