Relapse following antithyroid drug therapy for Graves' hyperthyroidism

Prediction for recurrence following antithyroid drug therapy for Graves' hyperthyroidism

Objective

A common problem with antithyroid drugs (ATD) treatment in patients with Graves' disease (GD) is the high recurrence rate after drug withdrawal. Identifying risk factors for recurrence is crucial in clinical practice. We hereby prospectively analyze risk factors for the recurrence of GD in patients treated with ATD in southern China.

Subjects and methods

Patients who were newly diagnosed with GD and aged > 18 years were treated with ATD for 18 months and followed up for 1 year after ATD withdrawal. Recurrence of GD during follow-up was assessed. All data were analyzed by Cox regression with P values < 0.05 considered statistically significant.

Results

A total of 127 Graves' hyperthyroidism patients were included. During an average follow-up of 25.7 (standard deviation = 8.7) months, 55 (43%) had a recurrence within 1 year after withdraw of anti-thyroid drugs. After adjustment for potential confounding factors, the significant association remained for the presence of insomnia (hazard ratio (HR) 2.94, 95% confidence interval (CI) 1.47-5.88), greater goiter size (HR 3.34, 95% CI 1.11-10.07), higher thyrotrophin receptor antibody (TRAb) titer (HR 2.66, 95% CI 1.12-6.31) and a higher maintenance dose of methimazole (MMI) (HR 2.14, 95% CI 1.14-4.00).

Conclusion

Besides conventional risk factors (i.e., goiter size, TRAb and maintenance MMI dose) for recurrent GD after ATD withdraw, insomnia was associated with a 3-fold risk of recurrence. Further clinical trials investigating the beneficial effect of improving sleep quality on prognosis of GD are warranted.

Long-term follow-up result of antithyroid drug treatment of Graves' hyperthyroidism in a large cohort

OBJECTIVE

This study evaluated the efficacy of antithyroid drugs (ATDs) and risk factors associated with the recurrence of Graves' hyperthyroidism using a comprehensive retrospective cohort.

METHODS

We included 1829 patients newly diagnosed with Graves' hyperthyroidism, with sufficient follow-up data. Clinical outcomes of the patients and risk factors associated with recurrence-free survival, including the changes in thyrotropin receptor antibody, were evaluated.

RESULTS

The median age of the patients was 44.5 years, and 69% were female. Among the patients, 1235 had a chance to withdraw ATD after a median of 23 (interquartile range (IQR) 17.0-35.5) months of treatment. The first remission rate was 55.6% during a median of 72.7 months of follow-up. After the first recurrence, 95% of patients underwent the second course of ATD treatment for a median of 21.1 (IQR 14.8-31.7) months, and the remission rate was 54.1%. During a median of 67 months of follow-up, 7.7% of patients underwent surgery, and 10.5% underwent radioactive iodine therapy. Approximately 30% were still on ATD therapy for recurrent disease or prolonged low-dose maintenance. Younger age (<45 years), male sex, and fluctuating or smoldering of TRAb levels were independent risk factors of the first recurrence after ATD treatment.

CONCLUSIONS

ATD treatment is an acceptable option for the initial treatment of Graves' hyperthyroidism as well as for recurrent disease. The optimal treatment period for ATD treatment needs to be determined using the individual risk factors of recurrence.

Genotype-phenotype correlations in Graves' disease

Graves' disease (GD) is a heterogeneous autoimmune disease affecting with varying degrees of severity the thyroid gland, orbital tissues and skin. The pathogenesis of GD involves a complex interplay between multiple genetic, environmental and endogenous factors. Although the genetic predisposition to GD is well established, the significance of genotype-phenotype correlations and the role of epigenetic modifications in the disease pathogenesis remains largely unknown. In this review, we provide an up-to-date overview of genotype-phenotype correlations and summarize possible clinical implications of genetic and epigenetic markers in GD patients. We will specifically discuss the association of genetic markers and epigenetic modifications with age of GD onset, severity of Graves' hyperthyroidism and the development of clinically evident Graves' orbitopathy.

Time to Symptom Resolution After Total Thyroidectomy for Graves' Disease

INTRODUCTION

Total thyroidectomy (TT) has been shown to be a safe and effective treatment for Graves' disease. However, the time course for improvement of symptoms has not been defined.

METHODS

With an institutional review board approval, we prospectively gathered survey data of all patients (n = 79) undergoing TT for Graves' disease at a single institution from 2019 to 2021. After informed consent was obtained, patients completed surveys preoperatively and at 2 wk followed by monthly postoperative visits/phone calls. Patient demographics and survey results were collected and analyzed. Symptom recovery time was evaluated using Kaplan-Meier analysis.

RESULTS

A total of 50 patients completed the survey on postoperative follow-up (response rate 63%). Average age was 38 y (range 12-80 y) and 88% of patients were female. The most common preoperative symptoms were fatigue (90%) and heat/cold intolerance (88%). Tremor (median time to resolution: 1 wk; interquartile range [IQR] 1-3), diarrhea (median 1 wk [IQR 1-3]), and palpitations (median 1 wk [IQR 1-3]) resolved the most rapidly followed by eye symptoms (median 3 wk [IQR 1-6]), heat/cold intolerance (median 3 wk [IQR 3-30]), memory deficits (median 3 wk [IQR 1-undefined]), and fatigue (median: 3 wk [IQR 1-14]). There were no significant differences in time to resolution of symptoms by gender or age (less than versus 40 y and older). Those with uncontrolled Graves' had more severe symptoms but no difference in time to resolution from the euthyroid Graves' patients.

CONCLUSIONS

Many Graves' disease symptoms improve rapidly following TT, with a median time to improvement of less than 1 mo.

Long-term methimazole therapy in Graves' hyperthyroidism and adverse reactions: a Danish multicenter study

Purpose

In this prospective multicenter study with patients newly diagnosed with Graves' hyperthyroidism (GH), we studied the timing and characteristics of adverse drug reactions in patients treated with anti-thyroid drugs (ATD) for up to 48 months.

Methods

Patients with GH were treated with ATD until remission and hereafter with a low-dose regime to keep the patients in remission. The patients were followed with blood samples and recording of adverse events approximately every second month for the first 2 years and every third month for the following 2 years.

Results

We included 208 patients and the patients were treated for a median of 22 (range: 0.5-49) months. Ten percent of the patients experienced adverse drug reactions and 75% of the cases occurred during the first 6 months. After 24 months, the methimazole dose was lowered to 5 mg/day, and after this time point, no further adverse drug reactions were recorded. Skin reactions were the most prominent reaction, comprising 68% of the registered reactions, and no hepatic and bonemarrow affection was recorded.

Conclusion

With this study, we report the frequency, timing of occurrence, and characteristics of adverse drug reactions when treating GH with the ATD drug methimazole for up to 48 months. Long-term low-dose methimazole treatment can be a cost-effective and straightforward treatment option if adverse drug reactions such as severe hepatic and bone marrow affection are kept in mind.

How to manage Graves' disease in women of childbearing potential

The management of Graves' disease (GD) in women of childbearing potential has multiple specific complexities. Many factors are involved, which differ at the various stages from preconception, conception, first trimester, later pregnancy, postpartum and lactation, with both maternal and foetal considerations. The incidence and significance of the risks incurred from antithyroid drugs (ATDs) in pregnancy have been re-evaluated recently and must be balanced against the risks of uncontrolled hyperthyroidism during childbearing years. Contraception is advised until hyperthyroidism is controlled. ATD cessation should be considered in those who are well controlled on low dose therapy before conception and in early pregnancy. Advice on iodine supplementation does not generally differ in those with GD. Radioiodine (RAI) is contraindicated from 6 months preconception until completion of breastfeeding. In all women who have a history of GD, monitoring of TSH receptor antibodies (TRAb) is strongly recommended during pregnancy, and if elevated, foetal monitoring and assessment of thyroid function in the neonate are required. Of note, RAI increases TRAb for up to a year, making this treatment option even less attractive in this patient group. A small amount of ATD is transferred into breast milk but low doses are safe during lactation. Routine periodic thyroid function testing is recommended in remission to detect postpartum GD recurrence. We present our approach to the Clinical Question 'How to manage GD in women of childbearing potential?'

Thyroid Disease in Pregnancy: A Descriptive Review of Guidelines

Importance

Thyroid disorders represent one of the most frequent complications of pregnancy associated with adverse obstetric, fetal, and neonatal outcomes, especially in case of delayed diagnosis and suboptimal management.

Objective

The aim of this study was to review and compare the recommendations of the most recently published guidelines on the diagnosis and management of these common conditions.

Evidence Acquisition

A descriptive review of guidelines from the Endocrine Society, the European Thyroid Association, the Royal Australian and New Zealand College of Obstetricians and Gynecologists, the American Thyroid Association, and the American College of Obstetricians and Gynecologists on thyroid disease in pregnancy was carried out.

Results

There is an overall consensus regarding the diagnosis of overt and subclinical hypothyroidism and hyperthyroidism in pregnancy using the pregnancy-specific reference ranges and the definition of postpartum thyroiditis. The reviewed guidelines unanimously discourage universal screening for thyroid function abnormalities before and during pregnancy and support targeted screening of high-risk patients by measuring serum thyroid-stimulating hormone levels. Moreover, they all highlight the need of treating overt hypothyroidism and hyperthyroidism, not only during pregnancy, but also before conception, suggesting similar management policies and treatment targets. There is also agreement regarding the management of gestational transient hyperthyroidism with hyperemesis gravidarum, suspected fetal thyrotoxicosis, postpartum thyroiditis, and thyroid malignancy. Scanning or treating with radioactive iodine is contraindicated during pregnancy and breastfeeding. On the other hand, there is controversy on the management of subclinical thyroid disease, thyroid function surveillance protocols, and iodine nutrition recommendations. Of note, the American College of Obstetricians and Gynecologists makes some specific recommendations on the treatment of thyroid storm and thyrotoxic heart failure in pregnant women, whereas the American Thyroid Association makes a special reference to the management of women with thyroid cancer.

Conclusions

As the disorders of the thyroid gland affect a significant proportion of pregnant women, it is of paramount importance to develop uniform international evidence-based protocols for their accurate diagnosis and optimal management, in order to safely guide clinical practice and eventually improve perinatal outcomes.

Treating Thyroid Associated Ophthalmopathy in Pediatric Patients

Thyroid associated ophthalmopathy (TAO) is a common extra-thyroid clinical manifestation of Graves' disease. It is an inflammatory disease of the eye and orbital tissues. Up to one-third of pediatric Graves' disease patients could be diagnosed with TAO. The symptoms can be variable with remissions and exacerbations of pediatric Graves' disease, which has negative effects on the quality of life in children. Teprotumumab is a fully human IgG1κ type monoclonal antibody targeting insulin-like growth factor-1 receptor (IGF-1R), and was approved for the treatment of TAO as a "breakthrough therapy" by the FDA in 2020. Nevertheless, the safety and effectiveness have not been established in pediatric patients. IGF-1R plays an important role in human development, which raises concerns of developmental toxicity. As presented in the pharmacology review report, juvenile monkeys were tested in two separate repeated-dose toxicity studies and no NOAEL was identified. Teprotumumab affected the growth, thymus, spleen and decreased the bone growth. Younger animals seemed to be more sensitive to the effects on normal growth and normal thymus. Hearing impairment posed additional risk to the potential pediatric use, especially for school-age children. Considering the nature of the target, Teprotumumab should not be used empirically in children. More efforts would be made for the further development of teprotumumab for pediatric use.

Antithyroid Drug Treatment in Graves' Disease

Graves' disease is associated with thyrotropin (TSH) receptor stimulating antibody, for which there is no therapeutic agent. This disease is currently treated through inhibition of thyroid hormone synthesis or destruction of the thyroid gland. Recurrence after antithyroid drug (ATD) treatment is common. Recent studies have shown that the longer is the duration of use of ATD, the higher is the remission rate. Considering the relationship between clinical outcomes and iodine intake, recurrence of Graves' disease is more common in iodine-deficient areas than in iodine-sufficient areas. Iodine restriction in an iodine-excessive area does not improve the effectiveness of ATD or increase remission rates. Recently, Danish and Korean nationwide studies noted significantly higher prevalence of birth defects in newborns exposed to ATD during the first trimester compared to that of those who did not have such exposure. The prevalence of birth defects was lowest when propylthiouracil (PTU) was used and decreased by only 0.15% when methimazole was changed to PTU in the first trimester. Therefore, it is best not to use ATD in the first trimester or to change to PTU before pregnancy.

Serum TSH level as predictor of Graves' disease recurrence following antithyroid drug withdrawal: A systematic review

Graves’ disease (GD) has a high recurrence rate despite various and adequate treatment. Numerous studies have been performed to identify the predictor of disease recurrence. This report aims to investigate the role of thyroid stimulating hormone (TSH) level as a thyrotropin in predicting the recurrence of Graves’ disease within 1 to 2 years following antithyroid drug (ATD) withdrawal. Literature searching was conducted on PubMed, Scopus, Cochrane, Proquest, EBSCO in August 2019 and Google Scholar in October 2020. The study criteria include the study that evaluates TSH level 4 weeks following ATD withdrawal, with subjects ≥18 years old who are retrospectively or prospectively followed up after 1 to 2 years following ATD withdrawal. Four eligible studies were selected based on inclusion/exclusion criteria, all of which measured TSH level at 4 weeks following ATD withdrawal. All studies had 1 to 2 years follow up. One study was an RCT, two studies were done in prospective cohort and another in retrospective cohort. All studies had comparable validity and applicability. Three out of four studies suggested that low TSH level measured 4 weeks following treatment withdrawal was associated with higher risk of disease recurrence. In conclusion, low TSH level obtained 4 weeks after ATD withdrawal was associated with higher rate of recurrence rate in GD.

Management of thyrotoxicosis during pregnancy

Thyrotoxicosis during pregnancy should be adequately managed and controlled to prevent maternal and fetal complications. The evaluation of thyroid function in pregnant women is challenged by the physiological adaptations associated with pregnancy, and the treatment with antithyroid drugs (ATD) raises concerns for the pregnant woman and the fetus. Thyrotoxicosis in pregnant women is mainly of autoimmune origin, and the measurement of thyroid stimulating hormone-receptor antibodies (TRAb) plays a key role. TRAb helps to distinguish the hyperthyroidism of Graves' disease from gestational hyperthyroidism in early pregnancy, and to evaluate the risk of fetal and neonatal hyperthyroidism in late pregnancy. Furthermore, the measurement of TRAb in early pregnancy is recommended to evaluate the need for ATD during the teratogenic period of pregnancy. Observational studies have raised concern about the risk of birth defects associated with the use of ATD in early pregnancy and challenged the clinical management and choice of treatment.

Changes in Thyroid Peroxidase and Thyroglobulin Antibodies Might Be Associated with Graves' Disease Relapse after Antithyroid Drug Therapy

BACKGROUND

Graves' disease (GD) is an autoimmune thyroid disorder caused by antibodies stimulating the thyrotropin (TSH) receptor. TSH receptor antibody (TRAb) measurement is useful for predicting GD relapse after antithyroid drug (ATD) treatment. However, the association of other thyroid autoantibodies with GD relapse remains obscure.

METHODS

This retrospective study enrolled patients with GD who were initially treated with ATD. TRAb, thyroid peroxidase antibody (TPOAb), and thyroglobulin antibody (TgAb) were measured at the initial diagnosis and at the time of ATD discontinuation.

RESULTS

A total of 55 patients were enrolled. The mean age was 49.7 years, and 39 patients (70.9%) were female. Antibody positivity at diagnosis was 90.9%, 69.1%, and 61.9% for TRAb, TPOAb, TgAb, respectively. Median ATD treatment period was 15.1 months. At the time of ATD withdrawal, TRAb titers decreased uniformly overall. Conversely, TPOAb and TgAb showed various changes. After withdrawal of ATD, 19 patients (34.5%) experienced relapse. No clinical features or laboratory results were significantly related to relapse in the overall patient group. However, in the TPOAb positive group at diagnosis, increasing titer of TPOAb or TgAb after ATD treatment was significantly and independently related to relapse free survival (TPOAb: hazard ratio [HR], 17.99; 95% confidence interval [CI], 1.66 to 195.43; P=0.02) (TgAb: HR, 5.73; 95% CI, 1.21 to 27.26; P=0.03).

CONCLUSION

Changes in TPOAb or TgAb titers during treatment might be useful for predicting relapse after ATD treatment in patients with positive TPOAb at diagnosis.

Dose optimization of lithium to increase the uptake and retention of I-131 in rat thyroid

The present study was undertaken to optimize the dose of lithium, with an aim to increase the retention of I-131 in the thyroid follicles while maintaining the euthyroid state. 24 female Wistar rats weighing 110 ± 20 g were segregated into four groups. Animals in group I were fed standard laboratory feed and water throughout the period of experimentation. Animals in group II, III and IV were additionally fed with lithium in the form of lithium carbonate orally, at a dose of 10 mg/kg body weight, 20 mg/kg body weight, 30 mg/kg body weight respectively. The dose of lithium was started 1 week prior to radioiodine administration and continued thereafter for another 8 days. After 7 days of lithium treatment, 0.48 MBq of carrier-free I-131 was injected intraperitoneally into each rat, of the four groups. I-131 thyroidal uptake and biokinetics, as well as serum TSH, T3, T4 levels were estimated in all the treatment groups. A significant increase in the thyroid and whole body counts was observed after 4 and 24 h of I-131 aministration in lithium treated rats, compared to control animals. An increase in thyroidal effective t_1/2 and serum TSH levels, along with decrease in the levels of serum T3 and T4 was observed with a dose of 20 mg/kg or higher. In Conclusion, a Lithium dose of 10 mg/kg body weight in rats could increase the uptake of I-131 in the thyroid, without disturbing the control circulating levels of thyroid hormones.

Predictors of Initial and Sustained Remission in Patients Treated with Antithyroid Drugs for Graves' Hyperthyroidism: The RISG Study

Purpose. To study predictors of attaining (part 1) and sustaining (part 2) remission in patients with Graves' hyperthyroidism (GH) treated with antithyroid drugs (ATD). Methods. In the prospective first part, the included patients were treated with ATD until a prespecified definition of remission (thyrotropin > 0.4 mU/L and TSH-receptor antibodies (TRAb) ≤ 1. 0 IU/L in a patient receiving a methimazole dose ≤ 5 mg/day, on two occasions two months apart) was met, or for 24 months. In the second part, patients attaining remission in part 1 were randomized to treatment or observation and followed until relapse or for 24 months. Results. 173 patients completed study 1 and 53% attained remission. TRAb and age were the only significant predictors of remission. Patients with baseline TRAb below vs above 10 IU/L attained remission in 63% compared to 39%, and 5 months priorly (p<0.001). In study 2, 96.4% of the patients randomized to treatment (n=33) sustained remission compared to 66% in the observation group (n=33). Treatment arm was the only significant parameter (p<0.001) of sustained remission. Conclusion. Baseline TRAb was prognostic for attaining remission in GH. Consecutive TRAb measurements during treatment were not worthwhile, but a single measurement after 6-8 months in patients with initial TRAb < 10 IU/L could substantially shorten the treatment period in a subgroup of patients. Only 3.6% of the patients in remission experienced relapse during follow-up when treated with a combination of fixed low dose methimazole and L-T4. ClinTrial.gov registration number is  NCT00796913.

Treatment of adult Graves' disease

Treatment strategy in Graves' disease firstly requires recovery of euthyroid status by antithyroid therapy. Treatment modalities, precautions, advantages and side-effects are to be discussed with the patient. No particular treatment modality has demonstrated superiority. Pregnancy or pregnancy project affects choice of treatment and monitoring. Graves' orbitopathy is liable to be aggravated by iodine-131 treatment and requires pre-treatment assessment. Iodine-131 treatment aims at achieving hypothyroidism. Thyroid surgery for Graves' disease should preferably be performed by an expert team. In case of recurrence of hyperthyroidism, the various treatment options should be discussed with the patient. Empiric treatment of thyroid dermopathy uses local corticosteroids in occlusive dressing.

Preconception management of thyroid dysfunction

Uncorrected thyroid dysfunction in pregnancy has well-recognized deleterious effects on foetal and maternal health. The early gestation period is one of the critical foetal vulnerability during which maternal thyroid dysfunction may have lasting repercussions. Accordingly, a pragmatic preconception strategy is key for ensuring optimal thyroid disease outcomes in pregnancy. Preconception planning in women with hypothyroidism should pre-empt and mirror the adaptive changes in the thyroid gland by careful levothyroxine dose adjustments to ensure adequate foetal thyroid hormone delivery in pregnancy. In hyperthyroidism, the goal of preconception therapy is to control hyperthyroidism while curtailing the unwanted side effects of foetal and maternal exposure to antithyroid drugs. Thus, pregnancy should be deferred until a stable euthyroid state is achieved, and definitive therapy with radioiodine or surgery should be considered in women with Graves' disease planning future pregnancy. Women with active disease who are imminently trying to conceive should be switched to propylthiouracil either preconception or at conception in order to minimize the risk of birth defects from carbimazole or methimazole exposure. Optimal strategies for women with borderline states of thyroid dysfunction namely subclinical hypothyroidism, isolated hypothyroxinaemia and thyroid autoimmunity remain uncertain due to the dearth of controlled interventional trials. Future trial designs should aspire to recruit and initiate therapy before conception or as early as possible in pregnancy.

Effect of Goiter Dispersion Formula on Serum Cytokines in Hyperthyroidism Patients with Neurologic Manifestations of Graves' Disease: A Randomized Trial on 80 Cases

PURPOSE

This study is aimed to explore the combined use of goiter dispersion formula and antithyroid drugs in the treatment of patients with neurologic manifestations of Graves' disease by examining its modulating effects on patients' cytokines.

METHODS

A total of 80 patients with Graves' disease were randomly divided into treatment and control groups. Patients of the treatment group received goiter dispersion formula and antithyroid drugs (methimazole or propylthiouracil), whereas those of the control group received antithyroid drug alone. FT3, FT4, and TSH contents were detected by chemiluminescence immunoassay at pre- and post-treatment; interleukin (IL)-2, IL-8, and IL-17 serum levels before and after the treatment were detected by radioimmunoassay; thyroid B-mode ultrasound and liver and renal function tests were performed in all patients of both groups. An additional cohort of 40 healthy subjects was recruited for baseline measurement.

RESULTS

All the enrolled patients completed the trial. The effective treatment rate was higher in the treatment group than in the control group, of which the difference was statistically significant (treatment group, 95%; control group, 75%, p < 0.01). For blood cytokine, before treatment, IL-2 was reduced whereas IL-8 and IL-17 were increased significantly in both groups of patients with Graves' disease comparing with those in healthy subjects (p < 0.01). For patients of the treatment group, after treatment, their IL-2 levels were increased (p < 0.01) with concomitant decreases in IL-8 and IL-17 levels (p < 0.05). There were no significant changes in blood cytokine levels before and after treatment in the control group.

CONCLUSIONS

Goiter dispersion formula significantly improved the treatment outcomes of antithyroid drug in hyperthyroidism patients with neurologic manifestations of Graves' disease by modulating IL-2, IL-8, and IL-17. The data supported the rationale for the use of goiter dispersion formula in Graves' disease treatment.

Risk of embryopathies with use of antithyroidal medications

PURPOSE OF REVIEW

Hyperthyroidism in pregnant women should be adequately treated to prevent maternal and fetal complications. The treatment of choice in pregnancy is antithyroidal medications (ATDs). The risk of embryopathies associated with the use of Methimazole (MMI) and Propylthiouracil (PTU) in early pregnancy is a matter of clinical attention and concern. This review describes current evidence and how scientific findings are reflected in current clinical guidelines.

RECENT FINDINGS

Embryopathies after the use of ATDs were previously mainly described in case reports and considered rare. Recent large observational studies, including nonexposed control groups, have quantified an increased risk of embryopathies associated with use of ATDs during pregnancy. Findings suggest a risk of embryopathies with the use of both MMI and PTU, but the pattern of embryopathies differs, and embryopathies with the use of PTU appear less severe.

SUMMARY

Current guidelines highlight the need for clinical attention on the use of ATDs in early pregnancy. Patients managed on ATDs for the treatment of hyperthyroidism should be counseled to report a pregnancy as early as possible. PTU is the recommended treatment in early pregnancy, but if the risk of relapse or worsening of hyperthyroidism is considered low, it is suggested that ATD treatment can be withdrawn followed by frequent monitoring of thyroid function.

MANAGEMENT OF ENDOCRINE DISEASE: Arguments for the prolonged use of antithyroid drugs in children with Graves' disease

Graves' disease is an autoimmune disorder. It is the leading cause of hyperthyroidism, but is rare in children. Patients are initially managed with antithyroid drugs (ATDs), such as methimazole/carbimazole. A major disadvantage of treatment with ATD is the high risk of relapse, exceeding 70% of children treated for duration of 2 years, and the potential major side effects of the drug reported in exceptional cases. The major advantage of ATD treatment is that normal homeostasis of the hypothalamus-pituitary-thyroid axis may be restored, with periods of drug treatment followed by freedom from medical intervention achieved in approximately 40-50% of cases after prolonged treatment with ATD, for several years, in recent studies. Alternative ablative treatments such as radioactive iodine and, less frequently and mostly in cases of very high volume goiters or in children under the age of 5 years, thyroidectomy, performed by pediatric surgeons with extensive experience should be proposed in cases of non-compliance, intolerance to medical treatment or relapse after prolonged medical treatment. Ablative treatments are effective against hyperthyroidism, but they require the subsequent administration of levothyroxine throughout the patient's life. This review considers data relating to the prognosis for Graves' disease remission in children and explores the limitations of study designs and results; and the emerging proposal for management through the prolonged use of ATD drugs.

Antithyroid drug therapy in pregnancy: a review of guideline recommendations

The antithyroid drugs, Carbimazole, Methimazole, and Propylthiouracil remain the mainstay of Graves' disease management in pregnancy. A series of Clinical Practice Guidelines aimed at optimising fetal and maternal outcomes in women with Graves' disease have been published in recent years. Areas covered: This review examines existing guideline recommendations on antithyroid drug management of Graves' disease in pregnancy. Expert commentary: Recent guidelines have been shaped by expanding knowledge of the adverse effect profiles of antithyroid drugs on the developing fetus. A core management strategy is to limit fetal exposure to excess thyroid hormones and to curtail adverse drug effects through effective preconception and peri-conception management. Propylthiouracil is the recommended treatment in the first trimester of pregnancy but there is uncertainty regarding antithyroid drug choices in women who continue to require treatment in later pregnancy. Further studies are needed to fully evaluate the risks of congenital anomalies following intrauterine thionamide exposure.

The Second Antithyroid Drug Treatment Is Effective in Relapsed Graves' Disease Patients: A Median 11-Year Follow-Up Study

BACKGROUND

Antithyroid drug (ATD) is a widely used treatment for Graves' disease (GD). However, its long-term efficiency remains unclear. This study investigated the long-term disease prognosis and predictive factors for relapse in ATD-treated GD patients.

METHODS

Newly diagnosed, ATD-treated GD patients with at least four years of follow-up were recruited (n = 187). Remission was defined as maintaining a euthyroid status for more than one year after ATD withdrawal.

RESULTS

During 11.1 years (range 4.0-23.7 years) of median follow-up, overall, 51.9% of the newly diagnosed ATD-treated GD patients achieved remission, 32.1% continued ATD treatment, and 13.4% underwent other ablation treatments. The 10-year remission rates were higher in the first (34.2%) and second (25.5%) ATD courses than in any of the other subsequent ATD courses, and decreased as ATD treatments were repeated. The 10-year relapse rate was the highest after the third ATD treatment (71.4%) compared with that after the first (60.5%) and second (58.3%) courses. Longer duration of ATD treatment (odds ratio [OR] = 1.4 [confidence interval (CI) 1.2-1.7], p < 0.001), higher number of relapses (OR = 4.7 [CI 2.3-9.8], p < 0.001), and moderate to severe Graves' ophthalmopathy (OR = 4.1 [CI 1.1-15.2], p = 0.032) were associated with persistent disease status.

CONCLUSIONS

A second course of ATD can be considered for GD patients after the first relapse because the chance of remission and the relapse rate are similar to the one after the first ATD treatment course. For GD patients with more than two relapses, or with an ATD treatment duration of more than four to five years, low-dose maintenance of ATD or ablative treatment needs to be considered.

2017 Guidelines of the American Thyroid Association for the Diagnosis and Management of Thyroid Disease During Pregnancy and the Postpartum

BACKGROUND

Thyroid disease in pregnancy is a common clinical problem. Since the guidelines for the management of these disorders by the American Thyroid Association (ATA) were first published in 2011, significant clinical and scientific advances have occurred in the field. The aim of these guidelines is to inform clinicians, patients, researchers, and health policy makers on published evidence relating to the diagnosis and management of thyroid disease in women during pregnancy, preconception, and the postpartum period.

METHODS

The specific clinical questions addressed in these guidelines were based on prior versions of the guidelines, stakeholder input, and input of task force members. Task force panel members were educated on knowledge synthesis methods, including electronic database searching, review and selection of relevant citations, and critical appraisal of selected studies. Published English language articles were eligible for inclusion. The American College of Physicians Guideline Grading System was used for critical appraisal of evidence and grading strength of recommendations. The guideline task force had complete editorial independence from the ATA. Competing interests of guideline task force members were regularly updated, managed, and communicated to the ATA and task force members.

RESULTS

The revised guidelines for the management of thyroid disease in pregnancy include recommendations regarding the interpretation of thyroid function tests in pregnancy, iodine nutrition, thyroid autoantibodies and pregnancy complications, thyroid considerations in infertile women, hypothyroidism in pregnancy, thyrotoxicosis in pregnancy, thyroid nodules and cancer in pregnant women, fetal and neonatal considerations, thyroid disease and lactation, screening for thyroid dysfunction in pregnancy, and directions for future research.

CONCLUSIONS

We have developed evidence-based recommendations to inform clinical decision-making in the management of thyroid disease in pregnant and postpartum women. While all care must be individualized, such recommendations provide, in our opinion, optimal care paradigms for patients with these disorders.

Radioactive Iodine Therapy and Glucose Tolerance

Radioactive iodine therapy is commonly used as an adjuvant therapy in follicular and papillary thyroid carcinoma (PTC) and in the treatment of Graves’ disease (GD). The basis of this therapy is the accumulation of radioactive iodine by the sodium-iodide symporter (NIS) in the thyroid gland. Expression of NIS by extrathyroidal tissues such as islets of pancreas has been reported. Radioactive iodine uptake by pancreatic beta-cells can potentially damage these cells. In this study, we discuss the possible associations between radioactive iodine and glucose intolerance. Overall, radioactive iodine uptake by the pancreas may damage beta-cells and predispose patients to glucose intolerance or type 2 diabetes, particularly in patients exposed to radioactive iodine therapy following total thyroidectomy. Further studies are needed to clarify and confirm this association.

Predictive Value of Gene Polymorphisms on Recurrence after the Withdrawal of Antithyroid Drugs in Patients with Graves' Disease

Graves' disease (GD) is one of the most common endocrine diseases. Antithyroid drugs (ATDs) treatment is frequently used as the first-choice therapy for GD patients in most countries due to the superiority in safety and tolerance. However, GD patients treated with ATD have a relatively high recurrence rate after drug withdrawal, which is a main limitation for ATD treatment. It is of great importance to identify some predictors of the higher recurrence risk for GD patients, which may facilitate an appropriate therapeutic approach for a given patient at the time of GD diagnosis. The genetic factor was widely believed to be an important pathogenesis for GD. Increasing studies were conducted to investigate the relationship between gene polymorphisms and the recurrence risk in GD patients. In this article, we updated the current literatures to highlight the predictive value of gene polymorphisms on recurrence risk in GD patients after ATD withdrawal. Some gene polymorphisms, such as CTLA4 rs231775, human leukocyte antigen polymorphisms (DRB1*03, DQA1*05, and DQB1*02) might be associated with the high recurrence risk in GD patients. Further prospective studies on patients of different ethnicities, especially studies with large sample sizes, and long-term follow-up, should be conducted to confirm the predictive roles of gene polymorphism.

ENDOCRINOLOGY IN PREGNANCY: Pregnancy and the incidence, diagnosing and therapy of Graves' disease

Thyroid hormones are essential developmental factors, and Graves' disease (GD) may severely complicate a pregnancy. This review describes how pregnancy changes the risk of developing GD, how early pregnancy by several mechanisms leads to considerable changes in the results of the thyroid function tests used to diagnose hyperthyroidism, and how these changes may complicate the diagnosing of GD. Standard therapy of GD in pregnancy is anti-thyroid drugs. However, new studies have shown considerable risk of birth defects if these drugs are used in specific weeks of early pregnancy, and this should be taken into consideration when planning therapy and control of women who may in the future become pregnant. Early pregnancy is a period of major focus in GD, where pregnancy should be diagnosed as soon as possible, and where important and instant change in therapy may be warranted. Such change may be an immediate stop of anti-thyroid drug therapy in patients with a low risk of rapid relapse of hyperthyroidism, or it may be an immediate shift from methimazole/carbimazole (with risk of severe birth defects) to propylthiouracil (with less risk), or maybe to other types of therapy where no risk of birth defects have been observed. In the second half of pregnancy, an important concern is that not only the mother with GD but also her foetus should have normal thyroid function.

2016 American Thyroid Association Guidelines for Diagnosis and Management of Hyperthyroidism and Other Causes of Thyrotoxicosis

BACKGROUND

Thyrotoxicosis has multiple etiologies, manifestations, and potential therapies. Appropriate treatment requires an accurate diagnosis and is influenced by coexisting medical conditions and patient preference. This document describes evidence-based clinical guidelines for the management of thyrotoxicosis that would be useful to generalist and subspecialty physicians and others providing care for patients with this condition.

METHODS

The American Thyroid Association (ATA) previously cosponsored guidelines for the management of thyrotoxicosis that were published in 2011. Considerable new literature has been published since then, and the ATA felt updated evidence-based guidelines were needed. The association assembled a task force of expert clinicians who authored this report. They examined relevant literature using a systematic PubMed search supplemented with additional published materials. An evidence-based medicine approach that incorporated the knowledge and experience of the panel was used to update the 2011 text and recommendations. The strength of the recommendations and the quality of evidence supporting them were rated according to the approach recommended by the Grading of Recommendations, Assessment, Development, and Evaluation Group.

RESULTS

Clinical topics addressed include the initial evaluation and management of thyrotoxicosis; management of Graves' hyperthyroidism using radioactive iodine, antithyroid drugs, or surgery; management of toxic multinodular goiter or toxic adenoma using radioactive iodine or surgery; Graves' disease in children, adolescents, or pregnant patients; subclinical hyperthyroidism; hyperthyroidism in patients with Graves' orbitopathy; and management of other miscellaneous causes of thyrotoxicosis. New paradigms since publication of the 2011 guidelines are presented for the evaluation of the etiology of thyrotoxicosis, the management of Graves' hyperthyroidism with antithyroid drugs, the management of pregnant hyperthyroid patients, and the preparation of patients for thyroid surgery. The sections on less common causes of thyrotoxicosis have been expanded.

CONCLUSIONS

One hundred twenty-four evidence-based recommendations were developed to aid in the care of patients with thyrotoxicosis and to share what the task force believes is current, rational, and optimal medical practice.

Recent Advances in Autoimmune Thyroid Diseases

Autoimmune thyroid disease (AITD) includes hyperthyroid Graves disease, hypothyroid autoimmune thyroiditis, and subtle subclinical thyroid dysfunctions. AITD is caused by interactions between genetic and environmental predisposing factors and results in autoimmune deterioration. Data on polymorphisms in the AITD susceptibility genes, related environmental factors, and dysregulation of autoimmune processes have accumulated over time. Over the last decade, there has been progress in the clinical field of AITD with respect to the available diagnostic and therapeutic methods as well as clinical consensus. The updated clinical guidelines allow practitioners to identify the most reasonable and current approaches for proper management. In this review, we focus on recent advances in understanding the genetic and environmental pathogenic mechanisms underlying AITD and introduce the updated set of clinical guidelines for AITD management. We also discuss other aspects of the disease such as management of subclinical thyroid dysfunction, use of levothyroxine plus levotriiodothyronine in the treatment of autoimmune hypothyroidism, risk assessment of long-standing antithyroid drug therapy in recurrent Graves' hyperthyroidism, and future research needs.

Hyperthyroidism

Hyperthyroidism is characterised by increased thyroid hormone synthesis and secretion from the thyroid gland, whereas thyrotoxicosis refers to the clinical syndrome of excess circulating thyroid hormones, irrespective of the source. The most common cause of hyperthyroidism is Graves' disease, followed by toxic nodular goitre. Other important causes of thyrotoxicosis include thyroiditis, iodine-induced and drug-induced thyroid dysfunction, and factitious ingestion of excess thyroid hormones. Treatment options for Graves' disease include antithyroid drugs, radioactive iodine therapy, and surgery, whereas antithyroid drugs are not generally used long term in toxic nodular goitre, because of the high relapse rate of thyrotoxicosis after discontinuation. β blockers are used in symptomatic thyrotoxicosis, and might be the only treatment needed for thyrotoxicosis not caused by excessive production and release of the thyroid hormones. Thyroid storm and hyperthyroidism in pregnancy and during the post-partum period are special circumstances that need careful assessment and treatment.

The 2015 European Thyroid Association Guidelines on Diagnosis and Treatment of Endogenous Subclinical Hyperthyroidism

Endogenous subclinical hyperthyroidism (SHyper) is caused by Graves' disease, autonomously functioning thyroid nodules and multinodular goitre. Its diagnosis is based on a persistently subnormal serum thyroid-stimulating hormone (TSH) level with free thyroid hormone levels within their respective reference intervals. In 2014 the European Thyroid Association Executive Committee, given the controversies regarding the treatment of Endo SHyper, formed a task force to develop clinical practice guidelines based on the principles of evidence-based medicine. The task force recognized that recent meta-analyses, including those based on large prospective cohort studies, indicate that SHyper is associated with increased risk of coronary heart disease mortality, incident atrial fibrillation, heart failure, fractures and excess mortality in patients with serum TSH levels <0.1 mIU/l (grade 2 SHyper). Therefore, despite the absence of randomized prospective trials, there is evidence that treatment is indicated in patients older than 65 years with grade 2 SHyper to potentially avoid these serious cardiovascular events, fractures and the risk of progression to overt hyperthyroidism. Treatment could be considered in patients older than 65 years with TSH levels 0.1-0.39 mIU/l (grade 1 SHyper) because of their increased risk of atrial fibrillation, and might also be reasonable in younger (<65 years) symptomatic patients with grade 2 SHyper because of the risk of progression, especially in the presence of symptoms and/or underlying risk factors or co-morbidity. Finally, the task force concluded that there are no data to support treating SHyper in younger asymptomatic patients with grade 1 SHyper. These patients should be followed without treatment due to the low risk of progression to overt hyperthyroidism and the weaker evidence for adverse health outcomes.

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.

A second course of antithyroid drug therapy for recurrent Graves' disease: an experience in endocrine practice

OBJECTIVE

There are scarce reports regarding the prognosis of a second course of antithyroid drug (ATD) therapy on recurrent Graves' disease (GD). The aim of this study was to assess the long-term remission rate after a second ATD therapy and verify significant clinical predictors of a remission.

DESIGN

A prospective randomized clinical trial with long-term follow-up was conducted to evaluate the effects of a second course of ATD therapy.

METHODS

A total of 128 recurrent GD patients who had finished a first regular ATD therapy were enrolled in this study, and prescribed methimazole (MMI) treatment with titration regimen. The patients were randomly assigned to two groups when the drug doses were reduced to 2.5 mg daily (qd). Group 1 was discontinued with 2.5 mg qd after about 5 months. Group 2 was continuously reduced to 2.5 mg every other day (qod) after 5 months and then discontinued with 2.5 mg qod after about a further 5 months. The patients were followed for 48 months after drug withdrawal.

RESULTS

Of the total number of patients, 97 cases (75.78%) achieved permanent remission at the end of follow-up, with the recurrence of 31 cases (24.22%). The remission rate of group 2 (84.62%) was significantly higher than that of group 1 (66.67%) (P=0.024). Cox regression showed that the hazard ratio for recurrence decreased under a high or high normal TSH level at drug withdrawal.

CONCLUSION

A second course of ATD therapy can bring about a satisfying long-term remission on recurrent GD. The drug dose of 2.5 mg qod and a high or high normal TSH level at drug withdrawal may increase the likelihood of permanent remission.