A study conducted by researchers at Stanford University, published on August 12 in the journal Neurology, indicates that women who used estrogen-only menopausal hormone therapy (MHT) may have a reduced risk of developing Alzheimer's-related brain changes and dementia. The study analyzed post-mortem data from 21,462 participants, comparing 258 women who reported using estrogen-only MHT with approximately 2,701 women who did not use MHT.
The findings suggest that women who took estrogen-only therapy had a 35% lower chance of Alzheimer’s pathology and a 39% lower likelihood of developing dementia over their lifetime. Additionally, some living participants who used estrogen-only therapy performed better on memory tests and demonstrated greater independence. The average age of participants was 70 years.
The researchers noted that starting menopausal hormone therapy during or shortly after menopause may yield greater benefits, and the results could understate the potential advantages of earlier therapy. These findings contrast with previous studies that associated menopausal hormone therapy with an increased risk of dementia.
Co-author Jennifer Bruno, PhD, stated that estrogen has neuroprotective effects in animal models and plays a role in reducing amyloid and tau, which are associated with Alzheimer’s disease. However, the study's observational nature means it can only show an association and not causation. Senior author Hadi Hosseini, PhD, emphasized the importance of conducting well-designed clinical trials to further investigate the effects of MHT on brain health. The study was funded by the National Institutes of Health.