Study Examines Dementia Epidemiology in the LGB Population

CHICAGO—The first large-scale analysis of dementia prevalence among sexual minorities found a rate of 8% in adults age 60 or older who are lesbian, gay, or bisexual (LGB), according to research presented at AAIC 2018.

The crude dementia prevalence was lower than the 9% prevalence among a heterosexual comparator group. Subjects in the LGB group, however, were younger, more likely to be male, and more likely to have a college education, compared with subjects in the heterosexual group, said Jason Flatt, PhD.

Jason Flatt, PhD

The analysis of a large California health care database is the first step in learning more about dementia in this diverse population, said Dr. Flatt, Assistant Professor at the Institute for Health & Aging at the University of California, San Francisco.

A Gap in the Literature

Between two million and three million people age 60 or older in the United States identify as LGB. “With the continued aging of our entire population, we expect this number to increase to about six million by 2040,” Dr. Flatt said. “Given the gaps in collection of sexual orientation and gender identification, we have not been able to look at this issue before.”

Sexual minorities may face unique dementia risks. They are less likely to marry and have children than are heterosexuals, and twice as likely to live alone. “They often have little or no caregiver support, and are likely to have experienced stigma, discrimination, trauma, and high lifelong stress,” he said. These experiences make the LGB population less likely to seek out medical care. “All of these things impact health over the life course,” he said.

To examine the prevalence of dementia and potential risk factors in a sample of LGB older adults, Dr. Flatt and his colleagues analyzed data from the Kaiser Permanente Research Program on Genes, Environment, and Health. Their study examined dementia prevalence and comorbidities among 4,337 LGB subjects and 195,264 heterosexual subjects aged 60 or older. Dementia diagnoses occurred between 1996 and 2015, and the mean follow-up time was nine years. A quarter of the LGB sample identified as lesbian, 37% identified as gay men, and 38% identified as bisexual. Depression was more common in the LGB group (35% vs 28%), as was posttraumatic stress disorder (1.9% vs 1%). Both are well-documented risk factors for dementia.

The LGB group had a younger mean age, compared with the heterosexual group (69 vs 71). In addition, a greater percentage of LGB subjects identified as male (63% vs 44%) and had a college education (62% vs 40%).

Other risk factors such as hypertension, stroke, and heart disease did not significantly differ between the groups. Dr. Flatt and his associates plan to examine midlife obesity, physical inactivity, and low educational attainment in a future analysis.

Depression Nearly Tripled the Risk

A dementia diagnosis occurred in 343 subjects (7.9%) in the LGB group and in 18,060 subjects (9.2%) in the heterosexual group.

Higher education did not seem to be as protective in the LGB population, Dr. Flatt said.

In a regression analysis that adjusted for age and education, depression almost tripled the risk of dementia among sexual minorities (odds ratio, 2.7). Depression was also a significant dementia risk factor for heterosexual subjects (odds ratio, 2.5).

These initial findings highlight the need for more research into this population, Dr. Flatt said.

“We need to provide more LGB-affirming health care services, and this means training health care providers to meet these needs,” he said. Such efforts might include improved community outreach that could result in earlier detection and treatment, as well as training medical staff to provide more culturally sensitive care.

—Michele G. Sullivan