Clinical stages of dementia and the dexamethasone suppression test

1. 1. This study vas undertaken to evaluate the relationship between clinical aspects of primary degenerative dementia and suppression or non-suppression in the dexamethasone suppression test. 2. 2. We studied 34 male patients with primary degenerative dementia (as diagnosed by DSM-III criteria). Dexamethasone 1 mg p.o. was administered at 11:00 PM and blood was drawn for cortisol determination at 4:00 PM the next day. 3. 3. Clinical factors included: age, age at onset, duration of dementia, history of psychiatric illness, severity as measured by Global Deterioration Scale (GDS) score, and "malignancy" of dementia (rated by years of onset to institutionalization and as a ratio of Global Deterioration Scale to duration of primary degenerative dementia). 4. 4. Results: 56%. of primary degenerative dementia patients failed to suppress. The highest degree of non-suppression was seen in Global Deterioration Scale 5 and 6 subjects (Table). 5. 5. An unexpected finding was that a large number of Global Deterioration Scale 7 patients demonstrated normal post-dexamethasone suppresion of the hypothalmic-pituitary-adrenal axis. 6. 6. Some contradictions in previously reported studies may be explained by this pattern.