The dexamethasone suppression test in demented outpatients with and without depression.

The dexamethasone suppression test (DST) was given to 33 elderly, male outpatients, previously diagnosed by DSM-III criteria as having dementia. Fifteen of these patients also had signs and symptoms of depression and, except for the presence of organic mental syndrome, would have met DSM-III criteria for major depressive episode. Of these 15 depressed, demented patients, 40% had abnormal DST results. None of the 18 patients who had dementia alone had abnormal DSTs. Our data suggest that in elderly, demented outpatients, an abnormal DST may be associated with concomitant depression.