Thyroid nodules are a common clinical problem, and differentiated thyroid cancer is becoming increasingly prevalent. Since the American Thyroid Association's (ATA's) guidelines for the management of ...these disorders were revised in 2009, significant scientific advances have occurred in the field. The aim of these guidelines is to inform clinicians, patients, researchers, and health policy makers on published evidence relating to the diagnosis and management of thyroid nodules and differentiated thyroid cancer.
The specific clinical questions addressed in these guidelines were based on prior versions of the guidelines, stakeholder input, and input of task force members. Task force panel members were educated on knowledge synthesis methods, including electronic database searching, review and selection of relevant citations, and critical appraisal of selected studies. Published English language articles on adults were eligible for inclusion. The American College of Physicians Guideline Grading System was used for critical appraisal of evidence and grading strength of recommendations for therapeutic interventions. We developed a similarly formatted system to appraise the quality of such studies and resultant recommendations. The guideline panel had complete editorial independence from the ATA. Competing interests of guideline task force members were regularly updated, managed, and communicated to the ATA and task force members.
The revised guidelines for the management of thyroid nodules include recommendations regarding initial evaluation, clinical and ultrasound criteria for fine-needle aspiration biopsy, interpretation of fine-needle aspiration biopsy results, use of molecular markers, and management of benign thyroid nodules. Recommendations regarding the initial management of thyroid cancer include those relating to screening for thyroid cancer, staging and risk assessment, surgical management, radioiodine remnant ablation and therapy, and thyrotropin suppression therapy using levothyroxine. Recommendations related to long-term management of differentiated thyroid cancer include those related to surveillance for recurrent disease using imaging and serum thyroglobulin, thyroid hormone therapy, management of recurrent and metastatic disease, consideration for clinical trials and targeted therapy, as well as directions for future research.
We have developed evidence-based recommendations to inform clinical decision-making in the management of thyroid nodules and differentiated thyroid cancer. They represent, in our opinion, contemporary optimal care for patients with these disorders.
Abstract
Background
The brain is a critical target organ for thyroid hormone, but it is unclear whether variations in thyroid function within and near the reference range affect quality of life, ...mood, or cognition.
Methods
A total of 138 subjects with levothyroxine (L-T4)-treated hypothyroidism and normal thyrotropin (TSH) levels underwent measures of quality of life (36-Item Short Form Health Survey, Underactive Thyroid-Dependent Quality of Life Questionnaire), mood (Profile of Mood States, Affective Lability Scale), and cognition (executive function, memory). They were then randomly assigned to receive an unchanged, higher, or lower L-T4 dose in double-blind fashion, targeting one of three TSH ranges (0.34 to 2.50, 2.51 to 5.60, or 5.61 to 12.0 mU/L). Doses were adjusted every 6 weeks based on TSH levels. Baseline measures were reassessed at 6 months.
Results
At the end of the study, by intention to treat, mean L-T4 doses were 1.50 ± 0.07, 1.32 ± 0.07, and 0.78 ± 0.08 μg/kg (P < 0.001), and mean TSH levels were 1.85 ± 0.25, 3.93 ± 0.38, and 9.49 ± 0.80 mU/L (P < 0.001), respectively, in the three arms. There were minor differences in a few outcomes between the three arms, which were no longer significant after correction for multiple comparisons. Subjects could not ascertain how their L-T4 doses had been adjusted (P = 0.55) but preferred L-T4 doses they perceived to be higher (P < 0.001).
Conclusions
Altering L-T4 doses in hypothyroid subjects to vary TSH levels in and near the reference range does not affect quality of life, mood, or cognition. L-T4-treated subjects prefer perceived higher L-T4 doses despite a lack of objective benefit. Adjusting L-T4 doses in hypothyroid patients based on symptoms in these areas may not result in significant clinical improvement.
L-T4 doses were adjusted in hypothyroid subjects to achieve low-normal, high-normal, or mildly elevated TSH levels. No effects were seen in quality of life, mood, or cognition after 6 months.
Thyrotropin (TSH)-suppressive doses of levothyroxine (LT4) have adverse effects on bone and cardiac function, but it is unclear whether metabolic function is also affected. The objective of this ...study was to determine whether women receiving TSH-suppressive LT4 doses have alterations in energy expenditure or body composition.
This study was a cross-sectional comparison between three groups of women: 26 women receiving chronic TSH-suppressive LT4 doses, 80 women receiving chronic replacement LT4 doses, and 16 untreated euthyroid control women. Subjects underwent measurements of resting energy expenditure (REE), substrate oxidation, and thermic effect of food by indirect calorimetry; physical activity energy expenditure by accelerometer; caloric intake by 24-hour diet recall; and body composition by dual X-ray absorptiometry.
REE per kilogram lean body mass in the LT4 euthyroid women was 6% lower than that of the LT4-suppressed group, and 4% lower than that of the healthy control group (p = 0.04). Free triiodothyronine (fT3) levels were directly correlated with REE, and were 10% lower in the LT4 euthyroid women compared with the other two groups (p = 0.007). The groups of subjects did not differ in other measures of energy expenditure, caloric intake, or body composition.
LT4 suppression therapy does not adversely affect energy expenditure or body composition in women. However, LT4 replacement therapy is associated with a lower REE, despite TSH levels within the reference range. This may be due to lower fT3 levels, suggesting relative tissue hypothyroidism may contribute to impaired energy expenditure in LT4 therapy.
It is unclear whether variations in thyroid status within or near the reference range affect energy expenditure, body mass, or body composition.
138 subjects treated with levothyroxine (LT4) for ...hypothyroidism with normal TSH levels underwent measurement of total, resting, and physical activity energy expenditure; thermic effect of food; substrate oxidation; dietary intake; and body composition. They were assigned to receive an unchanged, higher, or lower LT4 dose in randomized, double-blind fashion, targeting one of three TSH ranges (0.34 to 2.50, 2.51 to 5.60, or 5.61 to 12.0 mU/L). The doses were adjusted every 6 weeks to achieve target TSH levels. Baseline measures were reassessed at 6 months.
At study end, the mean LT4 doses and TSH levels were 1.50 ± 0.07, 1.32 ± 0.07, and 0.78 ± 0.08 µg/kg (P < 0.001) and 1.85 ± 0.25, 3.93 ± 0.38, and 9.49 ± 0.80 mU/L (P < 0.001), respectively, in the three arms. No substantial metabolic differences in outcome were found among the three arms, although direct correlations were observed between decreases in thyroid status and decreases in resting energy expenditure for all subjects. The subjects could not ascertain how their LT4 dose had been adjusted but the preferred LT4 dose they perceived to be higher (P < 0.001).
Altering LT4 doses in subjects with hypothyroidism to vary TSH levels in and near the reference range did not have major effects on energy expenditure or body composition. Subjects treated with LT4 preferred the perceived higher LT4 doses despite a lack of objective effect. Our data do not support adjusting LT4 doses in patients with hypothyroidism to achieve potential improvements in weight or body composition.
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.
Abstract
Purpose:
It is not clear whether upper limits of the thyrotropin (TSH) reference range should be lowered. This debate can be better informed by investigation of whether variations in thyroid ...function within the reference range have clinical effects. Thyroid hormone plays a critical role in determining energy expenditure, body mass, and body composition, and therefore clinically relevant variations in these parameters may occur across the normal range of thyroid function.
Methods:
This was a cross-sectional study of 140 otherwise healthy hypothyroid subjects receiving chronic replacement therapy with levothyroxine (L-T4) who had TSH levels across the full span of the laboratory reference range (0.34 to 5.6 mU/L). Subjects underwent detailed tests of energy expenditure (total and resting energy expenditure, thermic effect of food, physical activity energy expenditure), substrate oxidation, diet intake, and body composition.
Results:
Subjects with low-normal (≤2.5 mU/L) and high-normal (>2.5 mU/L) TSH levels did not differ in any of the outcome measures. However, across the entire group, serum free triiodothyronine (fT3) levels were directly correlated with resting energy expenditure, body mass index (BMI), body fat mass, and visceral fat mass, with clinically relevant variations in these outcomes.
Conclusions:
Variations in thyroid function within the laboratory reference range have clinically relevant correlations with resting energy expenditure, BMI, and body composition in L-T4–treated subjects. However, salutary effects of higher fT3 levels on energy expenditure may be counteracted by deleterious effects on body weight and composition. Further studies are needed before these outcomes should be used as a basis for altering L-T4 doses in L-T4–treated subjects.
In hypothyroid subjects receiving L-T4 therapy with normal TSH levels, fT3 levels were directly correlated with BMI, body adiposity, and resting, but not total, energy expenditure.
There has been recent debate within the thyroid field regarding whether current upper limits of the thyrotropin (TSH) reference range should be lowered. This debate can be better informed by ...investigation of whether variations in thyroid function within the reference range have clinical effects. One important target organ for thyroid hormone is the brain, but little is known about variations in neurocognitive measures within the reference range for thyroid function.
This was a cross-sectional study of 132 otherwise healthy hypothyroid subjects receiving chronic replacement therapy with levothyroxine (LT4) who had TSH levels across the full span of the laboratory reference range (0.34-5.6 mU/L). Subjects underwent detailed tests of health status, mood, and cognitive function, with an emphasis on memory and executive functions.
Subjects with low-normal (≤2.5 mU/L) and high-normal (>2.5 mU/L) TSH levels did not differ on most tests of health status, mood, or cognitive function, and there were no correlations between TSH, free T4, or free T3 levels and most outcomes. There was, however, a suggestion that thyroid function affected performance on the Iowa Gambling Task, which mimics real life decision-making. Subjects with low-normal TSH levels made more advantageous decisions than those with high-normal TSH levels.
Variations in thyroid function within the laboratory reference range do not appear to have clinically relevant effects on health status, mood, or memory in LT4 treated subjects. However, decision making, which encompasses many executive functions, may be affected. Unless further studies strengthen this finding, these data do not support narrowing the TSH reference range.
(1) To investigate the role of chronic lymphocytic thyroiditis (CLT) in central node metastasis of papillary thyroid carcinoma (PTC) and (2) to evaluate the presence of chronic lymphocytic ...thyroiditis according to PTC-specific molecular markers.
Historical cohort study.
Academic medical center.
All patients who underwent total thyroidectomy with central neck dissection for PTC at Oregon Health & Science University between 2005 and 2010 were screened for the presence of CLT and reviewed for clinical prognostic factors. Patients with inadequate central neck dissections were excluded. Molecular markers for PTC were analyzed on archived tumor samples.
A total of 139 patients met selection criteria. The rate of CLT was 43.8%. The rate of central node positivity was 63%. Presence of CLT was associated with a significantly lower proportion of central node metastases (49% vs 74%, P = .003) and angiolymphatic invasion (31% vs 15%, P = .03). There was no significant difference in mean age, tumor size, and extracapsular extension. Molecular genotyping did not reveal a significant difference in the types of mutations found in both groups.
The data indicate a lower incidence of central compartment lymph node metastasis in those with CLT in this patient population, suggesting a potential protective role in tumor spread. The equal distribution of tumor mutations between the carcinomas with and without evidence of CLT argues against a mutation-specific antigen as the immunologic stimulus. Further research is needed to characterize the role of autoimmunity in thyroid cancer.
In 2000, the National Center for Research Resources mandated that general research centers create a research subject advocate (RSA) position. In 2008, the Clinical and Translational Science Award ...(CTSA) consortium endorsed a new advocacy model based on four RSA Best Practice Functions. The authors surveyed CTSA centers to learn about their implementation of programs to fulfill the RSA functions.
In 2010, the RSA taskforce developed a two-part online survey to examine leadership, organizational structure, governance, scope, collaboration and integration, and funding and evaluation of RSA activities implemented at CTSA centers.
Respondents from 45 RSA programs at 43 CTSA centers completed the survey. Senior university or CTSA officials led all programs. Ninety-six percent (43/45) of programs were funded by a CTSA core. Eighty percent (36/45) designated an individual "RSA." Ninety-eight percent (44/45) provided diverse services either in collaboration with or complementary to other departments, including development of data and safety monitoring plans (16/45; 36%), informed consent observation (10/45; 22%), training responsive to audit findings (12/45; 27%), and direct advocacy services to participants (11/45; 24%). Eighty-six percent (24/28) reported qualitative evaluation methods for these activities.
RSA programs conduct both collaborative and unique research protection activities. This survey, an initial step in developing a more robust mechanism for evaluating RSA programs, collected valuable feedback. The authors recommend defining and developing outcome-based evaluation measures that take the heterogeneity of the individual RSA programs into account while advancing their value and effectiveness in protecting human research subject participants.
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