Hormone Therapy Linked to Lower Dementia Risk in Post-menopausal Women

A large U.K. cohort study of more than 180,000 post-menopausal women reported that hormone replacement therapy lowered the chance of any dementia by 10% and Alzheimer’s disease by 16%, even after adjusting for ethnicity, smoking, education and other factors. Women who experienced surgical menopause saw an even larger benefit, with a 26% risk reduction, and those who started therapy between ages 46 and 56 fared better than later starters.

A companion study published in JAMA Network Open linked earlier onset of menopause to greater cognitive decline and earlier Alzheimer’s diagnosis, with the effect most pronounced in surgical-menopause cases and associated with increased white-matter hyperintensity volume. Experts note that these findings suggest menopause timing and hormone treatment could be critical in brain health, but they caution that observational data cannot confirm that hormone therapy prevents dementia. Ongoing research aims to clarify mechanisms, test clinical interventions, and explore whether dietary phytoestrogens might also support cognition.