Could Menopause Hormone Therapy Help Protect Memory?

Spoiler Alert: Maybe. But It’s Too Soon to Know

Could a treatment for hot flashes also help protect against Alzheimer’s disease?

A new study raises that possibility. But the potential benefit remains unconfirmed: Researchers have not proved that estrogen prevents Alzheimer’s, and women should not start or change hormone therapy for that purpose based on these findings.

The Stanford-led researchers found that women who reported taking estrogen-only menopause hormone therapy had fewer signs of Alzheimer’s in their brains after death. They were also less likely to have been diagnosed with dementia while alive. The study appeared online Aug. 12 in the journal Neurology.

While this is an encouraging finding, especially for women concerned about memory loss as they age, much more testing must be done to determine if estrogen accounts for the difference in these results.

What the study found

Researchers examined records from two large research databases for 21,462 women. A smaller group—2,959 women—had their brains examined after death. Of those women, 258 had reported using estrogen-only hormone therapy, while 2,701 had reported no menopause hormone therapy use.

The brain examinations looked for the protein buildups associated with Alzheimer’s disease: amyloid plaques and tau tangles. Studying brain tissue let researchers see disease-related changes directly, rather than relying only on memory tests or medical diagnoses.

After accounting for differences between the women, including age, education, genetics and high blood pressure, researchers found that estrogen users had 35% lower odds of Alzheimer’s-related brain changes. Hormone use was also associated with 39% lower odds of a dementia diagnosis. Some blood and spinal-fluid tests supported the findings.

Those percentages need careful interpretation. They describe statistical differences between groups. They do not mean that estrogen prevented dementia in 39 out of every 100 women, or that taking it would reduce an individual woman’s lifetime risk by 39%.

Why the answer is still uncertain

This was an observational study: Researchers looked back at existing information about women who used different treatment approaches. They did not randomly assign women to receive estrogen or a placebo—a pill without the active medication—and then compare what happened.

That matters because women who take hormone therapy may differ from women who do not. They might have better access to medical care, different health histories or other advantages that help explain their outcomes.

Researchers can adjust their calculations for known differences. They cannot account for everything.

The women were also generally older, and their treatment histories reflected medical practices that differed from those commonly used today.

“The results are informative, but they may not apply to today’s standards,” study author Jennifer Bruno, a Stanford researcher, said in the American Academy of Neurology’s announcement. www.aan.com

The type of hormone treatment matters

The study focused on estrogen-only therapy. Its findings do not apply to every menopause treatment. Women who have had a hysterectomy—surgery to remove the uterus—can generally take estrogen alone. Women who still have a uterus usually need another hormone, a progestogen, alongside estrogen to protect against cancer of the uterine lining. Progesterone is one type of progestogen.

The researchers did not have enough brain-autopsy information to draw firm conclusions about treatment combining estrogen and a progestin. A woman taking combined treatment should therefore not interpret this study as a reason to stop its progesterone or progestin component.

The findings also do not establish that low-dose vaginal estrogen prevents dementia. That treatment is used for symptoms such as vaginal dryness and delivers very little estrogen into the bloodstream. It differs from hormone treatment that circulates throughout the body.

Haven’t earlier studies suggested hormone therapy could harm memory?

Yes. That is one reason researchers are treating the new findings cautiously.

The Women’s Health Initiative Memory Study tested particular hormone pills in women ages 65 and older. Women assigned to take estrogen combined with the progestin medroxyprogesterone acetate developed probable dementia at about twice the rate of women taking a placebo.

A separate estrogen-only trial also recorded more dementia diagnoses among women taking the hormone. However, the difference was small enough that researchers could not rule out chance. That trial did not show that estrogen prevented dementia. The studies used different treatments, circumstances and research methods. The newer results do not erase the earlier findings or settle the question.

Age and timing also affect hormone therapy’s overall benefits and risks. The Menopause Society says risks are generally lower for healthy women starting treatment near menopause and greater for women beginning at older ages or many years afterward. That does not prove that starting early prevents Alzheimer’s.

What does this mean for your treatment?

Hormone therapy has established benefits. It can ease hot flashes, night sweats and other menopause symptoms, and help prevent bone loss. Federal guidance says benefits are more likely to outweigh risks for women who begin treatment before age 60 or within 10 years of menopause. The decision still depends on a woman’s health history and the treatment being considered.

The same guidance says experts do not yet know whether hormone therapy prevents dementia.

For women already using hormone therapy, or wondering whether to try it, the study can be part of a medical conversation. It should not determine the decision.

Useful questions to ask your doctor include:

• Which of my symptoms could hormone therapy help?

• How do my age and health history affect its benefits and risks?

• Which treatment is appropriate for me?

• If I am already taking hormones, is there a reason to change anything?

  
  

And what about menopause “brain fog”?

Trouble concentrating or remembering things can occur around menopause. Poor sleep and mood changes can also affect how clearly you think. These experiences do not automatically mean Alzheimer’s disease is developing.

Still, noticeable changes deserve a discussion with a healthcare professional. The Menopause Society does not recommend hormone therapy specifically to improve thinking or memory in women going through natural menopause. It identifies exercise, mental activity, social connections, not smoking, and managing conditions such as high blood pressure and diabetes as ways to support brain health.