The prognostic value of thyroid-stimulating immunoglobulin in the management of Graves' disease

Effects of Low-dose Methotrexate With Methimazole in Patients With Graves' Disease: Results of a Randomized Clinical Trial

CONTEXT

Supplemental methotrexate (MTX) may affect the clinical course of Graves' disease (GD).

OBJECTIVE

To evaluate the efficacy of add-on MTX on medical treatment in GD.

DESIGN

Prospective, open-label, randomized supplementation controlled trial.

SETTING

Academic endocrine outpatient clinic.

PATIENTS

One hundred fifty-three untreated hyperthyroid patients with GD.

INTERVENTION

Patients received MTX 10 mg/w with methimazole (MMI) or MMI only. MTX and MMI were discontinued at months 12 to 18 in euthyroid patients.

MAIN OUTCOME MEASURES

Discontinuation rate at month 18 in each group.

RESULTS

In the MTX with MMI group, the discontinuation rate was higher than the MMI group at months 15 to 18 [50.0 vs 33.3%, P = .043, 95% confidence interval (CI) 1.020-3.922; and 55.6 vs 38.9%, P = .045, 95% CI 1.011-3.815, respectively). The decrease in thyrotropin-related antibodies (TRAb) levels in the MTX with MMI group was significant from baseline to month 6 compared to the MMI alone group [MTX + MMI 67.22% (43.12-80.32), MMI 54.85% (33.18-73.76), P = .039] and became more significant from month 9 [MTX + MMI 77.79% (62.27-88.18), MMI 69.55% (50.50-83.22), P = .035] to month 18 (P < .01 in 15-18 months). A statistically significant difference was seen between the levels of TRAb in the MTX with MMI group and the MMI group at 9 to 18 months. There were no significant differences in the levels of free T3, free T4, and TSH between the 2 groups. No serious drug-related adverse events were observed in either group (P = .771).

CONCLUSION

Supplemental MTX with MMI resulted in a higher discontinuation rate and improvement in decreased TRAb levels to homeostatic levels faster than methimazole treatment alone at months 12 to 18.

A Predictive Model for Graves' Disease Recurrence After Antithyroid Drug Therapy: A Retrospective Multicenter Cohort Study

OBJECTIVES

Predicting recurrence after antithyroid drug (ATD) cessation is crucial for optimal treatment decision-making in patients with Graves' disease (GD). We aimed to identify factors associated with GD recurrence and to develop a model using routine pretherapeutic clinical parameters to predict GD recurrence risk during the first year following ATD discontinuation.

METHODS

This electronic health records-based observational cohort study analyzed patients with GD treated with ATDs at 3 U.S. academic centers. Demographic, clinical characteristics, and GD recurrence within 1 year following ATD discontinuation were assessed. Univariable and multivariable analyses were performed. A predictive model for GD recurrence was developed and visualized as a nomogram.

RESULTS

Among the 523 patients included in the study, 211 (40.34%) discontinued treatment. Of these, the 142 (67.29%) that had a follow-up period exceeding 12 months after stopping ATD were used for the development of the predictive model. Among the patients included in the model, the majority were women (n = 111, 78.16%), with a mean age of 49.29 years (standard deviation 16.31) and baseline free thyroxine (FT4) levels averaging 3.39 ng/dl (standard deviation 2.25). Additionally, 79 of 211 patients (37.44%) experienced recurrence within 1 year. Multivariable analysis indicated a 31% increased risk of GD recurrence per additional decade of age (odds ratio 1.31, 95% confidence interval 1.03-1.66, P = .0258), and a 65% increased risk of GD recurrence for every 2.0 ng/dL rise in baseline FT4 (odds ratio 1.65, 95% confidence interval 1.08-2.50, P = .0192). The recurrence predictive model's area under the curve was 0.69 in the derivation dataset and 0.65 in cross-validation.

CONCLUSIONS

This study introduced a practical model that can be used during the initial therapeutic decision-making process. It utilizes easily accessible baseline clinical data to predict the likelihood of GD recurrence after 1 year of ATD therapy. Further research is needed to identify other factors affecting risk of recurrence and develop more precise predictive models.

Comparison between thyroid stimulating immunoglobulin and TSH-receptor antibodies in the diagnosis and management of Graves' disease

Introduction

TSH-receptor antibodies (TRAb) directed against the TSH receptor (TSH-R) induce hyperthyroidism in patients with Graves' disease (GD). TRAb detected by previous radioimmunoassay only reflects the presence of autoantibodies, but not the function of such antibodies. Thyroid stimulating immunoglobulins (TSI) is a relatively new method for assessing TSH-receptor antibodies function. The aim of this study was to investigate the role of TSI in the diagnosis and management of GD.

Methods

Patients with newly diagnosed GD (n=140, age 38.00 ± 11.99 years, 106 women) received pharmacological therapy (methimazole) up to 18 months in the outpatient or inpatient department of the Second People's Hospital of Foshan City from January 2013 to December 2018. GD was identified by clinical signs and symptoms and relevant laboratory tests. Blood samples for TSI and TRAb and other thyroidal biomarkers were obtained at baseline and at three times during the follow-up. All patients with GD were followed up for at least 5 years to see if the patient was cured or had relapsed.

Results

TSI and TRAb in GD patients were significantly higher than those in the normal control group (P<0.001), and there was a strong correlation between TSI and TRAb in GD patients (P<0.001). After treatment, TSI and TRAb significantly decreased (P<0.05), TSI and TRAb in patients with disease course more than 2 years were significantly higher than those in patients with disease course less than 2 years (P<0.05), There was no statistically significant difference in TSI and TRAb at initial diagnosis between patients with a disease duration of more than 2 years and less than 5 years and those with a disease duration of more than 5 years (P>0.05); if the patients were still positive for TSI or TRAb antibodies at 5 years of follow-up after treatment with anti-hyperthyroidism medication, the patients were at a higher risk of relapse (P<0.001).

Conclusion

The higher TSI at the initial diagnosis of GD, the longer duration of treatment with anti-hyperthyroid drugs and the higher risk of relapse. Compared with TRAb, serum TSI level is also important in the clinical diagnosis and prognosis of GD, but which one is superior to the other needs further study.

Thyroid stimulating receptor autoantibodies

Thyroid-stimulating hormone receptor autoantibodies (TRAbs) play a crucial role as pathogenic antibodies in both the diagnosis and management of Graves' disease (GD). GD, an autoimmune disease resulting from a combination of genetic and environmental factors, is the most common cause of hyperthyroidism. With advancements in technology for TRAb detection and the availability of automated commercial kits, TRAb has become an essential clinical laboratory marker for the diagnosis of GD, as well as extra-thyroidal manifestations like Graves' ophthalmopathy (GO). This article provides a comprehensive review of TRAb, encompassing its clinical assays along with its significance in the clinical setting.

The prevalence of positive thyroid autoantibodies in patients with subacute thyroiditis: a systematic review and meta-analysis

PURPOSE

Subacute thyroiditis (SAT) is a transient inflammatory disorder of the thyroid gland with a possible viral etiology. We conducted this study to estimate the pooled prevalence of thyroid autoantibodies in SAT patients. This question arose due to the varying reports on the positivity rates of thyroid autoantibodies among SAT patients.

METHODS

We searched PubMed, Embase, Scopus, and Web of Science from their inception until March 25th, 2023. Observational studies reporting the positivity rate of thyroid autoantibodies for more than ten patients were included. We used the Joanna Briggs Institute's (JBI) critical appraisal checklist to assess the quality of the included studies. Pooled prevalence estimates with 95% confidence intervals were calculated using the random effects model. Subgroup analyses were performed to find sources of heterogeneity.

RESULTS

Out of 1373 identified records, 32 studies involving 2348 SAT patients were included in our study. Thyroglobulin antibody (TgAb) and thyroid peroxidase antibody (TPOAb) were positive in 22.8% and 12.2% of patients, respectively. The Study design, mean erythrocyte sedimentation rate and mean thyroid-stimulating hormone of patients were identified as sources of heterogeneity. As our secondary objectives, we found a recurrence rate of 14.7% and permanent hypothyroidism in 11.6% of patients.

CONCLUSION

The results of our study revealed a low TPOAb positivity rate in SAT patients, consistent with its non-autoimmune etiology. The TgAb positivity rate in SAT patients was higher than that of the general population, possibly explained by the transient release of thyroglobulin into the bloodstream during the thyrotoxic phase, leading to subsequent TgAb production. Furthermore, our findings demonstrate a notable recurrence rate and permanent hypothyroidism among SAT patients, highlighting the importance of ongoing follow-up care.

Azathioprine as an adjuvant therapy in severe Graves' disease: a randomized controlled open-label clinical trial

Introduction

Azathioprine (AZA) interferes with the activation of T and B lymphocytes, which are the main cells involved in the pathogenesis of Graves' disease (GD). The aim of this study was to investigate the effectiveness of AZA as an adjuvant therapy to antithyroid drugs (ATDs) for moderate and severe GD. In addition, we conducted an incremental cost-effectiveness analysis of AZA to determine its cost-effectiveness.

Methods

We conducted a randomized, open-label, and parallel-group clinical trial. We randomized untreated hyperthyroid patients with severe GD into three groups. All patients received 45-mg carbimazole (CM) as the starting dose and propranolol 40-120 mg daily. The first group (AZA1) received an additional 1 mg/kg/day AZA, the second group (AZA2) received an additional 2 mg/kg/day AZA, and the third group (control group) received only CM and propranolol. We measured thyroid-stimulating hormone (TSH) and TSH-receptor antibody (TRAb) levels at baseline and every 3 months, while free triiodothyronine (FT3) and free thyroxine (FT4) levels were measured at the time of diagnosis, 1 month after initiation of therapy, and every 3 months thereafter until 2 years after remission. Thyroid volume (TV) was assessed by ultrasound at baseline and 1 year after remission.

Results

A total of 270 patients were included in this trial. By the end of follow-up, there was higher remission rate in the AZA1 and AZA2 groups compared with controls (87.5% and 87.5% vs. 33.4%, p = 0.002). Throughout the course of follow-up, FT3, FT4, TSH, and TRAb were significantly different between the AZA groups and the control group, but there was no significant difference regarding TV. The decline in the concentrations of FT4, FT3, and TRAb was significantly faster in the AZA2 group than in the AZA1 group. The relapse rate during the 12-month follow-up was insignificantly higher in the control group than in either the AZA1 or AZA2 group (10, 4.4, and 4.4%, p = 0.05, respectively). The median relapse time was 18 months for the control group and 24 months for the AZA1 and AZA2 groups. The incremental cost-effectiveness ratio for the AZA group compared with the conventional group was 27,220.4 Egyptian pounds per remission reduction for patients using AZA as an adjuvant for ATDs.

Conclusion

AZA could be a novel, affordable, cost-effective, and safe drug offering hope for patients with GD to achieve early and long-lasting medical remission.

Trial registry

The trial is registered at the Pan African Clinical Trial Registry (Registration number: PACTR201912487382180).