Gender, sexual identity may be associated with brain health outcomes

Key takeaways:

• LGBTQ+ participants were 15% more likely to experience an adverse brain health outcome compared with straight cisgender people, researchers found.
• Only transgender women had increased risk for stroke.

LGBTQ+ people may be more likely to experience adverse brain health outcomes, including late-life depression and dementia, compared with cisgender straight people, according to study results published in Neurology.

The findings do not show that a person’s sexual orientation or gender identity causes neurological diseases; rather, they reveal an association between the two, according to a press release related to the study.

“In a world that increasingly recognizes the crucial role of equitable health care, it remains concerning how little is known about the health disparities faced by LGBTQ+ people,” Shufan Huo, MD, PhD, postdoctoral fellow in the department of neurology and Yale Center for Brain and Mind Health at Yale University, and colleagues wrote.

Specifically, the intersection of brain health with the health care disparities experienced by LGBTQ+ people is not well understood, they wrote.

This lack of knowledge inspired the researchers to perform a cross-sectional study using 2017 to 2022 data from 393,041 adults (mean age, 51 years; standard deviation [SD], 17 years) in the population-based All of Us Research Program to evaluate if LGBTQ+ people are at higher risk for adverse brain outcomes compared with cisgender straight people.

The researchers used baseline questionnaires to identify LGBTQ+ participants (nonstraight and noncisgender), who were divided into further categorizations within sexual orientation (lesbian, gay, bisexual and diverse) and gender identity (gender diverse and transgender).

The researchers evaluated the primary outcome of brain health — which was a composite of stroke, dementia and late-life depression — using self-report and electronic health record data.

The analysis included three sequential models of adjustment: model 1 adjusted for age, sex assigned at birth and race/ethnicity; model 2 adjusted for cardiovascular comorbidities less prevalent in the LGBTQ+ community and the neighborhood deprivation index; and model 3, which adjusted for the prior covariates as well as comorbidities more prevalent in the LGBTQ+ community, including smoking, substance use disorder and HIV.

Overall, 39,632 (10%) of individuals within the cohort identified as LGBTQ+. Within that group, 38,528 (97%) identified as nonstraight and 4,431 (11%) identified as noncisgender.

Huo and colleagues found that 5.4% (n = 21,091) of the participants experienced adverse brain health outcomes, including 11,553 (45.8%) who experienced late-life depression, 6,605 (31.3%) cases of stroke and 2,933 (13.9%) with dementia.

Results showed that LGBTQ+ participants were more likely to experience an adverse brain health outcome in model 1 (OR = 1.15; 95% CI, 1.09-1.22), model 2 (OR = 1.24; 95% CI, 1.17-1.32) and model 3 (OR = 1.15; 95% CI, 1.08-1.22).

Secondary analyses based on model 3 — with similar results across models — showed that LGBTQ+ participants were 14% more likely to experience dementia (OR = 1.14; 95% CI, 1-1.29) and 27% more likely to experience late-life depression (OR = 1.27; 95% CI, 1.17-1.38) compared with straight cisgender participants, although the overall risk for stroke was not significantly increased (OR = 0.97; 95% CI, 0.87-1.07).

Subgroup analyses further showed that only transgender women had an increased risk for stroke (OR = 1.68; 95% CI, 1.04-2.7), with this group being particularly vulnerable to late-life depression (OR = 2.19; 95% CI, 1.4-3.44).

After matching by age in a sensitivity analysis, the risk for adverse brain health outcomes increased from 3.55% (95% CI, 3.37-3.73) to 4.71% (95% CI, 4.46-5) for LGBTQ+ participants, whereas it decreased from 5.55% (95% CI, 5.49-5.64) to 3.75% (95% CI, 3.68-3.82) for cisgender straight people, which indicates that age was a “major cofounder” in this association, according to researchers.

“The reasons for the observed disparities could be due to a variety of contributions from physical (eg, gender-affirming hormone therapy and violence), psychosocial (eg, discrimination, stigma, stress and depression) and systemic (eg, policy and legal protection and health care access) factors. These factors can impair brain health in various ways,” Huo and colleagues wrote.

They noted several limitations to this study, including a lack of investigation into the reasons behind the inequalities experienced by LGBTQ+ participants and potential sampling bias.

“In our cross-sectional study, sexual and gender minority persons had an increased risk of adverse brain health outcomes. Our findings underscore the need for further research focusing on the health care disparities affecting [this] community,” Huo and colleagues wrote.

Future research should investigate additional neurological outcomes and the causal factors of these disparities, they added.

Reference:

• Are gender and sexual identity linked to brain health? https://medicalxpress.com/news/2024-09-gender-sexual-identity-linked-brain.html. Published Sept. 25, 2024. Accessed Sept. 26, 2024.