Selenium treatment in autoimmune thyroiditis: 9-month follow-up with variable doses.

Area of Science:

• Endocrinology
• Immunology
• Nutritional Science

Background:

• Autoimmune thyroiditis (AIT) is an endocrine disorder characterized by immune system attack on the thyroid gland.
• Thyroid peroxidase antibodies (TPOAb) are key biomarkers in AIT, indicating thyroid damage.
• L-selenomethionine is a form of selenium, an essential trace element with antioxidant properties.

Purpose of the Study:

• To investigate the long-term effects of varying L-selenomethionine doses on AIT.
• To determine the optimal dosage of L-selenomethionine for suppressing TPOAb levels.
• To identify factors influencing the success rate of L-selenomethionine therapy in AIT patients.

Main Methods:

• A randomized controlled trial involving 88 female patients with AIT, all receiving L-thyroxine therapy.
• Patients were assigned to groups receiving either L-selenomethionine (200 microg/day) or placebo for 3 months.
• Subsequent phases involved dose adjustments (100 microg/day or 200 microg/day) and extended treatment durations for some participants.

Main Results:

• Significant reductions in TPOAb titers were observed with 200 microg/day L-selenomethionine (26.2% decrease).
• Doses of 100 microg/day led to a significant increase in TPOAb titers (38.1% increase).
• A significant decrease in thyroglobulin antibody titers was noted only in the group receiving 200 microg/day.

Conclusions:

• L-selenomethionine effectively suppresses serum TPOAb concentrations in AIT patients.
• Doses higher than 100 microg/day are required for significant TPOAb suppression.
• The suppressive effect of L-selenomethionine on TPOAb may diminish over extended periods.