Chronic alcoholics who had been abstinent from alcohol for more than 2
years were evaluated with the thyrotropin-releasing hormone (TRH) test. The
findings suggest the following profound disturbances in the
hypothalamic-pituitary-thyroid axis: 1) a "euthyroid sick syndrome,"
evidenced by low levels of triiodothyronine (T3), high levels of reverse
T3, and normal levels of thyroxine (T4) (this syndrome implies a decreased
5'-deiodination of T4 to T3 and of reverse T3 to its lesser iodinated
metabolites), 2) an increased binding capacity for thyroid hormones,
evidenced by a decreased T3-uptake value and an increased level of
T4-binding globulin, and 3) thyroid-stimulating hormone (TSH) blunting in
31% of patients. Paradoxically, there was a positive correlation between
basal T4 and delta max TSH in subjects with blunted TSH, but baseline TSH
levels were reduced in subjects with and without blunted TSH.