Depression, negative and positive symptoms, and the DST in schizophrenia

It has been suggested that the presence of depression is a major determinant of abnormal dexamethasone suppression in patients with schizophrenia. It has been reported that negative symptoms in patients with schizophrenia are associated with increased rates of nonsuppression. In this study of schizophrenic inpatients, the Dexamethasone Suppression Test (DST), depression and negative and positive symptom ratings were carried out in two phases of the acute episode, in the second week after administration to, and in the week prior to discharge from, hospital. There was no association between depression and cortisol nonsuppression or between negative and positive symptoms and cortisol nonsuppression either early or late in the acute episode. It is concluded that the DST has no clinical utility in identifying the non-melancholic depression which occurs commonly in schizophrenia.