Clinical trial NCT03183752: Insulin Resistance and Metformin Use on Volume of Benign Thyroid Nodules
Official title: The Role of Insulin Resistance and the Effect of Metformin Use on Volume of Benign Thyroid Nodules
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Thyroid Nodule
Insulin Resistance
Keywords: thyroid
insulin
thyroid nodule
insulin resistance
thyroid volume
metformin
Lead sponsor: Hospital Universitário Clementino Fraga Filho
Sponsor class: OTHER
First posted: 2017-06-12
Enrollment: 28
Sex: ALL
Minimum age (years): 18
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: A randomized clinical trial with two groups: to use placebo or Metformine
Primary purpose: TREATMENT

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.

Eligibility criteria: 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

Primary outcomes:
measure: changes in nodule volume from baseline after metformin use
timeFrame: one year
Secondary outcomes:
measure: changes in nodule volume from baseline and changes in homa-ir
timeFrame: one year
measure: changes in TSH levels from baseline after metformin use
timeFrame: one year
Other outcomes:
Locations:
city: Rio de Janeiro
country: Brazil
facility: Patricia Santos
Study officials:
affiliation: UFRJ
name: Patricia Santos, MD
role: PRINCIPAL_INVESTIGATOR
affiliation: UFRJ
name: Patricia Teixeira, PhD
role: STUDY_DIRECTOR
References: