Medical Treatment of Hyperthyroidism; Efficacy and Safety Considerations.

Following the conventional 12-18month antithyroid drug (ATD) treatment in Graves' disease (GD), 50% of patients experience relapse of hyperthyroidism. The aim of this systematic scoping review was critical appraisal of duration of ATD therapy in the last 80years. 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. We described major progress regarding the duration of ATD therapy and related outcomes at every 20years. 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 18-24months versus 6months 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, 12-18months of ATD therapy was arbitrarily chosen as the appropriate option. According to recent studies, persistent normalization of TRAb occurs after 5years of methimazole therapy and ATD treatment of > 60months could offer a 4-year remission rate of 85%. Long-term ATD treatment for more than 60months 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.

Graves’ disease is the most common cause of hyperthyroidism in children. Antithyroid drug (ATD) treatment is recommended as the initial treatment, leading to a marked improvement in most symptoms within 1 month of treatment initiation. Remission is achieved in 30% of children after a first course of ATD. Alternative treatments, such as radioactive iodine or thyroidectomy, are considered in cases of relapse, lack of compliance or ATD toxicity. The risk of relapse after a first course of ATD treatment for a median period of 2 years has been shown to be higher in patients with severe biochemical hyperthyroidism at diagnosis, young children and patients of non-Caucasian origin. Relapse risk decreases with the duration of the first course of ATD treatment, highlighting the positive impact of a long period of primary ATD treatment on outcome. The identification of predictive factors has made it possible to stratify patients according to the risk of relapse after ATD treatment, leading to improvements in patient management by facilitating the identification of patients requiring long-term ATD or early alternative therapy. Long-term careful follow-up is needed to determine the efficacy of disease management during childhood.

Current literature suggests 12-18 months of antithyroid drug (ATD) treatment for patients with Graves' disease, but the risk of relapse is high. Although some studies reported better outcomes of long-term ATD treatment, recent data that suggest the optimal treatment duration are limited. We performed a multicenter retrospective cohort study of 908 patients newly diagnosed with Graves' disease between 2006 and 2013. The relapse rate according to ATD treatment duration was analyzed. After initial ATD treatment, 338 patients (37.2%) had relapsed. The relapse rate according to ATD treatment duration was 42.4% at 1 year, 38.5% at 2 years, 33.8% at 3 years, 31.7% at 4 years, 30.2% at 5 years, 27.8% at 6 years, and 19.1% at more than 6 years, respectively, demonstrating a significant decreasing trend (p = 0.003). In a multivariable Cox regression analysis, ATD treatment duration was an independent risk factor for relapse (p = 0.043). The longer that ATD therapy is used, the lower the relapse rate is in patients with Graves' disease. Long-term ATD treatment may be considered in Graves' patients who do not show complications or an economic burden from hyperthyroidism.

In Europe antithyroid drug (ATD) therapy is the preferred initial treatment for patients with a first episode of Graves' disease. Results of long-term recurrence rates following ATD therapy are conflicting. The main goal was to assess long-term recurrence rate after ATD treatment. Secondarily we tried to verify chemical and clinical findings (thyrotropin receptor antibodies (TRAb), duration of primary treatment, age and goitre size) as predictive factors. Records of 94 patients with a first episode of Graves' disease (1990-1995) treated by ATD were retrospectively analyzed. 18 patients were lost for follow up investigations, the remaining 76 (65 women, 11 men, age 16-76 years) patients were followed for 99 (+/- 22) months (mean +/- SD). To verify the predictive factors a logistic regression analysis was done. Among the 76 patients 16 underwent near-total resection (n = 5) or radioiodine therapy (n = 11) after initial ATD treatment. Sixty patients were treated during 19 +/- 16 months (mean +/- SD) with ATDs and were euthyroid when treatment was stopped. Thirteen of the 60 patients (21.7%) remained in remission after discontinuation of ATD therapy, in 42 patients (70%) hyperthyroidism recurred, in four patients (6.7%) ATD could not be stopped, one patient (1.7%) had a persistent hypothyroidism after discontinuation of ATD. Relapse rate was inversely correlated with duration of primary ATD treatment (p < 0.05), but not with TRAb titer at the time of diagnosis nor at the time of ATD discontinuation. Also, no correlation could be noticed with goitre size at the time of diagnosis. An inverse correlation of the age at the time of diagnosis with relapse rate was of only borderline significance (p = 0.055). Initial successful treatment with ATD is followed by a high recurrence rate in our population. Two possible negative predictors of relapse are short duration of primary ATD treatment and young age at the time of diagnosis. TRAb titer at the time of diagnosis or at the time of ATD discontinuation and goitre size seem to have no influence on the outcome.

Background/aim Graves’ disease (GD) is more severe, requires a more complex treatment, and has a lower probability of achieving remission in children than in adults. There is no consensus on the appropriate duration of antithyroid drug (ATD) treatment. Surgical or radioactive iodine (RAI) treatments are not definitive and generally result in permanent hypothyroidism. This study’s goal was examining the effectiveness of ATD treatment in children and adolescents with GD and determining the risk factors of remission and relapse.Materials and methods This retrospective study included 45 patients (36 females and 9 males, median age 12.5 years) aged 4–18 who were diagnosed with GD between 2003 and 2017. All patients initially were treated with an ATD. ATD treatment was discontinued at a mean of 23.2 ± 13.2 months (10–37 months). Results Patients were classified into remission (n = 24) and relapse groups (n = 21). The duration of initial ATD treatment in the remission group was longer (26.91 ± 5.17 months) than in the relapse group (19.09 ± 7.14 months) (P = 0.01). The total ATD treatment duration was statistically longer in the remission group (42.14 ± 14.35 months) than in the relapse group (26.95 ± 16.13 months) (P = 0.03). Conclusion Long-term initial ATD treatment and long-term total ATD treatment were evaluated as positive parameters for the remission of Graves’ disease in children and adolescents. Our findings showed that the chance of long-term remission increases in direct proportion to the initial ATD treatment duration and the total ATD treatment duration.

Background: Considerable uncertainty remains about the pattern of use of treatment options for Graves' disease (GD) and their comparative effectiveness and safety. Methods: Between 2005 and 2013, we identified patients with GD who received antithyroid drugs (ATDs), radioactive iodine (RAI) or surgery, and were represented in a large administrative data set in the United States (OptumLabs® Data Warehouse). Results: We identified 4661 patients with GD: mean age 48 (SD ±14) years, white (63%), and female (80%). Patients received ATD, n = 2817 (60%), RAI, n = 1549 (33%), or surgery, n = 295 (6%). Success rates were 50% for ATD, 93% for RAI, and 99% for surgery. Median time to treatment failure was 6.8 months for ATD and 3 months for RAI and surgery. When patients were required to be on ATD for at least one year before assessing failure, the failure rate decreased to 25%. Adverse effects occurred in 12% of patients receiving ATD, 6% with RAI, and 24% with surgery. Factors associated with treatment success were age >55 years (for ATD) and female sex (for RAI). About 12% of patients receiving ATD continued this treatment for >24 months as initial therapy. When patients failed ATD therapy, the most common second-line therapy was reinitiation of ATD (65%), RAI (26%), and surgery (9%). Overall, 26% of patients remain on ATD therapy (combined first or second line). Conclusions: ATD therapy was the most common GD therapy and demonstrated the lowest efficacy and infrequent significant adverse effect profile. With one fourth of patients remaining on ATD treatment (initial or second modality treatment), it becomes imperative to determine the long-term efficacy, safety, costs, and burdens of this modality of treatment.

Outcomes of childhood-onset Graves' disease (GD) and suggested duration of anti-thyroid drug (ATD) therapy have been controversial. This study aimed to determine long-term outcomes following ATD therapy, including remission and relapse rates. A retrospective study of 265 paediatric patients with GD who were initially treated with ATD was conducted. Long-term outcomes were analysed. Median (IQR) age at diagnosis was 11.5 (9.4, 13.7) years. Duration of ATD treatment was 4.3 (2.3, 6.7) years and time since diagnosis to the enrolment was 7.1 (3.8, 10.9) years. There were 77, 93 and 95 patients who underwent definitive treatment, had ATD discontinuation, and were still being treated with ATD, respectively. The remission rate was 21% (56 out of 265 patients) and relapse rate was 40% (37 out of 93 patients). Cumulative incidence of first remission increased with the duration of ATD treatment with maximum remission rate at 5.3 years following ATD therapy. Among patients who experienced relapse, approximately 50% had disease relapse which occurred within 1 year after ATD discontinuation. Patients with goitre size of less than 3.5 cm, thyroid-stimulating hormone receptor antibody of less than 10 IU/L, no ophthalmopathy at diagnosis and methimazole dose requirement of less than 0.25 mg/kg/day at 1 year after treatment were more likely to achieve remission. Remission rate of childhood-onset GD was relatively low following ATD treatment. Longer-term ATD therapy was associated with increased remission rate. Approximately 50% of patients with relapse had disease relapse within 1 year following ATD discontinuation.

The management of Graves' disease (GD) in children is associated with a dilemma. Although the established initial treatment for GD in children is antithyroid drug (ATD) treatment, the remission rate in children is said to be lower than in adults, and severe propylthiouracil-induced adverse events (AEs) are an issue. Definitive treatments are effective, but they often result in permanent hypothyroidism and the need for lifelong T4 supplementation. The objective of this study was to investigate the outcome of ATD treatment, identify significant predictors of a remission, and evaluate the AEs of ATDs in a large pediatric population of GD patients. We retrospectively assessed the reports of 1138 children up to 18 years of age who had been newly diagnosed with GD at our institution between 1982 and 2006. Their median age at diagnosis was 16 years (range: 3-18 years), and there were 995 females and 143 males. All patients were initially treated with an ATD. Remission was defined as maintenance of euthyroidism for more than 12 months after discontinuing ATD treatment and the absence of any relapses during the follow-up period. Of the 1138 patients, 723 continued on ATD treatment, 271 underwent surgery or radioactive iodine therapy, and 144 dropped out. Of the 723 patients who continued on ATD treatment, ATD treatment was subsequently ongoing in 84 and was discontinued in 639 (median duration of treatment: 3.8 years; range: 0.3-24.8 years). Of the 639 patients who discontinued ATD treatment, 334 (46.2%) achieved a remission, 247 (34.2%) experienced a relapse, and 58 (8.0%) dropped out. The cumulative remission rate increased with the duration of ATD treatment up until five years. No significant predictors of a remission were identified. The overall incidences of AEs associated with methimazole and propylthiouracil were 21.4% and 18.8% respectively. There were no fatal AEs in our population. While most AEs (91.6%) occurred within the first three months of ATD treatment, 2.7% developed more than two years after the start of ATD treatment. Seven of the eight late-onset AEs were induced by propylthiouracil. Long-term ATD treatment is a useful treatment option for GD in children.

Context: Medical therapy of hyperthyroidism has been the Astwood’s gift to medicine. However, controversy remains about its mechanisms of action, the ideal treatment duration, and its proper use in pregnancy. The concept that hyperthyroidism could be controlled ‘indefinitely’ with antithyroid drugs (ATDs) is also a topic of current debate. The purpose of this review was to highlight the pros and cons of long-term ATD therapy. Evidence Acquisition: PubMed, Scopus, Web of Science, and Google Scholar databases were searched for retrieving studies conducted on long-term treatment with ATDs up to Jan 2020. The final selection of the papers was made based on their relevancy with the safety and efficacy of long-term treatment with ATDs. Results: The main drawback of the ATD treatment is the high relapse rate after drug discontinuation. On the other hand, ATDs may have a favorable immunosuppressive effect, either primarily, in the diminution of thyroid-specific autoimmunity, or secondarily, as a result of controlling the hyperthyroid state, hence keeping patients in a euthyroid state for a prolonged period to diminish autoimmunity and hyperthyroid relapse. This often calls for long-term use of methimazole, but with the lowest possible dose to minimize the risk of side effects. Emerging evidence demonstrates that the long-term treatment with ATDs has relatively few adverse events, most of which arise within the starting months of treatment and in subjects on larger doses. Hence, once we have reached the end of a conventional course of ATD treatment (12 - 18 months), the hazard is eliminated, and adverse events are very rare to occur. Therefore, by continuing low-dose ATD, we could safely maintain the patient’s euthyroid status. Conclusions: Long-term ATD treatment is safe, especially at a low dose. It can be considered as the preferred treatment for selected hyperthyroid patients.

We studied whether a patient with Graves' disease will go into remission during antithyroid drug (ATD) treatment. Remission of Graves' hyperthyroidism is predicted by a smooth decrease in TSH receptor antibody (TRAb) during ATD treatment. Cytotoxic T cell lymphocyte-associated molecule-4 (CTLA-4) may play an important role in the development of Graves' hyperthyroidism and in its remission. We studied A/G polymorphism at position 49 in exon 1 of the CTLA-4 gene in 144 Japanese Graves' patients. We intended to reveal the possible association of CTLA-4 gene polymorphism with the remission of Graves' hyperthyroidism. All patients with Graves' disease were treated with ATD. Thyroid-stimulating antibody and TSH binding inhibitory Ig were measured as TRAb. We analyzed CTLA-4 genotypes and alleles with PCR. We calculated the frequencies of CTLA-4 genotypes and alleles. A significant increase in the frequency of the G allele was seen in Graves' patients compared with controls (P = 0.0095). Graves' patients were divided into three groups (A, B, and C) according to time of TRAb disappearance after the start of ATD treatment. In group A patients TRAb had disappeared within 1 yr after the start of ATD treatment, in group B TRAb had disappeared between the beginning of the second year and the end of the fifth year of treatment, and in group C TRAb continued to be positive after 5 yr of ATD treatment. The frequencies of the GG genotype and the G allele were significantly higher in group C patients with persistently positive TRAb over 5 yr of ATD treatment than in the other groups (P < 0.0001). Group C patients did not have the AA genotype. The periods of time until remission were significantly shorter in the AA genotype. Graves' patients with the G allele need to continue ATD treatment for longer periods.

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. 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. 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. 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.

Hyperthyroid patients exhibit accelerated bone loss by increased bone turnover, and normalization of thyroid function is associated with a significant attenuation of increased bone turnover, followed by an increase in bone mineral density. However, of patients with Graves' disease (GD) maintained on antithyroid drug (ATD) treatment, some exhibit persistent suppression of TSH long after normalization of their serum free T3 (FT3) and free T4 (FT4) levels. The aim of this study was to examine whether bone metabolism is still enhanced in TSH-suppressed premenopausal GD patients with normal FT3 and FT4 levels after ATD therapy (n = 19) compared with that in TSH-normal premenopausal GD patients (n = 30), and to evaluate the relationship between serum TSH receptor antibody (TRAb), an indicator of disease activity of GD, and various biochemical markers of bone metabolism. No difference was found between the two groups in serum Ca, phosphorus, or intact PTH, or in urinary Ca excretion. Serum bone alkaline phosphatase (B-ALP), bone formation markers, and urinary excretions of pyridinoline (U-PYD) and deoxypyridinoline (U-DPD), which are bone resorption markers, were significantly higher in the TSH-suppression group than in the TSH-normal group (B-ALP, P < 0.05; U-PYD, P < 0.001; U-DPD, P < 0.001). For the group of all GD patients enrolled in this study, TSH, but neither FT3 nor FT4, exhibited a significant negative correlation with B-ALP (r = -0.300; P < 0.05), U-PYD (r = -0.389; P < 0.05), and U-DPD (r = -0.446; P < 0.05), whereas TRAb exhibited a highly positive and significant correlation with B-ALP (r = 0.566; P < 0.0001), U-PYD (r = 0.491; P < 0.001), and U-DPD (r = 0.549; P < 0.0001). Even in GD patients with normal TSH, serum TRAb was positively correlated with B-ALP (r = 0.638; P < 0.001), U-PYD (r = 0.638; P < 0.001), and U-DPD (r = 0.641; P < 0.001). In conclusion, it is important to achieve normal TSH levels during ATD therapy to normalize bone turnover. TRAb was not only a useful marker for GD activity, but was also a very sensitive marker for bone metabolism in GD patients during ATD treatment.

To evaluate the relationship between severity of Graves' ophthalmopathy (GO) and relapse/remission rate of associated thyroid disease. One hundred and fifty-eight patients with Graves' disease (GD) were seen within the first 6-12 months after the onset of GO and were followed for at least 18 months. During treatment, GO was classified as mild (n = 65) or severe course (n = 93) by severity and activity scores. All patients received standard anti-thyroid drug (ATD) treatment for 1 year, and in cases of relapse another cycle of ATD, thyroidectomy or radioiodine therapy. Following ATD treatment, 27 patients (42%) with a mild course of GO went into thyroid disease remission, while only seven (8%) patients with a severe course of GO achieved remission (P < 0.0001). Eventually, 32 patients (49%) with a mild course needed definitive thyroid therapy and the remaining 9% preferred another cycle of ATD. However, among patients with a severe GO course, 84% needed definitive therapy (P < 0.0001) and 8% opted for another course of ATD treatment. The probability of relapse could also be predicted by TBII levels 12 months after initiation of ATD therapy, as 96.8% of patients with TBII levels above 7.5 IU/l relapsed (odds ratio 24.3). Patients with severe GO and high TBII are unlikely to go into remission. This allows early decision-making regarding definitive treatment of the thyroid in GD patients with severe GO or very high TBII levels.

Graves' disease (GD) accounts for 10%-15% of thyroid disorders in children and adolescents. The use of antithyroid drugs as the initial treatment option in GD is well accepted. An average two years remission is achieved in about 30% of children treated with antithyroid drugs. However, the optimal treatment duration and the predictive marker of remission after antithyroid drug therapy are still controversial. Additionally, 131I therapy and surgery are considered the option for treatment in children and adolescents with GD. We review the treatment options for pediatric GD and the possible determinants of remission and relapse on antithyroid drug treatment in children and adolescents.

Gender Influences the Clinical Presentation and Long-Term Outcome of Graves Disease