Dexamethasone suppression test in depression.

Baseline plasma Cortisol levels and response to dexamethasone in a group of twenty five patients with ma) or depressive disorder (MDD) and a control group of twenty five patients with psychiatric diagnoses other than MDD were estimated. The results of our study show that dexamethasone suppression test (DST) is a useful diagnostic aid in MDD with melancholia with a sensitivity of 46% and specificity of 96%. Nonsuppression to DST is a marker of the state of melancholia and is not influenced by any other demographic or clinical variable. In our study 4 p.m. sample alone identified all the DST positive patients. MDD with melancholia showed significantly higher percentage of Cottisol hypersecretion and all non-suppressors were hypersecretors.