The dexamethasone suppression test and suicidal patients.

The dexamethasone suppression test (DST) was used in an in-patient crisis unit to determine whether the test could identify suicidal patients who might benefit from tricyclic antidepressants. DST results, DSM-III diagnoses, and measures of symptom levels were obtained for 72 patients admitted for a 3-5 day period; 31 were non-suppressors. Abnormal DST results were not related to DSM-III diagnosis or to scores on measures of depression and symptom levels. Only three patients met DSM-III criteria for major depression with melancholia; 26 patients had a diagnosis of alcohol or substance abuse. The poor specificity of the DST in this patient population suggests that its routine use in such patients could be highly misleading.