Estrogen replacement therapy and Alzheimer's disease

Estrogen replacement therapy (ERT) is increasingly recommended for postmeno pausal women due to its numerous beneficial effects on bone, cardiovascular system, brain function and quality of life. Data from retrospective epidem iological studies have shown that ERT has a potential to reduce the risk fo r developing Alzheimer's disease (AD) and to delay its progression. In addi tion, recent clinical studies have reported improvement of cognitive functi ons in women with AD. Findings from basic science indicated that the possib le mechanisms of action by which estrogen may affect AD include interaction with cholinergic neurotransmitter system, cholinergic neurotrophic and neu roprotective effect, improvement of learning and memory, improvement of cer ebral blood flow and metabolism, antioxidant and antiinflammatory action, a nd interference with beta-amyloid protein metabolism and toxicity. Estrogen use in postmenopausal women may offer a new approach for improving cogniti ve functions in nondemented and demented women, delaying the onset and prog ression of AD and reducing its occurrence. However, prospective clinical tr ials are required to establish the efficacy of ERT for prevention and treat ment of AD. (C) 1998 Prous Science. All rights reserved.