The mechanism for a blunted thyroid stimulating hormone (TSH) response
to thyrotropin releasing hormone (TRH) in alcoholics is not known. We
performed a combined TRH and gonadoliberin stimulation test on three
well-defined groups of nondepressed alcoholic men. Group A comprised p
atients with acute withdrawal symptoms (n = 28), group B patients abst
inent for 5-8 weeks (n = 29) and group C patients who had been abstine
nt for >2 years (n = 16). Twenty-two healthy male volunteers were used
for comparison. A blunted TSH response to TRH (delta TSH < 5 mu U/1)
occurred only in groups A (39%) and B (17%). In group A delta TSH show
ed a significant negative correlation with the severity of withdrawal
symptoms and a significant positive correlation with serum magnesium l
evels. In group B, patients with a family history of alcoholism had si
gnificantly lower delta TSH levels than those without such a family hi
story. Groups did not differ with respect to basal and delta prolactin
, and TSH responses were not significantly associated with vitamin def
iciency, cortisol levels or free thyroid hormone levels. We conclude t
hat TRH stimulation test blunting appears to be related to factors ope
rating in the withdrawal state and improves with continued abstinence.
A possible role of genetic factors and serum magnesium needs to be fu
rther explored.