HRT can help stave off dementia – but only if women take it when they start menopause

A study finds that hormone replacement therapy can reduce the risk of dementia in women with early menopause – but only if they start treatment right away.

Women make up about two-thirds of people with Alzheimer’s disease, and early menopause is associated with an increased risk of developing the disease.

A study now claims that those who are prescribed HRT since the onset of symptoms are not at greater risk.

But women who started the treatment — which helps control symptoms of menopause — several years later had higher levels of two key proteins implicated in dementia, beta-amyloid and tau.

It’s not yet clear how menopause and hormone therapy affects the brain, experts said, and more research is needed.

In the latest study, researchers from Mass Brigham, Boston, US, used brain imaging to study how the presence of two proteins implicated in Alzheimer’s disease relates to age at menopause and use of HRT.

They studied scans of 292 non-cognitively disabled adults to determine levels of amyloid and tau in seven regions of the brain.

They found that women had higher levels of tau than men of the same age, especially in cases where they had a higher level of amyloid beta.

Tau levels were elevated in areas of the brain close to the brain’s memory center and areas known to be involved in the development of Alzheimer’s dementia.

The association between abnormal levels of the proteins was stronger in women who had undergone early menopause, defined as those under the age of 45, than in women in the general population.

Since many women undergoing early menopause often use HRT, the researchers wanted to examine whether its use was related to the two proteins.

Starting treatment late — five or more years after the onset of menopause — was associated with higher levels of beta-amyloid and tau, according to the JAMA Neurology findings.

“We found that the highest levels of tau, a protein implicated in Alzheimer’s disease, were only observed in female hormone therapy users who reported a prolonged delay between the age at onset of menopause and the start of hormone therapy,” said Rachel Buckley, of Massachusetts General Hospital. .

“The idea that tau deposition might underlie the association between delayed hormone therapy intervention and Alzheimer’s dementia was a huge discovery, something that hadn’t been seen before.”

Evidence for a role for HRT in dementia has so far been inconclusive, with research suggesting it can have protective and potentially harmful effects.

In January, a study by University of East Anglia researchers suggested that HRT may help prevent Alzheimer’s disease in women who carry the APOE4 gene, which puts them at increased risk.

This suggests that HRT was most effective when given during the perimenopausal period, when symptoms build up months or years before menstruation actually stops.

Alzheimer’s Research UK said larger studies are needed to help understand the relationship between HRT and changes in the brain.

The charity cited conflicting past research, with some highlighting the potential cognitive benefits of HRT while other studies pointing to an increased risk of memory and thinking problems.

“While this study contributes valuable new data to this topic, we are still unable to indicate a definitive association between hormone therapy and Alzheimer’s disease or dementia,” said lead researcher Dr Sarah Imaricio.

It is important that people are empowered with evidence-based advice that allows them to make informed decisions about their health. But there’s a lot to understand about how menopause and HRT affect dementia risk.

We need to see larger studies and controlled clinical trials to better understand this complex area of ​​research and the conflicting results that have emerged in recent years.