Temporal and demographic trends in hypertension-associated breast cancer mortality in the United States: A CDC WONDER analysis (1999–2020).

e13097 Background: Hypertension is the most common comorbidity among breast cancer survivors and is independently associated with higher breast cancer specific mortality. However, population-level trends and disparities when both conditions co-occur remain poorly described. This study examined temporal trends, demographic disparities, and geographic variation in hypertension-associated breast cancer mortality in the U.S. Methods: Mortality data were obtained from the CDC WONDER Multiple Cause of Death database from 1999–2020. Deaths were included when both breast cancer (ICD-10 C50) and hypertensive disease (ICD-10 I10–I15) were listed as contributing causes among adults aged ≥55 years. Age-adjusted mortality rates (AAMRs) per 100,000 populations were calculated using the 2000 U.S. standard population. Temporal trends were assessed using Joinpoint regression to estimate annual percent change (APC) and average annual percent change (AAPC). Analyses were stratified by age, sex, race/ethnicity, urbanization level, census region, and U.S. state. Results: From 1999–2020, 107,759 deaths were attributed to breast cancer in the U.S., with AAMRs rising from 3.8 to 8.8 per 100,000. Joinpoint regression identified rapid increase 1999–2001 (APC 20.4%, 95% CI 9.77–30.0; p < 0.001), moderate rise 2001–2007 (APC 1.88%, 95% CI 0.04–4.52; p = 0.046), slight decline 2007–2018 (APC −0.59%, 95% CI −4.01–−0.05), and sharp increase 2018–2020 (APC 14.6%, 95% CI 7.7–19.9). Mortality was highest in adults ≥85 years (47 per 100,000 in 2020). Ages 55–64 showed rapid rise 1999–2003 (APC 12.5%, 95% CI 6.17–27.8; p < 0.01), stability 2003–2018, and sharp increase 2018–2020 (APC 20.8%, 95% CI 8.47–30.2; p < 0.001). Females had higher mortality than males (15.1 vs. 0.2), with male rates stable (APC 0.92%, 95% CI −0.72–2.86; p = 0.22). Female rates rose steeply 1999–2001 (APC 26.8%), moderately 2001–2008 (APC 1.92%), and sharply 2018–2020 (APC 15.5%). Non-Hispanic (NH) Black individuals had the highest AAMRs (13.8), NH Asian/Pacific Islander the lowest (4.7). NH White rates rose 1999–2001 (APC 26.8%), stable 2001–2018, then rose 2018–2020 (APC 12.8%). NH American Indian/Alaska Native rates rose steadily (APC 2.48%). States with age-adjusted mortality rates above the 90th percentile included District of Columbia (12.2), Nebraska (11.2), Mississippi (11.1), Oklahoma (11.1), and Ohio (10.6). Nonmetro (10.0) and micropolitan (9.6) areas had higher mortality. Large central metros rose rapidly 1999–2001 (APC 20.8%), modestly through 2010, declined 2010–2018, and rose again 2018–2020 (APC 12.6%). Conclusions: Hypertension-associated breast cancer mortality has risen over the past two decades, especially among older women, NH Black populations, and residents of rural or high-burden states which underscore the need for targeted public health interventions to reduce disparities.