CSF corticotropin-releasing hormone and somatostatin in major depression: response to antidepressant treatment and relapse.

Immunoreactive corticotropin-releasing hormone (CRH) and somatostatin (SRIF) were measured in the cerebrospinal fluid (CSF) of 24 female in-patients, suffering from DSM-III-R major depression, both before and after antidepressant treatment. In the total group there were no significant differences between pre- and post-treatment CSF-CRH and SRIF concentrations despite satisfactory clinical improvement in each patient. However, there was a significant post-treatment reduction of the CSF-CRH concentration in the 15 patients who remained depression-free for at least 6 months following treatment, in contrast to the tendency for elevation in those 9 subjects who relapsed within 6 months. CSF-SRIF showed no similar pattern. High, or even increasing, CSF-CRH concentration during antidepressant treatment may indicate lack of normalization of an underlying process in major depression despite symptomatic improvement and predicted early relapse.