Alteration of thyroid hormone economy during alcohol withdrawal in alcoholics

Alcohol and alcohol withdrawal may affect nutritional status in many different ways, including effects on thyroid activity. The influence of alcohol withdrawal on thyroid hormone economy was investigated by measurements of changes in the serum concentrations of thyroxine (T4), 3, 5, 3'-triiodothyronine (T3), 3, 5, 5'-triiodothyronine (reverse T3, rT3), and thyrotropin (TSH) in chronic alcoholics experiencing different degrees of alcohol abstinence. In addition, the serum concentrations of ethanol were measured at entrance. There was no significant correlation between the entrance serum ethanol levels, on the one hand, and those of T4, T3, rT3, or TSH, on the other. However, during severe ethanol abstinence (with or without delirium tremens), there was a significant increase in the serum levels of T4 and rT3, but not in those of T3 and TSH. These findings indicate that (severe) alcohol abstinence can interfere with thyroid hormone economy, either by enhancing thyroid hormone secretion or by reducing T4 and rT3 deiodination. It is an open question whether this represents a beneficial adaptation to the metabolic disturbance caused by alcohol intoxication and abstinence, or an additional derangement that warrants nutritional or other therapeutic measures.