Effects of Alzheimer's disease and gender on the hypothalamic-pituitary-adrenal axis response to lumbar puncture stress

Differences in hypothalamic-pituitary-adrenal (HPA) axis responsiveness to lumbar puncture (LP) stress were studied in normal elderly subjects and Alz heimers disease (AD) patients of both genders. Elderly normal subjects had larger peak cortisol and ACTH responses than AD patients. These results con trast with some previous reports of increased HPA-axis responsivity associa ted with AD and suggest that AD-related changes in HPA responsiveness depen d on the type of stressor involved and are mediated 'upstream' to the final common pathway to ACTH secretion. HPA-axis responsiveness also differed by gender, with higher peaks and prolonged elevations in elderly female subje cts than in elderly males. (C) 1999 Elsevier Science Ltd. All rights reserv ed.