Cortisol and Alzheimer's disease, II: Dexamethasone suppression, dementia severity, and affective symptoms.

The course of Alzheimer's disease can be complicated by depressive illness, often presenting enigmatically. To determine whether the dexamethasone suppression test (DST) can help distinguish patients with coexisting dementia and depression from those with dementia alone, DSTs were conducted with 22 nondepressed Alzheimer's disease patients. Eleven patients were nonsuppressors. The nonsuppressors were older than the suppressors but did not differ in depression or dementia ratings. The 8:00 a.m. postdexamethasone cortisol level correlated with depressive symptoms. A relationship between severity of dementia and depressive symptoms was also demonstrated.