Results of dexamethasone suppression test in early Alzheimer dementia.

The frequency of an abnormal response to the Dexamethasone Suppression Test (DST) was examined in 24 non-depressed patients in the early stages of Alzheimer dementia. Results were compared with those obtained in 51 geriatric medical inpatients: 15 with major depression, 18 with dysthymic disorder and 18 normal controls. As an abnormal lack of suppression was found in 9 demented patients, in 9 with major depression, 1 with dysthymic disorder and in 2 the normal controls, it appears that DST alone is not useful in distinguishing dementia, even in its early stages, from major depression. In our experience abnormal DST results in demented patients were unrelated to mood.