Suppression of thyroid function by interferon-alpha 2 in man.
Profound biological changes occur in patients treated with interferon. Observations of endocrine changes prompted us to examine the effects of subcutaneous alpha-interferon administration in single doses on circulating levels of thyroid stimulating hormone, total thyroxine, and total triiodothyronine in 10 volunteers (5 healthy subjects and 5 patients with hepatitis C). Blood samples were taken on an out-patient basis immediately before and 2, 12, 24, 48, and 72 h after administration of 1, 3, or 5 x 10(6) units of recombinant alpha-interferon. Application of the different dose levels was randomly assigned. Plasma samples were stored at -80 degrees C; after collection of samples had been completed hormone levels were measured using commercially available test kits. At all time points before and after injection of alpha-interferon, standard deviations of measured hormone levels of healthy control subjects and patients overlapped to a considerable extent. At a dose level of 5 x 10(6) units, alpha-interferon significantly increased cortisol levels as described, and decreased the level of thyroid stimulating hormone in the group receiving alpha-interferon as compared to placebo-treated healthy volunteers. The effects occurred 12 h after injection. Maximum suppression of thyroid stimulating hormone levels was observed 24 h after injection, when serum levels of thyroxine and triiodothyronine also were significantly reduced. We conclude that subcutaneous alpha-interferon treatment with doses as low as 5 x 10(6) units affects the control of thyroid function.
Wiedermann
C J
CJ
Department of Internal Medicine, University of Innsbruck, Austria.
Vogel
W
W
Tilg
H
H
Wiedermann
F J
FJ
Herold
M
M
Zilian
U
U
Wohlfarter
T
T
Gruber
M
M
Braunsteiner
H
H
D000328:Adult; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007370:Interferon Type I / Q000494:pharmacology*; D016898:Interferon-alpha / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D011994:Recombinant Proteins; D013963:Thyroid Hormones / Q000097:blood*; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000032:analysis / Q000097:blood; D014284:Triiodothyronine / Q000097:blood*
D007370:Interferon Type I; D016898:Interferon-alpha; D011994:Recombinant Proteins; D013963:Thyroid Hormones; D014284:Triiodothyronine; D013972:Thyrotropin; D013974:Thyroxine; D006854:Hydrocortisone