A landmark international review has concluded that taking hormone replacement therapy (HRT) has no significant effect on a woman's likelihood of developing dementia. The analysis, which examined over one million women, found 'no evidence' that the treatment either increases or decreases the risk of the disease.
Cutting Through the Noise on HRT and Brain Health
The research team, comprising scientists from the UK, Ireland, Switzerland, Australia, and China, analysed data from 10 separate studies. Their goal was to settle the long-standing and often conflicting debate about whether HRT influences cognitive decline. The review specifically looked at the risk of both mild cognitive impairment (MCI) and dementia in women before and after the menopause.
The findings, published in The Lancet Healthy Longevity, revealed 'no significant association' between the use of HRT and the risk of either MCI or dementia. This conclusion held true regardless of when the therapy was started, how long it was taken for, or the type of hormones used, such as oestrogen, progesterone, or testosterone.
Informing Global Health Policy
Experts involved in the study stated that HRT should be prescribed based on its well-established benefits for managing menopausal symptoms—like hot flushes, night sweats, and mood swings—and not for dementia prevention. The team hopes their work will directly inform crucial upcoming guidelines from the World Health Organisation (WHO) on reducing cognitive decline, expected in 2026.
Professor Aimee Spector from UCL's psychology and language sciences department explained the importance of the review. 'To cut through the noise, we reviewed the most rigorous research there is on the subject,' she said. The current lack of WHO guidance on menopause hormone therapy and cognitive outcomes leaves a critical gap for clinicians and policymakers worldwide.
Expert Reaction and the Call for Further Research
While the review provides clarity, it also highlights areas needing more investigation. The researchers called for further high-quality studies to clarify the role of hormone therapy, particularly for women who experience early menopause or already have mild cognitive impairment.
Menopause specialist Dr Louise Newson offered a nuanced perspective, noting that the hormones in modern body-identical HRT play vital roles in brain health. 'Women who are prescribed HRT... have more benefits than risks and... improve their symptoms - including memory problems,' she stated, emphasising the therapy's proven benefits for bone and heart health.
With an estimated 982,000 people living with dementia in the UK, around two-thirds of whom are women, this research provides much-needed evidence for millions making decisions about menopause management.
