How Menopause Impacts Alzheimer's Risk & How To Keep Your Brain Healthy

Women are twice as likely as men to develop Alzheimer's, which has long been attributed to the fact that women live longer than men and the risk of Alzheimer's increases as we age. But emerging research has found another contributing factor: the dramatic hormone changes we experience during the menopausal transition.

These changes, especially the loss of estrogen, can increase neuroinflammation and, according to neuroscientist Lisa Mosconi—director of the Women's Brain Initiative and of the Alzheimer's Prevention Program at Weill Cornell Medicine/New York-Presbyterian Hospital—accelerate the chronological aging in the female brain. It's this aging that can equal increased risk of Alzheimer's disease as women undergo menopause.

You are at increased risk of neuroinflammation if you have high blood pressure, high cholesterol, heart disease, and/or Type 2 diabetes. These conditions are pro-inflammatory and can directly compromise the health of your heart and blood vessels, which are responsible for transporting essential oxygen to your brain.

Nearly everyone who goes through the menopausal transition will experience an uptick in inflammation, including in the area of the brain. This is an inevitable consequence of the decline of estrogen, which I've already pointed out plays a crucial role in regulating inflammation. Estrogen is also essential to managing certain neurological functions. It's no wonder then that menopause can affect clarity of thought, concentration, calmness, and other brain-related abilities and behaviors.

Unfortunately, there aren't any approved or effective tests to check for neuroinflammation. But we can sort of nonscientifically measure our cognitive response to diminishing levels of estrogen by paying attention to the severity of brain-related symptoms of menopause. This can include symptoms like brain fog and forgetfulness and anxiety and depression.

Most women will experience some of these symptoms, to varying degrees. "This isn't surprising when you think about how many menopausal symptoms—including hot flashes, depression, anxiety, sleep disturbances, and even brain fog—actually stem from the brain rather than the ovaries," says Mosconi.

Generally, the symptoms will get better as estrogen stabilizes, and you'll establish a kind of postmenopausal norm (it's unlikely you will ever return to a premenopausal status quo). However, for some women, there will be a progression in the area of cognitive decline that may eventually lead to the diagnosis of dementia.

There has yet to be a sweeping study saying that MHT is brain-protective for all women who are in or approaching menopause. But some research shows that it is effective for specific groups and not recommended for others.

As I mentioned in Chapter 4, research published in 2023 found that carriers of the APOE4 gene, which is associated with a higher risk of developing Alzheimer's disease, experienced improved memory recall speed and larger volumes in brain areas when taking hormone replacement therapy (when compared to nonusers).

Hormone therapy has also been shown to be significantly neuroprotective when used by women who had a bilateral oophorectomy (removal of both ovaries) prior to the age of 50 and somewhat protective in those who used MHT in the early menopausal stage, which is generally between the ages of 50 and 60.