Studies are underway internationally to answer the question.
Because some women are concerned about potential cancer risks with taking estrogen, researchers have also asked whether estrogen alternatives, such as selective estrogen-receptor modulators, might also prevent cognitive decline. A team of researchers led by Dr. Kristine Yaffe of the Department of Psychiatry at the University of California at San Francisco studied 7,478 postmenopausal women with osteoporosis in 25 countries. The women were given six different tests of cognitive function, first when they entered the study and then at six months and one, two and three years. There were no significant differences in overall cognitive scores between the three groups after three years. Studies will continue to explore the potential value of estrogen and estrogen substitutes in improving cognition and perhaps preventing Alzheimer's.