Two-thirds of individuals suffering from Alzheimer’s disease are women. The reason for women’s increased risk of Alzheimer’s disease is unknown. Menopause occurs when a decline in a hormone called estrogen causes middle-aged women to stop having menstrual periods. Early menopause can increase the risk of Alzheimer’s disease. Vascular conditions, such as high blood pressure, high cholesterol, and diabetes, also increase the risk of Alzheimer’s disease and brain changes in both sexes, but more so in women. In the proposed study, we test whether earlier age at menopause and vascular conditions together lead to worse cognition (thinking and memory abilities) and Alzheimer’s brain changes in postmenopausal women. We also investigate whether taking hormone therapy to replace lost estrogen can protect against the memory and brain changes caused by Alzheimer’s disease. We will study women aged 55-85 who self-identify as East Asian or South Asian ancestry. We are studying these ethnic groups because they are at increased risk of vascular conditions and remain understudied in dementia research. This will be one of the first studies to investigate women’s increased risk for Alzheimer’s disease in a multi-ethnic group. Understanding why women are more vulnerable to Alzheimer’s disease is important for developing ways to prevent and treat dementia in both men and women. Increasing diversity of research participants will ensure that the development of dementia prevention and treatment strategies are effective for all individuals.