Beyond geography: The intersecting impact of rurality, race, and depression on breast cancer survival.

Abstract

11137 Background: Rural–urban disparities in breast cancer outcomes are well-documented, with rural populations typically experiencing worse survival due to limited access to screening and specialty care. However, the role of integrated healthcare systems in mitigating these disparities and the impact of psychosocial factors, such as depression, on survival remain underexplored. This study evaluated the survival outcomes of breast cancer patients treated within an integrated, academic health system, focusing on the intersecting effects of geographic residence, race, and antidepressant therapy. Methods: We conducted a retrospective cohort study of 6,788 female breast cancer patients diagnosed between 2014 and 2024 at MUSC-affiliated facilities in urban and rural South Carolina. Data on patient demographics, cancer stage, hormone receptor status, depression diagnosis, and antidepressant use were extracted from electronic medical records. We used Kaplan-Meier survival analysis with log-rank tests and multivariable Cox proportional hazards models to assess the association of geographic location, race, and antidepressant use with overall survival, while adjusting for clinical and demographic confounders. Results: Contrary to national trends, rural patients demonstrated superior overall survival compared to urban patients (5-year survival: 92.1% vs. 85.3%, p < 0.001). In a multivariable model, rural residence was an independent protective factor (HR = 0.72, 95% CI: 0.61–0.85, p < 0.001). Antidepressant treatment was also associated with significantly improved survival (HR = 0.78, 95% CI: 0.65–0.93, p = 0.006). This survival benefit was consistent across urban and rural subgroups. While African American race showed a borderline increased risk of mortality (HR = 1.18, 95% CI: 0.98–1.42, p = 0.081), the rural survival advantage was maintained within both African American and non-African American subgroups. Triple-negative breast cancer (TNBC) was an independent and significant predictor of mortality (HR = 1.34, 95% CI: 1.15–1.57, p < 0.001), and was more prevalent in the urban cohort. Conclusions: Our findings suggest that a coordinated, academic-affiliated care model can effectively address geographic barriers to care. The study also highlights the critical role of psychosocial health, demonstrating that antidepressant therapy is an independent predictor of improved survival, reinforcing the need for integrated mental health support in oncology. Furthermore, the higher prevalence of aggressive triple-negative breast cancer in the urban cohort, coupled with the potential for the urban facilities to receive more complicated referrals, may contribute to the observed urban survival disadvantage, underscoring the interplay of tumor biology and patient referral patterns within integrated systems.