Nikhil Prasad Fact checked by:Thailand Medical News Team Mar 22, 2026 1 hour, 37 minutes ago
Medical News: Hormone therapy has long been used to ease menopause symptoms such as hot flashes, sleep disturbances, and mood swings. However, concerns about its possible link to dementia have persisted for years. A new long-term study now sheds fresh light on this issue, suggesting that a specific Alzheimer’s-related blood marker may help identify which women are more vulnerable to cognitive decline when using certain types of hormone therapy.
Blood biomarker may reveal which women face higher dementia risk with hormone therapy
A Blood Marker That Predicts Future Risk
Researchers analyzed data from 2,766 women who participated in the Women’s Health Initiative Memory Study, conducted across 39 clinical sites in the United States. The women, aged 65 to 79 at the start, were followed for up to 25 years, until 2021. Scientists later measured levels of a protein called plasma phosphorylated tau 217 (p-tau217) in stored blood samples.
This protein is considered a key biomarker for Alzheimer’s disease. Higher levels are linked to harmful changes in the brain, particularly involving tau proteins that disrupt normal nerve function. The findings showed that women with higher p-tau217 levels had about three times the risk of developing dementia compared to those with lower levels.
Hormone Therapy Makes a Difference
Interestingly, the type of hormone therapy used appeared to significantly influence this risk. Women who received combined hormone therapy—containing both estrogen and progesterone—had an even greater increase in dementia risk if their p-tau217 levels were high. In this group, the risk rose to more than four times higher.
In contrast, women who used estrogen-only therapy did not show the same increased risk, even if their biomarker levels were elevated. This suggests that progesterone may play a role in modifying how estrogen affects brain health, although the exact mechanisms are still unclear.
Who Is Most at Risk?
The study also found that certain groups were more vulnerable. Women over the age of 70, those carrying the APOE ε4 gene (a known genetic risk factor for Alzheimer’s), and White women showed stronger associations between high p-tau217 levels and dementia risk.
Researchers noted that while both Black and White women showed increased dementia risk with higher biomarker levels, the association was stronger in White women. However, when age and biomarker levels were combined, prediction accuracy was similar across both groups.
Revisiting Earlier Findings
This
Medical News report highlights how these findings align with earlier research. Past studies from the same program had already shown that combined hormone therapy could double dementia risk in women over 65. Those trials were stopped early due to increased risks of breast cancer, stroke, and blood clots.
More recent research has suggested that timing
is critical. Women who begin hormone therapy around menopause, typically in their early 50s, generally do not face the same cognitive risks, especially when treatment is limited to a few years.
What This Means for Women
Importantly, the study does not prove that hormone therapy directly causes dementia. Instead, it suggests that underlying biological risk—measured through markers like p-tau217—plays a crucial role. Hormone therapy may amplify existing vulnerabilities rather than create new ones.
Conclusion
The findings provide a more personalized understanding of dementia risk in women considering hormone therapy. Rather than applying a one-size-fits-all approach, doctors may eventually use biomarkers like p-tau217 to identify individuals who could safely benefit from treatment and those who may face higher risks. The results also emphasize that age, genetics, and timing of therapy are critical factors that must be carefully considered. While hormone therapy remains an effective option for managing menopausal symptoms, its long-term impact on brain health appears to depend on a complex interplay of biological and treatment-related factors that require further investigation.
The study findings were published in the peer reviewed journal: JAMA Network Open.
https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2846152
For the latest on menopause issues, keep on logging to Thailand
Medical News.
Read Also:
https://www.thailandmedical.news/articles/menopause
Share
Tweet
Share
