Adrenocortical Dysfunction in Depression: Response to Dexamethasone Suppression Test - a Comparative Study1

Thirty patients of Major Depressive Disorder, Schizophrenia and normal healthy controls each, received an overnight dexamethasone suppression test. Plasma and urinary Cortisol measurements showed that depressed patients had increased adrenocortical activity before dexamethasone and they showed an abnormal early escape from suppression which had a relationship with severity of depression. An attempt has been made to differentiate depressives from schizophrenics by abnormally high Cortisol values. Post-dexamethasone urinary Cortisol as well as combined urinary Cortisol and plasma Cortisol abnormal values gave the best pointers of differentiation. A nonsignificant trend of higher values was observed in bipolar and retarded depressives. Schizophrenics did not differ from normals at any stage.