Factors Affecting Timing of Hypothyroidism Following Radioactive Iodine Therapy Patients With Graves Disease

Recruiting

• Conditions: Radioactive Iodine-Induced Hypothyroidism in Graves Disease Patients
• Interventions: Radiation: Radioactive Iodine therapy

• Registration Number: NCT05643365
• Lead Sponsor: Assiut University

Brief Summary

The purpose of this retrospective study was to clarify the possible risk factors of early hypothyroidism after RAI therapy in Graves' disease.

Detailed Description

Hyperthyroidism is a clinical syndrome caused by increased thyroid hormone in the blood, it can lead to multiple complications, including cardiac, hepatic, and hematologic system complications. More than 80% of hyperthyroidism are caused by Graves' disease (GD). 3% of women and 0.5% of men may suffer GD in their lifetime \[1\].

Radioactive iodine (RAI) therapy is an important treatment option for Graves' disease (GD), the main side effect of RAI treatment is hypothyroidism, and the factors resulting in hypothyroidism are still controversial \[2\]. Male gender, smaller thyroid weight, higher thyroid-stimulating hormone, and smaller thyroid volume are Suggested to be the main risk factors for early hypothyroidism \[2\]-\[3\].

Study Timeline

• Study Start: 2013-01-01
• Primary Completion: 2022-11-01
• Study First Submitted: 2022-11-25
• Study First Submitted QC: 2022-12-07
• Study First Posted: 2022-12-08
• Status Verified: 2023-10
• Last Update Submitted: 2023-10-10
• Last Update Posted: 2023-10-12
• Study Completion: 2023-12-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 300

Inclusion Criteria

1. Graves' disease patients after one year of RAI therapy .
2. Suppressed serum thyrotropin (TSH) <0.55 µU/ml , elevated serum free triiodothyronine (FT3) > 6.5 pmol/L , free thyroxin FT4 >22.7 pmol/L .

Exclusion Criteria

1. Patients with other causes of hyperthyroidism , such as toxic multinodular goiter and single toxic adenoma
2. Thyroid cancer
3. Recurrent GD
4. Previous Thyroid surgery
5. Patients can't complete the follow -up within 6 months.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Euthyroidism	Radioactive Iodine therapy	normal hormone levels (FT3 3.5 to 6.5 pmol/L, FT4 11.5 to 22.7 pmol/L, TSH 0.55 to 4.78 μU/mL), and no symptoms of hyperthyroidism after 6 months' follow-up
Hyperthyroidism	Radioactive Iodine therapy	increased hormone levels (FT3 \> 6.5 pmol/L, FT4 \> 22.7 pmol/L, TSH \< 0.55 μU/mL) and symptoms of hyperthyroidism after 6 months' follow-up
Hypothyroidism	Radioactive Iodine therapy	decreased hormone levels (FT3 \< 3.5 pmol/L, FT4 \< 11.5 pmol/L, TSH \> 4.78 μU/mL) and symptoms of hypothyroidism within 6 months' follow-up.

Primary Outcome Measures

Name	Time	Method
predictive factors of early hypothyroidism after RAI therapy	1 year	Retrospective study from 2013 to 2022 to analyze the correlation between clinical, demographic\& and laboratory data and incidence of hypothyroidism by measuring thyroid function tests

Secondary Outcome Measures

Name	Time	Method
the incidence of hypothyroidism within 1 year	10 years	To detect the frequency of hypothyroidism after RAI and when it is most likely occur after 6 months or one year

Trial Locations

Locations (1)

Nuclear medicine unit, department of clinical oncology and nuclear medicine, Assiut university hospital; 🇪🇬 Assiut, Egypt