Current trends in the management of Graves' disease

Radioactive Iodine Therapy of Graves' Disease in Patients Pretreated With Methimazole Without Radioiodine Uptake for Dose Estimation

OBJECTIVE

To assess response predictors to radioactive iodine (RAI) therapy without using thyroid uptake for dose estimate in patients pretreated with methimazole.

METHODS

Retrospective analysis was performed of patients with Graves' disease treated with RAI doses determined without using uptake studies.

RESULTS

In 242 patients (median age, 41.9 years; 66.1% female), initial mean free thyroxine (FT4) level was 4.7 ng/dL with an estimated thyroid size of 49.15 g. Prior to RAI therapy, average methimazole dose was 22.7 mg/day. Mean RAI dose was 737.0 ±199.4 MBq (19.9 ± 5.4 mCi). Two hundred eight patients (85.9%) responded to RAI therapy; 185 (88.9%) became hypothyroid and 23 (11.1%) became euthyroid. The majority (90.4%) responded within 6 months of therapy with a quicker response (13.9 ± 8.3 vs 17.5 ± 13.5 weeks) for those treated with doses per gram of ≥14.8 MBq (0.4 mCi). Thirty-four nonresponders had a higher initial FT4 level and larger thyroid size with a lower RAI dose per gram of thyroid tissue. In multivariate analysis, the independent response predictor to therapy was dose per gram of thyroid tissue of ≥14.8 MBq (0.4 mCi) (hazard ratio, 3.18; 95% CI, 1.1-9.7). Doses per gram of 14.8 to 18.1 MBq (0.4-0.5 mCi) achieved maximal response rate without added advantage of higher doses. Thyroid size prior to RAI therapy, FT4 levels at diagnosis, and age were inversely related to response.

CONCLUSION

RAI therapy for Graves' disease without uptake studies for dose estimates is an effective treatment method. In patients pretreated with methimazole, an RAI dose per gram of thyroid tissue of ≥14.8 MBq (0.4 mCi) showed high response rate. Prospective studies are needed to confirm the viability of this simplified and cost-effective approach.

Radioactive Iodine: A Living History

Background: Before the development of antithyroid drugs in the 1940s, treatment of Graves' hyperthyroidism was primarily surgical. Surgical mortality was quite variable, but a significant minority of patients died during or after surgery. Summary: In 1936, Karl Compton, President of the Massachusetts Institute of Technology, in a lecture attended by Massachusetts General Hospital physicians, suggested that artificially radioactive isotopes might be useful for studying metabolism. By 1942, Hertz and Roberts reported on the successful use of radioactive iodine (RAI) to treat Graves' hyperthyroidism. RAI uptake was subsequently demonstrated in well-differentiated thyroid cancer metastases. In 1948, Seidlin demonstrated stimulation of uptake in thyroid cancer metastases by thyrotropin (TSH). By 1990, 69% of endocrinologists in North America recommended RAI for Graves' hyperthyroidism. Currently RAI is less frequently used for Graves' hyperthyroidism, related to concerns about exacerbation of thyroid eye disease, about radiation exposure, and about potential adverse consequences of permanent hypothyroidism. Similarly, RAI was administered to the majority of patients with thyroid cancer for decades, but its use is now more selective. Conclusions: RAI is a remarkable example of interinstitutional cooperation between physicians and scientists to transition from bench to bedside in only three years. It is the model for a theranostic approach to disease (the simultaneous use of a radioactive drug for diagnosis and therapy). The future of RAI is less certain; inhibition of TSH receptor stimulating antibodies in Graves' disease and more precise targeting of genes that drive thyroid oncogenesis may diminish the use of RAI. Alternatively, redifferentiation techniques may improve the efficacy of RAI in RAI-refractory thyroid cancer.

Long-term thionamide antithyroid treatment of Graves' disease

Thionamide antithyroid drugs (ATD) are the treatment of choice for Graves' hyperthyroidism. The major drawback of ATD treatment for 1-2 years is the relapse of hyperthyroidism in about 50% of patients. Recently, it has been shown that ATD treatment for more than five years is accompanied by long-term remission in majority of patients without additional major side effects in both adults and children. Compared to radioactive iodine therapy, long-term ATD results in more favorable outcomes. This review summarizes the evidence on long-term ATD therapy regarding the remission rate of hyperthyroidism, efficacy and safety, indications and mode of therapy in patients with hyperthyroidism.

Postradioiodine Graves' management: The PRAGMA study

OBJECTIVE

Thyroid status in the months following radioiodine (RI) treatment for Graves' disease can be unstable. Our objective was to quantify frequency of abnormal thyroid function post-RI and compare effectiveness of common management strategies.

DESIGN

Retrospective, multicentre and observational study.

PATIENTS

Adult patients with Graves' disease treated with RI with 12 months' follow-up.

MEASUREMENTS

Euthyroidism was defined as both serum thyrotropin (thyroid-stimulating hormone [TSH]) and free thyroxine (FT4) within their reference ranges or, when only one was available, it was within its reference range; hypothyroidism as TSH ≥ 10 mU/L, or subnormal FT4 regardless of TSH; hyperthyroidism as TSH below and FT4 above their reference ranges; dysthyroidism as the sum of hypo- and hyperthyroidism; subclinical hypothyroidism as normal FT4 and TSH between the upper limit of normal and <10 mU/L; and subclinical hyperthyroidism as low TSH and normal FT4.

RESULTS

Of 812 patients studied post-RI, hypothyroidism occurred in 80.7% and hyperthyroidism in 48.6% of patients. Three principal post-RI management strategies were employed: (a) antithyroid drugs alone, (b) levothyroxine alone, and (c) combination of the two. Differences among these were small. Adherence to national guidelines regarding monitoring thyroid function in the first 6 months was low (21.4%-28.7%). No negative outcomes (new-onset/exacerbation of Graves' orbitopathy, weight gain, and cardiovascular events) were associated with dysthyroidism. There were significant differences in demographics, clinical practice, and thyroid status postradioiodine between centres.

CONCLUSIONS

Dysthyroidism in the 12 months post-RI was common. Differences between post-RI strategies were small, suggesting these interventions alone are unlikely to address the high frequency of dysthyroidism.

Empiric radioiodine for hyperthyroidism: Outcomes, prescribing patterns, and its place in the modern era of theranostics

BACKGROUND

The modern era of radioiodine (I-131) theranostics for metastatic differentiated thyroid cancer requires us to rationalize the role of traditional empiric prescription in nonmalignant thyroid disease. We currently practice empiric I-131 prescription for treatment of hyperthyroidism. This study aims to assess outcomes after treatment of hyperthyroidism by empiric I-131 prescription at our centre, evaluate factors that impact on outcomes and prescribing practice, and gain insight into whether there is a place for theranostically-guided prescription in hyperthyroidism.

PATIENTS AND METHODS

A retrospective review was undertaken of all patients with Graves' disease, toxic multinodular goitre (MNG) and toxic adenoma treated with I-131 between 2016 and 2021. Associations between clinical or scintigraphic variables and remission (euthyroid or hypothyroid) or persistence of hyperthyroidism at follow-up were performed using standard t test as well as Pearson's product correlation.

RESULTS

Of 146 patients with a mean follow-up of 13.6 months, 80.8% achieved remission of hyperthyroidism. This was highest in toxic nodules (90.1%), compared with Graves' disease (73.8%) and toxic MNG (75.5%). In patients with Graves' disease, higher administered activity was associated with remission (p = .035). There was a weak inverse correlation between the Tc-99m pertechnetate uptake vs prescribed activity in Graves' disease (r = -0.33; p = .009). Only one patient (0.7%) had an I-131 induced flare of thyrotoxicosis.

CONCLUSION

Traditional empiric I-131 prescription is a safe and effective treatment of hyperthyroidism and suitable for most patients. However, there may be a role for personalized I-131 prescription by theranostic guidance in selected patients with high thyroid hyperactivity.

Appropriate duration of antithyroid drug treatment as a predictor for relapse of Graves' disease: a systematic scoping review

BACKGROUND

Following the conventional 12-18 month antithyroid drug (ATD) treatment in Graves' disease (GD), 50% of patients experience relapse of hyperthyroidism.

OBJECTIVE

The aim of this systematic scoping review was critical appraisal of duration of ATD therapy in the last 80 years.

METHODS

Articles were identified through the search of PubMed from January 1, 1941 to April 30, 2021. All study types were included. Articles were eligible if they reported data on the length of ATD treatment, particularly thyroid hormones and TSH receptor antibodies (TRAb) concentrations and specifically those with data on the remission and/or relapse rates.

RESULTS

We described major progress regarding the duration of ATD therapy and related outcomes at every 20 years. Articles of 1941-1960 were mainly concerned with determination of favorable treatment, minimal effective dose, side effects and rate of remission after < 12-month ATD therapy. Studies with larger number of patients and longer follow-ups appeared in 1961-1980; higher remission rate after 18-24 months versus 6 months of ATD therapy was reported. Articles of 1981-2000 focused on identification of factors associated with high relapse rates after discontinuation of ATD. In 2001-2021, ATD became the first choice of treatment in many countries. However, 12-18 months of ATD therapy was arbitrarily chosen as the appropriate option. According to recent studies, persistent normalization of TRAb occurs after 5 years of methimazole therapy and ATD treatment of > 60 months could offer a 4-year remission rate of 85%.

CONCLUSION

Long-term ATD treatment for more than 60 months is safe and effective, has the highest remission rate and cures most patients with GD; hence, it should be considered as the most appropriate duration for ATD therapy in these patients.

Long-term antithyroid drug therapy

PURPOSE OF REVIEW

Over the last 1-2 decades, patients and physicians have preferred antithyroid drug therapy as the initial treatment of Graves' disease, rather than radioactive iodine or surgery. More recently, the concept of long-term antithyroid drug therapy (LTADT; >24 months of treatment) has also become increasingly popular.

RECENT FINDINGS

Data from cohort studies and a prospective randomized trial suggest that LTATD therapy is safe and is associated with a higher chance of remission from Graves' disease than is shorter-term therapy. Also, LTADT may be associated with better quality of life and other clinical outcomes compared to radioiodine and surgery.

SUMMARY

Long-term antithyroid drug therapy is appropriate for children and young adults. This approach is a reasonable option in those who are doing well on a stable low dose of antithyroid drug therapy, and especially those who wish to avoid definitive treatment with radioactive iodine or surgery, given their inherent risks and need for lifelong hormonal replacement therapy.

Treatment of patients with Graves' disease in Sweden compared to international surveys of an 'index patient'

Introduction

The treatment strategies for a 42‐year‐old female index patient with moderate Graves’ disease (GD) vary according to several international surveys. The important question whether surveys of treatment preferences in theoretical patient cases also match how real patients are treated has not yet been addressed.

Materials and Methods

From a Swedish cohort of 1186 GD patients (TT‐12 cohort), 27 women were identified using the same criteria as from the index patient surveys from the European and American Thyroid Associations. This ‘index patient cohort’ was age 40–45, otherwise healthy female, with two children and uncomplicated GD. The applied first‐line treatment of the patients in the index cohort, together with its variations, was compared with the treatment preferences according to international surveys. A comparison with the TT‐12 cohort was also performed.

Results

In the ‘Index cohort’, 77.8% were treated with antithyroid drugs (ATD), and 22.2% were treated with radioiodine (¹³¹I). This preference for ATD is in line with most countries/regions, with the exception of USA and the Middle East/North Africa, where ¹³¹I was preferred. The distribution of treatment in the TT‐12 cohort did not significantly differ from the index cohort. ATD was the preferred treatment in male and young (age 19–22) patients, as was RAI in old (age 69–73) patients. The age‐related, but not the gender‐related, cases differed significantly from the entire TT‐12 cohort.

Conclusion

The treatment choice in an index patient in Sweden seems in line with European practice, where ATD is the preferred first choice. This differs compared to US and North African survey intentions, where ¹³¹I is more often used. Age more than gender influences the treatment choice of GD patients. This is, to our best knowledge, the first time an index patient from ‘real life’ has been presented and compared to treatment preferences of international thyroid association surveys.

Total thyroidectomy: Safe and curative treatment option for hyperthyroidism

BACKGROUND

While use of total thyroidectomy has increased in management of hyperthyroidism, concerns exist about increased surgical complication rates; most notably, hematoma, recurrent laryngeal nerve (RLN) injury, and hypocalcemia.

METHODS

Retrospective cohort study of 454 patients undergoing total thyroidectomy between 2003 and 2015. All patients had surgery for hyperthyroidism, benign euthyroid disease, or thyroid malignancy.

RESULTS

Total thyroidectomy for hyperthyroidism was not associated with an increased risk for any postoperative complication. Transient hypocalcemia, temporary dysphonia, and postoperative hematoma rates were not significantly different for patients with hyperthyroid (n = 91), euthyroid benign (n = 237), and malignant (n = 126) disease. Permanent hypocalcemia and recurrent laryngeal nerve injury were not noted in any hyperthyroid patients. Complication rates were similar for hyperthyroid patients with Graves' disease vs toxic multinodular goiter.

CONCLUSION

This study affirms safety and efficacy of total thyroidectomy as standard treatment for hyperthyroidism.

The Role of Surgery in Autoimmune Conditions of the Thyroid

The two most common autoimmune conditions of the thyroid include chronic lymphocytic (Hashimoto's) thyroiditis and Graves' disease. Both conditions can be treated medically, but surgery plays an important role. Hashimoto's thyroiditis and Graves' disease are mediated by autoantibodies that interact directly with the thyroid, creating inflammation and impacting thyroid function. Patients may develop large goiters with compressive symptoms or malignancy requiring surgical intervention. In addition, there are several surgical indications specific to Hashimoto's and Graves' Disease.

MANAGEMENT OF THYROTOXICOSIS AMONG GENERAL PRACTITIONERS IN TRINIDAD COMPARED WITH 2016 AMERICAN THYROID ASSOCIATION GUIDELINES FOR HYPERTHYROIDISM

Objective: A previous Trinidadian survey highlighted the investigative and therapeutic approaches selected by general practitioners (GPs) in managing thyrotoxicosis. The main objective of this study was to compare practice with existing guidelines. Methods: In this cross-sectional study a pretested de novo questionnaire was self-administered to GPs throughout Trinidad. The survey evaluated GPs' choices in management of thyrotoxicosis cases and compared their responses to the 2016 American Thyroid Association guidelines as well as with those previously reported locally. Results: A total of 159 completed questionnaires were analyzed (59% response rate). Thyroid stimulating hormone was the preferred (94%) biochemical test to confirm thyrotoxicosis etiology. A combination of ultra-sound and thyroid scintigraphy, thyroid ultrasound alone, and scintigraphy only were the testing options selected by 41%, 38%, and 12%, respectively. Generally medical therapy with antithyroid drugs was the preferred treatment option with 86% of respondents selecting this option for the index case of newly diagnosed female Graves disease. The greatest proportion of respondents that selected radioactive iodine (RAI) was 35% for both the index case as well as the male equivalent. Surgery was the most popular option at 25% for patients with a toxic multinodular goiter. Having access to RAI and scintigraphy was reported by 32% and 28%, respectively. Conclusion: GPs appear to be constrained to making rational choices based upon availability rather than what the guidelines recommend. In the absence of formal continuing medical education for GPs on thyrotoxicosis, dissemination of guidelines at the primary care level may reduce this gap. Abbreviations: ATA = American Thyroid Association; ATD = antithyroid drugs; CME = continued medical education; GP = general practitioner; RAI = radioactive iodine; SURG = surgery; T4 = thyroxine; TSH = thyroid-stimulating hormone.

Amiodarone and thyroid physiology, pathophysiology, diagnosis and management

Although amiodarone is considered the most effective antiarrhythmic agent, its use is limited by a wide variety of potential toxicities. The purpose of this review is to provide a comprehensive "bench to bedside" overview of the ways amiodarone influences thyroid function. We performed a systematic search of MEDLINE to identify peer-reviewed clinical trials, randomized controlled trials, meta-analyses, and other clinically relevant studies. The search was limited to English-language reports published between 1950 and 2017. Amiodarone was searched using the terms adverse effects, hypothyroidism, myxedema, hyperthyroidism, thyroid storm, atrial fibrillation, ventricular arrhythmia, and electrical storm. Google and Google scholar as well as bibliographies of identified articles were reviewed for additional references. We included 163 germane references in this review. Because amiodarone is one of the most frequently prescribed antiarrhythmic drugs in the United States, the mechanistic, diagnostic and therapeutic information provided is relevant for practicing clinicians in a wide range of medical specialties.

Comparative Effectiveness of Treatment Choices for Graves' Hyperthyroidism: A Historical Cohort Study

BACKGROUND

The optimum therapy for Graves' disease (GD) is chosen following discussion between physician and patient regarding benefits, drawbacks, potential side effects, and logistics of the various treatment options, and it takes into account patient values and preferences. This cohort study aimed to provide useful information for this discussion regarding the usage, efficacy, and adverse-effect profile of radioactive iodine (RAI), antithyroid drugs (ATDs), and thyroidectomy in a tertiary healthcare facility.

METHODS

The cohort included consecutive adults diagnosed with GD from January 2002 to December 2008, who had complete follow-up after treatment at the Mayo Clinic, Rochester, Minnesota. Data on treatment modalities, disease relapses, and adverse effects were extracted manually and electronically from the electronic medical records. Kaplan-Meier analyses were performed to evaluate the association of treatments with relapse-free survival.

RESULTS

The cohort included 720 patients with a mean age of 49.3 years followed for a mean of 3.3 years. Of these, 76.7% were women and 17.1% were smokers. The initial therapy was RAI in 75.4%, ATDs in 16.4%, and thyroidectomy in 2.6%, while 5.6% opted for observation. For the duration of follow-up, ATDs had an overall failure rate of 48.3% compared with 8% for RAI (hazard ratio = 7.6; p < 0.0001). Surgery had a 100% success rate; 80% of observed patients ultimately required therapy. Adverse effects developed in 43 (17.3%) patients treated with ATDs, most commonly dysgeusia (4.4%), rash (2.8%), nausea/gastric distress (2.4%), pruritus (1.6%), and urticaria (1.2%). Eight patients treated with RAI experienced radiation thyroiditis (1.2%). Thyroidectomy resulted in one (2.9%) hematoma and one (2.85%) superior laryngeal nerve damage, with no permanent hypocalcemia.

CONCLUSIONS

RAI was the most commonly used modality within the cohort and demonstrated the best efficacy and safety profile. Surgery was also very effective and relatively safe in the hands of experienced surgeons. While ATDs allow preservation of thyroid function, a high relapse rate combined with a significant adverse-effect profile was documented. These data can inform discussion between physician and patient regarding choice of therapy for GD.

Management of hyperthyroidism due to Graves' disease: frequently asked questions and answers (if any)

Graves' disease is the most common cause of hyperthyroidism in iodine-replete areas. Although progress has been made in our understanding of the pathogenesis of the disease, no treatment targeting pathogenic mechanisms of the disease is presently available. Therapies for Graves' hyperthyroidism are largely imperfect because they are bound to either a high rate of relapsing hyperthyroidism (antithyroid drugs) or lifelong hypothyroidism (radioiodine treatment or thyroidectomy). Aim of the present article is to offer a practical guidance to the reader by providing evidence-based answers to frequently asked questions in clinical practice.

Long-Term Results of Fixed High-Dose I-131 Treatment for Toxic Nodular Goiter: Higher Euthyroidism Rates in Geriatric Patients

Objective:

Geriatric patient population has special importance due to particular challenges. In addition to the increase in incidence of toxic nodular goiter (TNG) with age, it has a high incidence in the regions of low-medium iodine intake such as in our country. The aim of this study was to evaluate the overall outcome of high fixed dose radioiodine (RAI) therapy, and investigate the particular differences in the geriatric patient population.

Methods:

One hundred and three TNG patients treated with high dose I-131 (370-740 MBq) were retrospectively reviewed. The baseline characteristics; age, gender, scintigraphic patterns and thyroid function tests before and after treatment, as well as follow-up, duration of antithyroid drug (ATD) medication and achievement of euthyroid or hypothyroid state were evaluated. The patient population was divided into two groups as those=>65 years and those who were younger, in order to assess the effect of age.

Results:

Treatment success was 90% with single dose RAI therapy. Hyperthyroidism was treated in 7±7, 2 months after RAI administration. At the end of the first year, overall hypothyroidism rate was 30% and euthyroid state was achieved in 70% of patients. Age was found to be the only statistically significant variable effecting outcome. A higher ratio of euthyroidism was achieved in the geriatric patient population.

Conclusion:

High fixed dose I-131 treatment should be preferred in geriatric TNG patients in order to treat persistent hyperthyroidism rapidly. The result of this study suggests that high fixed dose RAI therapy is a successful modality in treating TNG, and high rates of euthyroidism can be achieved in geriatric patients.

Radioiodine therapy versus antithyroid drugs in Graves' disease: a meta-analysis of randomized controlled trials

OBJECTIVE:

This meta-analysis was performed to compare radioiodine therapy with antithyroid drugs in terms of clinical outcomes, including development or worsening of ophthalmopathy, hyperthyroid cure rate, hypothyroidism, relapse rate and adverse events.

METHODS:

Randomized controlled trials (RCTs) published in PubMed, Embase, Web of Science, SinoMed and National Knowledge Infrastructure, China, were systematically reviewed to compare the effects of radioiodine therapy with antithyroid drugs in patients with Graves' disease. Results were expressed as risk ratio with 95% confidence intervals (CIs) and weighted mean differences with 95% CIs. Pooled estimates were performed using a fixed-effects model or random-effects model, depending on the heterogeneity among studies.

RESULTS:

17 RCTs involving 4024 patients met the inclusion criteria and were included. Results showed that radioiodine treatment has increased risk in new ophthalmopathy, development or worsening of ophthalmopathy and hypothyroidism. Whereas, compared with antithyroid drugs, radioiodine treatment seems to have a higher hyperthyroid cure rate, lower recurrence rate and lower incidence of adverse events.

CONCLUSION:

Radioiodine therapy is associated with a higher hyperthyroid cure rate and lower relapse rate compared with antithyroid drugs. However, it also increases the risk of ophthalmopathy and hypothyroidism.

ADVANCES IN KNOWLEDGE:

Considering that antithyroid drug treatment can be associated with unsatisfactory control of hyperthyroidism, we would recommend radioiodine therapy as the treatment of choice for patients with Graves' disease.

The preliminary clinical observation and analysis of childbearingage women with a history of iodine-131 treatment for Graves' disease

Whether radioactive iodine treatment of Graves' disease (GD) during pregnancy will increase pregnancy loss and affect fetal development is still a matter of concern. From May 2005 to December 2015, 2,276 childbearing-age women with GD received iodine-131 treatment in our departments and were retrospectively enrolled in our study. When some of them were found to have been pregnant, their thyroid functions were measured every 4 weeks, in addition, thyroid-stimulating hormone (TSH) was measured 6 weeks after delivery. When necessary, levothyroxine or propylthiouracil (PTU) was given in order to control their TSH levels during pregnancy. Finally, 69 pregnant women (29 ± 3.5 years old) and 1346 women who were not pregnant during the follow-up period were enrolled into this study. They were all hyperthyroid before or during pregnancy. Among 69 pregnant women, the administrated amount of iodine-131 was 254.9 ± 99.9 MBq. Fifty patients became subclinically hypothyroid after treatment and were administrated levothyroxine (55 ± 25 μg/d). Seven patients were diagnosed with subclinical hyperthyroidism during pregnancy and they received PTU (25 ± 12.5 mg/d). Twelve patients with normal thyroid function were also clinically followed. Among 69 women, 63 had a single birth, 3 had dizygotic twins, 2 had two pregnancies and 1 had a single twin birth. Sixty five babies were born full-term, while 9 were premature (4 ± 1 weeks early) with birth weight 3.2 ± 0.5 kg. Six new born babies were considered to be low birth weight infants (< 2.5 kg) while 5 were high birth weight (> 4 kg), but the weights of all the infants were within the normal range. During the period of observation to December 2015, all the infants were found to grow and develop normally. Among 1346 women who were not pregnant were in the further follow-up. Our study found no detrimental effects of the iodine-131 treatment in the pregnant women or their offspring so far.

The effect of prior antithyroid drug use on delaying remission in high uptake Graves' disease following radioiodine ablation

Antithyroid drugs (ATDs) have been shown to attenuate the effectiveness of radioiodine (radioiodine ablation, RIA) therapy in Graves' disease. We undertook a study to look at the impact of iodine uptakes on the outcome of (131)I therapy. To determine the effect of prior ATD use on the duration of time to achieve cure in patients with high vs intermediate uptake Graves' disease who received a fixed dose (15 mCi) of (131)I radioiodine. In a retrospective study of patients with Graves' disease, 475 patients who underwent RIA were followed-up on a two-monthly basis with thyroid function tests. Of the 123 patients with a documented preablation RAIU and consistent follow-up it was observed that 40 patients had an intermediate RAIU (10-30%) and 83 subjects had a distinctly increased uptake (>30%). Successful cure was defined as the elimination of thyrotoxicosis in the form of low free thyroxin and rising TSH levels. When a standard dose of 15 mCi (131)I was administered, a cure rate of 93% was achieved. The median duration of time to cure (TC) was 129 days. Surprisingly, a direct proportional linear relationship (R(2)=0.92) was established between time to cure and radioiodine uptake (TC> 3 0%=172days, TC10 - 3 0%=105 days, P<0.001). Patients who used ATD medications took a proportionately longer duration to achieve remission (TCNO ATD=102days, TCATD=253days, P<0.001). The effect of prior ATD therapy in delaying remission was amplified in the subset of patients with higher uptakes (TC> 3 0% + ATD=310days, TC> 3 0% + NO ATD=102days, P<0.001) compared to those with the intermediate uptakes (TC10 - 3 0% + ATD=126 days, TC10 - 3 0% + NO ATD=99 days, P<0.001). RIA, using a dose of 15 mCi achieved a high cure rate. Higher uptakes predicted longer time to achieve remission, with prior ATD use amplifying this effect.

A 2013 European survey of clinical practice patterns in the management of Graves' disease

OBJECTIVE

Management of Graves' disease (GD) in Europe was published in 1987. Aim of this survey was to provide an update on clinical practice in Europe, and to compare it with a 2011 American survey.

DESIGN

Members of the European Thyroid Association (ETA) were asked to participate in a survey on management of GD, using the same questionnaire of a recent American survey.

RESULTS

A total of 147 ETA members participated. In addition to serum TSH and free T4 assays, most respondents would request TSH-receptor autoantibody (TRAb) measurement (85·6%) and thyroid ultrasound (70·6%) to confirm aetiology, while isotopic studies were selected by 37·7%. Antithyroid drug (ATD) therapy was the preferred first-line treatment (83·8%). Compared to the previous European survey, Europeans currently more frequently use TRAb measurement and thyroid ultrasound for diagnosis and evaluation, but first-line treatment remains ATDs in a similar percentage of respondents. Current clinical practice patterns differ from those in North America, where isotopic studies are more frequently used, and radioiodine (RAI) still is first-line treatment. When RAI treatment is selected in the presence of mild Graves' orbitopathy and/or associated risk factors for its occurrence/exacerbation, steroid prophylaxis is frequently used. The preferred ATD in pregnancy is propylthiouracil in the first trimester and methimazole in the second and third trimesters, similar to North America.

CONCLUSIONS

Significant changes in clinical practice patterns in Europe were noted compared to the previous European survey, as well as persisting differences in diagnosis and therapy between Europe and North America.

Quantitative mRNA expression analysis of selected genes in patients with early-stage hypothyroidism induced by treatment with iodine-131

The present study aimed to investigate the molecular markers indicative of early-stage hypothyroidism induced by treatment with iodine-131, in order to assist in further investigations of radio iodine‑induced hypothyroidism. A total of 59 patients diagnosed with hyperthyroidism (male/female, 16/43; median age, 46.4 years) and 27 healthy subjects (male/female, 7/21; median age, 44.6 years) were included in the present study. All patients were treated with appropriate doses of iodine‑131 and, three months following treatment, the patients were subdivided into two groups: A group with early‑stage hypothyroidism symptoms, and a group with non‑early‑stage hypothyroidism, including euthyroid patients and patients remaining with hyperthyroidism. Tissue samples from the patients and healthy subjects were collected by fine needle biopsies, and the mRNA expression levels of B-cell lymphoma 2 (Bcl‑2), nuclear factor (NF)‑κB, Ku70, epidermal growth factor receptor (EGFR), early growth response 1 (Egr‑1), TP53 and ataxia telangiectasia mutated were analyzed using reverse transcription‑quantitative polymerase chain reaction prior to iodine‑131 treatment. The association of the variation of target genes with susceptibility to early‑stage hypothyroidism was analyzed. Compared with normal subjects, the mRNA expression levels of Ku70 (0.768, vs. 3.304, respectively; P<0.001) and EGFR (0.859, vs. 1.752, respectively; P<0.05) were significantly higher, whereas those of NF‑κB (0.884, vs. 0.578, respectively; P<0.05) and Bcl‑2 (1.235, vs. 0.834, respectively; P<0.05) were lower in the hyperthyroid patients. Following treatment with iodine‑131, 30 of the 59 (50.8%) patients with hyperthyroidism were diagnosed with early‑stage hypothyroidism, and in the early‑stage hypothyroidism group, the mRNA expression levels of Bcl‑2 were significantly decreased (P<0.05), whereas those of Egr‑1 (P<0.05) were significantly increased, compared with the non‑early‑stage hypothyroidism group. The association between the changes in the expression levles of Bcl‑2 and Egr‑1 and susceptibility to early‑stage hypothyroidism was supported by multivariate regression analysis. No significant changes in the expression levels of the other target genes were detected. The opposing changes in the mRNA expression levels of Bcl‑2 and Egr‑1 in patients with early‑stage hypothyroidism indicates their potential as prognostic markers of early-stage hypothyroidism induced by iodine-131 treatment.

Total thyroid ablation in Graves' orbitopathy

Graves' orbitopathy (GO) is an autoimmune condition almost always associated with autoimmune thyroid disease, especially Graves' disease (GD). According to the most widely accepted model, the autoantigens responsible for GO would include molecules expressed by thyroid epithelial cells that are present also in orbital tissues. The high likelihood that the etiologies of GO and of the underlying autoimmune thyroid diseases are somehow linked is confirmed by the very close relationship between GO, the onset and the course of Graves' diseases, the size of the thyroid gland, and most importantly, thyroid function and thyroid treatment. Based on these considerations, it has been proposed that complete removal of thyroid antigens and of thyroid infiltrating lymphocytes, the so-called total thyroid ablation (TTA), may be followed by an attenuation of the immune reaction against orbital antigens, and ultimately by an amelioration of GO. The possibility that TTA, achieved by near total thyroidectomy followed by radioiodine, may be beneficial for GO was initially suggested by two retrospective studies and more recently by two prospective, randomized clinical trials conducted in patients with moderate GO treated with intravenous glucocorticoids. Although there seemed to be no difference in the long term, compared with near total thyroidectomy alone TTA was associated with a shorter time required for GO to improve, or anyway to reach its best possible outcome, and with a lesser requirement for additional treatments for GO to improve. Whether this is sufficient to offer ablation to patients remains a matter of discussion. At present, this procedure could be offered only to patients scheduled to thyroidectomy and glucocorticoid treatment.

Thyroid surgery for treatment of Graves' disease complicated by ophthalmopathy: a comprehensive review

Graves' disease (GD) is an autoimmune disorder in which antibodies directed against thyroid-stimulating hormone receptors leads to thyrotoxicosis. Graves' ophthalmopathy, a condition that occurs in up to half of GD patients, is a cause of significant morbidity and is potentially vision threatening. Three treatment options are equally effective for uncomplicated GD and these include thyroid surgery (thyroidectomy), radioactive iodine thyroid ablation and antithyroid drugs. However, recent practice surveys suggest that surgery is the least favored GD treatment. When GD is complicated by moderate-to-severe Graves' ophthalmopathy, antithyroid drugs and surgery are recommended by current guidelines, and again the preference for thyroid surgery in these cases has remained low. This report aims to review current published data regarding thyroidectomy as a treatment for GD, and in particular, we focus on the effects of thyroidectomy on Graves' ophthalmopathy development and progression.

Total thyroidectomy as a method of choice in the treatment of Graves' disease - analysis of 1432 patients

Background

Graves’ disease represents an autoimmune disease of the thyroid gland where surgery has an important role in its treatment. The aim of our paper was to analyze the results of surgical treatment, the frequency of microcarcinoma and carcinoma, as well as to compare surgical complications in relation to the various types of operations performed for Graves’ disease.

Methods

We analysed 1432 patients (221 male and 1211 female) who underwent surgery for Graves’ disease at the Centre for Endocrine Surgery in Belgrade during 15 years (1996–2010). Average age was 34.8 years. Frequency of surgical complications within the groups was analyzed with nonparametric Fisher’s test.

Results

Total thyroidectomy (TT) was performed in 974 (68%) patients, and Dunhill operation (D) in 221 (15.4). Carcinoma of thyroid gland was found in 146 patients (10.2%), of which 129 (9%) were a microcarcinoma. Complication rates were higher in the TT group, where there were 31 (3.2%) patients with permanent hypoparathyroidism, 9 (0.9%) patients with unilateral recurrent nerve paralysis and 10 (1.0%) patients with postoperative bleeding. Combined complications, such as permanent hypoparathyroidism with bleeding were more common in the D group where there were 2 patients (0,9%), while unilateral recurrent nerve paralysis with bleeding was more common in the TT group where there were 3 cases (0,3%).

Conclusions

Frequency of complications were not significantly statistically different in relation to the type of surgical procedure. Total thyroidectomy represents a safe and efficient method for treating patients with Graves’ disease, and it is not followed by a greater frequency of complications in relation to less extensive procedures.

Predictive factors of outcomes in personalized radioactive iodine ((131)I) treatment for Graves' disease

BACKGROUND

Graves' disease (GD) is the most common cause of hyperthyroidism in iodine-sufficient areas. Radioactive iodine I treatment (RIT), as the 1st therapeutic option, is widely accepted by doctors and patients. The aim of this study was to investigate factors influencing the success rate of calculated RIT in GD.

METHODS

Thyroid function outcome (hyperthyroidism or euthyroidism/hypothyroidism) was verified retrospectively at least 1 year after RIT and was compared with presenting clinical characteristics and pre-RIT parameters in 167 patients with GD treated with I-iodide in the authors' institute.

RESULTS

After RIT, 83 patients (49.7%) became euthyroid, 64 patients (38.3%) became hypothyroid and 20 (12.0%) remained hyperthyroid. Multiple logistic regression analyses demonstrated that there was no statistically significant association between RIT outcomes and sex, age, history of GD, previous antithyroid drug treatment, thyroid hormone levels, thyroid gland mass or radioactive iodine I dosage. The only variables associated with the success rate were the course of disease over 6 months (odds ratio, 3.70; confidence interval, 1.75-7.17; P = 0.014) and 2-hour radioactive iodine uptake (RAIU) >58.5% (odds ratio, 4.08; confidence interval, 2.03-7.83; P = 0.005).

CONCLUSIONS

Our study has shown that a calculated approach for the treatment of GD was effective, but high failure rates were observed in patients presenting higher 2-hour RAIU, particularly those with 2-hour RAIU of more than 58.5%.

Long-Term Effect of Surgery in Graves' Disease: 20 Years Experience in a Single Institution

The present study compared the long-term outcome of subtotal thyroidectomy (ST) to that of total thyroidectomy (TT) in Graves' disease (GD). Patients with GD requiring surgery were divided between two groups: ST and TT. Postoperative thyroid function (PoTF) changes, including hypothyroidism, euthyroidism, and hyperthyroidism, and surgical complications were analyzed 3 months and 2 years after surgery. During the study period, 350 GD patients underwent surgery, of whom 254 underwent ST and 96 underwent TT. In the ST group, the rates of hypothyroidism, euthyroidism, and hyperthyroidism were 92.5%, 6.7%, and 0.4%, respectively, after 3 months, and 86.1%, 8.6%, and 5.3%, respectively, after 2 years. No difference in the rate of surgical complication was observed between the ST and TT groups (p = 0.089). Most of the ST patients showed hypothyroidism after surgery, and euthyroidism was rare. The long-term outcome of ST included noticeable PoTF changes and recurrence of GD. These results suggest that TT should be considered as a treatment option in GD requiring surgery.

Comparison of clinical outcome after a fixed dose versus dosimetry-based radioiodine treatment of Graves' disease: Results of a randomized controlled trial in Indian population

OBJECTIVE

Two approaches are used to treat Graves' disease with radioiodine ((131)I)-the fixed dose approach and the other based on dosimetry. A prospective study was performed to compare the results of these two approaches in a randomized patient population, as such study is lacking in the Indian population till date.

MATERIALS AND METHODS

Patients with Graves' disease were randomized into two groups: (1) Fixed dose group and the (2) Calculated dose group, each comprising of 20 patients. All the patients underwent detailed clinical and biochemical evaluation. Thyroid mass was determined by high resolution ultrasound machine with linear transducer of 7-11 MHz. Patients were given 185-370 kBq (5-10 uCi) of (131)I and 24 hr radioiodine uptake (RAIU) was calculated using thyroid uptake probe and thyroid phantom. Fixed dose group patients were administered 185MBq of (131)I. Calculated dose group patients were given (131)I as per the following formula: Calculated dose = [3700 kBq/g × estimated thyroid wt. (g)] ÷ 24 hr RAIU (%). Success of first dose of radioiodine was defined as clinically/biochemically euthyroid/hypothyroid status at the end of 3 months without the need for further therapy.

RESULTS

In the fixed dose group, eight patients were hyperthyroid, four were euthyroid, and eight were hypothyroid after the first dose at 3 months. Success rate of first dose was 60%. In calculated dose group, seven patients were hyperthyroid, eight were euthyroid, and five were hypothyroid. Success rate of first dose was 65%.

CONCLUSIONS

There is no statistically significant difference between the success rates of the two methods at 3 months. Hence, fixed dose approach may be used for treatment of Graves' disease as it is simple and convenient for the patient. Longer follow-up with higher number of patients should be done to confirm or contradict our findings.

Management of Graves' disease: an overview and comparison of clinical practice guidelines with actual practice trends

Over the last century, much has been learned about the pathogenesis, manifestations, and management of Graves' disease leading to the establishment of evidence-based clinical practice guidelines. The joint clinical practice guidelines from the American Thyroid Association and the American Association of Clinical Endocrinologists give recommendations on both the diagnosis and treatment of hyperthyroidism. A survey of clinicians performed that same year, however, revealed that current practices diverge from these recently published guidelines in multiple areas. These differences will need to be assessed serially to determine the impact of the guidelines on future clinical practice and perhaps vice versa.

Thyroidectomy as primary treatment optimizes body mass index in patients with hyperthyroidism

OBJECTIVE

The purpose of this study was to determine how the timing of thyroidectomy influenced postoperative weight change.

METHODS

We conducted a two-institution study, identifying patients treated with total thyroidectomy for hyperthyroidism. Patients were classified as 'early' if they were referred for surgery as the first treatment option, or 'delayed' if they were previously treated with radioactive iodine (RAI). Groups were compared with the Student's t-test or χ (2) test where appropriate.

RESULTS

There were 204 patients undergoing thyroidectomy for hyperthyroidism. Of these, 171 patients were classified as early and 33 were classified as delayed. Overall, patients gained 6.0 % ± 0.8 of their preoperative body weight at last follow-up. Preoperative body mass indexes (BMIs) were similar between groups (p = 0.98), and the median follow-up time was 388 days (range 15-1,584 days). Both groups gained weight until they achieved a normal thyroid-stimulating hormone (TSH) postoperatively. After achieving a normal TSH, the early group stabilized or lost weight (-0.2 lbs/day), while the delayed group continued to gain weight (0.02 lbs/day; p = 0.61). At last follow-up, there were significantly more patients in the delayed group who increased their BMI category compared with the early group (42.4 vs. 21.6 %; p = 0.01). Twice as many patients in the delayed group moved up or into an unhealthy BMI category (overweight or obese) compared with the early group (39.4 vs. 19.3 %; p = 0.01).

CONCLUSIONS

Compared with patients initially treated with RAI, patients with hyperthyroidism who underwent surgery as the first treatment were less likely to become overweight or obese postoperatively.

Diagnosis and management of Graves disease: a global overview

Graves disease is an autoimmune disorder characterized by goitre, hyperthyroidism and, in 25% of patients, Graves ophthalmopathy. The hyperthyroidism is caused by thyroid hypertrophy and stimulation of function, resulting from interaction of anti-TSH-receptor antibodies (TRAb) with the TSH receptor on thyroid follicular cells. Measurements of serum levels of TRAb and thyroid ultrasonography represent the most important diagnostic tests for Graves disease. Management of the condition currently relies on antithyroid drugs, which mainly inhibit thyroid hormone synthesis, or ablative treatments ((131)I-radiotherapy or thyroidectomy) that remove or decrease thyroid tissue. None of these treatments targets the disease process, and patients with treated Graves disease consequently experience either a high rate of recurrence, if receiving antithyroid drugs, or lifelong hypothyroidism, after ablative therapy. Geographical differences in the use of these therapies exist, partially owing to the availability of skilled thyroid surgeons and suitable nuclear medicine units. Novel agents that might act on the disease process are currently under evaluation in preclinical or clinical studies, but evidence of their efficacy and safety is lacking.

Total Thyroidectomy as Primary Definitive Treatment for Graves’ Hyperthyroidism

The objective of this study was to compare the results of total thyroidectomy (TT) for hyperthy-roidism secondary to Graves’ disease (GD) with TT for other benign thyroid diseases to determine if TT should be considered more often as first-line therapy for GD. Seven hundred eighty patients underwent TT for benign disease: 203 for GD, 56 for other hyperthyroidisms, and 521 for other benign diseases from March 1, 2003, to December 31, 2009. The perioperative results of these three groups were compared for demographics, blood loss, operative time, complications, and hospitalization. There were no significant differences among the three groups except the patients with GD were more likely to be younger (42 vs 56 vs 57 years; P < 0.001), have more blood loss (154 vs 99 vs 110 mL; P = 0.05), and were more likely to develop permanent hypoparathyroidism (1.0 vs 1.8 vs 0%; P = 0.03) when compared with other causes of hyperthyroidism and other benign thyroid diseases. Permanent recurrent laryngeal nerve injury did not occur in the GD group (0 vs 0 vs 0.4% nerves at risk; P = 0.69) with transient recurrent laryngeal nerve injury occurring in 1.7 versus 2.7 versus 3.1 per cent nerves at risk ( P = 0.35). The lack of a euthyroid state preoperatively had no influence on surgical outcomes or complications. Eighty percent of the TTs for GD were done as same-day outpatient procedures. TT offers a safe, low-risk, and rapid cure for GD to justifiably be considered as a reasonable first-line therapy in selected patients with Graves’ hyperthyroidism.

Antithyroid drugs and their analogues: synthesis, structure, and mechanism of action

Thyroid hormones are essential for the development and differentiation of all cells of the human body. They regulate protein, fat, and carbohydrate metabolism. In this Account, we discuss the synthesis, structure, and mechanism of action of thyroid hormones and their analogues. The prohormone thyroxine (T4) is synthesized on thyroglobulin by thyroid peroxidase (TPO), a heme enzyme that uses iodide and hydrogen peroxide to perform iodination and phenolic coupling reactions. The monodeiodination of T4 to 3,3',5-triiodothyronine (T3) by selenium-containing deiodinases (ID-1, ID-2) is a key step in the activation of thyroid hormones. The type 3 deiodinase (ID-3) catalyzes the deactivation of thyroid hormone in a process that removes iodine selectively from the tyrosyl ring of T4 to produce 3,3',5'-triiodothyronine (rT3). Several physiological and pathological stimuli influence thyroid hormone synthesis. The overproduction of thyroid hormones leads to hyperthyroidism, which is treated by antithyroid drugs that either inhibit the thyroid hormone biosynthesis and/or decrease the conversion of T4 to T3. Antithyroid drugs are thiourea-based compounds, which include propylthiouracil (PTU), methimazole (MMI), and carbimazole (CBZ). The thyroid gland actively concentrates these heterocyclic compounds against a concentration gradient. Recently, the selenium analogues of PTU, MMI, and CBZ attracted significant attention because the selenium moiety in these compounds has a higher nucleophilicity than that of the sulfur moiety. Researchers have developed new methods for the synthesis of the selenium compounds. Several experimental and theoretical investigations revealed that the selone (C═Se) in the selenium analogues is more polarized than the thione (C═S) in the sulfur compounds, and the selones exist predominantly in their zwitterionic forms. Although the thionamide-based antithyroid drugs have been used for almost 70 years, the mechanism of their action is not completely understood. Most investigations have revealed that MMI and PTU irreversibly inhibit TPO. PTU, MTU, and their selenium analogues also inhibit ID-1, most likely by reacting with the selenenyl iodide intermediate. The good ID-1 inhibitory activity of PTU and its analogues can be ascribed to the presence of the -N(H)-C(═O)- functionality that can form hydrogen bonds with nearby amino acid residues in the selenenyl sulfide state. In addition to the TPO and ID-1 inhibition, the selenium analogues are very good antioxidants. In the presence of cellular reducing agents such as GSH, these compounds catalytically reduce hydrogen peroxide. They can also efficiently scavenge peroxynitrite, a potent biological oxidant and nitrating agent.

Total thyroidectomy vs bilateral subtotal thyroidectomy in patients with Graves' diseases: a meta-analysis of randomized clinical trials

BACKGROUND

Conducting total thyroidectomy (TT) or subtotal thyroidectomy (ST) in patients with Graves' disease remains controversial. We performed a meta-analysis based on the published randomized controlled trials to evaluate the complications of TT vs ST.

METHODS

We searched multiple electronic databases for prospective, randomized, controlled trials related to safety and effectiveness of TT vs ST. Relative risk (RR) was estimated with 95% confidence interval (CI) based on an intention-to-treat analysis. We considered the following outcomes: recurrent hyperthyroidism, ophthalmopathy progression, temporary and permanent hypoparathyroidism, temporary and permanent recurrent laryngeal nerve palsy (RLNP) and post-operative bleeding.

RESULTS

Four trials with 674 patients (342 with TT, 332 with ST) were analysed. Although the overall rates of ophthalmopathy progression were similar between TT and ST (RR 0·92, 95% CI = 0·50-1·71; P = 0·80), TT was associated with a significant reduction in recurrent hyperthyroidism (RR 0·14, 95% CI = 0·05-0·41; P < 0·01). The pooled RR of post-operative bleeding for TT was similar to that for ST (RR 0·32, 95% CI = 0·05-1·96; P = 0·22). However, comparing with ST, the RR of temporary hypoparathyroidism was significantly higher for TT (RR 2·66, 95% CI = 1·89-3·73; P < 0·01). There was no significant difference in permanent hypoparathyroidism (RR 2·30, 95% CI = 0·78-6·76; P = 0·13), temporary (RR 1·08, 95% CI = 0·47-2·48; P = 0·85) and permanent RLNP (RR 1·54, 95% CI = 0·41-5·73; P = 0·52) between the two groups.

CONCLUSIONS

With regard to ophthalmopathy progression, post-operative bleeding, permanent hypoparathyroidism, temporary and permanent RLNP, TT is consistent with ST in patients with Graves' disease. However, TT is associated with a reduced incidence of recurrent hyperthyroidism and results in an increase in temporary hypoparathyroidism. Therefore, TT should be proposed for the treatment of Graves' disease.

Total thyroidectomy for safe and definitive management of Graves' disease

Background:

The role of total thyroidectomy in the management of patients with Graves' disease remains controversial. However, there is increasing evidence to support the role of the procedure as a safe and definitive treatment for Graves' disease.

Method:

Patients were identified from a prospective thyroid database of the multidisciplinary thyroid clinic at Hull Royal Infirmary. All case notes were independently reviewed to confirm the data held on the database.

Results:

Over a 7-year period, the senior author has performed 206 total thyroidectomies for Graves' disease. The incidence of temporary recurrent laryngeal nerve palsy and hypoparathyroidism was 3.4 per cent and 24 per cent respectively. There was one case of permanent unilateral recurrent laryngeal nerve palsy, and 3.9 per cent of patients developed permanent hypoparathyroidism. There has been no relapse of thyrotoxicosis.

Conclusion:

In the context of a multidisciplinary thyroid clinic, total thyroidectomy should be offered as a safe and effective first-line treatment option for Graves' disease.

Thyrotoxicosis and radioiodine therapy: Does the dose matter?

There are 3 treatment options for thyrotoxicosis: Antithyroid drugs, Surgery and radioiodine. The choice of treatment varies geographically. Radioiodine therapy is preferred in the United States. The aim of radioiodine is to destroy sufficient thyroid tissue to cure the hyperthyroidism. There is a lack of consensus towards what dose of radioiodine should be used. Several methods are used to determine the dose. In our practice we administer 400 MBq to patients with Graves and in patients with large multinodular goiter, we would administer 800 MBq.

A 2011 survey of clinical practice patterns in the management of Graves' disease

CONTEXT

More than two decades have passed since members from the American Thyroid Association (ATA), European Thyroid Association, and Japan Thyroid Association were surveyed on management practices for patients with hyperthyroidism due to Graves' disease (GD).

OBJECTIVE

We sought to document current practices in the management of GD and compare these results both to those documented in earlier surveys and to practice recommendations made in the 2011 ATA/American Association of Clinical Endocrinologists (AACE) hyperthyroidism practice guidelines. Lastly, we sought to examine differences in GD management among international members of U.S.-based endocrine societies.

METHODS

Members of The Endocrine Society (TES), ATA, and AACE were invited to participate in a web-based survey dealing with testing, treatment preference, and modulating factors in patients with GD.

RESULTS

A total of 730 respondents participated in the survey, 696 of whom completed all sections. Respondents included 641 TES members, 330 AACE members, and 157 ATA members. The preferred mode of therapy in uncomplicated GD was antithyroid drugs (ATDs) by 53.9% of respondents, radioactive iodine (RAI) therapy by 45.0%, and thyroid surgery in 0.7%. Compared with 1991, fewer U.S. (59.7 vs. 69%) and European (13.3% vs. 25%) respondents would use RAI therapy. Methimazole and carbimazole were the preferred ATDs, with only 2.7% of respondents selecting propylthiouracil. Patients with Graves' ophthalmopathy were treated with ATDs (62.9%) or surgery (18.5%) and less frequently with RAI plus corticosteroids (16.9%) or RAI alone (1.9%).

CONCLUSIONS

Striking changes have occurred in the management of GD over the past two decades, with a shift away from RAI and toward ATDs in patients with uncomplicated GD. Apparent international differences persist but should be interpreted with caution. Current practices diverge in some areas from recently published guidelines; these differences should be assessed serially to determine the impact of the guidelines on future clinical practice.

Increasing use of radioiodine in young people with thyrotoxicosis in Great Britain

OBJECTIVE

Radioiodine (RI) is an important therapeutic option in young patients with thyrotoxicosis. We wanted to determine whether RI is being used more frequently in this age group.

DESIGN

National survey of Great Britain (England, Wales and Scotland).

METHODS

Sixty-one medical physics departments were asked to provide the age and number of patients with thyrotoxicosis <21 years treated with RI (1990-2008). Information on the total number of RI treatments for thyrotoxicosis was also collected.

RESULTS

Forty-three departments (70%), with representation from 21 of the 25 most populous areas of Great Britain, provided data on 69,258 treatments. The number of treatments recorded on patients <21 years during this period was 560 (0.9%). The frequency of treatments in young people as a percentage of the total increased from 0.2% in 1990 to 1.5% in 2008 (P<0.001). When the 18 centres submitting at least 17 years of data were analysed, a similar pattern was observed. The maximum number of young people treated was greatest in 2008 (62) with a fall in the youngest age at which RI was administered from 18 years (1990) to 11 years (2008).

CONCLUSIONS

A rising proportion of patients with thyrotoxicosis receiving RI are in those <21 years. This is largely due to an increase in the number of young people treated with a reduction in the minimum age at RI administration. We suspect that European clinicians are becoming more comfortable with RI treatment in young people with thyrotoxicosis, although a changing incidence is a potential contributing factor.

Radioiodine thyroid ablation in graves' hyperthyroidism: merits and pitfalls

Ablative approaches using radioiodine are increasingly proposed for the treatment of Graves′ disease (GD) but their ophthalmologic and biological autoimmune responses remain controversial and data concerning clinical and biochemical outcomes are limited. The aim of this study was to evaluate thyroid function, TSH-receptor antibodies (TRAb) and Graves′ ophthalmopathy (GO) occurrence after radioiodine thyroid ablation in GD. We reviewed 162 patients treated for GD by iodine-131 (¹³¹I) with doses ranging from 370 to 740 MBq, adjusted to thyroid uptake and sex, over a 6-year period in a tertiary referral center. Collected data were compared for outcomes, including effectiveness of radioiodine therapy (RIT) as primary endpoint, evolution of TRAb, and occurrence of GO as secondary endpoints. The success rate was 88.3% within the first 6 months after the treatment. The RIT failure was increased in the presence of goiter (adjusted odds ratio = 4.1, 95% confidence interval 1.4–12.0, P = 0.010). The TRAb values regressed with time (r = −0.147; P = 0.042) and patients with a favorable outcome had a lower TRAb value (6.5 ± 16.4 U/L) than those with treatment failure (23.7 ± 24.2 U/L, P < 0.001). At the final status, 48.1% of patients achieved normalization of serum TRAb. GO occurred for the first time in 5 patients (3.7%) who were successfully cured for hyperthyroidism but developed early and prolonged period of hypothyroidism in the context of antithyroid drugs (ATD) intolerance (P = 0.003) and high TRAb level (P = 0.012). On the basis the results of this study we conclude that ablative RIT is effective in eradicating Graves’ hyperthyroidism but may be accompanied by GO occurrence, particularly in patients with early hypothyroidism and high pretreatment TRAb and/or ATD intolerance. In these patients, we recommend an early introduction of LT4 to reduce the duration and the degree of the radioiodine-induced hypothyroidism.

The propylthiouracil dilemma

PURPOSE OF REVIEW

To bring to the attention of healthcare professionals the additional information on propylthiouracil (PTU)-related hepatotoxicity, based on a reanalysis of medical files reported to the Food and Drug Administration (1982-2008) for acute liver failure in PTU-treated hyperthyroid patients, and propose recommendations for the clinical use of PTU. Thirteen files of PTU-related severe liver adverse effects were analyzed for the pediatric population, seventeen for nonpregnant adults and two for pregnant women.

RECENT FINDINGS

The recent findings showed that the daily PTU dose administered was high in the children, with a mean of 300 mg/day for an average 10-year-old individual. With regard to treatment duration, PTU administration lasted for at least 4 months in 75% of pediatric cases. Similarly, in a majority of adult cases (64%), PTU-induced liver injury occurred after a relatively long treatment period (4 months to >1 year).

SUMMARY

PTU should not be used in children, in whom methimazole (MMI) represents the logical alternative. In adults, PTU should be restricted to those rare patients with Graves' disease for whom no better alternative can be offered and in patients with thyroid storm. For the special circumstance of pregnancy, PTU is the preferred choice during early gestation; switching back to MMI during later gestational stages remains a matter of clinical judgment. It is unknown whether liver function tests monitoring is worthwhile to prevent life-threatening, PTU-related hepatotoxicity.

Cancer risk after medical exposure to radioactive iodine in benign thyroid diseases: a meta-analysis

Radioiodine-131 ((131)I) is widely used for diagnosis and treatment of benign thyroid diseases. Observational studies have not been conclusive about the carcinogenic potential of (131)I and we therefore conducted a meta-analysis. We performed a literature search till September 2011 which included (131)I as a diagnostic or treatment modality ((131)I for treatment of thyroid cancer was excluded). Data on 64 different organ or organ group subsets comprising 22 029 exposed subjects in the therapeutic cohorts and 24 799 in the diagnostic cohorts in seven studies were included. Outcome was pooled as the relative risk (RR) using both standard and bias adjusted methods. Quality assessment was performed using a study-specific instrument. No increase in overall (RR 1.06, 95% CI: 0.94-1.19), main organ group or combined organ group (four groups known to concentrate (131)I; RR 1.11, 95% CI: 0.94-1.31) risks was demonstrable. Individual organs demonstrated a higher risk for kidney (RR 1.70, 95% CI: 1.15-2.51) and thyroid (RR 1.99, 95% CI: 1.22-3.26) cancers with a strong trend for stomach cancer (RR 1.11, 95% CI: 0.92-1.33). A thyroid dose effect was seen for diagnostic doses. While there is no increase in the overall burden of cancer, an increase in risk to a few organs is seen which requires substantiation. The possible increase in thyroid cancer risk following diagnostic (131)I use should no longer be of concern given that it has effectively been replaced by the use of 99mTc-pertechnetate.

Geriatric thyroidology: An update

Thyroid anatomy and physiology change in the elderly with age-related fibrosis and atrophy in the thyroid gland and changes in thyroid hormones. The incidence of thyroid nodules increases with age, making the thyroid more nodular. Hypothyroidism is common in the elderly and, if untreated, is associated with significant morbidity. Elderly patients are sensitive to iatrogenic hyperthyroidism, especially with preexisting cardiac disease. Hence, treatment of hypothyroidism should be individualized and should be started with low doses and titrated according to response. Hyperthyroidism, although less common in the elderly if present, is associated with significant cardiac morbidity and mortality. Radioiodine therapy is considered a safe primary treatment in the elderly with hyperthyroidism. Management of subclinical hypo- and hyperthyroidism is still controversial. The incidence of thyroid tumors increase with age. Thyroid malignancy in the elderly is considered as a more advanced disease compared with the young, and aggressive management is recommended.

Disparity in the management of Graves' disease observed at an urban county hospital: a decade-long experience

BACKGROUND

The objective of this study was to determine whether health care disparities exist in management of Graves' disease.

METHODS

Patients treated for Graves' disease from 1999 to 2009 were divided into medical and surgical treatment groups. A comparative analysis of age, sex, race, health insurance, and income was completed. Address and/or zip code were geocoded and median income was determined from census data.

RESULTS

A total of 634 patients were treated for Graves' disease; 535 (84%) medically and 99 (16%) surgically. Mean age (40 ± 15 vs 43 ± 11 y), percentage of women (84% vs 91%), and racial distribution were similar in the 2 groups (P > .05). In the surgical group, median income was lower ($31,530 vs $34,404; P = .07) and 52% of patients were uninsured compared with 30% of patients treated medically (P < .0001).

CONCLUSIONS

A disproportionate number of uninsured patients underwent thyroidectomy for Graves' disease. Social and economic factors may have a role in determining definitive therapy for Graves' disease.

Functional capacity of the thyroid autograft and heterograft: An experimental study

BACKGROUND

The aim of this study was to investigate the functional capacity of thyroid autografts/heterografts in a guinea pig model.

METHODS

A total of 24 guinea pigs were divided into 4 groups. Group A had only a thyroidectomy incision, and group B had total thyroidectomy. We performed autotransplantation in group C and heterotransplantation in group D. We monitored the guinea pigs for an 8-week period, with weekly measurements of free triiodothyronine (fT3), free thyroxine (fT4), and thyroid-stimulating hormone (TSH). At the final stage, the autografts/heterografts were histologically examined.

RESULTS

In group B, fT3/fT4 showed a gradual decrease; however, an increase of TSH was noted. In groups C and D, fT3/fT4 showed a gradual decrease, followed by a gradual increase until euthyroid levels; an exact opposite was noted for TSH. In histologic examination, there were functional thyroid follicles in all animals of groups C and D.

CONCLUSIONS

The autotransplanted/heterotransplanted guinea pig's thyroid tissue provides adequate thyroid function.

The dilemma of how to manage Graves' hyperthyroidism in patients with associated orbitopathy

CONTEXT

Graves' orbitopathy (GO) is present in about 50% of patients with Graves' hyperthyroidism. It may range from mild to moderately severe and (rarely) to sight-threatening. Whether antithyroid drugs (ATDs), radioactive iodine (RAI), or thyroidectomy should be the treatment of choice in the presence of overt and active GO is a matter of debate.

EVIDENCE ACQUISITION

The major source of data acquisition included PubMed search strategies. Articles published in the last 30 yr were screened. Furthermore, the bibliographies of relevant citations and chapters of major textbooks were evaluated for any additional appropriate citation.

EVIDENCE SYNTHESIS

Prompt restoration and stable maintenance of euthyroidism is important for the course of GO. ATDs and thyroidectomy per se do not influence the natural history of GO. RAI can cause progression or de novo development of GO, particularly in smokers. This effect can be prevented by oral steroid prophylaxis. In patients with mild orbitopathy, the choice of thyroid treatment is largely independent of GO. Moderate-to-severe and active GO should be treated without delay. Whether in these patients, concomitant treatment of hyperthyroidism should be conservative (ATDs) or ablative (RAI, thyroidectomy, or both) is presently based on expert opinion rather than evidence. Emerging and potentially interesting biological agents, such as rituximab, counteracting pathogenic mechanisms of both hyperthyroidism and GO, need to be evaluated in randomized clinical trials.

CONCLUSIONS

The choice of the optimal treatment for hyperthyroidism in patients with moderate-to-severe and active GO remains unsettled and is mainly based on personal experience. Randomized clinical trials in this field are eagerly needed.

Glucocorticoid administration for Graves' hyperthyroidism treated by radioiodine. A questionnaire survey among members of the European Thyroid Association

BACKGROUND

Glucocorticoid prophylaxis is required in some instances after radioiodine (RAI) treatment for Graves' hyperthyroidism to prevent progression of Graves' orbitopathy (GO). However, no randomized clinical trial has been performed to ascertain the optimum glucocorticoid therapy.

AIM AND METHODS

Aim of this study was to perform a questionnaire-based survey of glucocorticoid prophylaxis among European thyroidologist members of the European Thyroid Association.

RESULTS

Eighty-two responses from 25 European Countries were received. Two respondents did not prescribe steroids in any clinical scenario, while 8 gave the drug to all patients receiving RAI therapy. The majority of respondents only gave glucocorticoids to patients showing some degree of ocular involvement or if risk factors for the progression of GO after RAI were present (e.g., cigarette smoking); 24% of responses indicated that clinicians would not give glucocorticoids if patients were thought to have no GO or inactive GO. Ninety-one percent of clinicians used prednisone (53%) or prednisolone (38%). The mean starting dose [given for 16 days (range 2-60 days)] was 37.6 mg prednisone or prednisone-equivalent (range 15-80 mg). Overall, the results of this survey showed a wide diversity in the regimens used, in terms of timing of initiation of treatment, duration of treatment, cumulative doses of administered glucocorticoids and monitoring of side-effects of glucocorticoid treatment.

CONCLUSIONS

The results of this study underscore the need for randomized clinical trials to ascertain the optimum regimen of prophylactic glucocorticoid therapy.

Diffusion-weighed MR of the thyroid gland in Graves' disease: assessment of disease activity and prediction of outcome

RATIONALE AND OBJECTIVES

To assess the activity and clinical course of Graves' disease with diffusion-weighted magnetic resonance (MR) imaging.

MATERIALS AND METHODS

Fifty-one patients with Graves' disease and 25 volunteers underwent diffusion MR imaging of the thyroid gland using a single shot echo-planar imaging with b-factor of 0, 300 and 600 second/mm(2). The apparent diffusion coefficient (ADC) values of the thyroid gland were calculated. Patients with active Graves' disease included untreated patients at initial diagnosis (n = 12), patients under antithyroid drugs (n = 11), and patients in relapse after withdrawal of therapy (n = 13). Patients with inactive disease had a remission of hyperthyroidism (n = 15).

RESULTS

The mean ADC values of thyroid gland with active Graves' disease was 0.65 +/- 0.03 x 10(-3) mm(2)/second in patients at initial diagnosis, 0.81 +/- 0.02 x 10(-3) mm(2)/second in patients undergoing antithyroid drug and 0.72 +/- 0.07 x 10(-3) mm(2)/second in patients with relapse of hyperthyroidism. The mean ADC of patients with remission was 0.94 +/- 0.03 x 10(-3) mm(2)/second and for normal volunteer was 1.06 +/- 0.08 x 10(-3) mm(2)/second. There was significant difference in the ADC value of patients with active disease and remission (P = .001). The cutoff ADC value used for differentiating patients with active disease from patients with remission was 0.82 x 10(-3) mm(2)/second. The mean ADC value of thyroid gland had positive correlation with thyroid-stimulating hormone (r = 0.87, P = .001) and negative correlation with serum T4 (r = -0.82, P = .001) and serum T3 (r = -0.71, P = .001).

CONCLUSIONS

The ADC value of the thyroid gland is a promising non invasive parameter for diagnosis of different clinical stages of Graves' disease. Hence it can be used to assess the activity and predict the outcome of patients during and after medical treatment.