Cancer
Breast cancer prevalence among privately insured same-sex female couples in the US Kodiak RS Soled* Kodiak Soled Isa Berzansky Landon Hughes Tonia Poteat Shail Maingi Alexis Miranda Aimee K Huang Brittany M Charlton
Background: Female individuals with same-sex (SS) partners are more likely than those with different-sex (DS) partners to have breast cancer risk factors, yet little is known about breast cancer prevalence due to prior data limitations.
Methods: We used 2016–2022 data from the Merative MarketScan Research Database, which includes paid insurance claims and healthcare encounter data on enrollees who receive employer-sponsored healthcare. We identified breast cancer cases using International Classification of Disease-10 codes for malignant neoplasms and carcinoma in situ of the breast. Ongoing analyses include weighted and unweighted unadjusted period prevalence rate (PPR) ratios comparing female enrollees with SS vs DS partners. Age-specific comparisons are also underway using the NCI’s SEER*Stat software to report age-standardized PPR.
Results: Between 2016–2022, female enrollees with a DS partner totaled 10,501,932 compared to 214,095 with a SS partner. We identified breast cancer cases among 243,587 enrollees with a DS partner and 3,375 enrollees with a SS partner. Overall, we found that the PRR among enrollees with a DS partner was 46% greater than those with a SS partner (PRR: 1.46, p<0.001). When stratifying by age, we found the PPR among enrollees with a DS partner compared to a SS partner to be: 1.30 (p=0.099) among those <29 years old, 1.42 (p<0.001) among those 30 – 49 years old, and 1.20 (p<0.001) among those 50 – 69 year olds. Weighted and adjusted results are forthcoming.
Conclusions: Higher breast cancer PPR among enrollees with DF compared to SS partners may be explained by data biases (e.g., private insurance, partnered individuals) as well as survivorship bias among enrollees with SS partners — namely that cancer may be more advanced due to delayed screening and care and consequently not living as long. Improved data collection on cancer staging and sexual orientation is essential to understand if population-level breast cancer inequities persist.