Women make up a significant majority of those living with dementia today. In the U.S., for example, roughly two-thirds of the 6 million-plus people diagnosed with Alzheimer’s dementia are women.

While the whys behind this sex-based trend remain uncertain, research is underway to test many potential factors and contributors.

Until we know more, the signs and symptoms of dementia in women remain the same as those exhibited in anyone else, according to the Alzheimer’s Association.

Greater Burden of Dementia for Women

Beyond the actual individual diagnosed, research also shows that women account for roughly 60 percent of the 11 million individuals providing care for those with Alzheimer’s today. This compounds the ways that dementia disproportionally impacts the lives of females. 

“We know there is more of a burden with this disease on women,” says Heather Snyder, molecular biologist and vice president of medical and scientific relations at the Alzheimer’s Association. “[But] we can’t necessarily say women are at greater risk for Alzheimer’s.”

For now, potential sex-based contributors of dementia may include total years of reproductive health, age of menstruation, age of menopause and total number of months spent pregnant for any individual.

“All of those may contribute or have been associated with greater life risk of dementia,” Snyder says.

But more studies and trials are needed to hone in on how things like estrogen levels, or the X chromosome itself might intersect with Alzheimer’s and other neurodegenerative diseases that cause dementia.

Read More: Alzheimer’s Disease Isn’t the Only Cause of Dementia

Women Live Longer

Part of the skewed numbers toward women might be attributed to the simple fact that women on average live longer than men. And risk of dementia increases with age.

Specifically, some studies indicate that the human lifespan is on average 8 percent longer for women compared to men. In the U.S., male life expectancy is 73.5 years old, compared to 79.3 for females, a difference of roughly six years, according to 2021 CDC statistics.

Still, numerous studies have demonstrated that this age differential isn’t the only factor attributing to trends and symptoms of dementia in women.

“It is certainly part of the puzzle, but it is not the whole story,” Snyder says of lifespan.

Read More: A Second X Chromosome Could Explain Why Women Live Longer Than Men

Top Signs of Dementia

The Alzheimer’s Association has compiled a research-based list of the top 10 early signs of Alzheimer’s. This applies to early signs of dementia in women and anyone with concerns about the disease.

Here are the warning signs to watch out for from the Alzheimer’s Association:

• Memory lost disrupting daily life

• Challenges in planning or solving problems

• Difficultly completing familiar tasks

• Confusion with time or place

• Trouble understanding visual images

• New problems with words (speaking or writing)

• Misplacing things

• Decreased judgement or poor decision making

• Withdrawal from work or social activities

• Changes in mood or personality

Snyder adds that these symptoms may manifest differently from person to person. So it’s important to watch for changes compared to younger years and abilities in a given individual. 

“It’s the idea of being aware of your brain, and your brain health,” Snyder says.

As one company executive put it, early signs in them appeared when they were unable to identify specific words they routinely used in memos. Snyder says they called their spouse to help recall words they were describing: “For them, that was an indicator that something was wrong.”

Sex and Gender Contributors in Dementia

Plenty of researchers have identified a lack of studies probing the sex- and gender-based  differences in Alzheimer’s dementia and how it progresses.

The potential sex-based contributing variables, according to one 2018 study published in Alzheimer’s & Dementia, include biological or hormonal patterns as well as systemic and sociocultural factors — such as access to education and economic stability.

As an example, observational data in multiple studies have shown that women who pursue hormone therapy early in menopause, or prior to it, have a lower risk of Alzheimer’s dementia than women who initiate hormone therapy later.

Snyder also says that various studies continue to probe whether sex and gender bias have informed some of the medical testing currently in place to detect early dementia.

The Rising Cost of Dementia 

One thing that is clear: solutions and improvements on the medical side are needed to help offset the growing cost of dementia in the aging population.

Just this month, the Alzheimer’s Association released new data about the cost of caring for individuals living with dementia.

That report shows the national cost is projected to reach $345 billion — which is a $24 billion increase compared to just one year prior.

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