Insulin Resistance, Thyroid Nodule
Conditions
Keywords
thyroid, insulin, thyroid nodule, insulin resistance, thyroid volume, metformin
Brief summary
It has been shown that insulin might be involved in the pathogenesis of thyroid growth. Objective To evaluate the impact of IR and metformin use on the volume of benign thyroid nodules (TNs). Methods A randomized clinical trial to placebo (P) or MTF use. Previous fine needle aspiration confirming the diagnosis is necessary to inclusion. Patients will receive similar tablets of MTF and placebo and instruct to take 3 tablets/day of MTF (500mg/tablet). Thyroid volume, as TN volume, will be assess by ultrasound, both in the beginning, six months and one year after randomization, by the same researcher blinded regarding location group. Blood samples to measure: TSH, FT4, TPO-Ab, lipid profile, glucose and insulin were done after 8h fasting.
Detailed description
It has been shown that insulin might be involved in the pathogenesis of thyroid growth. Previous studies suggest that metformin (MTF) therapy decreased thyroid volume and nodule size in subjects with insulin resistance (IR). Objectives To evaluate the impact of IR and metformin use on the volume of benign thyroid nodules (TNs). Methods A randomized clinical trial to placebo (P) or MTF use. Previous fine needle aspiration confirming the diagnosis is necessary to inclusion. Exclusion criteria were: nodules with a predominantly cystic pattern, pregnancy, diabetes, acromegaly, previous use of MTF, levothyroxine, corticoid or any weight loss medication in the past six months, hepatic or cardiac insufficiency, creatinine levels \> 1.4 mg/dL and MTF intolerance doses \>1.0 gram/day. Patients will receive similar tablets of MTF and placebo and will be instructed to take 3 tablets/day of MTF (500mg/tablet). Thyroid volume, as TN volume, will be accessed by ultrasound, both in the beginning, six months and one year after randomization, by the same researcher blinded regarding location group. Blood samples to measure: TSH, FT4, TPO-Ab, lipid profile, glucose and insulin were done after 8h fasting.
Interventions
DRUGMetformin
500 mg metformin three times daily
DRUGPlacebo
500 mg placebo three times daily
Sponsors
Hospital Universitário Clementino Fraga Filho
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)
Masking description
The same researcher blinded regarding location group will access thyroid volume and thyroid nodule volume by ultrasound, in the beginning, six months and one year after randomization
Intervention model description
A randomized clinical trial with two groups: to use placebo or Metformine
Eligibility
Sex/Gender
ALL
Age
18 Years to 80 Years
Healthy volunteers
Yes
Inclusion criteria
* patients with benign nodules diagnosed by fine needle aspiration biopsy (FNAB)
Exclusion criteria
* Nodules with a predominantly cystic pattern * Eggshell calcification * Coalescent thyroid nodules (not suitable for size analysis) * Pregnancy * Diabetes * Acromegaly * Previous use of MTF, levothyroxine, corticoid or any weight loss medication in the past six months * Hepatic or cardiac insufficiency * Creatinine levels \> 1.4 mg/dL * MTF intolerance doses \< 1.0 gram/day
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| changes in nodule volume from baseline after metformin use | one year | the impact of metformin on the volume of thyroid nodules |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| changes in nodule volume from baseline and changes in homa-ir | one year | the impact of insulin resistance in volume of thyroid nodules |
| changes in TSH levels from baseline after metformin use | one year | the impact of metformin use in TSH levels |
Countries
Brazil
Outcome results
None listed