Regional and demographic trends in mortality from breast cancer and respiratory diseases in United States from 1999-2019: A retrospective analysis.

e13779 Background: Breast cancer and respiratory diseases are significant contributors to global morbidity and mortality, particularly in vulnerable populations. This study evaluates age-adjusted mortality rates (AAMRs) associated with these conditions in the United States from 1999 to 2020, focusing on gender, ethnic, geographic, and urban-rural disparities to uncover emerging trends and areas for targeted healthcare improvement. Methods: Mortality data were extracted from the Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiological Research (CDC WONDER) database from 1999 to 2020. Age-adjusted mortality rate (AAMR) and Crude Mortality Rate (CMR) per 100,000 individuals and annual percent changes (APC) with 95% Confidence Intervals (CI) were calculated. Results: From 1999–2020, 175,596 deaths from breast cancer and respiratory diseases were reported in the U.S., with AAMR decreasing slightly from 2.8 to 2.6 (AAPC: -0.51; 95% CI: -0.97 to -0.06). However, AAMR rose from 2010 to 2020 (APC: 1.15; 95% CI: 0.39 to 1.93). Females had consistently higher AAMRs (1999: 4.6 vs. 0.1 males; 2020: 4.7 vs. 0.1 males), with a decline from 1999–2007, stabilization until 2016, and an increase from 2014–2020. Ethnic disparities revealed higher AAMRs in Black individuals, rising from 3.0 to 3.7 (APC: 6.84) between 2017–2020. Alaska Natives showed declines, while Asians and Whites experienced variable trends. Rural areas exhibited a sharper AAMR increase (2.3 to 2.8; APC: 6.06) than urban areas (2.2 to 2.6; APC: 3.76) from 2017–2020. Geographically, the Midwest and South saw the most pronounced increases post-2016. Conclusions: Mortality trends for breast cancer and respiratory diseases showed initial declines but significant recent increases, especially among females, Black populations, rural areas, and the Midwest and South. These disparities highlight the urgent need for targeted public health interventions.