Relationship between plasma cortisol concentrations and depression in chronic alcoholic patients

Plasma cortisol levels were estimated by the competitive protein binding (CPB) method with radioactive selenium-75 in 32 male chronic alcoholics with depression. The degree of depression was rated by the Hamilton Depression Rating Scale (HDRS). Duration of drinking ranged from 5-25 years with an average daily amount of ethanol intake of 100-150 g (equivalent to half a bottle of spirits). Plasma cortisol levels were often raised in drinking chronic alcoholics and there was a strongly positive and statistically highly significant correlation between them and depression ratings (r = +0.56; P = 0.001). It is possible that the diurnal rhythm of cortisol secretion is disturbed or adreno-cortical activity is stimulated in these patients due to chronic ethanol ingestion. It is further suggested that brain serotonin deficiency known to occur in chronic alcoholics might lead to raised plasma cortisol levels in ethanol-induced depression.