Can we predict relapse in Graves' disease? Results from a systematic review and meta-analysis

Graves disease: latest understanding of pathogenesis and treatment options

Graves disease is the most common cause of hyperthyroidism in iodine-sufficient areas. The main responsible mechanism is related to autoantibodies that bind and activate the thyrotropin receptor (TSHR). Although Graves hyperthyroidism is relatively common, no causal treatment options are available. Established treatment modalities are antithyroid drugs, which reduce thyroid hormone synthesis, radioactive iodine and surgery. However, emerging drugs that target the main autoantigen (monoclonal antibodies, small molecules, peptides) or block the immune pathway have been recently tested in clinical trials. Graves disease can involve the thyroid exclusively or it can be associated with extrathyroidal manifestations, among which Graves orbitopathy is the most common. The presence of Graves orbitopathy can change the management of the disease. An established treatment for moderate-to-severe Graves orbitopathy is intravenous glucocorticoids. However, recent advances in understanding the pathogenesis of Graves orbitopathy have allowed the development of new target-based therapies by blocking pro-inflammatory cytokine receptors, lymphocytic infiltration or the insulin-like growth factor 1 receptor (IGF1R), with several clinical trials providing promising results. This article reviews the new discoveries in the pathogenesis of Graves hyperthyroidism and Graves orbitopathy that offer several important tools in disease management.

Graves-PCD: protocol for a randomised, dose-finding, adaptive trial of the plasma cell-depleting agent daratumumab in severe Graves' disease

INTRODUCTION

Severe Graves' disease is a life-changing condition with poor outcomes from currently available treatments. It is caused by directly pathogenic thyroid-stimulating hormone receptor-stimulating antibodies (TRAb), which are secreted from plasma cells. The human anti-CD38 monoclonal antibody daratumumab was developed to target plasma cells which express high levels of CD38, and is currently licensed for treatment of the plasma cell malignancy, myeloma. However, it can also deplete benign plasma cells with the potential to reduce TRAb and alter the natural history of severe Graves' disease. This study aims to establish proof of concept that daratumumab has efficacy in patients with severe Graves' disease and will provide important data to inform a choice of dosing regimen for subsequent trials.

METHODS AND ANALYSIS

The Graves-PCD trial aims to determine if daratumumab modulates the humoral immune response in patients with severe Graves' disease, and if so, over what time period, and to find an optimal dose. It is a single-blinded, randomised, dose-finding, adaptive trial using four different doses of daratumumab or placebo in 30 adult patients. Part 1 of the trial is dose-finding and, following an interim analysis, in part 2, the remaining patients will be randomised between the chosen dose(s) from the interim analysis or placebo. The primary outcome is the percentage change in serum TRAb from baseline to 12 weeks.

ETHICS AND DISSEMINATION

The trial received a favourable ethical opinion from London-Hampstead Research Ethics Committee (reference 21/LO/0449). The results of this trial will be disseminated at international meetings, in the peer-reviewed literature and through partner patient group newsletters and presentations at patient education events.

TRIAL REGISTRATION NUMBER

ISRCTN81162400.

Association Between HLA-DRB1 Alleles and Graves' Disease in Asian Populations: A Meta-Analysis

Graves' disease (GD) is an autoimmune disease that primarily affects the thyroid gland. It is the most common cause of hyperthyroidism. Genetic studies have shown that human leukocyte antigen (HLA) plays an important role in the development of GD. In this article, we performed a meta-analysis determined to evaluate the relationship between HLA-DRB1 alleles and GD. This meta-analysis included 9 studies (3582 cases in the case group and 23070 cases in the control group) and 27 alleles was performed. The combined results showed that, compared with the control group, GD patients have a significant increase in the frequency of DRB1*1403 (OR=2.50, 95% CI=1.78-3.51, pc<0.0001) and have a significant decrease in frequencies of DRB1* 0101 (OR=0.45, 95% CI=0.34-0.59, pc<0.0001) and DRB1*0701 (OR=0.44, 95% CI=0.35-0.55, pc<0.0001). The meta-analysis indicated that, in Asian populations, DRB1*1403 is a risk allele for GD, and DRB1*0101 and DRB1*0701 are protective against the occurrence of GD. We surprisingly discovered that the susceptibility alleles for GD in Asian populations are completely different from Caucasians and the protective alleles for GD in Asians are quite similar to those of Caucasians. The results of our study may provide new opportunities for gene-targeted therapy for GD in Asian populations.

Risk of recurrence at the time of withdrawal of short- or long-term methimazole therapy in patients with Graves' hyperthyroidism: a randomized trial and a risk-scoring model

PURPOSE

In Graves' disease, administration of low-dose methimazole for more than 60 months induces higher remission rates compared with the conventional duration of 12-18 months. However, the risk of recurrence and its predictors beyond 48 months of drug withdrawal are not known. The aims of this study were to determine the risk of recurrence during 84 months after withdrawal of short- or long-term methimazole therapy and a risk stratification for recurrence of hyperthyroidism.

METHODS

A total of 258 patients were treated with methimazole for a median of 18 months and randomized to discontinuation of the drug(conventional short-term group; n = 128) or continuation of the treatment up to 60-120 months(long-term group; n = 130). Patients were followed for 84 months after methimazole withdrawal. Cox proportional hazards modeling was performed to identify factors associated with relapse and develop a risk-scoring model at the time of discontinuing the treatment.

RESULTS

Hyperthyroidism recurred in 67 of 120(56%) of conventionally-treated patients versus 20 of 118(17%) of those who received long-term methimazole treatment, p < 0.001. Age, sex, goiter grade, triiodothyronine, thyrotropin, and thyrotropin receptor antibodies were significant predictors of recurrence in both "conventional" and "long-term" groups but free thyroxine just in the "long-term" group. The risk-scoring model had a good discrimination power (optimism corrected c-index = 0.78,95%CI = 0.73-0.82) with a range of 0-14 and sensitivity of 86% and specificity of 62% at the risk-score of eight.

CONCLUSION

A relapse-free state was achieved in 83% of patients with Graves' hyperthyroidism 84 months after cessation of long-term methimazole treatment which could be predicted by some significant predictors in a simple risk-scoring system.

Lipid Profile Evolution in Graves' Disease Treated with Titration Regimen of Anti-Thyroid Drugs Versus Block and Replace Regimen

The aim was to compare the lipid profile of patients with GD treated with anti-thyroid drugs (ATDs) using a titration regimen versus a block and replace regimen. This is an 18-month prospective observational study. In this study were included 149 medically treated GD patients, aged+>+18 years. Pregnant women and patients treated with radioactive iodine therapy or partial/total thyroidectomy were excluded. Patients were divided into 2 subgroups: titration (A) and block and replace (B) therapy, according to the ATD regimen used. Thyroid and metabolic profile was measured at baseline and at least one visit during medical treatment. The whole group included 122 (81.87%) females (F) and 27 (18.12%) males (M), ratio F:M=4.5:1. As expected, at the time of diagnosis, thyrotoxic patients were with normal lipid profile. During medical treatment, in patients who achieved euthyroidism, the cholesterol levels increased as follows: in subgroup A: by 52.9 mg/dl (95% CI: 26.4-79.3), p<0.001 for total cholesterol (T-C), by 33.3 mg/dl (95% CI: 10.3-56.3), p=0.007 for low-density lipoprotein cholesterol (LDL-C) and by 11.44 mg/dl (95% CI: 3.08-19.79), p=0.009 for high-density lipoprotein cholesterol (HDL-C); in subgroup B T-C increased by 45.1 mg/dl (95% CI: 22.2-68), p<0.001 and for LDL-C by 33.57 mg/dl (95% CI: 12.72-54.42), p=0.003. No statistically significant increase in triglyceride levels was determined. Medical treatment of hyperthyroidism due to Graves' disease increased cholesterol levels regardless of the ATD regimen used.

Enhanced predictive validity of integrative models for refractory hyperthyroidism considering baseline and early therapy characteristics: a prospective cohort study

BACKGROUND

A subset of Graves' disease (GD) patients develops refractory hyperthyroidism, posing challenges in treatment decisions. The predictive value of baseline characteristics and early therapy indicators in identifying high risk individuals is an area worth exploration.

METHODS

A prospective cohort study (2018-2022) involved 597 newly diagnosed adult GD patients undergoing methimazole (MMI) treatment. Baseline characteristics and 3-month therapy parameters were utilized to develop predictive models for refractory GD, considering antithyroid drug (ATD) dosage regimens.

RESULTS

Among 346 patients analyzed, 49.7% developed ATD-refractory GD, marked by recurrence and sustained Thyrotropin Receptor Antibody (TRAb) positivity. Key baseline factors, including younger age, Graves' ophthalmopathy (GO), larger goiter size, and higher initial free triiodothyronine (fT3), free thyroxine (fT4), and TRAb levels, were all significantly associated with an increased risk of refractory GD, forming the baseline predictive model (Model A). Subsequent analysis based on MMI cumulative dosage at 3 months resulted in two subgroups: a high cumulative dosage group (average ≥ 20 mg/day) and a medium-low cumulative dosage group (average < 20 mg/day). Absolute values, percentage changes, and cumulative values of thyroid function and autoantibodies at 3 months were analyzed. Two combined predictive models, Model B (high cumulative dosage) and Model C (medium-low cumulative dosage), were developed based on stepwise regression and multivariate analysis, incorporating additional 3-month parameters beyond the baseline. In both groups, these combined models outperformed the baseline model in terms of discriminative ability (measured by AUC), concordance with actual outcomes (66.2% comprehensive improvement), and risk classification accuracy (especially for Class I and II patients with baseline predictive risk < 71%). The reliability of the above models was confirmed through additional analysis using random forests. This study also explored ATD dosage regimens, revealing differences in refractory outcomes between predicted risk groups. However, adjusting MMI dosage after early risk assessment did not conclusively improve the prognosis of refractory GD.

CONCLUSION

Integrating baseline and early therapy characteristics enhances the predictive capability for refractory GD outcomes. The study provides valuable insights into refining risk assessment and guiding personalized treatment decisions for GD patients.

Outcomes of Patients With Graves Disease 25 Years After Initiating Antithyroid Drug Therapy

CONTEXT

Graves disease (GD) is a leading cause of hyperthyroidism. Detailed investigations and predictors of long-term outcomes are missing.

OBJECTIVE

This work aimed to investigate the outcomes in GD 25 years after initiating antithyroid drug treatment, including disease course, clinical and biochemical predictors of relapse, and quality of life.

METHODS

A retrospective follow-up was conducted of GD patients that participated in a randomized trial from 1997 to 2001. Demographic and clinical data were obtained from medical records and questionnaires. Biobank samples were analyzed for inflammatory biomarkers and compared with age- and sex-matched healthy individuals.

RESULTS

We included 83% (182/218) of the patients from the original study. At the end of follow-up, normal thyroid function was achieved in 34%. The remaining had either active disease (1%), spontaneous hypothyroidism (13%), or had undergone ablative treatment with radioiodine (40%) or thyroidectomy (13%). Age younger than or equal to 40 years, thyroid eye disease (TED), smoking, and elevated levels of interleukin 6 and tumor necrosis factor receptor superfamily member 9 (TNFRS9) increased the risk of relapsing disease (odds ratio 3.22; 2.26; 2.21; 1.99; 2.36). At the end of treatment, CD40 was lower in patients who maintained normal thyroid function (P = .04). At the end of follow-up, 47% had one or more autoimmune diseases, including vitamin B12 deficiency (26%) and rheumatoid arthritis (5%). GD patients who developed hypothyroidism had reduced quality of life.

CONCLUSION

Careful lifelong monitoring is indicated to detect recurrence, hypothyroidism, and other autoimmune diseases. Long-term ATD treatment emerges as a beneficial first-line treatment option, especially in patients with young age at onset or presence of TED.

Effect of Vitamin D Supplementation on Graves' Disease: The DAGMAR Trial

Objective: Treatment options in Graves' disease (GD) are limited and do not target the underlying autoimmunity, and relapse rates following a course of antithyroid drug (ATD) reach 50%. Previous research has shown promising results for a role of vitamin D in GD. We aimed to investigate whether vitamin D reduces failure to enter and sustain remission in patients with GD treated with ATD. Design: A multicenter, double-blinded, randomized placebo-controlled trial comparing vitamin D 70 mcg once daily (2800 IU) or placebo. The intervention was given first as add-on to ATD treatment, maximally 24 months, and then for 12 months after ATD cessation. Inclusion period was from 2015 to 2017 and study completion by December 2020. Patients included were adults with a first-time diagnosis of GD treated with ATD. Exclusion criteria included pregnancy and glucocorticoid treatment. The primary endpoint was failure to enter and sustain remission defined as relapse of hyperthyroidism within 12 months after ATD cessation, inability to stop ATD within 24 months, or radioiodine treatment or thyroidectomy. Two hundred seventy-eight patients were included in the study, and 4 patients withdrew consent. No adverse effects were found. Results: Participants were aged 44 ± 14 years at enrollment and 79% were female. The risk of failure to enter and sustain remission was 42% [95% confidence interval (CI) 33-50%] in the vitamin D group and 32% [CI 24-40%] in the placebo group corresponding to a relative risk of 1.30 [CI 0.95-1.78]. Conclusions: Vitamin D supplementation did not improve the treatment of GD in patients with normal or insufficient vitamin D status. Thus, supplementation with high-dose vitamin D cannot be recommended for GD. Study registration: ClinicalTrials.gov NCT02384668.

New-onset and relapsed Graves' disease following COVID-19 vaccination: a comprehensive review of reported cases

Global Coronavir us disease 2019 (COVID-19) vaccination efforts are being intensified to combat the pandemic. As the frequency of immunization against COVID-19 has increased, some adverse effects related to vaccination have emerged. Within this context, this article reviewed 62 Graves' disease (GD) cases following COVID-19 vaccination, to probe the potential association between the vaccination and the onset of GD. A comprehensive search of the PubMed, Web of Science, and Scopus databases was conducted to collect GD cases following COVID-19 vaccination up to June 7, 2023. Among the 62 GD cases included in this review, there were 33 (53.2%) new-onset GD and 10 (16.1%) relapsed GD patients following mRNA vaccination, 14 (22.6%) new-onset GD and 4 (6.5%) relapsed GD patients following viral vector vaccination, and 1 (1.6%) relapsed GD patients following inactivated vaccination. Median durations to symptoms onset for new-onset and relapsed GD were 12 (range: 1-60) and 21 (range: 5-30) days following mRNA vaccination, while 7 (range: 1-28) and 14 (range: 10-14) days following viral vector vaccination, respectively. While the definitive pathogenesis of GD following COVID-19 vaccination remains unclear, it might be associated with cross-immune responses triggered by molecular mimicry, and an adjuvant-induced autoimmune/inflammatory syndrome. However, due to the limited number of observed GD cases following COVID-19 vaccination and the lack of systematic experimental studies, a causal relationship between COVID-19 vaccination and the onset of GD has not been definitively confirmed. It should be highlighted that most of GD patients following COVID-19 vaccination experienced positive outcomes after treatment. In the broader context of ending the COVID-19 pandemic and reducing mortality rates, the benefits of COVID-19 vaccination significantly outweigh mild risks such as treatable GD. Adherence to the COVID-19 vaccination schedule is therefore imperative in effectively managing the pandemic.

The Clinical Implications of Anti-thyroid Peroxidase Antibodies in Graves’ Disease in Basrah

Background Graves' disease (GD) is an autoimmune disease, with thyrotropin receptor antibodies (TRAbs) being the most important cause in the pathogenesis. The aim of this study is to assess the clinical significance of anti-TPO Abs in GD. Methods A retrospective study was conducted at the Faiha specialized Diabetes, Endocrine, and Metabolism Center (FDEMC) in Basrah during the period between December 2021 and December 2022. A total of 141 patients with GD were involved in this study, and of them, 97 (68.8%) were women. They were divided into two groups: patients with positive and negative anti-TPO Abs groups. Results Positive anti-TPO Abs were seen in 83 patients (58.9%) with GD. Pretreatment-free thyroxine level (ng/dL) was higher in the anti-TPO Abs positive GD patients than in those with negative antibodies (3.7±0.2 versus 3.0±0.2 with a p=0.021). Similarly, higher TRAb titers (IU/ml) at baseline were also seen in patients with positive anti-TPO Abs (9.8±0.7 versus 6.8±0.8) with a p=0.008. Giraffe appearance on thyroid ultrasound was more common in the group with positive anti-TPO Abs as compared to patients with negative anti-TPO Abs: 20 (87.0%) versus 3 (13.0%) with a p=0.005. A higher anti-TPO Abs titer (IU/mL) was associated with a baseline TRAb level of more than 6.4 IU/mL, and giraffe appearance on thyroid ultrasound (206.5±20.0 p-value<0.0001 and 228.0±35.3 p value=0.007, respectively). Conclusion A positive anti-TPO Abs in GD is associated with a high TRAb titer and free T4 level at baseline, as well as a giraffe appearance on thyroid ultrasound.

Thyroid autoantibodies

Thyroid-stimulating hormone (TSH) receptor antibody (TSH-R-Ab or TRAb) testing plays a pivotal role in arriving at the aetiological diagnosis in patients with thyrotoxicosis. A positive test establishes the diagnosis of Graves' disease (GD) while a negative result in conjunction with imaging studies supports other possible aetiologies. In patients with GD, TRAb levels at diagnosis and at the time of withdrawal of antithyroid drugs can identify patients who are unlikely to achieve remission and guide clinical management decisions. We provide an algorithm that incorporates TRAb in the decision-making process for the management of thyrotoxicosis. The utility of TRAb in predicting the risk of fetal and neonatal thyroid dysfunction is established and widely accepted in guidelines. TRAb may also help in the diagnosis of Graves' orbitopathy, especially in euthyroid or hypothyroid patients and its role in guiding its management is evolving as a useful adjunct to the clinical parameters used in making therapeutic decisions.Anti-thyroid peroxidase antibodies (TPOAb) and anti-thyroglobulin antibodies (TgAb) indicate thyroid autoimmunity. The most common use of TPOAb is to identify patients at a higher risk of progression to treatment-requiring hypothyroidism. They also aid the diagnosis of immune thyroiditis and Hashimoto's encephalopathy. Thyroglobulin measurement is used to help guide differentiated thyroid cancer treatment. TgAb is used as an accompanying test with thyroglobulin measurement as its presence can interfere with the thyroglobulin assay. A negative TgAb result reduces the likelihood of, but does not exclude, interference with thyroglobulin assay.

Incidence and treatment outcomes of Graves' disease in Thailand: a single-center retrospective observational study

BACKGROUND

Treatment patterns and outcomes of Graves' disease (GD) are variable around the world. However, studies on treatment outcomes of GD from the Asian populations are limited. We aimed to evaluate treatment outcomes of GD in Thailand.

METHODS

Patients with new diagnoses of GD in a single center between 2014-2018 were retrospectively reviewed. The diagnosis of GD was based on clinical features, which included diffuse goiter, Graves' orbitopathy (GO), pretibial myxedema and acropachy.

RESULTS

The age-adjusted incidence of GD was 26.57 per 100,000 per year. The study included 355 patients aged 15 years or above with a follow-up period of at least 24 months. Antithyroid drug (ATD) was the most popular first-line treatment modality with 98.7% patients receiving the treatment, followed by radioactive iodine (RAI) treatment in 1.3% patients. The most effective treatment modality was surgery with a remission rate of 100%. ATD had a lowest remission rate of 23.8%. Multivariable Cox regression analysis showed GO (HR 1.76, 95% CI 1.08-2.88) and initial TSH < 0.01 uIU/ml (HR 1.61, 95% CI 1.14-2.28) were significant factors associated with an increased treatment failure rate.

CONCLUSION

Treatment failure with ATD in patients with GD was frequent in this population. The diagnosis of GD based solely on clinical features may explain the high treatment failure rate in this study. More definitive treatment could be used to prevent relapse and complications of the disease.

The relationship between atherosclerotic disease and relapse during ATD treatment

Background

Clinical relapse is a potential risk for traditional antithyroid drug (ATD) treatment in hyperthyroid patients. Evidence suggests that atherosclerotic disease is closely associated with hyperthyroidism, while the relationship between atherosclerosis and relapse remains unclear.

Methods

Two hundred and twenty-five patients with GD who underwent ATD as their first treatment were studied; 88 and 137 patients were categorized as drug reduction relapse and drug reduction remission, respectively. Logistic regression was used to analyze risk factors of drug reduction relapse in patients with GD.

Results

During a median of 48 months followed up 88 patients who relapsed. According to multivariate analyses, atherosclerosis related diseases, FT4, goiter, and anxiety rating scores are independent risk factors for drug reduction. According to K-M survival analysis, patients with atherosclerosis related diseases, FT4 &gt; 18.82 pmol/L, anxiety rating scores &gt; 23, and gradation of goiter ≥ Grade II had a higher risk of relapse than those with lower levels. ROC analysis shown atherosclerosis related diseases significantly improved the predictive accuracy of relapse.

Conclusions

Atherosclerotic disease is closely related to the relapse of hyperthyroidism, ATD treatment in hyperthyroid patients with atherosclerosis should be given more attention.

High levels of thyroid hormones promote recurrence of Graves' disease via overexpression of B-cell-activating factor

Background

Elevated thyroid hormone (TH) levels have been suggested to be associated with the pathological progression of Graves' disease (GD). However, direct evidence from clinical studies remains unclear.

Methods

Peripheral blood samples were collected from patients with or without the recurrence of Graves' hyperthyroidism (GH) and healthy donors. Thyroid tissue samples were obtained from patients with benign thyroid nodules. To assess the differentiation of autoreactive B cells, the expression of B‐cell‐activating factor (BAFF) and the proportion of CD11c+/–IgG+/− subsets of B cells stimulated by high levels of triiodothyronine (T3) in vivo and in vitro were examined by ELISA, flow cytometry, western blotting, and qRT‐PCR.

Results

Serum BAFF levels in patients with GD were significantly and positively correlated with FT3, FT4, and TRAb levels. Furthermore, the ratio of abnormally differentiated CD11c+ autoreactive B cells positively correlated with BAFF and TRAb. High levels of triiodothyronine (T3) induced BAFF overexpression in thyroid follicular cells and mononuclear cells of the normal thyroid in vitro, thereby promoting the differentiation of CD11c+IgG+ autoreactive secretory B cells (ASCs). However, the precise knockdown of BAFF expression significantly inhibited the abnormal differentiation of ASCs.

Conclusion

The pathological progression of GD was prolonged and exacerbated by autoimmune positive feedback modulation caused by high TH levels. BAFF could be considered a potential target for localized thyroid immunosuppressive treatment of Graves' hyperthyroidism recurrence.

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 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.

Relapsed and newly diagnosed Graves’ disease due to immunization against COVID-19: A case series and review of the literature

In addition to genetic factors, environmental factors such as viruses are thought to be triggers in the development of autoimmune thyroid diseases (AITD) such as Graves' disease (GD). In this context, AITD cases that may be associated with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection or immunization have begun to be reported in increasing numbers. Although it is not clear by which pathogenetic mechanisms immunization against coronavirus disease 2019 (COVID-19) triggers the development of AITD, both the potential effect of the adjuvants in the vaccines and the cross-reactivity that can be generated by the molecular similarity of viral particles with mammalian proteins seem to be possible mechanisms. In this article, 7 GD patients consisting of relapsed and newly diagnosed cases following the COVID-19 vaccination were presented. Of these 7 cases, 5 (71.4%) were female, and the median age of the patients was 47 years (range, 31–53). One of the patients was associated with the inactivated COVID-19 vaccine, while the others were associated with the mRNA COVID-19 vaccine. The median post-vaccination symptom onset was 7 days (range, 4–30). Three of the patients had a history of GD and one had a history of Hashimoto's thyroiditis. Rapidly developing Graves' ophthalmopathy was detected in one patient. These cases are cautionary that GD and its extrathyroidal manifestations may develop in a short period after COVID-19 vaccination. When considered together with the literature review, the history of AITD in approximately half of the patients suggests that more attention should be paid to these patients in the post-vaccination period. Nevertheless, multicenter, prospective studies are needed to better understand this possible causal relationship.

Thyroid-Stimulatory Antibody as a Predictive Factor for Graves’ Disease Relapse

Introduction: Thyroid-stimulatory antibody (TSAb) assays have been recently optimized, potentially allowing to determine thyrotropin receptor antibodies' (TRAbs) functionality in routine clinical practice. We aimed to determine TSAb's predictive role of relapse at antithyroid drug (ATD) withdrawal in Graves’ disease (GD).

Methods: Retrospective study of GD patients with stable normal thyroid function under low ATD doses that were proposed for withdrawal. Thyroid function tests and TRAb and TSAb levels were obtained at ATD suspension and every three to six months after that, for a minimum of 16 months. Clinical factors associated with GD relapse, such as age at diagnosis, sex, smoking status, thyroid volume, and presence of orbitopathy, were also evaluated.

Results: Thirty-five patients with GD were included for analysis, with a median follow-up period of 24 months, during which 14 patients (40%) relapsed. Relapse was more common in patients with positive TSAb than patients with negative TSAb at ATD withdrawal (79% vs. 33%, p=0.01). Relapse-free survival was shorter in TSAb-positive patients (p=0.01). There were no differences in relapse rates according to TRAb positivity at ATD withdrawal (42.9% vs. 36.4%, p=0.74). We also did not find any differences in relapse rate regarding age, sex, smoking status, thyroid volume, or presence of Graves’ orbitopathy. On multivariate analysis, only TSAb positivity at ATD withdrawal was independently associated with relapse (hazard ratio [HR] 6.63, 95% confidence interval [CI], 1.30-33.7, p=0.02).

Conclusion: At ATD withdrawal, TSAb-positive patients demonstrated a higher risk for GD relapse. Measuring TSAb before ATD suspension, instead of TRAbs, could become an important tool for the clinical management of these patients.

Does Age or Sex Relate to Severity or Treatment Prognosis in Graves' Disease?

Background: The prognosis of Graves' disease (GD) is reportedly related to sex, age, and genetic factors, although there is no consensus. The objective of this study was to investigate the relationship between severity and prognosis of GD and sex or age. Methods: Subjects were patients newly diagnosed with GD between January 2005 and June 2019, and medical records were retrospectively reviewed. Patients diagnosed between January 2009 and December 2010 and followed up for at least 12 months were enrolled. Patients were divided into nine age-stratified groups. Remission was defined as maintenance of a euthyroid state for more than one year after withdrawal of antithyroid drugs (ATDs). Results: Participants comprised 21,633 patients (3954 males, 17,679 females). Initial free triiodothyronine (fT3) and free thyroxine (fT4) levels significantly decreased with increasing age, including after sex stratification. fT4 was significantly higher in males than females aged 20-39 years. In 2191 patients treated with ATDs alone, median durations until remission were 37.7 and 30.6 months in males and females, respectively. Remission and recurrence were observed in 1391 patients (204 males, 1187 females) and 262 patients (37 males, 225 females), respectively. By Kaplan-Meier analyses, males required a significantly longer time to achieve remission than females (p < 0.0001), although there were no significant age-related differences (p = 0.08). Cox proportional hazard modeling showed a 41% higher hazard ratio (HR) for remission in females than males (adjusted HRs [aHR] confidence interval [CI] = 1.41 [1.21-1.64]), and each additional 10 years of age had a 14% lower rate of recurrence (age [per 10-year increase], aHR [CI] = 0.86 [0.78-0.94]); no significant relationship between recurrence rate and sex was identified. Conclusions: Severity of hyperthyroidism in GD was significantly higher in males in their 20s and 30s, declining with advancing age in both sexes. Females were more likely to achieve remission than males, and younger patients had a higher risk of recurrence, although recurrence was unrelated to sex.

Programmed Cell Death-Ligand 1 (PD-L1) gene Single Nucleotide Polymorphism in Graves' Disease and Hashimoto's Thyroiditis in Korean Patients

BACKGROUND

Programmed cell death-ligand 1 (PD-L1) has an important role in regulating immune reactions by binding to programmed death 1 (PD-1) on immune cells, which could prevent the exacerbation of autoimmune thyroid disease (AITD). The aim of this study was to evaluate the association of PD-L1 polymorphism with AITD, including Graves' disease (GD) and Hashimoto's thyroiditis (HT).

METHODS

A total of 189 GD patients, 234 HT patients, and 846 healthy age- and sex-matched controls were enrolled in this study. We analyzed PD-L1 single nucleotide polymorphism (SNP) (rs822339) and investigated the associations with clinical disease course and outcome.

RESULTS

Genotype frequency at the PD-L1 marker RS822339 in GD (P=0.219) and HT (P=0.764) patients did not differ from that among healthy controls. In patients with GD, the A/G or G/G genotype group demonstrated higher TBII titer (20.6±20.5 vs. 28.0± 25.8, P=0.044) and longer treatment duration (39.0±40.4 months vs. 62.4±65.0 months, P=0.003) compared to the A/A genotype group. Among patients in whom anti-thyroid peroxidase (TPO) antibody was measured after treatment of GD, post-treatment antiTPO positivity was higher in the A/G or G/G genotype group compared to the A/A genotype group (48.1% vs. 69.9%, P=0.045). Among patients with HT, there was no significant difference of anti-TPO antibody positivity (79.4% vs. 68.6%, P=0.121), anti-thyroglobulin antibody positivity (80.9% vs. 84.7%, P=0.661), or development to overt hypothyroidism (68.0% vs. 71.1%, P=0.632) between the A/A genotype group and the A/G or G/G genotype group.

CONCLUSION

The genotype frequency of PD-L1 (rs822339) is not different in patients with AITD compared with healthy controls. The intact PD-1/PD-L1 pathway in GD and HT might be important to maintain chronicity of AITD by protecting immune tolerance. However, the PD-L1 SNP could be associated with difficulty in achieving remission in patients with GD, which may be helpful to predict the possibility of longer treatment. Further studies are required to investigate the complex immune tolerance system in patients with AITD.

Comparison of three methods for determining anti-thyrotropin receptor antibodies (TRAb) for diagnosis of Graves' disease: a clinical validation

Objectives

Graves' disease is secondary to the presence of anti-thyrotropin receptor antibodies (TRAb), which stimulate thyroid hormones. TRab determination is crucial for etiological diagnosis. The objectives of this study were (i) to compare two methods for determining TRab by chemoluminiscence vs. standard TRACE-immunofluorescence; (ii) to determine the diagnostic validity of the three methods.

Methods

A retrospective study in 194 patients with a TRAb determination request. TRAb were determined by immunofluorescence (Kryptor, ThermoFisher) and chemiluminescence (Immulite, Siemens and Maglumi, Snibe). Clinical validation: medical records were reviewed and categorized according to thyroid function. Statistical analysis: Differences in quantitative variables were assessed by intraclass correlation coefficient, Bland-Altman plot, and mean differences (mD). Qualitative variables were dichotomized by cut-off points; Kappa coefficient was calculated. Correlations were evaluated by Pearson's coefficient and Passing-Bablok regression analysis. The diagnostic validity of the three methods was investigated.

Results

Kryptor-Immulite: mD: 1.2 (95%CI: -16 to >18). Passing-Bablok: Constant error (95%CI: -0.8349 to -0.5987). Proportional error (95%CI: 0.7862-1.0387). ICC: 0.86 (95%CI: 0.82-0.89). Kappa coefficient: 0.68 (95%CI 0.59-0.78). Kryptor-Maglumi: mD: -0.3 (95%CI: -12 to >12). Passing-Bablok: Constant error (95%CI: -0.7701 to >0.1621. Proportional error (95%CI: 0.8571 to 1.3179. ICC: 0.93 (95%CI: 0.89-0.97). Kappa coefficient: 0.53 (95%CI: 0.32-0.74). Diagnosis of Graves' disease was confirmed in 113 patients (Kryptorf showed better specificity and positive predictive value, whereas Immulite demonstrated better sensitivity and negative predictive value).

Conclusions

The three methods have a good diagnostic performance for Graves' disease, with superimposable results on Bland-Altman plot. Interchangeability was not confirmed on the regression and agreement analysis, with the presence of biases.

Practice patterns and outcomes in the management of Thai patients with Graves' disease

BACKGROUND

The treatment of hyperthyroid Graves' disease (GD) varies considerably among geographic areas. In this study, we aimed to evaluate practice patterns and treatment outcomes in Thai patients with hyperthyroid GD.

METHODS

A retrospective cohort study over 35 years (1985-2019) in patients with hyperthyroid GD was conducted. The trends of treatment options were compared periodically during the study period and the overall remission rate from each option was determined.

RESULTS

A total of 2736 hyperthyroid GD patients were treated and followed-up for at least 3 months over the study period (female 82.0%, mean age at diagnosis 36.3 ± 12.0 years, median duration of follow-up 74.5 months). Anti-thyroid drug (ATD) was the most commonly used treatment (78.0%), followed by RAI (21.0%), and surgery (1.0%). There was a significant downward trend for surgery, from 12.3% in the 1980s to only 0.2% in last phase of the study period. The preference for RAI therapy has also decreased in the last 5 years. Among ATD-treated patients, the remission rate was achieved only in 30.7 and 16.0% of all ATD-treated patients were eventually treated with RAI. Spontaneous hypothyroidism developed in 2.7% of the ATD-treated patients during a follow-up period. Almost all RAI-treated patients (97.1%) developed hypothyroidism.

CONCLUSIONS

Our present study highlighted the changing landscape of primary treatments for hyperthyroid GD toward ATD and the sharp downward trend in the surgical option. Even though ATD was associated with a low remission rate, it was preferred by many patients and physicians. The use of RAI as the primary treatment decreased in the last decade. However, RAI was a very effective treatment for Graves' hyperthyroidism but will inevitably induce hypothyroidism and a requirement for life-long replacement therapy.

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.

Serum T3 Level and Duration of Minimum Maintenance Dose Therapy Predict Relapse n Methimazole-Treated Graves Disease

Background

Methimazole (MMI) has been advocated as a preferred option for most Graves disease (GD) patients. However, long-term remission after a course of MMI treatment is achieved in only 20% to 40% of patients, depending on the duration of follow-up.

Objective

To evaluate clinical factors for predicting relapse of GD in Thai patients after MMI treatment.

Methods

A retrospective analysis was performed of newly diagnosed patients with GD who achieved remission of hyperthyroid GD after at least 12 months of MMI treatment. Long-term outcomes were assessed and predictive factors of early and late relapse were evaluated.

Results

A total of 443 patients with newly diagnosed GD who were treated with MMI for at least 12 months from 1985 to 2019, and were able to discontinue medication, were studied. The mean age at diagnosis was 37.0 ± 11.4 years and 81.7% were female. Of the 320 patients (72.2%) who achieved initial remission after MMI treatment for 23 months, 106 patients (33.1%) experienced late relapse during the mean follow-up duration of 9.7 years after MMI withdrawal. The remission rates decreased from 36.4% at the first year after stopping MMI to only 20.7% at 10 years. High initial serum triiodothyronine (T3) level and duration of minimum maintenance dose therapy (MMDT) of <6 months were associated with late disease relapse after remission.

Conclusion

The long-term remission rate of Graves hyperthyroidism was achieved in one-fifth of MMI-treated Thai patients. Predictive markers for late relapse included high initial serum T3 level and a duration of MMDT of <6 months.

Basedow's disease with associated features of Hashimoto's thyroiditis based on histopathological findings

BACKGROUND

Basedow's disease and Hashimoto's thyroiditis are autoimmune thyroid disorders and usually diagnosed with elevation of serum autoimmune antibodies. Thyrotropin receptor antibodies (TRAb) and/or thyroid-stimulating antibody (TSAb) are usually used for diagnosis of Basedow's disease, and thyroid peroxidase antibodies (TPOAb) and/or thyroglobulin antibodies (TgAb) are for diagnosis of Hashimoto's thyroiditis. However, it is difficult to diagnose a subject as Basedow's disease with associated features of Hashimoto's thyroiditis only with elevation of such autoimmune antibodies.

CASE PRESENTATION

A 44-year-old woman with 5-year history of Basedow's disease underwent a total thyroidectomy. She did not have a goiter. TRAb, TSAb, TPOAg and TgAb were all positive before a total thyroidectomy. In histopathological macroscopic examination, diffuse hyperplasia of the thyroid gland was observed. Furthermore, in histopathological microscopic examination, both characteristics of Basedow's disease and Hashimoto's thyroiditis were observed. After a total thyroidectomy, titers of all thyroid-associated autoimmune antibodies were markedly reduced.

CONCLUSION

Herein, we report a subject with Basedow's disease without a goiter whose TPOAb and TgAb were relatively high at the onset of Basedow's disease. In addition, interestingly, the histopathological findings of this subject showed direct signs of Basedow's disease and Hashimoto's thyroiditis in the same thyroid gland. Considering from such findings, she seemed to have Basedow's disease with associated features of Hashimoto's thyroiditis. In conclusion, we should bear in mind the possibility of Basedow's disease with associated features of Hashimoto's thyroiditis in subjects with Basedow's disease, particularly when TPOAb and TgAb as well as TRAb and TSAb are positive.

Prediction of Relapse After Antithyroid Drugs Withdrawal: A Narrative Review

Context: Antithyroid drugs (ATD) are the first-line treatment for Graves’ disease (GD); however, relapse following treatment is approximately 30% - 40% in the first year, and 50% - 60% in the long term. Identification of risk factors that predict relapse, after discontinuing ATD, plays an important role in guiding therapeutic options. Evidence Acquisition: PubMed was used to search for studies published in English between 1995 and 2019. The following search terms were used: Graves’ disease, antithyroid drugs, relapse, recurrence, and outcome. The reference lists from review articles were also included in the search in order to find older journals. Results: Factors associated with a high recurrence rate, as reported in most studies, were divided into phenotype and genotype predictors. Phenotype factors included large goiter size, persistence of high TSH receptor antibody (TRAb), severe hyperthyroidism, smoking, younger age, male sex, and prior history of recurrence. Genotype factors included human leukocyte antigen (HLA), CD40, CTLA-4, PTPN22, Tg, and TSHR genes. In a subgroup analysis by age, genetic factors were better predictors in the younger group, while clinical signs were more useful in the older group. The reliability of using individual baseline risk factors to predict subsequent relapse is poor; however, predictive scores calculated by grouping single risk factors might help to predict future outcomes. Conclusions: Longer normalization time of TRAb, the persistence of a palpable goiter, and harboring genetic risk factors in younger patients are associated with high recurrence rate of GD. Multi-marker prediction models have been proposed and validated to improve the predictive value of relapse after ATD withdrawal.

Therapeutic efficacy and limitations of potassium iodide for patients newly diagnosed with Graves' disease

The efficacy of potassium iodide (KI) for Graves' disease (GD) has been reported, although few clinical reports have examined the long-term efficacy of treatment. The objective of this study was to investigate the efficacy and limitations of KI treatment for GD. This study enrolled patients newly diagnosed with mild GD, defined as free thyroxine (FT4) <5.0 ng/dL, between July 2014 and June 2016. KI was started at a dose of 50 mg/day, and if FT4 values did not decrease after initiation of treatment, doses were increased to 100 mg/day. Patients for whom thyroid hormone levels could not be controlled with KI at 100 mg/day were regarded as non-responders. Of the 122 patients (13 males, 109 females) included in this study, 71 (58.2%) responded to KI therapy. The remaining 51 patients (41.8%) were non-responders. The median duration required to judge non-responsiveness was 5.9 months. Multiple logistic regression analysis performed on parameters measured at the initial visit indicated FT4 (odds ratio (OR) 2.19, 95% confidence interval (CI) 1.28-3.75; p = 0.0007) and male sex (OR 3.58, 95%CI 1.04-12.3; p = 0.04) were significantly associated with KI responsiveness. Receiver operating characteristic (ROC) curve analysis of the relationship between FT4 and KI responsiveness indicated an FT4 cut-off of 2.76 ng/dL was optimal for differentiating between responders and non-responders. KI therapy was effective and safe for about 60% of patients with mild GD.

Risk Factors for the Relapse of Graves' Disease Treated With Antithyroid Drugs: A Systematic Review and Meta-analysis

PURPOSE

Antithyroid drugs (ATDs) are the first-line treatment for Graves' disease (GD). A common problem with ATD treatment is the high relapse rate after drug withdrawal. The goal of this study was to analyze the influencing factors for the relapse of GD patients treated with ATD by using a systematic review and meta-analysis, provide some predictive indexes for the susceptibility of GD recurrence, and then further explore some useful methods to decrease the GD relapse rate after ATD treatment.

METHODS

Articles published in PubMed, EMBASE, The Cochrane Library, China National Knowledge Infrastructure, Wan Fang, and Chinese Biomedical Literature databases before January 2019 were collected. Patients newly diagnosed with GD, who were aged >16 years, were treated with ATD. Follow-up was then conducted for at least 12 months after ATD withdrawal. Only prospective or retrospective studies were eligible. The primary end point was the recurrence of GD during follow-up. All the data from the trials were analyzed via meta-analysis and meta-regression. p values < 0.05 were considered statistically significant, and statistical heterogeneity was assessed by using I² statistics.

FINDINGS

A total of 20 studies and 3242 patients were involved in this meta-analysis, with 1681 patients relapsed (incidence rate, 51.9%) during the follow-up time. Analysis of risk factors suggested that younger age (weighted raw mean difference [RMD], -3.51; 95% CI, -5.74 to -1.29), larger thyroid volume (RMD, 4.38; 95% CI, 1.68 to 7.08), bigger goiter size (1.94% risk; 95% CI, 0.43 to 3.46), higher free triiodothyronine level (RMD, 5.09; 95% CI, 4.42 to 5.77), and higher free thyroxine level (RMD, 4.21; 95% CI, 0.54 to 7.89) were associated with the higher relapse rate of GD. The block-replace ATD regimen (a fixed high dose of an ATD with levothyroxine supplementation to maintain euthyroidism) (risk ratio, 0.64; 95% CI, 0.52 to 0.78) exhibits a lower relapse rate than the titration regimen (an ATD used alone and dose adjusted according to thyroid function tests).

IMPLICATIONS

This analysis revealed that certain risk factors were associated with GD relapses such as younger age, larger goiter size or thyroid volume, and the higher free triiodothyronine or free thyroxine level in the diagnosing phase of GD. For patients with these clinical characteristics, early definitive treatment with radioactive iodine or surgery should be offered to those who are unlikely to achieve remission with ATDs only. In addition, more prospective cohort studies with different ATD regimens would help to determine the optimum ATD treatment for patients with GD. PROSPERO identifier: CRD 42019146825.

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.

A novel third-generation TSH receptor antibody (TRAb) enzyme-linked immunosorbent assay based on a murine monoclonal TSH receptor-binding antibody

TSH receptor (TSHR) autoantibody (TRAb) is the serological hallmark of Graves' disease (GD). Third-generation enzyme-linked immunosorbent assays (ELISAs) using monoclonal TRAbs instead of TSH have been found useful for TRAb analysis recently. For the first time, a mouse monoclonal antibody (mAb) against TSHR was analyzed for TRAb detection and compared with human mAb M22 and TSH by the same competitive binding assay technique. A mouse monoclonal antibody (T7) binding to the TSH receptor and inhibiting TSH binding was generated and used for TRAb analysis in a third-generation ELISA. Obtained TRAb levels were compared with a second-generation TRAb assay employing bovine TSH and a third-generation assay with human mAb M22 as TSHR-binding reagents by investigating 89 patients with GD, 56 with Hashimoto's thyroiditis (HT), 73 with non-autoimmune thyroid diseases, 17 with rheumatoid arthritis, and 100 healthy subjects. The T7-based TRAb ELISA did not reveal a significantly different assay performance (area under the curve [AUC]) in contrast to the TSH and M22-based TRAb ELISAs by receiver operating characteristic (ROC) curve analysis (AUC-T7 0.967, AUC-TSH 0.972, AUC-M22 0.958, p > 0.05, respectively). After adjustment of cutoffs by ROC, all three TRAb ELISAs demonstrated sensitivities and specificities above 89.9% and 96.0%, respectively. Both third-generation TRAb ELISAs showed a tendency for a higher prevalence of TRAb positives in HT in contrast to the second-generation ELISA. Mouse mAbs against the TSHR may be used for the reliable detection of TRAb by third-generation TRAb ELISA. The earlier reported higher sensitivity of third-generation TRAb ELISA in GD needs to be considered in the context of a slightly lower specificity regarding HT.

The long-term follow-up of patients with thionamide-treated Graves' hyperthyroidism

Since there have been few reports on the long-term prognosis of Graves' hyperthyroidism, the prognosis of 549 Graves' hyperthyroidism patients initially treated with thionamide and followed for >8 (range: 8.6-36.4) years was studied, evaluating the change in the TSH binding inhibitor immunoglobulin activity (TBII). The distribution of the time required for the first disappearance of TBII was normal after logarithmic conversion, and the mean ± 2 SD was 1.5 (0.3-8.1) years. TBII became negative once within 5 years in 78.9% of patients. However, TBII re-elevation was observed in 47.8% of this group (fluctuating type). Remission was observed in 88.9% of the non-fluctuating type (smooth remission) and 37.2% of the fluctuating type patients. TBII remained positive for >5 years in 21.1% (smoldering type) of patients, with remission observed in only 19.8% of patients. Final remission was observed in 301 (54.8%) patients; the median time to remission was 6.8 (interquartile range: 4.0-10.9) years. A longer time until normalization of TBII and higher final thyroid weight were associated with a poor prognosis. Spontaneous hypothyroidism was observed in 6.0% of patients, independent of the TBII change. Our findings suggest that remission of Graves' hyperthyroidism mostly occurred after 4-11 years treatment. While predicting the prognosis before therapy was difficult, the clinical course may suggest a better prognosis if TBII disappears within five years without TBII fluctuation or enlargement of the goiter. Patients may safely wait more than five years to undergo ablative therapy if they hope to avoid permanent hypothyroidism.

Age May Influence the Impact of TRAbs on Thyroid Function and Relapse-Risk in Patients With Graves Disease

CONTEXT

Thyrotropin receptor antibodies (TRAbs) play a crucial role in the pathogenesis of Graves disease (GD). However, factors that influence the association of TRAbs with thyroid hormones and relapse risk in GD remain unclear.

OBJECTIVE

We investigated the associations of TRAbs at diagnosis with thyroid hormones and relapse risk and potential factors that can influence these associations in GD.

DESIGN AND SETTING

A prospective study in an endocrine center in England.

PATIENTS AND MAIN OUTCOME MEASURES

Three hundred eighty-four consecutive patients with GD who had measurements of TRAbs and thyroid hormones at diagnosis. The association of TRAbs with thyroid hormones and relapse risk was assessed through linear regression and Cox proportional hazard models, adjusted for confounders.

RESULTS

TRAbs were nonlinearly associated with thyroid hormones, following a curve with an initial positive slope and a subsequent flattening (P < 0.0001). Higher TRAbs were associated with greater relapse risk [hazard ratio (HR), 1.05 (95% CI, 1.02 to 1.08) per 1-U/L increase]. These associations were modified by age, but not by sex, race, smoking, or thyroid peroxidase antibody levels. In younger participants, increasing TRAbs were associated with higher thyroid hormones and greater relapse risk [HR, 1.13 (95% CI, 1.04 to 1.23) per 1-U/L increase]. In older participants, TRAbs were not associated with thyroid hormones or relapse risk [HR, 0.99 (95% CI, 0.93 to 1.05) per 1-U/L increase.

CONCLUSIONS

In GD, age can influence the effect of TRAbs on thyroid function and relapse risk. TRAbs at diagnosis have better predictive value in younger patients with GD.

Comparison of Five TSH-Receptor Antibody Assays in Graves' disease: results from an observational pilot study

BACKGROUND

Early diagnosis and relapse prediction in Graves' disease influences treatment. We assessed the abilities of four TSH-receptor antibody tests [TRAb] and one cyclic adenosine monophosphate bioassay to predict relapse of Graves' disease.

METHODS

Observational study investigating patients presenting with Graves' disease at a Swiss hospital endocrine referral center or an endocrine outpatient clinic. Main outcomes were diagnosis and relapse of Graves' disease after stop of anti-thyroid drugs. We used Cox regression to study associations of TRAb levels with relapse risk and calculated c-statistics [AUC] to assess discrimination. Blood draws took place as close as possible to treatment initiation.

RESULTS

AUCs ranged from 0.90 (TSAb Biossay by RSR) to 0.97 (IMMULITE TSI by Siemens). Highest sensitivity (94.0%) was observed for IMMULITE TSI and RSR TRAb Fast, while the greatest specificity (97.9%) was found with the EliA anti-TSH-R (by Thermo Fisher). In Cox regression analysis comparing the highest versus the lower quartiles, the highest hazard ratio [HR] for relapse was found for BRAHMS TRAK (by Thermo Fisher) (2.98, 95% CI 1.13-7.84), IMMULITE TSI (2.40, 95% CI 0.91-6.35), EliA anti-TSH-R (2.05, 95% CI 0.82-5.10), RSR Fast TRAb (1.80, 95% CI 0.73-4.43), followed by RSR STIMULATION (1.18, 95% CI 0.46-2.99). Discrimination analyses showed respective AUCs of 0.68, 0.65, 0.64, 0.64, and 0.59.

CONCLUSION

The assays tested had good diagnostic power and relapse risk prediction with few differences among the new assays. Due to the small sample size and retrospective design with possible selection bias, our data need prospective validation.

Graves' Disease: Can It Be Cured?

Whether or not Graves' hyperthyroidism can be really cured, depends on the definition of "cure." If eradication of thyroid hormone excess suffices for the label "cure," then all patients can be cured because total thyroidectomy or high doses of ¹³¹I will abolish hyperthyroidism albeit at the expense of creating another disease (hypothyroidism) requiring lifelong medication with levothyroxine. I would not call this a "cure," which I would like to define as a state with stable thyroid stimulating hormone (TSH), free thyroxine, and triiodothyronine serum concentrations in the normal range in the absence of any thyroid medication. Surgery and radioiodine are unlikely to result in so-defined cures, as their preferable aim as stated in guidelines is to cause permanent hypothyroidism. Discontinuation of antithyroid drugs is followed by 50% recurrences within 4 years; before starting therapy the risk of recurrences can be estimated with the Graves' Recurrent Events After Therapy (GREAT) score. At 20-year follow-up about 62% had developed recurrent hyperthyroidism, 8% had subclinical hypothyroidism, and 3% overt hypothyroidism related to TSH receptor blocking antibodies and thyroid peroxidase antibodies. Only 27% was in remission, and might be considered cured. If the definition of "cure" would also include the disappearance of thyroid antibodies in serum, the proportion of cured patients would become even lower.

Long-term remission following antithyroid drug withdrawal in patients with Graves' hyperthyroidism: parameters with prognostic value

OBJECTIVE

To assess the predictive value of some clinical and biochemical parameters, and of the +49 A/G polymorphism of the CTLA-4 gene, for long-term remission following the withdrawal of antithyroid drugs before starting antithyroid drug therapy.

STUDY DESIGN

Observational, prospective and longitudinal study.

METHODS

Seventy-two patients (11 of whom were men) with newly diagnosed Graves' hyperthyroidism who had been attended consecutively at a University Clinic in a population with sufficient iodine intake were included in the study.

EXCLUSION CRITERIA

patients under the age of 18, pregnant women and non-Caucasian patients. All subjects were treated following a well-defined protocol. Long-term remission was calculated at 12 and 36 months following withdrawal of the antithyroid drug.

RESULTS

Thirty-six of the 72 study subjects experienced a remission of at least 12 months following withdrawal of methimazole, with no differences according to their age or sex. A comparison made between the remission rates seen in both groups yielded significant differences regarding the presence of Graves' orbitopathy, the duration of the treatment with methimazole and the absence of the CTLA-4 G/G genotype. In the univariate and multivariate analyses performed, only lower frequencies of Graves' orbitopathy and an absence of the CTLA-4 G/G genotype were considered independent predictors of long-term remission.

CONCLUSIONS

The absence of Graves' orbitopathy and of the CTLA-4 G/G genotype are independent predictors of long-term remission following a first course of antithyroid drugs.

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.

Antithyroid Drugs

The thionamide drugs, i.e. carbimazole and its metabolite methimazole (MMI), and propylthiouracil (PTU) have extensively been used in the management of various forms of hyperthyroidism over the past eight decades. This review aims to summarize different aspects of these outstanding medications. Thionamides have shown their own acceptable efficacy and even safety profiles in treatment of hyperthyroidism, especially GD in both children and adults and also during pregnancy and lactation. Of the antithyroid drugs (ATDs) available, MMI is the preferred choice in most situations taking into account its better efficacy and less adverse effects accompanied by once-daily dose prescription because of a long half-life and similar cost. Considering the more severe teratogenic effects of MMI, PTU would be the selected ATD for treatment of hyperthyroidism during pre-pregnancy months and the first 16 weeks of gestation. Recent studies have confirmed the efficacy and safety of long-term MMI therapy with low maintenance doses for GD and toxic multinodular goiter. Despite the long-term history of ATD use, there is still ongoing debate regarding their pharmacology and diverse mechanisms of action, viz. their immunomodulatory effects, and mechanisms and susceptibility factors to their adverse reactions.

Antithyroid drug treatment for Graves' disease: baseline predictive models of relapse after treatment for a patient-tailored management

BACKGROUND

Antithyroid drugs (ATDs) are first-line treatment for Graves' hyperthyroidism worldwide, but relapses are frequent. The reliability of individual risk factors to predict at baseline subsequent relapse is poor. Predictive scores grouping single risk factors might help to select the best treatment (pharmacological vs. ablative).

OBJECTIVE

To assess the predictivity of a recently developed score (Clinical Severity Score, CSS) and to compare it with another score (GREAT score).

PATIENTS

A retrospective observational, single-center study was conducted of 387 consecutive, newly diagnosed Graves' patients, who completed an 18-24 months ATD course and were followed for at least 2 years.

RESULTS

Hyperthyroidism relapsed in 185 patients (48%). At diagnosis and before treatment, the relapse group had higher serum TSH-receptor antibody and free thyroxine levels and larger goiters than the remission group, with no differences in Graves' orbitopathy prevalence and severity. In the multivariate analyses, only large goiter size was significantly associated with an increased recurrence hazard ratio. Using CSS, the risk of relapse increased from 36% in the mild category and 49% in the moderate category to 59% in the severe category, with quite a good area under the curve (AUC) (0.60; 95% CI: 0.55; 0.66). GREAT score showed an increase in relapse from 34% for class I (mild) and 49% for class II (moderate) to 64% for class III (severe) (AUC, 0.63; CI: 0.58; 0.68).

CONCLUSIONS

Both CSS and GREAT score are useful, although imperfect, tools to predict at baseline relapse of hyperthyroidism after treatment. In real life they may help the clinician to tailor a treatment for newly diagnosed Graves' hyperthyroidism.

Usefulness of TSH receptor antibodies as biomarkers for Graves' ophthalmopathy: a systematic review

PURPOSE

Over the past several decades, many papers have been published about the usefulness of thyrotropin receptor antibodies (TRAbs) as biomarkers of Graves' ophthalmopathy (GO). However, results have been inconsistent. The purpose of this analysis is to determine a possible cause of these discrepancies and to examine the usefulness of TRAbs as biomarkers for GO, especially 'thyrotropin-binding inhibiting immunoglobulin (TBII)' and 'thyroid-stimulating antibody (TSAb)'.

METHOD

26 articles discussing the association between TRAbs and GO were selected which were then divided into three groups based on the study method and whether or not the patients had been treated for hyperthyroidism. From the results of the papers reviewed, a provisional conclusion was made and a theoretical model on the TBII-TSAb coordinate plane was developed to confirm that conclusion.

RESULTS

TSAb is reported to be significantly or strongly associated with GO in the studies of pre- and post-treated patients for hyperthyroidism. TBII is positively correlated, negatively correlated or uncorrelated with GO in studies of pre-treated patients. However, it is generally agreed upon that TBII and GO are closely correlated in studies of post-treated patients.

CONCLUSION

We conclude that the level of TBII may not be a reliable indicator of the current state of GO in pre-treated patients. Whereas, in post-treated patients, due to changes in the correlation between TBII and TSAb due to the effect of hyperthyroidism treatment, the level of TBII can be a more reliable indicator of GO. Furthermore, the current level of TBII is closely associated with the onset and severity of GO in the future and it can be a valid predictor of GO. However, the TSAb level appears to be more reliable.

2018 European Thyroid Association Guideline for the Management of Graves' Hyperthyroidism

Graves' disease (GD) is a systemic autoimmune disorder characterized by the infiltration of thyroid antigen-specific T cells into thyroid-stimulating hormone receptor (TSH-R)-expressing tissues. Stimulatory autoantibodies (Ab) in GD activate the TSH-R leading to thyroid hyperplasia and unregulated thyroid hormone production and secretion. Diagnosis of GD is straightforward in a patient with biochemically confirmed thyrotoxicosis, positive TSH-R-Ab, a hypervascular and hypoechoic thyroid gland (ultrasound), and associated orbitopathy. In GD, measurement of TSH-R-Ab is recommended for an accurate diagnosis/differential diagnosis, prior to stopping antithyroid drug (ATD) treatment and during pregnancy. Graves' hyperthyroidism is treated by decreasing thyroid hormone synthesis with the use of ATD, or by reducing the amount of thyroid tissue with radioactive iodine (RAI) treatment or total thyroidectomy. Patients with newly diagnosed Graves' hyperthyroidism are usually medically treated for 12-18 months with methimazole (MMI) as the preferred drug. In children with GD, a 24- to 36-month course of MMI is recommended. Patients with persistently high TSH-R-Ab at 12-18 months can continue MMI treatment, repeating the TSH-R-Ab measurement after an additional 12 months, or opt for therapy with RAI or thyroidectomy. Women treated with MMI should be switched to propylthiouracil when planning pregnancy and during the first trimester of pregnancy. If a patient relapses after completing a course of ATD, definitive treatment is recommended; however, continued long-term low-dose MMI can be considered. Thyroidectomy should be performed by an experienced high-volume thyroid surgeon. RAI is contraindicated in Graves' patients with active/severe orbitopathy, and steroid prophylaxis is warranted in Graves' patients with mild/active orbitopathy receiving RAI.

Post-partum and non-post-partum relapsing Graves' hyperthyroidism display different response to anti-thyroid drugs

DESIGN

Graves' disease (GD) patients in remission after a full course of methimazole (MMI) therapy are at risk for a relapse of hyperthyroidism during the post-partum (PP) period, but whether this relapse may display any peculiarity is still unknown. Aim of this study was to compare GD patients undergoing a relapse of hyperthyroidism either in the PP period or not.

METHODS

We retrospectively evaluated forty-three GD female patients in their childbearing age who experienced a relapse of hyperthyroidism. Eighteen of them relapsed in the PP period (i.e. within 12 months after delivery, PP group); the remaining 25 relapsed elsewhere during life (NPP group).

RESULTS

Age at relapse, thyroid volume, thyroid function tests, TRAb titers, smoking habit, presence and degree of orbitopathy and duration of methimazole (MMI) treatment did not differ in the two groups. However, the remission rate was much greater (79%) in the PP as compared with the NPP (32%) group (P = 0.002). A significant reduction in TRAb levels occurred at 12-month MMI treatment in the PP (F = 9.016; P = 0.001), but not in the NPP group (F = 2.433; NS). At 12 months, the PP group had significantly lower mean TRAb levels (0.6 ± 1.1 U/L and 4.5 ± 4.7 U/L in the PP and the NPP group, respectively; P = 0.029).

CONCLUSIONS

Relapsing Graves' hyperthyroidism in the PP period is more prone to undergo a remission after a second course of MMI treatment. In these patients, a conservative therapeutic approach is more appropriate.

Metabolomics for Prediction of Relapse in Graves' Disease: Observational Pilot Study

Background: There is a lack of biochemical markers for early prediction of relapse in patients with Graves' disease [GD], which may help to direct treatment decisions. We assessed the prognostic ability of a high-throughput proton NMR metabolomic profile to predict relapse in a well characterized cohort of GD patients. Methods: Observational study investigating patients presenting with GD at a Swiss hospital endocrine referral center and an associated endocrine outpatient clinic. We measured 227 metabolic markers in the blood of patients before treatment initiation. Main outcome was relapse of hyperthyroidism within 18 months of stopping anti-thyroid drugs. We used ROC analysis with AUC to assess discrimination. Results: Of 69 included patients 18 (26%) patients had a relapse of disease. The clinical GREAT score had an AUC of 0.68 (95% CI 0.63-0.70) to predict relapse. When looking at the metabolomic markers, univariate analysis revealed pyruvate and triglycerides in medium VLDL as predictors with AUCs of 0.73 (95% CI 0.58-0.84) and 0.67 (95% CI 0.53-0.80), respectively. All other metabolomic markers had lower AUCs. Conclusion: Overall, metabolomic markers in our pilot study had low to moderate prognostic potential for prediction of relapse of GD, with pyruvate and triglycerides being candidates with acceptable discriminatory abilities. Our data need validation in future larger trials.

Is Graves' disease a primary immunodeficiency? New immunological perspectives on an endocrine disease

BACKGROUND

Uncertainty about factors influencing the susceptibility and triggers for Graves' disease persists, along with a wide variation in the response to anti-thyroid drugs, currently at approximately 50% of non-responders. The aim of this narrative review is to summarize immunological concepts, with a combined endocrine and immunological perspective, to highlight potential new areas of research.

MAIN TEXT

Relevant studies were identified through a systematic literature search using the PubMed and EMBASE databases in March 2016. No cut-offs regarding dates were imposed. We used the terms "Graves' Disease" or "Basedow" or "thyrotoxicosis" together with the terms "etiology", "pathophysiology", "immunodeficiency", "causality", and "autoimmunity". The terms "orbitopathy", "ophthalmopathy", and "amiodarone" were excluded. Articles in English, French, German, Croatian, Spanish, and Italian were eligible for inclusion.

CONCLUSIONS

While concepts such as the impact of iodine, smoking, human leucocyte antigen, infections, and ethnicity are established, new ideas have emerged. Pertaining evidence suggests the involvement of autoimmunity and immunodeficiency in the pathophysiology of Graves' disease. Recent studies point to specific immunological mechanisms triggering the onset of disease, which may also serve as targets for more specific therapies.

External validation of the GREAT score to predict relapse risk in Graves' disease: results from a multicenter, retrospective study with 741 patients

CONTEXT

First-line treatment in Graves' disease is often done with antithyroid agents (ATD), but relapse rates remain high making definite treatment necessary. Predictors for relapse risk help guiding initial treatment decisions.

OBJECTIVE

We aimed to externally validate the prognostic accuracy of the recently proposed Graves' Recurrent Events After Therapy (GREAT) score to predict relapse risk in Graves' disease.

DESIGN, SETTING AND PARTICIPANTS

We retrospectively analyzed data (2004-2014) of patients with a first episode of Graves' hyperthyroidism from four Swiss endocrine outpatient clinics.

MAIN OUTCOME MEASURES

Relapse of hyperthyroidism analyzed by multivariate Cox regression.

RESULTS

Of the 741 included patients, 371 experienced a relapse (50.1%) after a mean follow-up of 25.6 months after ATD start. In univariate regression analysis, higher serum free T₄, higher thyrotropin-binding inhibitor immunoglobulin (TBII), younger age and larger goiter were associated with higher relapse risk. We found a strong increase in relapse risk with more points in the GREAT score from 33.8% in patients with GREAT class I (0-1 points), 59.4% in class II (2-3 points) with a hazard ratio of 1.79 (95% CI: 1.42-2.27, P < 0.001) and 73.6% in class III (4-6 points) with a hazard ratio of 2.24 (95% CI: 1.64-3.06, P < 0.001).

CONCLUSIONS

Based on this retrospective analysis within a large patient population from a multicenter study, the GREAT score shows good external validity and can be used for assessing the risk for relapse in Graves' disease, which influence the initial treatment decisions.