A comprehensive review led by University College London researchers has found no evidence that menopause hormone therapy affects the risk of dementia in post-menopausal women. The study, supported by the University of Exeter and commissioned by the World Health Organisation (WHO), was published in The Lancet Healthy Longevity. It provides clarity on a contentious issue, reinforcing guidelines that hormone therapy should be based on individual benefits and risks rather than dementia prevention.
The findings come amid ongoing debates about the safety and efficacy of menopause hormone therapy, also known as hormone replacement therapy (HRT). Professor Chris Fox from the University of Exeter Medical School stated, “The role of menopause hormone treatment and its relationship to dementia is a worry for many women. But our state-of-the-art review indicates there is no evidence that menopause hormone treatment reduces or increases the risk of dementia.”
Key Insights from the Study
The systematic review and meta-analysis represent the most comprehensive synthesis of evidence on menopause hormone therapy and dementia risk to date, involving data from over one million participants. This extensive research effort included one randomized controlled trial and nine observational studies, covering a total of 1,016,055 participants.
The study’s publication follows a significant decision by the U.S. Food and Drug Administration (FDA) in November to remove ‘black box’ warnings from menopause hormone therapy products. These warnings had previously suggested potential long-term health risks, including increased dementia risk, which have now been disproven.
“Menopause hormone therapy is widely used to manage menopausal symptoms, yet its impact on memory, cognition, and dementia risk remains one of the most debated issues in women’s health,” said Melissa Melville, lead author and PhD student at UCL Psychology & Language Sciences.
Global Implications and Future Research
The international research team, with members from the UK, Ireland, Switzerland, Australia, and China, found no significant association between menopause hormone therapy and the risk of dementia or mild cognitive impairment. Even when analyzing subgroups based on timing, duration, and type of therapy, no significant effects were observed.
However, the researchers caution that the findings are limited by the scarcity of relevant randomized controlled trials, and much of the evidence is of relatively low certainty. They emphasize the need for high-quality, long-term research, especially among women from ethnic minority backgrounds or those experiencing early menopause, premature ovarian insufficiency, or mild cognitive impairment.
Senior author Professor Aimee Spector from UCL noted, “Currently, the World Health Organisation provides no guidance on menopause hormone therapy and cognitive outcomes, leaving a critical gap for clinicians and policymakers.”
Looking Ahead: WHO Guidelines and Ongoing Debates
This review is expected to inform upcoming WHO guidelines on reducing the risk of cognitive decline and dementia, anticipated in 2026. The findings underscore the importance of continued research to fully understand the long-term impacts of menopausal hormone therapy.
Despite the study’s findings, the debate over hormone therapy’s role in women’s health is likely to continue. As researchers call for more robust studies, the medical community and patients alike await clearer guidance on navigating the complex landscape of menopause treatment options.
As the scientific community advances in understanding the nuances of hormone therapy, women and healthcare providers must weigh the benefits and risks carefully, ensuring decisions are informed by the latest evidence.
