Circadian patterns of plasma cortisol and testosterone in chronic male alcoholics

Twelve alcoholic men (28-55 yr) presenting hypogonadal features but without overt liver failure were hospitalized and examined still consuming alcohol regularly. Sleep was approximately from 2200 to 0600; three equicaloric meals were served at 0700, 1200, and 1800. Blood samples were drawn at 4-hr intervals throughout a 24-hr span starting from 0800. Measured levels of cortisol and testosterone were then analyzed by rhythmometric procedures in order to estimate parameters of the circadian oscillation such as mesor, amplitude, and acrophase, and the relevant confidence limits. Data were compared to those obtained in a matched group of 20 healthy controls. With regard to cortisol, the rhythmometric analyses allowed the demonstration of a normally synchronized circadian rhythm substantially superimposable in alcoholics and controls. With regard to testosterone, the results were compatible with a significant circadian oscillation only in the control group. Alcoholics did show ample interindividual variability of plasma testosterone levels, but the apparent lack of the circadian rhythm was independent of the steroid concentration. These data extend previous observations and are consistent with the occurrence of important abnormalities in the circadian pattern of plasma testosterone in chronic male alcoholics prior to liver failure.