Approved Research

Sex and sexual orientation differences in biological aging

Lay summary

Women are less likely to die from virtually every common cause of death. The notable exception to this rule is dementia, which affects women more frequently than men. Indeed, medicines that aim to prevent dementia works less effectively for women. It is possible that women have unique patterns of neurodegeneration that predispose them to dementia. In this project, we will first describe any sex differences in brain aging that might help explain the increased prevalence of dementia among women. We will do this using magnetic resonance imaging (MRI) scans of the brain. In addition, we will test for sex differences in aging-related biomarkers of several other organ systems. This will allow us to compare sex differences in 'whole-body' aging to sex differences in 'brain aging.' We may learn that certain sex differences in aging are unique to the brain, or that the same pattern of sex difference occurs across the entire body. This could one day help to develop drugs or therapies that could protect women from developing dementia, given their increased risk for the disease.

We also will test whether social discrimination against homosexual, bisexual, and lesbian people (henceforth: sexual minorities) leads to accelerated aging across the entire body. Social discrimination against racial minorities is known to contribute to health disparities during old age. In other words, racial minorities experience aging-related illness more frequently because they face the lifelong stress of social discrimination. Sexual minorities also face social discrimination, but it is not clear whether these people also face health disparities during old age. We will use many different biomarkers to test whether sexual minorities show accelerated aging across different organ systems. We may learn that sexual minorities have faster aging, suggesting this group is at greater risk for aging-related diseases. Alternatively, we could learn that these groups do not show accelerated aging, suggesting that they might not be at increased risk for disease during old age. Understanding who is most at risk for disease will help us target treatments to people who need them most.

This project will last 36 months. We anticipate that it will take two years to check the quality of the data, analyze the data, and understand the results. We then predict that it will take one year to write a manuscript, peer-review it, and publish our findings in a medical journal.