Proposed Risk Stratification and Patterns of Radioactive Iodine Therapy in Malignant Struma Ovarii.

Introduction: Malignant struma ovarii (MSO) is a rare thyroid cancer arising within an ovarian teratoma. While surgical excision of the primary tumor is widely accepted as standard of care, recommendations for adjuvant treatment of MSO-whether or not to administer radioactive iodine (RAI)-are based largely on case reports and remain debated. In this study, we aimed to propose a risk stratification and analyze RAI utilization patterns in MSO cases. Methods: The National Cancer Database (NCDB) was queried for patients with MSO between 2004 and 2016. Demographic, oncological, and clinicopathologic data were compared between groups using Fisher's exact test. Kaplan-Meier curves were used to estimate overall survival (OS), and variables associated with OS were assessed via univariate Cox regression. We adapted the 2015 American Thyroid Association risk guidelines for MSO patients. We stratified patients into low-, intermediate-, and high-risk groups using metastasis, extraovarian extension, lymphovascular invasion, lymph node status, surgical margins, tumor size, and grade. Risk stratification, demographic, oncological, and clinicopathologic data were compared between the groups receiving and not receiving RAI therapy. We then queried the Surveillance, Epidemiology, and End Results (SEER) 18 registry for patients with MSO between 2000 and 2018 to confirm our risk stratification analysis. Results: In the NCDB analysis, a total of 158 patients were identified, and 19 received RAI. RAI therapy was associated with distant metastasis (p = 0.005) and lymph node status (p = 0.012). Twenty-one NCDB patients were stratified as high risk, and 30% of high-risk patients received RAI. High-risk stratification was associated with decreased OS via univariate Cox regression (hazard ratio = 4.0 [95% confidence interval 1.11-14.26], p = 0.034). In our subsequent analysis using the SEER registry, there were 95 MSO patients, and 18 received RAI. Again, the majority of high-risk patients did not receive RAI, with only 41% of high-risk patients receiving RAI. Conclusions: MSO is a rare malignancy with apparently variable and inconsistent patterns of postoperative RAI administration. The risk stratification described here provides a framework to identify patients potentially at risk for mortality, and utilization of RAI in this group should be studied further.

Thyroid Abnormalities in Heart Failure.

The effects of hyperthyroidism and hypothyroidism on the heart and cardiovascular system are well documented. It has also been shown that various forms of heart disease including but not limited to congenital, hypertensive, ischemic, cardiac surgery, and heart transplantation cause an alteration in thyroid function tests including a decrease in serum liothyronine (T3). This article discusses the basic science and clinical data that support the hypothesis that these changes pose pathophysiologic and potential novel therapeutic challenges.

Thyroid Abnormalities in Heart Failure.

The effects of hyperthyroidism and hypothyroidism on the heart and cardiovascular system are well documented. It has also been shown that various forms of heart disease including but not limited to congenital, hypertensive, ischemic, cardiac surgery, and heart transplantation cause an alteration in thyroid function tests including a decrease in serum liothyronine (T3). This article discusses the basic science and clinical data that support the hypothesis that these changes pose pathophysiologic and potential novel therapeutic challenges.

Assessment of the Adequacy of Thyroid Hormone Replacement Therapy in Hypothyroidism.

Background: Recent studies identify a significant number of treated hypothyroid patients who express dissatisfaction with their therapy. At present there are sufficient measures of thyroid function to enable the clinician to establish a diagnosis of thyroid disease with a high degree of sensitivity and specificity. The purpose of this study was to quantitate the use of a new and novel assessment of clinically relevant hypothyroid symptoms in the management of patients with thyroid disease and to identify a tool that could help clinicians to assess adequacy of LT4 treatment. Methodology: Unselected outpatients of the Thyroid Clinic of the North Shore University Hospital at Manhasset completed a questionnaire asking them to rate their physical symptoms related to thyroid disease as part of their standard care. This questionnaire consisted of 10 signs and symptoms. The questionnaire was collected from 198 control subjects, 241 subjects with primary hypothyroidism (under treatment), 113 euthyroid subjects (benign nodular thyroid disease), 73 previously hyperthyroid subjects (previously treated), and 27 subjects with thyroid cancer. A repeat questionnaire was obtained from 48 subjects with primary hypothyroidism (20%), 19 euthyroid subjects (17%), and 17 subjects previously hyperthyroid (23%). Data Analysis: The mean score for the sum of the signs and symptoms in the primary hypothyroid group with no medication change was 9.62 ± 1.29 for the initial questionnaire, and 10.04 ± 1.32 for the follow up questionnaire (not significant). For the primary hypothyroid patients requiring a medication change, at the time of the initial questionnaire the mean serum TSH was 12.86 ± 2.75 mcU/ml. Concurrently with the normalization of TSH, a statistically significant improvement in the sum of signs and symptoms mean score for this group was noted (16.32 ± 1.93 initial vs. 10.32 ± 1.46 after treatment to normalize TSH). Conclusion: The proposed newly devised hypothyroid scale correctly identified subjects with TSH elevation and clinical/subclinical hypothyroidism based on their clinical signs and symptoms. In this particular subset of patients, the hypothyroid symptom scale showed a statistically significant improvement in the sum of the signs and symptoms with the normalization of the subjects' thyroid function.

Hypothyroid Symptoms in Levothyroxine-Treated Patients.

PURPOSE: Approximately 15% of patients with hypothyroidism are dissatisfied with their treatment due to persistence of residual symptoms associated with hypothyroidism. The purpose of this study was to compare thyroid symptoms using the hypothyroid symptom scale (HSS) in patients receiving stable thyroid therapy for 6 months to patients without hypothyroidism. The HSS was used to identify the percentage of levothyroxine-treated hypothyroid patients with residual or persistent hypothyroid symptoms. METHODS: Patients included in the study had hypothyroidism and were receiving a stable/maintenance dose of levothyroxine sodium therapy, unchanged for at least 6 months. A control group of patients were included if they did not have an active prescription for thyroid hormone therapy. The HSS was administered via phone or face-to-face interactions. Patients were asked to score 10 symptoms over the past month on a scale of 0 to 4 (e.g., 0, absence of, to 4, severe symptoms). Results were analyzed using descriptive and inferential statistics. T-tests and chi-squared analysis were used to assess differences in continuous and categorical variables. RESULTS: A total of 68% of the contacted patients responded to the survey. A total of 302 patients were in the intervention group and 273 were in the control group. The mean total HSS scores between groups were significantly higher in the treatment compared to the control group (13.92 ± 10.91 vs.10.07 ± 7.85; P < 0.001). CONCLUSION: Significantly more patients receiving thyroid hormone therapy experienced residual thyroid symptoms compared to control patients. Attempts should be made to offer alternatives for hypothyroid patients with persistent symptoms.

Thyroid Hormones and Cardiovascular Function and Diseases.

Thyroid hormone (TH) receptors are present in the myocardium and vascular tissue, and minor alterations in TH concentration can affect cardiovascular (CV) physiology. The potential mechanisms that link CV disease with thyroid dysfunction are endothelial dysfunction, changes in blood pressure, myocardial systolic and diastolic dysfunction, and dyslipidemia. In addition, cardiac disease itself may lead to alterations in TH concentrations (notably, low triiodothyronine syndrome) that are associated with higher morbidity and mortality. Experimental data and small clinical trials have suggested a beneficial role of TH in ameliorating CV disease. The aim of this review is to provide clinicians dealing with CV conditions with an overview of the current knowledge of TH perturbations in CV disease.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS AND AMERICAN COLLEGE OF ENDOCRINOLOGY POSITION STATEMENT ON THYROID DYSFUNCTION CASE FINDING.

Hypothyroidism and hyperthyroidism can be readily diagnosed and can be treated in a safe, cost-effective manner. Professional organizations have given guidance on how and when to employ thyroid-stimulating hormone testing for the detection of thyroid dysfunction. Most recently, the United States Preventive Services Task Force did not endorse screening for thyroid dysfunction based on a lack of proven benefit and potential harm of treating those with thyroid dysfunction, which is mostly subclinical disease. The American Association of Clinical Endocrinologists (AACE) is concerned that this may discourage physicians from testing for thyroid dysfunction when clinically appropriate. Given the lack of specificity of thyroid-associated symptoms, the appropriate diagnosis of thyroid disease requires biochemical confirmation. The Thyroid Scientific Committee of the AACE has produced this White Paper to highlight the important difference between screening and case-based testing in the practice of clinical medicine. We recommend that thyroid dysfunction should be frequently considered as a potential etiology for many of the nonspecific complaints that physicians face daily. The application and success of safe and effective interventions are dependent on an accurate diagnosis. We, therefore, advocate for an aggressive case-finding approach, based on identifying those persons most likely to have thyroid disease that will benefit from its treatment.

Thyroid Disease and the Heart.

Thyroid hormones have an intimate relationship with cardiac function. Some of the most significant clinical signs and symptoms of thyroid disease are the cardiac manifestations. In both hypothyroidism and hyperthyroidism, the characteristic physiological effects of thyroid hormone can be understood from the actions at the molecular and cellular level. Here we explore topics from the metabolism and cellular effects of thyroid hormone to special considerations related to statin and amiodarone therapy for the alterations in thyroid hormone metabolism that accompany heart disease.

Preoperative hypothyroidism is a risk factor for postoperative atrial fibrillation in cardiac surgical patients.

BACKGROUND AND AIM: Although studies analyzing the effect of thyroid supplementation on postoperative morbidity and mortality from cardiac surgery have been inconclusive, they suggest a role in the prevention of postoperative atrial fibrillation. To further explore this relationship we conducted a retrospective study to determine whether abnormalities in routine preoperative thyroid function studies correlate with the incidence of postoperative atrial fibrillation. METHODS: From May 2004 until July 2011, 821 patients with complete thyroid function testing performed preoperatively underwent cardiac surgery. Preoperative, intraoperative, and postoperative laboratory, clinical and hemodynamic data including postoperative electrocardiogram monitoring were retrospectively evaluated. RESULTS: Mean age was 65.7 years and 36% (294) of patients were female. Mean preoperative ejection fraction was 48.6% and 18% (100) had clinical heart failure. Ninety percent (682) of patients were euthyroid and 10% (77) were hypothyroid. Atrial fibrillation occurred significantly more frequently in hypothyroid patients (33.4% vs. 22.5%; p = .033). In multivariable analysis, increasing thyroid stimulating hormone (TSH) level (OR: 1.11; CI: 1.01 to 1.22; p = .030) was an independent predictor of postoperative atrial fibrillation. Beta blocker use within 24 hours prior to operation was protective (OR: .54; CI: .35 to .83; p = .005). Length of stay was significantly longer in patients with postoperative atrial fibrillation (9.1 vs. 6.5 days; p < .001). CONCLUSIONS: In the current study, preoperative hypothyroidism was associated with postoperative atrial fibrillation. Further studies are warranted to delineate whether preoperative hypothyroidism is a useful biomarker for selecting patients most likely to benefit from preoperative thyroid supplementation in the prevention of postoperative atrial fibrillation.

Amiodarone-induced thyroid dysfunction.

Amiodarone is an effective medication for the treatment of cardiac arrhythmias. Originally developed for the treatment of angina, it is now the most frequently prescribed antiarrhythmia drug despite the fact that its use is limited because of potential serious side effects including adverse effects on the thyroid gland and thyroid hormones. Although the mechanisms of action of amiodarone on the thyroid gland and thyroid hormone metabolism are poorly understood, the structural similarity of amiodarone to thyroid hormones, including the presence of iodine moieties on the inner benzene ring, may play a role in causing thyroid dysfunction. Amiodarone-induced thyroid dysfunction includes amiodarone-induced thyrotoxicosis (AIT) and amiodarone-induced hypothyroidism (AIH). The AIT develops more commonly in iodine-deficient areas and AIH in iodine-sufficient areas. The AIT type 1 usually occurs in patients with known or previously undiagnosed thyroid dysfunction or goiter. The AIT type 2 usually occurs in normal thyroid glands and results in destruction of thyroid tissue caused by thyroiditis. This is the result of an intrinsic drug effect from the amiodarone itself. Mixed types are not uncommon. Patients with cardiac disease receiving amiodarone treatment should be monitored for signs of thyroid dysfunction, which often manifest as a reappearance of the underlying cardiac disease state. When monitoring patients, initial tests should include the full battery of thyroid function tests, thyroid-stimulating hormone, thyroxine, triiodothyronine, and antithyroid antibodies. Mixed types of AIT can be challenging both to diagnose and treat and therapy differs depending on the type of AIT. Treatment can include thionamides and/or glucocorticoids. The AIH responds favorably to thyroid hormone replacement therapy. Amiodarone is lipophilic and has a long half-life in the body. Therefore, stopping the amiodarone therapy usually has little short-term benefit.

Reductions in serum levels of LDL cholesterol, apolipoprotein B, triglycerides and lipoprotein(a) in hypercholesterolaemic patients treated with the liver-selective thyroid hormone receptor agonist eprotirome.

BACKGROUND: Liver-selective thyromimetic agents could provide a new approach for treating dyslipidaemia. METHODS: We performed a multicentre, randomized, placebo-controlled, double-blind study to evaluate the efficacy and safety of eprotirome, a liver-selective thyroid hormone receptor agonist, in 98 patients with primary hypercholesterolaemia. After previous drug wash-out and dietary run-in, patients received 100 or 200 µg day(-1) eprotirome or placebo for 12 weeks. The primary end-point was change in serum LDL cholesterol; secondary end-points included changes in other lipid parameters and safety measures. RESULTS: Eprotirome treatment at 100 and 200 µg daily reduced serum LDL cholesterol levels by 23 ± 5% and 31 ± 4%, respectively, compared with 2 ± 6% for placebo (P < 0.0001). Similar reductions were seen in non-HDL cholesterol and apolipoprotein (apo) B, whereas serum levels of HDL cholesterol and apo A-I were unchanged. There were also considerable reductions in serum triglycerides and lipoprotein(a), in particular in patients with elevated levels at baseline. There was no evidence of adverse effects on heart or bone and no changes in serum thyrotropin or triiodothyronine, although the thyroxine level decreased. Low-grade increases in liver enzymes were evident in most patients. CONCLUSION: In hypercholesterolaemic patients, the liver-selective thyromimetic eprotirome decreased serum levels of atherogenic lipoproteins without signs of extra-hepatic side effects. Selective stimulation of hepatic thyroid hormone receptors may be an attractive way to modulate lipid metabolism in hyperlipidaemia.

Thyroid disease and the cardiovascular system.

Thyroid hormones, specifically triiodothyronine (T3), have significant effects on the heart and cardiovascular system. Hypothyroidism, hyperthyroidism, subclinical thyroid disease, and low T3 syndrome each cause cardiac and cardiovascular abnormalities through both genomic and nongenomic effects on cardiac myocytes and vascular smooth muscle cells. In compromised health, such as occurs in heart disease, alterations in thyroid hormone metabolism may further impair cardiac and cardiovascular function. Diagnosis and treatment of cardiac disease may benefit from including analysis of thyroid hormone status, including serum total T3 levels.

Discovery of 2-[3,5-dichloro-4-(5-isopropyl-6-oxo-1,6-dihydropyridazin-3-yloxy)phenyl]-3,5-dioxo-2,3,4,5-tetrahydro[1,2,4]triazine-6-carbonitrile (MGL-3196), a Highly Selective Thyroid Hormone Receptor ß agonist in clinical trials for the treatment of dyslipidemia.

The beneficial effects of thyroid hormone (TH) on lipid levels are primarily due to its action at the thyroid hormone receptor ß (THR-ß) in the liver, while adverse effects, including cardiac effects, are mediated by thyroid hormone receptor α (THR-α). A pyridazinone series has been identified that is significantly more THR-ß selective than earlier analogues. Optimization of this series by the addition of a cyanoazauracil substituent improved both the potency and selectivity and led to MGL-3196 (53), which is 28-fold selective for THR-ß over THR-α in a functional assay. Compound 53 showed outstanding safety in a rat heart model and was efficacious in a preclinical model at doses that showed no impact on the central thyroid axis. In reported studies in healthy volunteers, 53 exhibited an excellent safety profile and decreased LDL cholesterol (LDL-C) and triglycerides (TG) at once daily oral doses of 50 mg or higher given for 2 weeks.

Clinical practice guidelines for hypothyroidism in adults: cosponsored by the American Association of Clinical Endocrinologists and the American Thyroid Association.

OBJECTIVE: Hypothyroidism has multiple etiologies and manifestations. Appropriate treatment requires an accurate diagnosis and is influenced by coexisting medical conditions. This paper describes evidence-based clinical guidelines for the clinical management of hypothyroidism in ambulatory patients. METHODS: The development of these guidelines was commissioned by the American Association of Clinical Endocrinologists (AACE) in association with American Thyroid Association (ATA). AACE and the ATA assembled a task force of expert clinicians who authored this article. The authors examined relevant literature and took an evidence-based medicine approach that incorporated their knowledge and experience to develop a series of specific recommendations and the rationale for these recommendations. The strength of the recommendations and the quality of evidence supporting each was rated according to the approach outlined in the American Association of Clinical Endocrinologists Protocol for Standardized Production of Clinical Guidelines-2010 update. RESULTS: Topics addressed include the etiology, epidemiology, clinical and laboratory evaluation, management, and consequences of hypothyroidism. Screening, treatment of subclinical hypothyroidism, pregnancy, and areas for future research are also covered. CONCLUSIONS: Fifty-two evidence-based recommendations and subrecommendations were developed to aid in the care of patients with hypothyroidism and to share what the authors believe is current, rational, and optimal medical practice for the diagnosis and care of hypothyroidism. A serum thyrotropin is the single best screening test for primary thyroid dysfunction for the vast majority of outpatient clinical situations. The standard treatment is replacement with L-thyroxine. The decision to treat subclinical hypothyroidism when the serum thyrotropin is less than 10 mIU/L should be tailored to the individual patient.

Clinical practice guidelines for hypothyroidism in adults: cosponsored by the American Association of Clinical Endocrinologists and the American Thyroid Association.

BACKGROUND: Hypothyroidism has multiple etiologies and manifestations. Appropriate treatment requires an accurate diagnosis and is influenced by coexisting medical conditions. This paper describes evidence-based clinical guidelines for the clinical management of hypothyroidism in ambulatory patients. METHODS: The development of these guidelines was commissioned by the American Association of Clinical Endocrinologists (AACE) in association with American Thyroid Association (ATA). AACE and the ATA assembled a task force of expert clinicians who authored this article. The authors examined relevant literature and took an evidence-based medicine approach that incorporated their knowledge and experience to develop a series of specific recommendations and the rationale for these recommendations. The strength of the recommendations and the quality of evidence supporting each was rated according to the approach outlined in the American Association of Clinical Endocrinologists Protocol for Standardized Production of Clinical Guidelines-2010 update. RESULTS: Topics addressed include the etiology, epidemiology, clinical and laboratory evaluation, management, and consequences of hypothyroidism. Screening, treatment of subclinical hypothyroidism, pregnancy, and areas for future research are also covered. CONCLUSIONS: Fifty-two evidence-based recommendations and subrecommendations were developed to aid in the care of patients with hypothyroidism and to share what the authors believe is current, rational, and optimal medical practice for the diagnosis and care of hypothyroidism. A serum thyrotropin is the single best screening test for primary thyroid dysfunction for the vast majority of outpatient clinical situations. The standard treatment is replacement with L-thyroxine. The decision to treat subclinical hypothyroidism when the serum thyrotropin is less than 10 mIU/L should be tailored to the individual patient.

Association of serum triiodothyronine with B-type natriuretic peptide and severe left ventricular diastolic dysfunction in heart failure with preserved ejection fraction.

There are well-documented changes in thyroid hormone metabolism that accompany heart failure (HF). However, the frequency of thyroid hormone abnormalities in HF with preserved ejection fraction (HFpEF) is unknown, and no studies have investigated the association between triiodothyronine (T(3)) and markers of HF severity (B-type natriuretic peptide [BNP] and diastolic dysfunction [DD]) in HFpEF. In this study, 89 consecutive patients with HFpEF, defined as symptomatic HF with a left ventricular ejection fraction >50% and a left ventricular end-diastolic volume index <97 ml/m(2), were prospectively studied. Patients were dichotomized into 2 groups on the basis of median T(3) levels, and clinical, laboratory, and echocardiographic data were compared between groups. Univariate and multivariate linear regression analyses were performed to determine whether BNP and DD were independently associated with T(3) level. We found that 22% of patients with HFpEF had reduced T(3). Patients with lower T(3) levels were older, were more symptomatic, more frequently had hyperlipidemia and diabetes, and had higher BNP levels. Severe (grade 3) DD, higher mitral E velocity, shorter deceleration time, and higher pulse pressure/stroke volume ratio were all associated with lower T(3) levels. T(3) was inversely associated with log BNP (p = 0.004) and the severity of DD (p = 0.039). On multivariate analysis, T(3) was independently associated with log BNP (ß = -4.7 ng/dl, 95% confidence interval -9.0 to -0.41 ng/dl, p = 0.032) and severe DD (ß = -16.3 ng/dl, 95% confidence interval -30.1 to -2.5 ng/dl, p = 0.022). In conclusion, T(3) is inversely associated with markers of HFpEF severity (BNP and DD). Whether reduced T(3) contributes to or is a consequence of increased severity of HFpEF remains to be determined.