Selenium treatment in autoimmune thyroiditis: 9-month follow-up with variable doses.
The aim of this study is to investigate the long-term (9 months) effects of variable doses (200/100 microg/day) of L-selenomethionine on autoimmune thyroiditis (AIT) and the parameters affecting the success rate of this therapy. The present study was designed in three steps: (1) 88 female patients with AIT (mean age = 40.1 +/- 13.3 years) were randomized into two groups according to their initial serum TSH, thyroid peroxidase antibody (TPOAb) concentrations, and age. All the patients were receiving L-thyroxine to keep serum TSH <or=2 mIU/l. Group S2 (n = 48, mean TPOAb = 803.9 +/- 483.8 IU/ml) received 200 microg L-selenomethionine per day, orally for 3 months, and group C (n = 40, mean TPOAb = 770.3 +/- 406.2 IU/ml) received placebo. (2) 40 volunteers of group S2 were randomized into two age- and TPOAb-matched groups. Group S22 (n = 20) went on taking L-selenomethionine 200 microg/day, while others (group S21) lowered the dose to 100 microg/day. (3) 12 patients of group S22 (group S222) went on taking L-selenomethionine 200 microg/day, while 12 patients of group S21 (S212) increased the dose to 200 microg/day. Serum titers of TPOAb decreased significantly in group S2 (26.2%, P < 0.001), group S22 (23.7%, P < 0.01) and group S212 (30.3%, P < 0.01). There were no significant changes in group C and group S222 (P > 0.05). TPOAb titers increased significantly in group S21 (38.1%, P < 0.01). A significant decrease in thyroglobulin antibody titers was only noted in group S2 (5.2%, P < 0.01). L-selenomethionine substitution suppresses serum concentrations of TPOAb in patients with AIT, but suppression requires doses higher than 100 microg/day which is sufficient to maximize glutathione peroxidase activities. The suppression rate decreases with time.
Turker
Omer
O
Thyroidology Unit, Department of Nuclear Medicine, GATA Haydarpasa, Istanbul, Turkey. otturker@yahoo.com
Kumanlioglu
Kamil
K
Karapolat
Inanc
I
Dogan
Ismail
I
D000328:Adult; D000704:Analysis of Variance; D000911:Antibodies, Monoclonal / Q000097:blood; D004334:Drug Administration Schedule; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007453:Iodide Peroxidase / Q000276:immunology; D008297:Male; D008875:Middle Aged; D012643:Selenium / Q000008:administration & dosage* / Q000627:therapeutic use; D018709:Statistics, Nonparametric; D013967:Thyroiditis, Autoimmune / Q000097:blood / Q000188:drug therapy*; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
D000911:Antibodies, Monoclonal; D014284:Triiodothyronine; D013972:Thyrotropin; D007453:Iodide Peroxidase; D012643:Selenium; D013974:Thyroxine