Breast Cancer Mortality's Association with Sexual Orientation

Our objective is to test disparities in breast cancer mortality by sexual orientation. Using an ecological approach that links SEER breast cancer mortality data with Census 2000 data, we test the hypothesis of higher breast cancer mortality in areas with more presumed lesbians. From the Census 2000 data on female same-sex partnered households, we derive a measure of sexual minority women density (SMWD) for each of the 215 counties covered by SEER 12. We test the association of SMWD with breast cancer mortality using multivariable Poisson regression models that control for age, race, and socioeconomic status. We confirm our hypothesis as we find a significant positive association between SMWD and breast cancer mortality. This relationship remains significant even after controlling for other factors, known to have an association with mortality, such as poverty or race. This ecological approach compensates for the absence of cancer surveillance by sexual orientation. The results suggest a disparity in breast cancer mortality due to sexual orientation. The causes for this disparity need to be identified by future studies.