Comparison of Different Doses of 131I in Severe Graves' Hyperthyroidism
- Conditions
- Graves Disease
- Interventions
- Radiation: Radioiodine
- Registration Number
- NCT01039818
- Lead Sponsor
- Hospital de Clinicas de Porto Alegre
- Brief Summary
The purpose of this study is to determine whether higher doses of radioiodine increase treatment efficacy in severe Graves' disease.
- Detailed Description
Graves' disease (GD) is the most frequent cause of hyperthyroidism, affecting mainly women aged 40-60 years. Radioiodine (¹³¹I), introduced in 1941, has become a cornerstone in the treatment of GD hyperthyroidism. Because of its safety, low costs and rapid effect, it is considered a first line therapy in the United States. However, treatment failure occurs in about 15-25% of patients treated with radioiodine. Patients not cured with the first dose of radioiodine usually present severe hyperthyroidism, characterized by large goiter, high 24-hour radioiodine uptake (24h-RAIU) and very high levels of thyroid hormones. We have previously shown that large goiter (≥48ml) is an independent predictor of treatment failure. In these patients, the therapeutic failure was 40.0% while in patients with smaller goiter was only 6.5% (P=0.005; unpublished). It is generally accepted that higher doses of radioiodine improves cure rates. Indeed, a recent meta-analysis found a correlation between radioiodine dose and therapeutic success in GD patients. To our knowledge, there are no published studies evaluating cure rates with different radioiodine doses in severe GD.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 30
- Consecutive patients with a recent diagnosis of Graves' disease and goiter ≥ 48 ml, attending the Endocrine Division at Hospital de Clinicas de Porto Alegre are eligible.
- Patients with previous treatment with radioiodine or thyroidectomy,
- Signs of moderate or severe ophthalmopathy (proptosis > 22 mm, ophthalmoplegia, chemosis, or lagophthalmos),
- Severe heart disease (symptomatic coronary heart disease, class III heart failure, New York Heart Association criteria),
- Debilitating conditions, and
- Large and compressive goiters (> 150 g).
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Radiodine-200µCi Radioiodine A subgroup of patients with Graves' Disease and goiter ≥48ml treated with 200µCi of ¹³¹I/ml thyroid tissue, corrected by 24h-RAIU, from a randomized controlled trial run at our institution between February 1997 and March 2000, serves as a historical control. Radiodine-250µCi Radioiodine Patients with Graves' Disease and goiter ≥48ml, prospectively assigned to receive 250 µCi of ¹³¹I/ml thyroid tissue, corrected by 24h-RAIU.
- Primary Outcome Measures
Name Time Method Cure, defined as euthyroidism or permanent hypothyroidism based on FT4 measurements. 12 months
- Secondary Outcome Measures
Name Time Method Permanent hypothyroidism 12 months Euthyroidism 12 months
Trial Locations
- Locations (1)
Thyroid Unit, Endocrine Division, Hospital de Clínicas de Porto Alegre
🇧🇷Porto Alegre, RS, Brazil