Type 2 diabetes: Sexual orientation may influence risk

A large-scale, 24-year-long study focuses on the incidence of type 2 diabetes among lesbian and bisexual women. It found that they are almost a third more likely to develop it.

The National Institutes of Health (NIH) estimate that more than 30 million people in the United States live with type 2 diabetes.

Many of the risk factors for diabetes are lifestyle habits that can be changed. Being physically active, eating right, and trying to maintain a healthy weight can all lower the risk.

Some other factors, such as ethnicity or genes, are hard to change, but being aware that you may be at risk is still useful for preventing the metabolic disease.

For instance, African Americans, Mexican Americans, American Indians, Native Hawaiians, Pacific Islanders, and Asian Americans are known to be at a higher risk of developing type 2 diabetes.

People who have relatives with diabetes or a family history are also predisposed to the condition, as are people who have heart disease or have had a stroke.

New research suggests that sexual orientation might also be a risk factor worth adding to the list.

The new study — which was led by Heather L. Corliss, a professor at San Diego State University's Graduate School of Public Health in California — suggests that women who identify as lesbian or bisexual are at an increased risk of developing type 2 diabetes.

The findings were published in the journal Diabetes Care.

Young lesbian and bisexual women at risk

To study the incidence of type 2 diabetes among gay and bisexual women, Corliss and colleagues studied 94,250 women who had taken part in the Nurses' Health Study II — which is one of the largest longitudinal studies to ever investigate risk factors for major chronic conditions among women.

Of the study participants, 1,267 identified as lesbian or bisexual. The women were aged between 24 and 44 at the beginning of the study in 1989. In 1989–2013, every 2 years, the women were clinically assessed for diabetes.

Overall, the study discovered that lesbian and bisexual women were 27 percent more likely to develop type 2 diabetes in the 24-year study period.

The study also revealed that gay and bisexual women tended to develop the condition earlier on than heterosexual women. Additionally, a higher body mass index (BMI) seemed to mediate this correlation.

Stress may explain diabetes risk

As the researchers explain, "Given the significantly higher risk of developing type 2 diabetes before age 50 years among [lesbian and bisexual] women, and their potentially longer duration of living with type 2 diabetes, [these] women may also be more likely to experience complications compared with heterosexual women."

Corliss and team also highlight the importance of stress in preventing chronic disease in this group of women.

"[T]here is a reason," they go on to explain, "to suspect that [lesbian and bisexual] 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 study authors suggest that the discrimination and psychological distress that these women may be prone to could take a toll on their health and raises the risk of various health problems. Corliss and colleagues conclude:

"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 [lesbian and bisexual] women's disparities in chronic disease."