Levothyroxine Treatment in Thyroid Benign Nodular Goiter

Study Overview
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Brief Summary
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We will study the effect of taking eltroxin at different time, i.e. fasting or postprandial periods. We will also study the effect of levothyroxin treatment in Chinese people

Detailed Description
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OBJECTIVE - Current treatment of benign thyroid is oral levothyroxin by suppression of thyrotropin secretion and so that tumor growth. Although current consensus is taking thyroxin one hour before meal because the PH value of gastrointestinal tract will affect drug absorption, some patient suffered from epigastric discomfort when taking thyroxin with empty stomach, and wish to take it postprandial. However, there is no direct evidence showing if taking thyroxin at different time point significantly affects treatment outcome. Besides, the response to thyroxin therapy differs among people. The purposes of this study are to evaluate the clinical significance of different time points of thyroxine intake and to search factors relating to thyroxin response of benign thyroid tumors. RESEARCH DESIGN AND METHODS - We will include patients who have benign thyroid tumors diagnosed with fine needle aspiration cytology and have normal thyroid function into our study. After informed consent, patients will be randomly assigned into two groups. Patients in the first group will take thyroxin one hour before breakfast until thyrotropin level stabilized between 0.5 and 1.0 mU/L for 3 months. Then thyroxin will be discontinued. Patients will restart thyroxin therapy three months later but after breakfast. Patients in another group will take thyroxin postprandial, discontinue thyroxin and then one hour before breakfast. Questionnaire interviews about diet and life style, blood samples and fine needle aspiration cytology samples will be obtained. Changes of thyroid nodules will be evaluated with thyroid echo. STATISTIC ANALYSIS - Descriptive data will be described as means and SDs for continuous variables, and analysis of variance and Chi-square tests were used for assessing the significances. A p-value below 0.05 was considered significant. Keywords: benign thyroid tumor, thyroxin, preprandial, postprandial.

Official Title
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Levothyroxine Treatment in Thyroid Benign Nodular Goiter

Conditions
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Thyroid Nodule

Intervention / Treatment
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* Drug: Levothyroxin treatment


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age between 20 to 90 years old Benign nodular goiter diagnosed with thyroid echo and fine-needle - aspiration cytology Exclusion Criteria: Age younger than 20 or older than 90 years old Pregnancy Allergy to eltroxin Taking other drugs which will have drug interaction with eltroxin patients with cardiovascular disease, hypertension, gastrointestinal disease

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 90 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
Allocation: Non-Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 1<br>under eltroxin | Drug: Levothyroxin treatment<br>* Levothyroxin 100 micogram will be administered once daily 1 hour before meal of just after meal for 3 months, and the dose will be titrate to keep serum TSH level between 0.1 0.3 mU/L. It will be discontinued for 3 months. Then<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The size of thyroid nodules |  | 3 months after levothyroxine treatment |