Normalization of dexamethasone suppression test: a laboratory index of recovery from endogenous depression

Carroll et al. reported that an abnormal dexamethasone suppression test (DST) may identify approximately 50% of endogenous depressives and that normalization of the test occurs with clinical recovery. Brown et al. and Schlesser et al. have confirmed the diagnostic utility of the test. A preliminary study suggested that when the DST failed to normalize at discharge, patients were at high risk for early relapse. In this study, we compared ten unipolar or bipolar endogenous depressives who had an abnormal DST on admission and a normal DST at discharge, with four patients whose abnormal DST on admission failed to convert at discharge. On all measures, those whose DST fail to convert showed substantially less improvement. Patients whose DST fail to normalize may have incomplete resolution of their underlying depressive process. Despite clinical judgment that discharge may be appropriate these patients may require further active treatment. Use of the DST prior to discharge may help discriminate between patients whose remaining symptoms reflect situational or psychosocial problems and those with a continuing endogenomorphic process.