[C] How should overt hyperthyroidism due to GD be managed?

[C] How should overt hyperthyroidism due to GD be managed?

  • RECOMMENDATION 4
    Patients with overt Graves' hyperthyroidism should be treated with any of the following modalities: 131I therapy, antithyroid medication, or thyroidectomy. 1/++0

Once it has been established that the patient is hyperthyroid and the cause is GD, the patient and physician must choose between three effective and relatively safe initial treatment options: 131I therapy (radioactive iodine), antithyroid drugs (ATD), or thyroidectomy (44). In the United States, radioactive iodine has been the therapy most preferred by physicians. In Europe and Japan, there has been a greater physician preference for ATDs and/or surgery (45). The long-term quality of life (QoL) following treatment for GD was found to be the same in patients randomly allocated to one of the three treatment options (46).

Technical remarks: Once the diagnosis has been made, the treating physician and patient should discuss each of the treatment options, including the logistics, benefits, expected speed of recovery, drawbacks, potential side effects, and cost. This sets the stage for the physician to make recommendations based on best clinical judgment and allows the final decision to incorporate the personal values and preferences of the patient.

Factors that favor a particular modality as treatment for Graves' hyperthyroidism:

  1. 131I: Females planning a pregnancy in the future (in more than 4–6 months following radioiodine therapy, provided thyroid hormone levels are normal), individuals with comorbidities increasing surgical risk, and patients with previously operated or externally irradiated necks, or lack of access to a high-volume thyroid surgeon or contraindications to ATD use.
  2. ATDs: Patients with high likelihood of remission (patients, especially females, with mild disease, small goiters, and negative or low-titer TRAb); the elderly or others with comorbidities increasing surgical risk or with limited life expectancy; individuals in nursing homes or other care facilities who may have limited longevity and are unable to follow radiation safety regulations; patients with previously operated or irradiated necks; patients with lack of access to a high-volume thyroid surgeon; and patients with moderate to severe active GO.
  3. Surgery: Symptomatic compression or large goiters ( ≥ 80 g); relatively low uptake of radioactive iodine; when thyroid malignancy is documented or suspected (e.g., suspicious or indeterminate cytology); large nonfunctioning, photopenic, or hypofunctioning nodule; coexisting hyperparathyroidism requiring surgery; females planning a pregnancy in <4–6 months (i.e., before thyroid hormone levels would be normal if radioactive iodine were chosen as therapy), especially if TRAb levels are particularly high; and patients with moderate to severe active GO.

Contraindications to a particular modality as treatment for Graves' hyperthyroidism:

  1. 131I therapy: Definite contraindications include pregnancy, lactation, coexisting thyroid cancer, or suspicion of thyroid cancer, individuals unable to comply with radiation safety guidelines and females planning a pregnancy within 4–6 months.
  2. ATDs: Definite contraindications to long-term ATD therapy include previous known major adverse reactions to ATDs.
  3. Surgery: Factors that may mitigate against the choice of surgery include substantial comorbidity such as cardiopulmonary disease, end-stage cancer, or other debilitating disorders. Pregnancy is a relative contraindication and should only be used in this circumstance, when rapid control of hyperthyroidism is required and antithyroid medications cannot be used. Thyroidectomy is best avoided in the first and third trimesters of pregnancy because of teratogenic effects associated with anesthetic agents and increased risk of fetal loss in the first trimester and increased risk of preterm labor in the third. Optimally, thyroidectomy is performed in the latter portion of the second trimester. Although it is the safest time, it is not without risk (4.5%–5.5% risk of preterm labor) (47,48).

Factors that may impact patient preference:

  1. 131I therapy: Patients choosing 131I therapy as treatment for GD would likely place relatively higher value on definitive control of hyperthyroidism, the avoidance of surgery, and the potential side effects of antithyroid medications, as well as a relatively lower value on the need for lifelong thyroid hormone replacement, rapid resolution of hyperthyroidism, and potential worsening or development of GO (49).
  2. ATDs: Patients choosing antithyroid drug therapy as treatment for GD would place relatively higher value on the possibility of remission and the avoidance of lifelong thyroid hormone treatment, the avoidance of surgery, and exposure to radioactivity and a relatively lower value on the avoidance of ATD side effects (see section E), the need for continued monitoring and the possibility of disease recurrence.
  3. Surgery: Patients choosing surgery as treatment for GD would likely place a relatively higher value on prompt and definitive control of hyperthyroidism, avoidance of exposure to radioactivity, and the potential side effects of ATDs and a relatively lower value on potential surgical risks and need for lifelong thyroid hormone replacement.