Women are carrying a heavier load when it comes to dementia risk, and it is showing up in their brain health sooner than many might think, according to new UC San Diego research that zeroes in on midlife and early older age. The findings give local clinicians and public health planners fresh reasons to consider sex-specific strategies for preventing cognitive decline.
The peer-reviewed study, led by UC San Diego neuroscientists Megan Fitzhugh and Judy Pa, was published May 20 in Biology of Sex Differences. Using data from the long-running Health and Retirement Study, the team analyzed 17,182 participants aged 40 and older and tracked 13 modifiable dementia risk factors, including hearing loss, hypertension, sleep quality and alcohol use.
Sex-specific risk gaps
In this national sample, women were more likely than men to report depression (17% vs. 9%), physical inactivity (48% vs. 42%) and sleep problems (45% vs. 40%). Men, on the other hand, reported higher rates of hearing loss (64% vs. 50%), diabetes (24% vs. 21%) and heavy alcohol use (22% vs. 12%). Hypertension affected roughly six in 10 participants in both groups, and the average BMI landed in the overweight-to-obese range regardless of sex. These prevalence patterns were laid out in a campus release that noted that UC San Diego researchers were flagging how everyday health issues differ for women and men, according to UC San Diego.
Beyond who had which risk factors, the team also showed that some of those risks had a bigger cognitive impact on women. Hearing loss, diabetes and high blood pressure were all tied to larger drops in the study’s cognitive score for women than for men.
“Looking beyond which risk factors are most common, we found that some have a disproportionately larger impact on women’s cognition,” Fitzhugh said in the university release. Pa added that sex differences are profoundly overlooked among many leading causes of death like Alzheimer’s, heart disease and cancer, per UC San Diego.
What this means for prevention
The authors argue that the pattern they observed - women often facing higher exposure to certain risks plus stronger cognitive effects from some of those same risks - may help explain why nearly two-thirds of Americans living with Alzheimer’s are women and why it matters to build sex-aware prevention efforts. The paper notes that the Lancet Commission has estimated that tackling modifiable risks could trim dementia cases by about 45%, and it points to growing evidence that prevention in midlife should be tailored with both women and men in mind. Biology of Sex Differences
Locally, the work drew attention from The San Diego Union-Tribune, which highlighted the team’s recommendation that clinicians keep a closer eye on midlife conditions such as hypertension, depression and sleep disorders. The coverage also served as a reminder that campus research can nudge public conversations about prevention across the region.
UC San Diego scientists are already pursuing related projects, including the Women: Inflammation and Tau Study, which is examining how sleep and inflammation interact with sex to shape Alzheimer’s risk. Researchers say practical takeaways could eventually include better screening for hearing loss, more aggressive blood-pressure control during midlife and more deliberate attention to mood and sleep health. For now, their latest paper lands on a blunt takeaway: any risk-reduction strategy that ignores sex differences is likely missing a crucial part of the dementia puzzle.
