Mortality rate disparities in breast cancer with obesity: Insights from CDC WONDER analysis of two decades.

e13030 Background: Obesity is a significant risk factor for breast cancer, influencing its incidence and progression, and contributing to mortality. Analyzing two decades of CDC WONDER data provides insights into the mortality disparities associated with obesity in breast cancer patients. Methods: Death certificate data from the CDC WONDER database for adults aged ≥25 years (1999–2020) were analyzed. Crude mortality rates (CMRs) and age-adjusted mortality rates (AAMRs) per 100,000 persons were calculated. Temporal trends were assessed using annual percent change (APC) and average annual percent change (AAPC) via Joinpoint regression. Results: From 1999 to 2020, 1,895 individuals (female: 1,840; male: 55) died from breast cancer with obesity in the USA, with an overall AAMR of 0.03 (95% CI [0.03–0.03]). AAMRs showed an upward trend (AAPC: 5.77, 95% CI [3.23–8.37]; p<0.00001). Trends rose from 1999–2017 (APC: 2.80, 95% CI [0.77–4.86]; p=0.009) and sharply increased from 2017–2020 (APC: 25.47, 95% CI [9.24–44.12]; p=0.003).AAMRs were higher for women (0.07, 95% CI [0.07–0.07]) than men (0.0, 95% CI [0.0–0.0]), with identical APC/AAPC values for females (4.95, 95% CI [3.35–6.58]; p<0.005). Non-Hispanic (NH) African Americans had the highest AAMRs (0.09, 95% CI [0.08–0.10]), followed by NH Whites (0.02, 95% CI [0.01–0.03]) and Hispanic Whites (0.02, 95% CI [0.01–0.03]). NH Asians or Pacific Islanders (2.2, 95% CI [2.2–2.3]) and NH American Indians or Alaska Natives (2.9, 95% CI [2.7–3.1]) had the lowest AAMRs.Regionally, Nebraska had the highest AAMR (0.08), followed by Colorado, Oklahoma, and Oregon (0.06). While all regions shared an AAMR of 0.03 (95% CI [0.03–0.04]), the Midwest had the highest CMR (0.05, 95% CI [0.04–0.05]), followed by the South (0.04), West (0.04), and Northeast (0.03). Conclusions: Targeted interventions are needed to reduce breast cancer-related mortality with obesity, particularly among females, African Americans, and high-burden states. Efforts should focus on improving healthcare access, promoting screening, fostering lifestyle changes, addressing disparities, and ensuring culturally competent care to mitigate the burden in these vulnerable populations.