Energy Metabolism in Thyroidectomized Patients

In this study, Levothyroxine (LT4) and placebo (a look-alike inactive substance, a "sugar pill") will be compared to Liothyronine/ Levothyroxine (LT3/LT4) combination therapy.

Levothyroxine LT4 and Liothyronine (LT3) are drugs approved by the U. S. Food and Drug Administration (FDA).

All participants will be required follow VCU Health COVID-19 standard of Care screening procedures.

This study requires approximately five study visits The five-study visits required will be a Screening Visit (outpatient), one Baseline Visit, (inpatient) one Six Week Visit, (outpatient), one Three Month Visit and one Six Month Visit (both inpatient). A COVID-19 test will be done 48 hours (2 days) before each of the three-inpatient visit, Baseline Visit, Three Month and Six Month Visit.

Participants will be asked to:

• Give permission for the researchers to collect information about their medical history from participants and their medical records five times during the study visits and for 5 years after the study visits.
• Have a Physical exam done 5 times
• 24-hour energy expenditure recording in the Whole room indirect calorimeter studies 3 times (inpatient overnight stays: Baseline, Three months, and Six months visits)
• Study drug will be dispensed three times
• Have study drug dose adjustments two times
• Genomic blood draw for DNA one time
• Have blood drawn five times
• Have an DXA Scan two times
• Have an Echocardiogram three times
• Complete questionnaire three times
• Have Accelerometers sensors laced 3 times (inpatient overnight stays: Baseline, Three months, and Six months visits)
• ClearSight (blood pressure monitoring) procedure three times
• Be randomized to take either Levothyroxine LT4 + placebo group or LevothyroxineLT3/Liothyronine LT4 group from baseline through 6 months

Participation in this study will last up to 6 months after surgery. Approximately 30 total individuals will participate in this study

Inclusion criteria

• Clinical indication for total thyroidectomy
• TSH at screening >0.045<4.5mlU/m
• Adult men and women Age ≥18-89 years of age
• Euthyroid patients with clinical indication for total thyroidectomy
• Indication to total thyroidectomy for benign goiter or thyroid cancer not requiring suppressive thyroid hormone therapy

Exclusion criteria

• Weight <50 or >150 Kg
• Graves' disease
• Use of thyroid hormone therapy or thyroid supplements (at screening) except for multinodular goiter
• Indication for thyroid hormone suppressive therapy following surgery
• Uncontrolled arterial hypertension stage 2 or greater (>140/90 mm Hg at screening) while on medication (patients with hypertension controlled by therapy will be allowed to participate).
• Uncontrolled diabetes (HbA1c > 8.% at screening or Fructosamine > 325 mmol/L)
• History of cardiovascular disease, congestive heart failure or unstable coronary artery disease (angina, coronary event, or revascularization within 6 months); atrial fibrillation; or ventricular arrhythmia,
• History of major depression or psychosis
• Patients who are Pregnant, breastfeeding planned pregnancy within six months from the thyroidectomy
• Any conditions that in the opinion of the PI may impede the successful completion of the study