Long-term prognosis after medical treatment of Graves' disease in a northern Swedish population 2000-2010

Long-term follow-up of treatment outcomes in Graves' disease and toxic nodular disease

PURPOSE

Hyperthyroidism guidelines have not been updated over the past five years, despite numerous data on the subject, and recent studies providing a wide variation in treatment success rates. We aim to compare the effectiveness and safety of treatment modalities in patients with Graves' disease or toxic nodular disease.

METHODS

Single center retrospective cohort study of Graves' disease and toxic nodular disease patients treated between 1983 and 2023.

RESULTS

A total of 411 patients were treated for hyperthyroidism, 245 due to Graves' disease and 166 due to or toxic nodular disease, followed for a median of 7 years. In Graves' disease, 90.2% were treated with antithyroid drugs over 250 cycles, achieving 41.7% cumulative remission. Half of all relapses (50.9%) occurred in the first year, 76.3% in the first three years, and 98.3% within nine years. Treatment periods of 12-24 months showed higher remission and lower relapse rates than longer periods. I-131 was used in 103 cycles with 82.5% remission and 7.1% relapse. A total of 29 thyroidectomies resulted in 100% remission, with no relapse. In toxic nodular disease, surgery was the most frequently used treatment (54.5%), followed by I-131 (37.1%).

CONCLUSION

Our findings support antithyroid drugs as the preferential first-line treatment for Graves' disease, allowing for euthyroidism with minimal adverse effects. Given the propensity for relapse, we suggest a rigorous monitoring, particularly within the first three years. In toxic nodular disease, surgery should be the preferred option, with I-131 being reserved for single adenomas and small goiters.

Control rate of hyperthyroidism and its associated factors after prolonged use of anti-thyroid drugs in a hospital setting, Northwest Ethiopia

Hyperthyroidism is increased synthesis and secretion of thyroid hormones by the thyroid gland resulting in thyrotoxicosis. The modality of therapy for hyperthyroidism includes anti-thyroid drugs, radioiodine and surgery. Anti-thyroid drugs are the only available therapy for hyperthyroid patients in developing world as radioiodine is inaccessible and surgical set up does not exist as required. The aim of this study was to determine the magnitude and predictors of uncontrolled hyperthyroidism among hyperthyroid patients after prolonged anti-thyroid drug use. An institutional-based cross sectional study was conducted at the University of Gondar hospital, Northwest Ethiopia, between April 1, 2022 and October 31, 2022. A consecutive sampling method was used to recruit 317 study subjects. Data were collected through a pre-designed questionnaire. Patients were interviewed to obtain socio-demographic data and relevant medical information. Laboratory analyses were done based on the follow up protocol. Data were entered into EPI Info version 4.6.0.0 (EPI Info, Atlanta) and analyzed in STATA version 14 (Stata Corp LP, Texas, USA). Binary logistic regression model was used to identify variables associated with uncontrolled hyperthyroidism among hyperthyroid patients. P value < .05 was used to declare significant association. A total of 317 patients with hyperthyroidism were included in the study. The median age of the study subjects was 45 years (IQR 36-55 years). Most (95%) of the study participants were females. Toxic multi-nodular goiter was the most common cause of hyperthyroidism (92%), followed by toxic adenoma (5%) and Graves' disease (2%). On multivariate binary logistic regression, large goiter size (AOR: 3.163, 95% CI [1.333-7.506]), severe disease (AOR: 2.275, 95% CI [1.060-4.880]), infrequent iodinated salt intake (AOR: 3.668, 95% CI [1.245-10.802]), and poor adherence to anti-thyroid drug (AOR:15.724, 95% CI [5.542-44.610]) were statistically significant with uncontrolled hyperthyroidism at 12 months of anti-thyroid drug intake. A quarter of patients with hyperthyroidism didn't achieve euthyroid state after 12 months of anti-thyroid drug use. The identified predictors for non-euthyroid state were large goiter size, severe disease, infrequent iodinated salt intake, and poor adherence to anti-thyroid drug.

Hyperthyroidism

Thyrotoxicosis causes a variety of symptoms and adverse health outcomes. Hyperthyroidism refers to increased thyroid hormone synthesis and secretion, most commonly from Graves' disease or toxic nodular goitre, whereas thyroiditis (typically autoimmune, viral, or drug induced) causes thyrotoxicosis without hyperthyroidism. The diagnosis is based on suppressed serum concentrations of thyroid-stimulating hormone (TSH), accompanied by free thyroxine and total or free tri-iodothyronine concentrations, which are raised (overt hyperthyroidism) or within range (subclinical hyperthyroidism). The underlying cause is determined by clinical assessment, detection of TSH-receptor antibodies and, if necessary, radionuclide thyroid scintigraphy. Treatment options for hyperthyroidism include antithyroid drugs, radioactive iodine, and thyroidectomy, whereas thyroiditis is managed symptomatically or with glucocorticoid therapy. In Graves' disease, first-line treatment is a 12-18-month course of antithyroid drugs, whereas for goitre, radioactive iodine or surgery are preferred for toxic nodules or goitres. Evidence also supports long-term treatment with antithyroid drugs as an option for patients with Graves' disease and toxic nodular goitre.

Thyroid function test variability and cardiovascular morbidity in hyperthyroidism

OBJECTIVE

The variability of thyroid function tests (TFTs) during antithyroid drug (ATD) therapy and its association with adverse health outcomes have not been previously studied. The aim of this study was to evaluate the association of TFT variability and cardiovascular morbidity during ATD therapy.

DESIGN

Retrospective cohort study.

PATIENTS AND MEASUREMENTS

Hyperthyroid patients (n = 394) treated with ATD therapy at Tampere University Hospital between March 2016 and December 2018 were followed up for a median time of 1.5 years (interquartile range 0.8-2.0). The coefficients of variation (CVs) of the follow-up thyroid-stimulating hormone (TSH), free thyroxine (fT4) and free triiodothyronine (fT3) measurements were determined. The associations of TFT variability and baseline clinical factors with cardiovascular disease (CVD) -associated hospital visits were assessed with logistic regression analyses.

RESULTS

In the multivariable analyses, age (odds ratio [OR]: 1.06, 95% confidence interval [CI]: 1.03-1.09), male gender (OR: 2.33, 95% CI: 1.03-5.28) and fT4-CV (OR: 1.02, 95% CI: 1.01-1.04) were independent risk factors for cardiovascular morbidity, whereas baseline positive thyrotropin receptor antibodies (TRAbs) were associated with lower cardiovascular morbidity (OR: 0.29, 95% CI: 0.14-0.61). When the patients with baseline TRAb positivity were studied separately, fT4-CV was associated with cardiovascular morbidity (OR: 1.03, 95% CI: 1.00-1.05).

CONCLUSIONS

During ATD therapy, fT4 variability is associated with an increased cardiovascular morbidity. Although positive TRAbs are associated with a lower cardiovascular morbidity compared with hyperthyroidism with negative autoantibodies, the variability of fT4 is associated with cardiovascular morbidity also in patients with positive TRAbs.

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.

Cancer and Mortality Risks of Graves' Disease in South Korea Based on National Data from 2010 to 2019

Purpose

This study aimed to investigate Graves' disease (GD) associated cancer and mortality risk using a Korean population-based study.

Patients and Methods

We included 6435 patients with GD using the Korean National Health Insurance Service-National Sample Cohort database from 2010 to 2019. Data concerning such patients were compared in a 1:5 ratio with age- and sex-matched non-GD group (n=32,175). Eighteen subdivided types of cancer and cancers-in-total were analyzed. In addition to the mortality analysis, subgroup analyses were performed according to age and sex.

Results

After adjustment, the hazard ratio (HR) of the GD group for cancer-in-total was 1.07 (95% confidence interval [CI], 0.91-1.27), showing no difference when compared to the non-GD group. However, among different types of cancer, the thyroid cancer risk of the GD group was higher than that of the non-GD group (HR=1.70; 95% CI, 1.20-2.39). When subdivided by age and sex, the thyroid cancer risk of the GD group in males aged 20-39 years was higher than that of the non-GD group (HR=7.00; 95% CI, 1.48-33.12). The mortality risk of the GD group was not different from that of the non-GD group (HR=0.86; 95% CI, 0.70-1.05).

Conclusion

In South Korea, patients with GD had a higher risk of thyroid cancer than the non-GD group. In particular, males aged 20-39 years with GD were more likely to have thyroid cancer than the non-GD group.

Long-term management of Graves disease: a narrative review

Graves disease (GD) is the most common cause of hyperthyroidism, accounting for more than 90% of cases in Korea. Patients with GD are treated with any of the following: antithyroid drugs (ATDs), radioactive iodine (RAI) therapy, or thyroidectomy. Most patients begin treatment with ATDs, and clinical guidelines suggest that the appropriate treatment period is 12 to 18 months. While RAI treatment and surgery manage thyrotoxicosis by destroying or removing thyroid tissue, ATDs control thyrotoxicosis by inhibiting thyroid hormone synthesis and preserving the thyroid gland. Although ATDs efficiently control thyrotoxicosis symptoms, they do not correct the main etiology of GD; therefore, frequent relapses can follow. Recently, a large amount of data has been collected on long-term ATDs for GD, and low-dose methimazole (MMZ) is expected to be a good option for remission. For the long-term management of recurrent GD, it is important to induce remission by evaluating the patient's drug response, stopping ATDs at an appropriate time, and actively switching to surgery or RAI therapy, if indicated. Continuing drug treatment for an extended time is now encouraged in patients with a high possibility of remission with low-dose MMZ. It is also important to pay attention to the quality of life of the patients. This review aimed to summarize the appropriate treatment methods and timing of treatment transition in patients who relapsed several times while receiving treatment for GD.

Effect of iodine-therapy on hyperthyroidism patients without pre-administration of anti-thyroid therapeutic options

Anti-thyroid treatment and radioiodine are mainly used treatments for patients with thyrotoxicosis. The effect of anti-thyroid drugs (ATDs) on radioactive iodine's therapeutic effectiveness in hyperthyroidism remains controversial. This study aimed to determine the treatment effectiveness and complications in patients with thyrotoxicosis receiving radioiodine treatment with or without adjunctive anti-thyroid drugs in a tertiary endocrinology center in Ahvaz, Iran. A total of 165 patients with thyrotoxicosis (50 males and 115 females) were recruited in this retrospective clinical study. These patients were divided into two groups: one group underwent natural iodine therapy without being treated with anti-thyroid drugs (N= 86), and the other group was first treated with anti-thyroid drugs and then treated with iodine (N= 79). Then, the frequency of euthyroidism, thyroid storm, thyroiditis, hypothyroidism and the time to reach euthyroidism is evaluated. The results showed no difference between the two groups when reaching the euthyroid and the mean numerical mean TSH at the time of hypothyroidism. However, the average dose of iodine received in the concomitant drug group was lower. No thyroid storm was observed in the two groups regarding complications after treatment. Also, the prevalence of hypothyroidism and thyroiditis were not significantly different between the two groups. Iodine therapy with and without the use of anti-thyroid drugs (ATD) in low-risk patients with thyrotoxicosis has no difference in treatment outcomes, response to treatment, and subsequent complications.

Predictive effect of antithyroid antibody for relapse of Graves' disease

BACKGROUND

The remission rate in children with Graves' disease (GD) after 2-6 years of antithyroid drug (ATD) treatment is 40-50%. It has been reported that it is difficult to predict the GD prognosis based on the thryroid stimulating hormone (TSH) receptor antibody (TRAb) level at the cessation of ATD treatment. We studied whether the persistence of negative TRAb at ATD treatment cessation increased the remission rate in pediatric patients with GD.

METHODS

We included 22 patients diagnosed with GD who discontinued ATD treatment after confirmation of negative TRAb on two or more consecutive tests. Remission was defined as the maintenance of normal thyroid function, including serum TSH level, with negative TRAb more than 2 years after ATD discontinuation.

RESULTS

Of the 22 patients, 12 achieved remission (remission rate 54.5%), with no significant between-group difference in the median duration of ATD treatment in the remission and relapse groups (4.4 vs 3.9 years). Of the 10 patients who relapsed, four (40.0%) relapsed within 2 years after ATD discontinuation, and 4 (40.0%) relapsed more than 5 years after ATD discontinuation.

CONCLUSIONS

The persistence of negative TRAb at ATD treatment cessation might indicate prolonged duration of remission but does not increase the final remission rate in patients with childhood-onset GD.

Time to Euthyroidism and Its Determinants Among Thyrotoxicosis Patients on Anti-Thyroid Drug Who Attend to Medical and Ambulatory Clinics of South Tigrai General Hospitals

Purpose

To determine the time to euthyroidism and its determinants among thyrotoxicosis patients on anti-thyroid drug attending the medical and ambulatory clinics of South Tigrai General Hospitals, Ethiopia, 2015–2020.

Methods

A multi-center retrospective cohort study was conducted from March 30, 2020, to July 30, 2020, among adult thyrotoxicosis patients who received anti-thyroid medications in the medical and chronic ambulatory clinics of South Tigrai General Hospitals, Ethiopia. Epi-data manager version 3.1 software was used for data entry and then exported to STATA version 15 for windows for analysis. Cox proportional hazards regression model was used to determine the determinants of time to euthyroidism and the summary measures of the adjusted hazard ratio with a 95% CI were presented, and P-value < 0.05 used to declare the statistical significance.

Results

One hundred and seventy-five (51.9%) thyrotoxicosis patients become euthyroid with the median time to euthyroidism of 9 months, IQR (6–12) months, with a total of 5542 person-months of observation. Age greater than 40 years (AHR = 0.7; 95% CI 0.54–0.96), toxic multi-nodular goiter (AHR = 0.69; 95% CI 0.60–0.87), World Health Organization goiter size three (AHR = 0.78; 95% CI 0.54–0.82) and baseline free thyroxin (AHR = 0.96; 95% CI 0.80–0.99) were the independent determinants of delayed time to euthyroidism.

Conclusion

The time to euthyroidism was longer than the expected time. High baseline free thyroxin, toxic multinodular goiter, elderly patients, and patients with World Health Organization goiter size three were determinants of delayed time to euthyroidism.

[Graves' Disease]

DIAGNOSIS

The diagnosis of Graves' disease is mainly based on ultrasonography and laboratory diagnostics. This includes the determination of the TSH value and the peripheral thyroid hormones. TSH receptor antibody (TRAb) measurement is highly sensitive and specific for the detection of Graves' disease (GD) and helps to distinguish from autoimmune thyroiditis (AIT). However, as recent studies show, some may AIT patients may also reveal TRAb.

THERAPY

Current guidelines recommend primarily the use of thiamazol/carbimazole in GD. Due to the comparatively higher hepatotoxicity, propylthiouracil is not recommended as first line therapy. In case of relapse during 12 up to 18 months of antithyroid drug therapy or after a frustrating attempt at cessation, definitive therapy should be considered. Alternatively, in accordance with the current recommendations of the European Thyroid Association, drug therapy may be continued for up to 12 months after initial diagnosis.

PREGNANCY

The treatment of active GD during pregnancy is problematic due to diaplacental crossing of peripheral thyroid hormones, TSH receptor stimulating antibodies and antithyroid drugs. According to current guidelines, PTU is recommended during the first 16 weeks of pregnancy, whereas for the 2nd and 3 rd trimester no special recommendations are given. After that, you can choose which antithyroid drug might be used. The aim of antithyroid drug therapy during pregnancy is to achieve a suppressed TSH value together with normal or slightly increased fT4 while using lowest effective dose of antithyroid drug.

IMMUNE CHECKPOINT INHIBITORS (ICI)

The most common endocrine side effect with this therapy is thyroid dysfunction. Hyperthyroidism; occur most frequently in combination therapy (CTLA-4 / anti-PD-1 therapy) ICI mainly causes destructive thyroiditis with lymphocytic infiltration; GD is absolutely rare in this context and only few cases are described.

Treatment Modality and Risk of Heart Failure in Patients With Long-Standing Graves' Disease: A Nationwide Population-Based Cohort Study

Background

Optimal treatment for persistent Graves' disease following 12-18 months of treatment with anti-thyroid drugs (ATDs) is unclear. Given the increased risk of cardiovascular morbidity and mortality with hyperthyroidism, assessing the risk of cardiovascular events associated with different treatment modalities after the conventional ATD course would be valuable in determining the appropriate next-line therapy.

Methods

This retrospective cohort study included data from the Korean National Health Insurance database of 16,882 patients with newly diagnosed hyperthyroidism who received primary ATD treatment for 24 months. Patients were categorized based on the treatment they received after receiving ATD for 24 months: continued ATD for at least 12 more months (ATD group), radioiodine ablation (RIA) with remission (RIA group 1), and RIA without remission (RIA group 2). The incidence and risk of heart failure (HF), the leading cause of cardiovascular mortality in hyperthyroidism, were compared between patients and age-and sex-matched controls.

Results

There were 16,516 (97.8%) patients in the ATD group, 230 (1.4%) in RIA group 1, and 136 (0.8%) in RIA group 2. Compared to that of controls, a significant difference in the cumulative incidence of HF was observed according to second-line treatment modality after adjusting for covariates; the risk was highest in patients in RIA group 2, with a hazard ratio (HR) of 2.54 (95% confidence interval (CI) 1.60-4.03), followed by those in the ATD group, with an HR of 1.23 (95% CI 1.20-1.36). Patients in RIA group 1 were not at an increased risk of HF compared to their matched controls (HR 0.77; 95% CI 0.38-1.54). When patients in the ATD group were further classified by the duration of ATD treatment at one-year intervals, the risk of HF was higher in patients with longer ATD use (p for linear trend < 0.001).

Conclusions

In patients with long-standing hyperthyroidism treated with conventional duration of ATD therapy, the risk of HF was attenuated by RIA with remission of hyperthyroidism and increased as ATD was required for longer duration. To reduce the risk of HF, resolution of hyperthyroidism with RIA should be considered in patients with long-standing Graves' disease.

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.

Prevalence of thyroid eye disease in Graves' disease: A meta-analysis and systematic review

OBJECTIVE

Thyroid eye disease (TED) is a debilitating condition that frequently manifests in patients suffering from Graves' disease (GD). This study aims to analyse the prevalence of TED among GD patients, with a focus on geographical region-specific rates.

METHODS

Medline and Embase were searched for articles examining TED prevalence on April 2020, and articles were retrieved and sieved. Statistical analysis was performed after Freeman-Tukey double arcsine transformation. Thereafter, results were pooled with random effects by DerSimonian and Laird model.

RESULTS

Fifty-seven articles involving 26,804 patients were included in the review. The overall pooled prevalence of TED was 40% (CI: 0.32 to 0.48) and by continent was 38% (CI: 0.31 to 0.46) for Europe, 44% (CI: 0.32 to 0.56) for Asia, 27% (CI: 0.06 to 0.56) for North America and 58% (CI: 0.55 to 0.61) for Oceania. The prevalence of TED in Southeast Asia was 35% (CI: 0.24 to 0.47) and Middle East 48% (CI: 0.19 to 0.78). Subgroup analysis showed regions with predominantly Caucasians (37%; CI: 0.28 to 0.46) had a lower prevalence of TED compared to Asians (45%; CI: 0.33 to 0.58). The pooled prevalence of lid retraction was 57% (CI: 0.39 to 0.74), proptosis 57% (CI: 0.48 to 0.65), diplopia 36% (CI: 0.24 to 0.48) and ocular hypertension 13% (CI: 0.06 to 0.19).

CONCLUSION

A substantial proportion of patients with GD have TED and often manifest as lid retraction, proptosis and diplopia. Early detection through active screening might help to mitigate the progression of TED and its associated complications.

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.

A Study on Nonthermal Irreversible Electroporation of the Thyroid

Background:

Nonthermal irreversible electroporation is a minimally invasive surgery technology that employs high and brief electric fields to ablate undesirable tissues. Nonthermal irreversible electroporation can ablate only cells while preserving intact functional properties of the extracellular structures. Therefore, nonthermal irreversible electroporation can be used to ablate tissues safely near large blood vessels, the esophagus, or nerves. This suggests that it could be used for thyroid ablation abutting the esophagus. This study examines the feasibility of using nonthermal irreversible electroporation for thyroid ablation.

Methods:

Rats were used to evaluate the effects of nonthermal irreversible electroporation on the thyroid. The procedure entails the delivery of high electric field pulses (1-3 kV/cm, 100 microseconds) between 2 surface electrodes bracing the thyroid. The right lobe was treated with various nonthermal irreversible electroporation pulse sequences, and the left was the control. After 24 hours of the nonthermal irreversible electroporation treatment, the thyroid was examined with hemotoxylin and eosin histological analysis. Mathematical models of electric fields and the Joule heating-induced temperature raise in the thyroid were developed to examine the experimental results.

Results:

Treatment with nonthermal irreversible electroporation leads to follicular cells damage, associated with cell swelling, inflammatory cell infiltration, and cell ablation. Nonthermal irreversible electroporation spares the trachea structure. Unusually high electric fields, for these types of tissue, 3000 V/cm, are needed for thyroid ablation. The mathematical model suggests that this may be related to the heterogeneous structure of the thyroid-induced distortion of local electric fields. Moreover, most of the tissue does not experience thermal damage inducing temperature elevation. However, the heterogeneous structure of the thyroid may cause local hot spots with the potential for local thermal damage.

Conclusion:

Nonthermal irreversible electroporation with 3000 V/cm can be used for thyroid ablation. Possible applications are treatment of hyperthyroidism and thyroid cancer. The highly heterogeneous structure of the thyroid distorts the electric fields and temperature distribution in the thyroid must be considered when designing treatment protocols for this tissue type.

High neutrophil-to-lymphocyte ratio is associated with relapse in Graves' disease after antithyroid drug therapy

PURPOSE

Antithyroid drugs (ATDs) are effective in controlling hyperthyroidism due to Graves' disease (GD); however, long-term remission rates are low. The neutrophil-to-lymphocyte ratio (NLR) is a useful prognostic marker in many inflammatory diseases. We aimed to evaluate whether NLR can be used as a prognostic marker for relapse in patients with GD after ATD therapy.

METHODS

This retrospective cohort study included 108 patients with newly diagnosed GD who achieved remission after ATD therapy and were followed-up for >12 months after ATD discontinuation. The primary outcome was relapse-free survival (RFS).

RESULTS

Patients were classified into two groups according to baseline NLR: low NLR group with NLR < 1.14 (n = 59; 55%) and high NLR group with NLR ≥ 1.14 (n = 49; 45%). During the median follow-up of 6.5 years, disease relapse after a year of ATD withdrawal occurred in 23 (21%) patients. The patients with high NLR had poorer RFS than those with low NLR, and RFS curves were significantly different between the two groups (p = 0.002). In multivariate analysis, a high NLR (OR = 4.22, p = 0.016) was an independent prognostic factor for relapse in patients with GD after adjusting for age, sex, goiter, orbitopathy, thyroid hormone levels, thyrotropin binding inhibiting immunoglobulin titer, and the duration of ATD therapy.

CONCLUSIONS

This study showed that NLR can be an early and cost-effective prognostic biomarker for relapse in patients with GD after ATD therapy. Further studies are needed to validate the prognostic role of NLR in GD.

Corticosteroid Pulse Therapy for Graves' Ophthalmopathy Reduces the Relapse Rate of Graves' Hyperthyroidism

Background: A course of anti-thyroid drugs (ATD) is the most common first line treatment for Graves' hyperthyroidism. However, hyperthyroidism relapse is frequent (30-70%). Due to the autoimmune nature of Graves' disease, the immunosuppressive treatment used for active Graves' orbitopathy (GO) may reduce the relapses after ATD discontinuation. Objective: To evaluate the recurrence rate in Graves' patients who, in addition to standard ATD, were treated or not treated with parenteral methylprednisolone (MPDS) for GO. Methods: Single-center retrospective study in a continuous series of 162 newly diagnosed Graves' patients, with or without GO, all gone into remission and followed-up until hyperthyroidism recurrence or at least 4 years after ATD discontinuation. Patients with moderate-severe active GO underwent middle dose MPDS treatment according to the EuGoGo guidelines. Cox proportional-hazard model was used to comparatively evaluate the risk of recurrence and the predictive factors in patients treated or not treated with MPDS pulse therapy. Results: MPDS treatment was the most significant factor that independently correlated with a reduced risk of hyperthyroidism relapse (HR = 0.53, 95% C.I. = 0.31-0.89). FT3 and female sex were also independent protective factors, while age almost reached the significance level, p = 0.062. The efficacy of MPDS was very high in patients aged <40 years (42.1% decrease in relapses, p < 0.01) but it was not significant in older patients. Discussion: Our study found that after ATD discontinuation the frequency of Graves' hyperthyroidism relapse was reduced in patients treated with MPDS pulse therapy for GO. This effect was more marked in young patients.

The Long-Term Outcome of Treatment for Graves' Hyperthyroidism

Background: The treatment efficacy of antithyroid drug (ATD) therapy, radioactive iodine (¹³¹I), or surgery for Graves' hyperthyroidism is well described. However, there are a few reports on the long-term total outcome of each treatment modality regarding how many require levothyroxine supplementation, the need of thyroid ablation, or the individual patient's estimation of their recovery. Methods: We conducted a pragmatic trial to determine the effectiveness and adverse outcome in a patient cohort newly diagnosed with Graves' hyperthyroidism between 2003 and 2005 (n = 2430). The patients were invited to participate in a longitudinal study spanning 8 ± 0.9 years (mean ± standard deviation) after diagnosis. We were able to follow 1186 (60%) patients who had been treated with ATD, ¹³¹I, or surgery. We determined the mode of treatment, remission rate, recurrence, quality of life, demographic data, comorbidities, and lifestyle factors through questionnaires and a review of the individual's medical history records. Results: At follow-up, the remission rate after first-line treatment choice with ATD was 45.3% (351/774), with ¹³¹I therapy 81.5% (324/264), and with surgery 96.3% (52/54). Among those patients who had a second course of ATD, 29.4% achieved remission (vs. the 45.3% after the first course of ATD). The total number of patients who had undergone ablative treatment was 64.3% (763/1186), of whom 23% (278/1186) had received surgery, 43% (505/1186) had received ¹³¹I therapy, including 2% (20/1186) who had received both surgery and ¹³¹I. Patients who received ATD as first-line treatment and possibly additional ATD had 49.7% risk (385/774) of having undergone ablative treatment at follow-up. Levothyroxine replacement was needed in 23% (81/351) of the initially ATD treated in remission, in 77.3% (204/264) of the ¹³¹I treated, and in 96.2% (50/52) of the surgically treated patients. Taken together after 6-10 years, and all treatment considered, normal thyroid hormone status without thyroxine supplementation was only achieved in 35.7% (423/1186) of all patients and in only 40.3% of those initially treated with ATD. The proportion of patients that did not feel fully recovered at follow-up was 25.3%. Conclusion: A patient selecting ATD therapy as the initial approach in the treatment of Graves' hyperthyroidism should be informed that they have only a 50.3% chance of ultimately avoiding ablative treatment and only a 40% chance of eventually being euthyroid without thyroid medication. Surprisingly, 1 in 4 patients did not feel fully recovered after 6-10 years. The treatment for Graves' hyperthyroidism, thus, has unexpected long-term consequences for many patients.

When should antithyroid drug therapy to reduce the relapse rate of hyperthyroidism in Graves' disease be discontinued?

OBJECTIVE

The use of antithyroid drug (ATD) therapy in patients with Graves' disease (GD) hyperthyroidism has been increasing, but ATD therapy is associated with a higher relapse rate. We aimed to evaluate clinical factors for predicting relapse of GD after ATD therapy.

METHODS

Patients (n = 149) with newly diagnosed GD who achieved remission of hyperthyroidism after ATD therapy (≥6 months) were followed up for >18 months after ATD withdrawal. We evaluated the predictive factors of relapse during a median of 6.9 years of follow-up.

RESULTS

Disease relapse occurred in 52 patients (34.9%). By multivariate analyses, a duration of the minimum maintenance dose therapy (MMDT) of <6 months was a significant factor in disease relapse (hazard ratio [HR], 2.58; 95% confidence interval [CI], 1.47-4.52; p < 0.001), and a T3/free T4 (fT4) ratio > 120 at ATD withdrawal was significantly more frequent in patients with relapse (HR 2.43; 95% CI, 1.36-4.34; p = 0.002). In the prediction-of-relapse model, the likelihood of relapse was greater in the high-risk group, which had a short MMDT duration and a T3/fT4 ratio ≥120 (HR, 5.81; 95% CI, 2.52-13.39; p < 0.001) and the intermediate-risk group, which had a short MMDT duration or a T3/fT4 ratio < 120 (HR, 2.77; 95% CI, 1.26-6.13; p < 0.001), than in the low-risk group, which had a long MMDT duration and a T3/fT4 ratio < 120.

CONCLUSION

An MMDT longer than 6 months and a high T3/fT4 ratio at ATD withdrawal were independent predictors of relapse in patients who achieved initial remission after ATD for GD. These factors could be used to determine the optimal time to withdraw ATD during the treatment of GD hyperthyroidism.

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.

Normalization of thyroid function tests among thyrotoxicosis patients attending a University Hospital in North-West Ethiopia

Background

Thyrotoxicosis is a clinical state that results from inappropriately high thyroid hormone action in tissues. Although it is one of the common endocrine disorders, there is scarcity of data on the management of thyrotoxicosis in Africa, particularly in Ethiopia. The aim of this study was to investigate treatment outcomes and determinants of treatment outcomes among hyperthyroid patients on antithyroid drugs attending a teaching hospital in Ethiopia.

Methods

A retrospective cohort study was conducted on medical records of patients with thyrotoxicosis who had attended the medical inpatient ward and chronic ambulatory clinic of the University of Gondar Comprehensive Specialized Hospital in Ethiopia between June 2013 and April 2018. Descriptive statistics were used to summarize socio-demographic and other baseline information. A cox regression method was used to determine factors associated with normalization of thyroid function tests (TFTs). All statistical tests were performed using STATA version 14.

Results

Data from a total 211 patients were eventually analyzed. The mean age of the patients was 47.25 ± 14.26 years with female majority (94.31%). The most common etiology was toxic multinodular goiter (54.90%). Because methimazole or carbimazole are not easily available locally, all of the patients included in this study were taking propylthiouracil (PTU). Nearly 9 out of 10 patients (90.38%) had symptom resolution within a mean period of 5.37 (± 6.59) months. Sixty-two (29.81%) and 122 (58.65%) patients achieved normalization of TSH and FT4, respectively during the study period. The mean time to normalization of TSH and FT4 was 13 (±13.28) and 11.53 (±13.39) months, respectively. On the other hand, T3 and all three TFTs were normalized only among 79 (38.16%) and 55 (26.32%) patients, respectively. Older age and higher baseline FT4 levels were shown to modestly reduce the chances of achieving normalization of TSH.

Conclusion

Though PTU is not the preferred antithyroid agent in the management of thyrotoxicosis, all patients used PTU for the management of hyperthyroidism. All TFTs were normalized in only less than one-third of the participants. Resolution of symptoms took longer period of time than expected.

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.

DISEASE PRESENTATION AND REMISSION RATE IN GRAVES DISEASE TREATED WITH ANTITHYROID DRUGS: IS GENDER REALLY A FACTOR?

OBJECTIVE

Male gender is considered an adverse prognostic factor for remission of Graves disease treatment with antithyroid drugs (ATDs), although published data are conflicting. This often results in early consideration of radioiodine treatment and surgery for men. Our objective was to compare disease presentation and outcome in men versus women treated with ATDs.

METHODS

Retrospective study of 235 patients (64 men, 171 women) with Graves disease who were evaluated for features at presentation and outcome at the end of follow-up between 2010 and 2015.

RESULTS

Disease presentation was similar in men and women for age at diagnosis (41.4 ± 14 years vs. 40 ± 15 years), duration of follow-up (6.6 ± 7 years vs. 7.7 ± 6 years), rates of comorbid autoimmune diseases, and rate of Graves ophthalmopathy. Smoking was more prevalent in males (31% vs. 15%; P = .009). Free thyroxine and triiodothyronine levels were comparable. ATDs were first-line treatment in all males and in 168 of 171 females, for a median duration of 24 and 20 months, respectively ( P = .55). Remission rates were 47% in men and 58% in women ( P = .14). Males had fewer adverse events (9% vs. 18%) and treatment discontinuation (5% vs. 16%). Disease recurrence was comparable (14% vs. 20%; P = .32), as was requirement for second-line treatment, either radioiodine therapy or thyroidectomy.

CONCLUSION

Graves disease presentation is similar in men and women. Men treated with ATDs have high remission rates and similar recurrence rates compared to women, with fewer adverse events and less discontinuation of treatment. ATDs are an attractive first-line treatment for both genders.

ABBREVIATIONS

ATA = American Thyroid Association; ATD = antithyroid drug; GO = Graves ophthalmopathy; T3 = triiodothyronine; T4 = thyroxine; TSH = thyroid-stimulating hormone.

Optimal iodine supplementation during antithyroid drug therapy for Graves' disease is associated with lower recurrence rates than iodine restriction

OBJECTIVE

A relationship between iodine intake and the effectiveness of antithyroid drug (ATD) therapy for Graves' disease (GD) has been suggested, and strict restriction of iodine intake has been tried in the treatment of GD in some studies. However, it is unclear whether dietary iodine supplementation improves the prognosis of ATD therapy for GD. This study aimed to clarify whether optimal iodine supplementation during antithyroid drug therapy for GD is associated with lower recurrence rates than iodine restriction.

METHODS

This was a prospective randomized trial of newly diagnosed patients with GD. Patients with newly diagnosed GD were recruited. After ATD therapy and strict dietary iodine restriction for 1 month, patients (n = 459) were randomly assigned to iodine-supplemented and iodine-restricted groups. After exclusion, 405 patients finally completed the study. The iodine-supplemented group included 203 patients (61 males and 142 females) with an average age of 32.2 ± 10.5 years (17-65 years), and the iodine-restricted group included 202 patients (61 males and 141 females) with an average age of 31.9 ± 11.8 years (16-64 years). Patients in the iodine-supplemented group were given about 10 grams of iodized salt every day, while the iodine-restricted group received noniodized salt with low-iodine or noniodine diet. The dietary iodine intervention lasted for 24 months. Urinary iodine concentration (UIC), thyrotropin receptor antibody (TRAb), free T3 (FT3), free T4 (FT4) and thyrotropin (TSH) of 2 groups were measured every 3 months. The recurrence rates within 12 months after withdrawal of ATD were evaluated.

RESULTS

UIC in the iodine-supplemented group was within the recommended range for optimal iodine intake (135-162 μg/L) and was significantly higher than that in iodine-restricted group (30-58 μg/L). Within 12 months of withdrawal of ATD, the total recurrence rate in the iodine-supplemented group was 35.5%, significantly lower than in the iodine-restricted group, which was 45.5%.

CONCLUSION

Optimal dietary iodine supplementation during antithyroid drug therapy for GD is associated with lower recurrence rates than iodine restriction, and therefore, diet control with strict iodine restriction might be an adverse factor in the management of GD.

Clinical Feasibility of Continuously Monitored Data for Heart Rate, Physical Activity, and Sleeping by Wearable Activity Trackers in Patients with Thyrotoxicosis: Protocol for a Prospective Longitudinal Observational Study

BACKGROUND

Thyrotoxicosis is a common disease caused by an excess of thyroid hormones. The prevalence of thyrotoxicosis about 2% and 70-90% of thyrotoxicosis cases are caused by Graves' disease, an autoimmune disease, which has a high recurrence rate when treated with antithyroid drugs such as methimazole or propylthiouracil. The clinical symptoms and signs of thyrotoxicosis include palpitation, weight loss, restlessness, and difficulty sleeping. Although these clinical changes in thyrotoxicosis can be detected by currently available wearable activity trackers, there have been few trials of the clinical application of wearable devices in patients with thyrotoxicosis.

OBJECTIVE

The aim of this study is to investigate the clinical applicability of wearable device-generated data to the management of thyrotoxicosis. We are analyzing continuously monitored data for heart rate, physical activity, and sleep in patients with thyrotoxicosis during their clinical course after treatment.

METHODS

Thirty thyrotoxic patients and 10 control subjects were enrolled in this study at Seoul National University Bundang Hospital. Heart rate, physical activity, and sleep are being monitored using a Fitbit Charge HR or Fitbit Charge 2. Clinical data including anthropometric measures, thyroid function test, and hyperthyroidism symptom scale are recorded.

RESULTS

Study enrollment began in December 2016, and the intervention and follow-up phases are ongoing. The results of the data analysis are expected to be available by September 2017.

CONCLUSIONS

This study will provide a foundational feasibility trial of the clinical applications of biosignal measurements to the differential diagnosis, prediction of clinical course, early detection of recurrence, and treatment in patients with thyrotoxicosis.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03009357; https://clinicaltrials.gov/ct2/show/NCT03009357 (Archived by WebCite at http://www.webcitation.org/6wh4MWPm2).

The Influence of Juvenile Graves' Ophthalmopathy on Graves' Disease Course

Purpose

To investigate juvenile Graves' ophthalmopathy (GO) signs and compare Graves' disease (GD) course in patients with or without GO.

Patients and Methods

There were analyzed data (visual acuity, proptosis, palpebral fissure measurements, clinical activity score (CAS), and the course of GD) of 67 children who have been newly diagnosed with GD. 26.9% of patients with GD had signs of ophthalmopathy (GO+), and 73.1% were without ophthalmopathy (GO−).

Results

Upper eyelid retraction (72.3%), proptosis (66.7%), and soft tissue changes (27.8−38.9%) were in GO+ patients. The palpebral fissure, CAS, and proptosis values were greater in the GO+ group than in the GO− group (p < 0.001). GD course in GO+ patients was longer than that in GO− patients (p < 0.001). The duration of the first remission was longer in GO− than in GO+ patients (p < 0.001). The duration of first remission was longer than one year for 61.2% in GO− and 33.3% in GO+ patients (p < 0.02).

Conclusion

The common manifestations of juvenile GO patients were upper eyelid retraction, proptosis, and soft tissue involvement. The study demonstrates that pediatric patients with GO are more likely to have a severe course of autoimmune thyroid disease.

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 for Graves' Disease and Implications for Recurrence

Graves' disease (GD) is the most common cause of hyperthyroidism worldwide. Current therapeutic options for GD include antithyroid drugs (ATD), radioactive iodine, and thyroidectomy. ATD treatment is generally well accepted by patients and clinicians due to some advantages including normalizing thyroid function in a short time, hardly causing hypothyroidism, and ameliorating immune disorder while avoiding radiation exposure and invasive procedures. However, the relatively high recurrence rate is a major concern for ATD treatment, which is associated with multiple influencing factors like clinical characteristics, treatment strategies, and genetic and environmental factors. Of these influencing factors, some are modifiable but some are nonmodifiable. The recurrence risk can be reduced by adjusting the modifiable factors as much as possible. The titration regimen for 12-18 months is the optimal strategy of ATD. Levothyroxine administration after successful ATD treatment was not recommended. The addition of immunosuppressive drugs might be helpful to decrease the recurrence rate of GD patients after ATD withdrawal, whereas further studies are needed to address the safety and efficacy. This paper reviewed the current knowledge of ATD treatment and mainly focused on influencing factors for recurrence in GD patients with ATD treatment.

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.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Relapse prediction in Graves´ disease: Towards mathematical modeling of clinical, immune and genetic markers

PROBLEM

Graves' disease (GD) is an important and prevalent thyroid autoimmune disorder. Standard therapy for GD consists of antithyroid drugs (ATD) with treatment periods of around 12 months but relapse is frequent. Since predictors for relapse are difficult to identify the individual decision making for optimal treatment is often arbitrary.

METHODS

After reviewing the literature on this topic we summarize important factors involved in GD and with respect to their potential for relapse prediction from markers before and after treatment. This information was used to design a mathematical model integrating thyroid hormone parameters, thyroid size, antibody titers and a complex algorithm encompassing genetic predisposition, environmental exposures and current immune activity in order to arrive at a prognostic index for relapse risk after treatment.

CONCLUSION

In the search for a tool to analyze and predict relapse in GD mathematical modeling is a promising approach. In analogy to mathematical modeling approaches in other diseases such as viral infections, we developed a differential equation model on the basis of published clinical trials in patients with GD. Although our model needs further evaluation to be applicable in a clinical context, it provides a perspective for an important contribution to a final statistical prediction model.

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

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

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.

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.

Technetium uptake predicts remission and relapse in Grave's disease patients on antithyroid drugs for at least 1 year in South Indian subjects

CONTEXT

Most of the information on remission related factors in Grave's disease are derived from Western literature. It is likely that there may be additional prognostic factors and differences in the postdrug treatment course of Grave's disease in India.

AIM

To study factors which predict remission/relapse in Grave's disease patients from South India. Also to establish if technetium (Tc) uptake has a role in predicting remission.

SUBJECTS AND METHODS

Records of 174 patients with clinical, biochemical, and scintigraphic criteria consistent with Grave's disease, seen in our Institution between January 2006 and 2014 were analyzed. Patient factors, drug-related factors, Tc-99m uptake and other clinical factors were compared between the remission and nonremission groups.

STATISTICAL ANALYSIS USED

Mann-Whitney U-test and Chi-square tests were used when appropriate to compare the groups.

RESULTS

Fifty-seven (32.7%) patients attained remission after at least 1 year of thionamide therapy. Of these, 11 (19.2%) patients relapsed within 1 year. Age, gender, goiter, and presence of extrathyroidal manifestations were not associated with remission. Higher values of Tc uptake were positively associated with remission (P- 0.02). Time to achievement of normal thyroid function and composite dose: Time scores were significantly associated with remission (P - 0.05 and P - 0.01, respectively). Patients with lower FT4 at presentation had a higher chance of remission (P - 0.01). The relapse rates were lower than previously reported in the literature. A higher Tc uptake was found to be significantly associated with relapse also (P - 0.009).

CONCLUSION

The prognostic factors associated with remission in Graves's disease in this South Indian study are not the same as that reported in Western literature. Tc scintigraphy may have an additional role in identifying people who are likely to undergo remission and thus predict the outcome of Grave's disease.

Outcome Prediction of Treatment of Graves' Hyperthyroidism with Antithyroid Drugs

Graves' disease is the most common cause of hyperthyroidism in iodine-replete areas and is ultimately due to antibodies interacting with the TSH receptor on thyroid follicular cells [TSH-receptor antibody (TRAb)]. Antithyroid drugs (ATDs) belonging to the family of thionamides are the first-line treatment in Europe. ATD treatment is commonly continued for 18-24 months. Its major limitation is the high rate of relapses after drug withdrawal. Factors particularly bound to subsequent relapses are the large thyroid volume, smoking habit, persistence of TRAb in the circulation at the end of treatment, and the post-partum period. Under these conditions, consideration should be given to a definitive therapy for hyperthyroidism (radioiodine treatment, thyroidectomy), particularly if the patient is at risk of cardiovascular complications that might be exacerbated by persistence or recurrence of hyperthyroidism.

Relapse following antithyroid drug therapy for Graves' hyperthyroidism

PURPOSE OF REVIEW

In most patients with hyperthyroidism caused by Graves' disease, antithyroid drug (ATD) therapy is followed by a gradual amelioration of the autoimmune abnormality, but about half of the patients will experience relapse of hyperthyroidism when the ATDs are withdrawn after a standard 1 to 2 years of therapy. This is a major drawback of ATD therapy, and a major concern to patients. We review current knowledge on how to predict and possibly reduce the risk of such relapse.

RECENT FINDINGS

Several patient and disease characteristics, as well as environmental factors and duration of ATD therapy, may influence the risk of relapse after ATD withdrawal. Depending on the presence of such factors, the risk of relapse after ATD withdrawal may vary from around 10 to 90%. Risk factors for relapse should be taken into account when choosing between therapeutic modalities in a patient with newly diagnosed disease, and also when discussing duration of ATD therapy.

SUMMARY

Prolonged low-dose ATD therapy may be feasible in patients with high risk of relapse, such as children and patients with active Graves' orbitopathy, and in patients with previous relapse who prefer such therapy rather than surgery or radioiodine.