If you are within five years of menopause, considering starting HRT now. Alternatively, if you are 65 or older, don’t even think about it!
The findings of a large meta-analysis (presented at the 150th Annual Meeting of the American Neurological Association) show that the age at which a woman begins hormone replacement therapy could have a major impact on her chances of developing Alzheimer disease:
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Women who start hormone replacement therapy within five years of menopause lower their risk of developing Alzheimer’s disease by 20%-32%.
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But those who start hormone replacement therapy after age 65 increase their risk of developing the disease by 38%.
The study also included new information regarding how hormone replacement therapy affects brain changes seen on scans or in laboratory tests.
After menopause, natural estrogen levels drop, but HRT sustains the benefits of estrogen, helping brain cells communicate with each other and thereby calming inflammation and protecting against damage that can lead to Alzheimer’s.
However, the theory goes, 10+ years after menopause, the brain may already have early and undetectable signs of Alzheimer’s, such as protein clumps or reduced blood flow, and adding estrogen may stress the brain’s blood vessels.
There are various types of HRT for women, including estrogen alone, estrogen and progestin (a synthetic form of progesterone) together, and estrogen plus a selective estrogen-receptor modulator. The therapy might be in pill or patch form and is often used to treat hot flashes and sleep disturbances and may prevent bone loss and help with heart health. Around 5% of women in the U.S. use HRT, down from nearly 26% in 1999.
The evidence isn’t strong enough to suggest that HRT will prevent Alzheimer’s altogether. But if a woman is planning to start HRT for menopause symptoms, start soon after menopause to maybe get a two-fer.
In addition, women should consider stopping HRT—but please talk to your doctor first!—after a few years to avoid raising the risk of Alzheimer’s.
Source: News Release from the American Neurological Association, September 15, 2025
This content is for informational purposes only and should not be taken as medical advice; always consult a licensed physician before making any medical decisions or changes to your treatment plan.