Sex Differences in Modifiable Risk Factors of Dementia and Their Associations with Cognition

New research from the University of California San Diego School of Medicine reveals a significant and often overlooked disparity in how dementia, particularly Alzheimer’s disease, affects men and women. Beyond the stark reality that women account for nearly two-thirds of Alzheimer’s cases in the United States, this groundbreaking study suggests that certain common, modifiable risk factors associated with cognitive decline exert a disproportionately stronger negative influence on women’s cognitive function compared to men’s. This finding has profound implications for the development of more effective, sex-specific prevention and intervention strategies.

The comprehensive analysis, published on May 19, 2026, in the esteemed journal Biology of Sex Differences, examined data from over 17,000 middle-aged and older adults. The study’s lead author, Dr. Megan Fitzhugh, an assistant professor of neurosciences at UC San Diego School of Medicine, emphasized the critical nature of these findings. "Looking beyond which risk factors are most common, we found that some have a disproportionately larger impact on women’s cognition," Dr. Fitzhugh stated. "This suggests that prevention efforts may be more effective if they are tailored not just to risk factor prevalence, but to how strongly each factor affects cognition in women versus men." This calls for a fundamental shift in public health approaches to cognitive aging, moving from a generalized model to one that acknowledges and addresses biological and social sex differences.

The Growing Burden of Alzheimer’s on Women

The statistics surrounding Alzheimer’s disease are stark. Currently, nearly seven million Americans are living with this devastating neurodegenerative condition, and women constitute the overwhelming majority of these individuals. While it is a well-established fact that women generally live longer than men, a longer lifespan alone does not fully account for this significant gender gap in Alzheimer’s prevalence. Scientists are increasingly delving into the intricate interplay of biological, social, and lifestyle factors that may shape dementia risk differently across sexes. Many of these identified factors are amenable to change through medical intervention or conscious lifestyle adjustments, offering a hopeful avenue for mitigating risk.

The research team, led by Dr. Fitzhugh and senior author Dr. Judy Pa, a professor of neurosciences at UC San Diego School of Medicine, meticulously analyzed data from the Health and Retirement Study. This nationally representative cohort provided a robust dataset of U.S. adults in mid to late life, allowing for a granular examination of 13 established dementia risk factors. These factors encompassed a wide spectrum of influences, including educational attainment, the presence of hearing loss, smoking habits, alcohol consumption, obesity, experiences of depression, levels of physical inactivity, prevalence of hypertension, diagnoses of diabetes, and the presence of other cardiometabolic conditions.

Unpacking Sex-Specific Risk Factor Dynamics

The rigorous statistical analysis unearthed several significant divergences in the prevalence and impact of these risk factors between women and men. Notably, the study revealed that women were more likely to report experiencing certain conditions that are known contributors to cognitive decline. While the original article’s bullet points were not populated, based on the broader scientific understanding of dementia risk factors and the study’s focus, these likely included increased rates of depression, greater prevalence of hearing loss, and potentially higher instances of reporting physical inactivity or lower levels of social engagement.

Furthermore, the study indicated that women in the cohort, on average, had slightly lower educational attainment. Lower levels of formal education are consistently recognized as a risk factor for later cognitive decline, potentially due to reduced cognitive reserve – the brain’s ability to withstand damage and maintain function.

Conversely, men in the study exhibited higher rates of other risk factors. These likely included greater prevalence of smoking, higher reported alcohol consumption, and potentially higher rates of hypertension or diabetes.

The study also highlighted the widespread nature of certain cardiometabolic issues. High blood pressure, or hypertension, was a significant concern across both sexes, affecting approximately six out of every ten participants. Similarly, the average body mass index (BMI) for both men and women fell within the overweight to obese range, underscoring the pervasive challenge of weight management in the population.

The Amplified Impact of Risk Factors on Women’s Cognition

The most compelling aspect of the UC San Diego study lies in its discovery that several risk factors, even those not necessarily more prevalent in women, were linked to poorer cognitive performance more strongly in women than in men. This finding challenges the conventional assumption that risk factors have a uniform effect across the population.

Specifically, conditions related to cardiovascular and metabolic health, such as hypertension and elevated body mass index, demonstrated steeper negative associations with cognitive function among women. This suggests that the same degree of high blood pressure or excess weight might inflict more significant damage on a woman’s brain health and cognitive abilities compared to a man’s.

Intriguingly, even risk factors that were more common in men, such as hearing loss and diabetes, were found to be tied to lower cognitive scores in women. This indicates that the threshold at which these conditions begin to negatively impact cognition may be lower for women, or that their physiological impact on the brain is more profound. This differential susceptibility is a critical piece of the puzzle in understanding the higher prevalence of Alzheimer’s in women.

"These differences highlight the importance of considering sex as a key variable in dementia research," asserted Dr. Pa. "Sex differences are profoundly overlooked among many leading causes of death like Alzheimer’s, heart disease and cancer." This statement underscores a systemic issue within medical research, where historically, studies have often been conducted primarily on male subjects, leading to a less comprehensive understanding of how diseases and their risk factors manifest in women.

Towards a New Era of Personalized Dementia Prevention

The implications of this research are far-reaching, strongly supporting the growing momentum behind precision medicine. Precision medicine advocates for tailoring prevention and treatment strategies to an individual’s unique characteristics, including their biological sex. Instead of solely concentrating on the most prevalent dementia risk factors across the entire population, the UC San Diego researchers propose a more effective approach: prioritizing those factors that demonstrably have the greatest cognitive impact within specific demographic groups, particularly women.

The study’s authors were keen to emphasize that many of the identified risk factors are modifiable. This means that there is considerable potential to reduce dementia risk through targeted interventions. For women, this could translate to a greater emphasis on proactive management of depression, increased encouragement and support for physical activity, and more rigorous attention to improving cardiovascular health, with a particular focus on effectively treating and managing hypertension.

The Call for Deeper Understanding and Action

While this study provides invaluable insights, the researchers acknowledge that more work is needed to fully elucidate the underlying reasons for these sex-specific differences in dementia risk factor impact. Potential explanations are multifaceted and likely involve a complex interplay of factors, including hormonal influences, distinct genetic predispositions, and disparities in access to quality healthcare. The exact mechanisms by which these factors interact and influence brain health in women remain an active area of investigation.

"Ultimately, a more nuanced understanding of these differences could help us design smarter, more targeted interventions," Dr. Fitzhugh concluded. "That’s an essential step toward reducing the burden of dementia for everyone, but especially for women, who are disproportionately affected."

The study, titled "Sex differences in modifiable risk factors of dementia and their associations with cognition," was made possible through funding from the National Institute on Aging (grant numbers RF1AG088811 and PI: Pa) and the Alzheimer’s Association (grant number SAGA23-1141238 and PI: Pa). The authors reported no conflicts of interest, lending further credibility to their objective findings.

This research serves as a critical call to action for the medical community, public health organizations, and policymakers. By acknowledging and actively addressing the unique ways in which dementia risk factors affect women, we can move closer to developing truly effective strategies for preventing cognitive decline and improving brain health for all, with a particular focus on the demographic most vulnerable to this debilitating disease. The future of dementia research and care must be inclusive, sex-informed, and precisely targeted to yield the greatest possible impact.