Breast Cancer Risk, Screening, and Prevalence Among Sexual Minority Women: An Analysis of the National Health Interview Survey.

Purpose: Sexual minority women (SMW) may have a different distribution of breast cancer risk factors than their heterosexual peers. Epidemiologic studies of breast cancer in SMW have been limited, and many use only proxy variables to identify SMW in data sets, introducing selection bias. We utilized National Health Interview Survey (NHIS) data to compare breast cancer risk factors, screening, and prevalence between SMW and non-SMW. Methods: We identified female respondents to the NHIS from 2013 to 2017, selected women >= 40 years old and stratified by sexual orientation. We compared demographics and health maintenance variables and prevalence of breast cancer diagnosis between groups and performed a multivariable analysis of breast cancer risk. Results: Of 58,378 women >= 40 years old, 1162 (2.0%) were identified as SMW. SMW were younger and more likely to use tobacco and alcohol, be younger at menarche, and be nulliparous. SMW also reported less preventive care, and despite reporting equivalent rates of mammography, were more likely to obtain mammograms due to an identifiable problem and not simply for screening purposes. Prevalence of breast cancer was similar between SMW and non-SMW (4.7% vs. 5.0%, p = 0.67), and SMW status was not associated with breast cancer diagnosis on univariate and multivariable logistic regression (p = 0.14 and p = 0.07, respectively). Conclusion: Despite finding no difference in breast cancer prevalence between SMW and non-SMW, there was evidence for differences in the utilization of breast care. Further studies of breast cancer incidence, characteristics (including subtype and stage), treatment, and survival for SMW are needed.