Comparison of Different Doses of 131I in Severe Graves' Hyperthyroidism

Phase 3

Completed

• Conditions: Graves Disease

• 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 In these patients, the therapeutic failure was 40.0% while in patients with smaller goiter was only 6.5% (P=0.005; unpublished).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.

Study Timeline

• Study Start: 1997-02
• Study First Submitted: 2009-12-24
• Study First Submitted QC: 2009-12-24
• Study First Posted: 2009-12-25
• Primary Completion: 2011-08
• Study Completion: 2011-08
• Status Verified: 2012-09
• Last Update Submitted: 2012-09-04
• Last Update Posted: 2012-09-06

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 30

Inclusion Criteria

• 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.

Exclusion Criteria

• 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

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