Effects of 12 months treatment with L-selenomethionine on serum anti-TPO Levels in Patients with Hashimoto's thyroiditis.

OBJECTIVE: We studied the effects of selenium (Se) treatment on serum anti-thyroid peroxidase (TPO) levels in Greek patients with Hashimoto's thyroiditis (HT). DESIGN: We prospectively studied 80 women with HT, median age 37 (range 24-52) years, for 1 year. All patients received 200 microg Se in the form of l-selenomethionine orally for 6 months. At the end of the 6-month period, 40 patients continued taking 200 microg Se (Group A) and 40 patients stopped (Group B). Serum thyrotropin (TSH), free triiodothyronine (FT(3)), free thyroxine (FT(4)), anti-TPO, and anti-thyroglobulin (Tg) levels were measured at baseline and at the end of each 3-month period. MAIN OUTCOME: There was a significant reduction of serum anti-TPO levels during the first 6 months (by 5.6% and 9.9% at 3 and 6 months, respectively). An overall reduction of 21% (p < 0.0001) compared with the basal values was noted in Group A. In Group B, serum anti-TPO levels were increased by 4.8% (p < 0.0001) during the second 6-month period. CONCLUSIONS: Our study showed that in HT patients 6 months of Se treatment caused a significant decrease in serum anti-TPO levels, which was more profound in the second trimester. The extension of Se supplementation for 6 more months resulted in an additional 8% decrease, while the cessation caused a 4.8% increase, in the anti-TPO concentrations.

Changes of bone mineral density in pre-menopausal women with differentiated thyroid cancer receiving L-thyroxine suppressive therapy.

OBJECTIVE: We studied the effect of levothyroxine (L-T(4)) suppressive therapy on bone mineral density (BMD) in pre-menopausal women with total thyroidectomy and radioactive iodine ((131)I) ablation therapy post-operatively for differentiated thyroid cancer (DTC). PATIENTS AND METHODS: We prospectively studied 26 athyroid pre-menopausal women (median age 39 years, range 28-48 years) receiving suppressive L-T(4) therapy postoperatively for 48 months. BMD was measured by dual energy X-ray absorptiometry (DEXA) at the femoral neck, femoral trochanter and Ward's triangle, before (basal) and during (12th and 48th month) the follow-up period. None of the women gave a medical history that could possibly affect bone metabolism. Patients were free of thyroid cancer in clinical and laboratory examinations at the time of the study. Paired t-test was used for comparisons among BMD measurements during the suppressive therapy. RESULTS: There were statistically significant decreases of BMD at all measured regions during (12th and 48th month) L-T(4) suppressive therapy. The overall decreases in BMD at the femoral neck, femoral trochanter and Ward's triangle were 7.5%, 10.9% and 3.4%, respectively, at the end of the follow-up period. The coefficient of variation (CV) of all BMD measurements was around 10%, showing a rather homogenous group of patients. Our patients had a statistically significant decrease in their body mass index (BMI) and weight at the end of the follow-up period. However, there was no significant correlation between the decrease in BMI and BMD. Patients did not experience significant adverse effects from L-T(4) suppressive therapy during the study. CONCLUSION: L-T(4) suppressive therapy for at least 1 year in pre-menopausal women with DTC causes a reduction in BMD of the femoral neck, femoral trochanter and Ward's triangle.