Evaluation of depression in a general hospital: utility and limitations of the dexamethasone suppression test.

Use of the DST was studied in medically hospitalized, depressed patients. Although complicating medical factors necessarily excluded nearly 60% of referrals, post-dexamethasone plasma cortisol values were significantly higher in 14 major depressives appropriate for the DST as compared to 12 patients with milder, subsyndromal depressive conditions. Using a plasma cortisol criterion of greater than 7 micrograms/dl, the DST identified major depression with 57% sensitivity and 92% specificity in this subsample (p less than 0.005). While limited by a high exclusion rate, the DST may be useful for confirmation of major depression in carefully screened general hospital patients. Implications for research and practice are discussed.