Thyroid Replacement Therapy in Patients With Subclinical Hypothyroidism

Study Overview
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Brief Summary
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The purpose of this experiment is to compared the changes of thyroid function, anti-thyroid peroxidase antibody, anti-thyroglobulin antibody, thyroid magnetic resonance T1-mapping and various metabolic indexes from baseline to the end of treatment (after the thyroid function had been normal for more than three months)

Detailed Description
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In patients with autoimmune thyroiditis with mild subclinical hypothyroidism, the study period will include a screening period of not more than 30 days, and a 12-week treatment period compared to baseline. At completion of treatment, Thyroid Stimulating Hormone(TSH), free thyroxine (FT4)，free thyroxine (FT3) will be included. The changes of anti-thyroglobulin antibody, anti-thyroglobulin antibody, T1-mapping and metabolic indexes.

Official Title
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Effect of Thyroid Replacement Therapy on Thyroid Structure in Patients With Subclinical Hypothyroidism

Conditions
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Subclinical Hypothyroidisms

Intervention / Treatment
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* Drug: Levothyroxine Sodium Tablets


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Men or women between the ages of 18 and 75; Diagnostic criteria for mild subclinical hypothyroidism :TSH>10mIU/L, thyroxine and free thyroxine levels were normal Positive thyroglobulin antibody and/or Thyroperoxidase antibody No previous use of drugs affecting thyroid function Exclusion Criteria: The contraindications indicated in the Chinese instructions of the drug Liver function impairment Renal function impairment Claustrophobia Mental disorders

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: levothyroxine sodium<br>levothyroxine sodium | Drug: Levothyroxine Sodium Tablets<br>* Levothyroxine Sodium(50ug/Tablets,dosage form 25ug,once a day) was administered to patients with autoimmune thyroiditis with mild subclinical hypothyroidism,<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Thyroid Stimulating Hormone changes | Thyroid Stimulating Hormone Changes from baseline and 12 weeks during follow-up | Thyroid Stimulating Hormone Changes from baseline and 12 weeks during follow-up | 
| free thyroxine changes | free thyroxine changes from baseline and 12 weeks during follow-up | free thyroxine changes from baseline and 12 weeks during follow-up | 
| T1-mapping values of Thyroid MRI | T1-mapping values of Thyroid MRI Changes from baseline and 12 weeks during follow-up | T1-mapping values of Thyroid MRI Changes from baseline and 12 weeks during follow-up | 
| Free triiodothyronine changes | Free triiodothyronine changes Changes from baseline and 12 weeks during follow-up | Free triiodothyronine changes Changes from baseline and 12 weeks during follow-up | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| anti-thyroid peroxidase antibody changes | anti-thyroid peroxidase antibody changes from baseline and 12 weeks during follow-up | anti-thyroid peroxidase antibody changes from baseline and 12 weeks during follow-up | 
| anti-thyroglobulin antibody changes | anti-thyroglobulin antibody changes from baseline and 12 weeks during follow-up | anti-thyroglobulin antibody changes from baseline and 12 weeks during follow-up |