In a newly published study involving 94,250 women across the United States, researchers found that lesbian and bisexual (LB) women were more likely than heterosexual women to develop type 2 diabetes during the course of the 24-year study follow up.
The co-authored study, led by Heather L. Corliss, a professor at San Diego State University's Graduate School of Public Health, investigated incidence of type 2 diabetes in lesbian and bisexual women and heterosexual women in a large, longitudinal U.S. cohort.
Corliss and her team members released their findings in "Risk of Type 2 Diabetes Among Lesbian, Bisexual, and Heterosexual Women: Findings from the Nurses' Health Study II," an article published this month in Diabetes Care.
For the study, the team analyzed survey results dating back to 1989 from women participating in the Nurses' Health Study II, which is one of the largest investigations into the risk factors for major chronic diseases in women.
All women were between the ages 24 to 44 at the start of the study and were assessed for a diagnosis of type 2 diabetes every other year to identify incidence, from 1989 to 2013. The women self-identified their sexual orientation and, of the participants, 1,267 identified as lesbian or bisexual and 92,983 identified as heterosexual. Diabetes was assessed by self-reported clinician diagnosis.
Corliss and her colleagues found over that 24-year time period that lesbian and bisexual women had a 27 percent higher risk of developing type 2 diabetes than heterosexual women. In 2013, 6,399 women had developed type 2 diabetes with lesbian and bisexual women having a 22 percent greater risk of developing type 2 diabetes.
The team also found that lesbian and bisexual women developed type 2 diabetes at younger ages than heterosexual women, and that a higher body mass index in lesbian and bisexual women was an important contributor to disparities found.
"Given the significantly higher risk of developing type 2 diabetes before age 50 years among LB women, and their potentially longer duration of living with type 2 diabetes, LB women may also be more likely to experience complications compared with heterosexual women," the researchers wrote in the paper.
Corliss explained that her team carried out the study because previous research on risk of type 2 diabetes among lesbian and bisexual women has been inconclusive - some studies found differences between heterosexual and lesbian and bisexual women, while other studies did not find differences.
"Despite inconclusive findings, there is a reason to suspect that LB women may have disparities in chronic physical health conditions, including type 2 diabetes, because they are more likely than heterosexual women to have risk factors such as obesity, tobacco smoking, heavy alcohol drinking and stress-related exposures," the team explained.
Stress is an important consideration, here. The team noted that stress related to discrimination, violence victimization and psychological distress, were reportedly higher for lesbian and bisexual women, and these factors may contribute to higher rates of health-related issues for those women.
"Although it is important to address behavioral factors such as physical activity, sedentary behavior and dietary intake, focusing on these factors alone may not be sufficient to eliminate LB women's disparities in chronic disease," the team explained.
Corliss and her colleagues emphasize that enhanced public health and clinical efforts to prevent, detect and manage obesity and type 2 diabetes among lesbian and bisexual women -- along with improved access to care -- are crucial needs.
The team is also calling for expanded research into sexual orientation-related differences in disease management and on the overall health of lesbian and bisexual women.
Such improved knowledge is "vital to understanding the implications of disease on their subsequent health risks and prognosis," the team explained.
Other authors on the study are: Nicole A. VanKim of the Department of Biostatistics and Epidemiology at the University of Massachusetts Amherst; Hee-Jin Jun of SDSU's Graduate School of Public Health; S. Bryn Austin, Molin Wang and Frank B. Hu, all of the Brigham and Women's Hospital; and Biling Hong of the Harvard T.H. Chan School of Public Health.