Sexual orientation, health risk factors, and physical functioning in the Nurses' Health Study II

To examine associations between sexual orientation and breast cancer risk factors, cardiovascular disease (CVD) risk factors, mental health status, and health-related functioning.

We compared participants in the Nurses' Health Study II (NHSII) reporting a lesbian or bisexual orientation with those reporting a heterosexual orientation, with heterosexuals serving as the reference group for all comparisons. Prevalence of health behaviors and conditions was adjusted for differences in the distribution of age, ancestry, and region of residence by standardizing to the distribution of the overall cohort. Multivariate prevalence ratios were calculated to compare lesbians and bisexuals with heterosexuals using binomial regression with the log link function. Means of health conditions were measured using continuous scales standardized to the distribution of the overall cohort. Differences in means comparing lesbians and bisexuals with heterosexuals were tested by multivariate linear regression. All comparisons were adjusted for age, ancestry, and region of residence.

Based on information from 90,823 women aged 32-51 in 1995, those reporting a sexual orientation of lesbian (n = 694) had a higher prevalence of risk factors for breast cancer, including nulliparity and high daily alcohol intake, compared with heterosexual women. Lesbians also had a higher prevalence of several risk factors for CVD, including higher body mass index (BMI) and elevated prevalence of current smoking. Lesbians were more likely to report depression and the use of antidepressants. Key results for health risk factors were similar for lesbians and bisexual women (n = 317).

Lesbian and bisexual women were found to have a higher prevalence of several important risk factors for breast cancer, CVD, and poor mental health and functioning outcomes. Most of these risk factors are modifiable, and appropriate interventions could play an important role in improving the health status of lesbian and bisexual women.