Abstract TP147: Trends in Stroke-Related Mortality Among Adults with Malignant Breast Neoplasm in the United States, 1999–2020

Background: While advances in cancer therapy have reduced breast cancer–specific mortality, stroke-related mortality in this population remains underexplored. Understanding national trends may reveal gaps in survivorship care and cardiovascular risk management. Methods: We queried the CDC WONDER Multiple Cause of Death database from 1999 to 2020 for individuals aged ≥25 years with both malignant breast neoplasm (ICD-10: C50) and stroke (ICD-10: I64) listed as causes of death. Age-adjusted mortality rates were calculated per 100,000 population. Joinpoint regression was used to assess temporal trends and estimate annual percent change (APC), average annual percent change (AAPC), and inflection points. Results: A total of 23,421 stroke-related deaths were identified in individuals with malignant breast neoplasms. Overall, stroke-associated mortality declined significantly (AAPC: –4.22%, 95% CI: –4.66 to –3.78; p < 0.000001). Among females, mortality declined until 2018 (APC: –4.22%; p < 0.0001), followed by a non-significant rise (APC: +6.69%; p = 0.36). Older adults, particularly those aged ≥85 years, experienced the most consistent and steepest decline (AAPC: –4.56%; p < 0.000001), while trends among those aged 55–74 were mixed but generally decreasing. In the Black population, mortality declined from 1999 to 2015 (APC: –4.89%; p < 0.000001), followed by a non-significant increase through 2020. Throughout the study period, Black individuals consistently had higher age-adjusted mortality rates than White individuals. When stratified by geographic region, the Northeast exhibited the steepest decline (AAPC: –4.62%; p < 0.0001). By urbanization category, large central metropolitan areas also showed a substantial and sustained reduction (AAPC: –4.07%; p < 0.0001). Conclusions: Stroke-related mortality among individuals with malignant breast neoplasms has declined over the past two decades. However, recent plateaus and persistent differences by race, region, and age suggest that cerebrovascular risk is not being addressed equally. These findings highlight the importance of integrating cerebrovascular risk assessment into routine cancer care, particularly for high-risk groups.