Abstract PO5-10-02: Neighborhood deprivation index and time to initiation in patients with metastatic breast cancer

Abstract Background Cyclin-dependent kinase 4 and 6 inhibitors (CDKi) are first-line therapy for patients with estrogen-positive (ER+) metastatic breast cancer (MBC). The accessibility, usability, and outcomes according to demographic factors have not been well studied in real world practice. Methods Retrospective review of patients with ER+ MBC prescribed first line CDKi therapy at a large NCI-designated cancer center from January 2015 through December 2022. Patient records were abstracted for outcomes including 1) time from CDKi prescription to drug initiation (TTI), 3) time from CDKi initiation to progression, and 3) time from CDKi initiation to death/or 6/30/2022. Patient variables collected were: patient age (continuous), race (patient self-report – Black, White, Other), partner status (Married, Not married), Insurance type (Medicare, Medicaid, Private); Mean BMI; Number of comorbidities (5 categories). Neighborhood deprivation index (NDI) was determined from the patient’s address with higher scores indicating more deprivation. Descriptive, comparative, and correlational statistics were used. Results A total of 173 patients were included in the analysis. Mean age – 63.1, (SD 12.7, range 24-94); race – White n=157, Black n=16; marital status – Married n=102, Not married n=71; mean NDI – 61.0 (SD 23.7, range 6-100); mean BMI – 28.9 (SD 6.9, range 16-48); number of comorbidities – 0 n=35, 1-2 n= 35, 3-4 n = 55, 5-6 n = 20, 7+ n = 28; insurance type – Medicare n = 115, Medicaid n = 21, Private n = 37. TTI: the median TTI was 14 days. There were no statistically significant differences in TTI based on age, race, NDI, or other demographic variables. Time to progression: in the multivariate model, younger age at diagnosis and Medicaid insurance were associated with shorter time to progression. Overall survival: not married, younger age at diagnosis, and Medicaid insurance were associated with shorter overall survival. Discussion Demographic factors are associated with diverse outcomes of MBC therapy, not attributed to delay in CDKi treatment initiation. Personalization of support during MBC illness according to risk factors for worse outcomes may help to equalize incomes. Citation Format: Sneha Rajendran, Dianxu Ren, Marina Petruzzi, Margaret Rosenzweig. Neighborhood deprivation index and time to initiation in patients with metastatic breast cancer abstract. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-10-02.