National Trends and Disparities in Cancer Mortality Among Individuals With Alzheimer's Disease and Related Dementias in the United States, 1999–2020

ABSTRACT As population aging accelerates, the coexistence of cancer and Alzheimer's disease and related dementias (ADRD) is becoming increasingly common. While each condition independently contributes to mortality, national trends in cancer‐related deaths occurring alongside ADRD—and their demographic and geographic disparities—remain poorly defined. We conducted a retrospective population‐based analysis using mortality data from the CDC WONDER (1999–2020). Deaths listing both malignant neoplasms (ICD‐10: C00–C97) and ADRD (F01, F03, G30) were identified. Age‐adjusted mortality rates (AAMRs) per 100,000 population were calculated using the 2000 U.S. standard population. Temporal trends were assessed using joinpoint regression to estimate annual percent change (APC) with 95% confidence intervals. Stratified analyses by sex, race, region, and state were performed to evaluate disparities. A total of 89,514 deaths with concurrent cancer and ADRD were identified. The AAMR more than doubled from 2.0 per 100,000 in 1999 to 4.6 in 2020, peaking in 2012. Overall mortality increased significantly from 1999 to 2009 (APC 9.11%, p < 0.05), followed by stabilization. Sex‐specific analyses showed continued increases among females, whereas males demonstrated a significant decline after 2010. By race, Black individuals experienced a steeper early rise followed by a significant decline, while trends among White individuals plateaued after 2009. Regionally, the South exhibited a significant post‐2010 decline, whereas other regions stabilized. Marked state‐level variation was observed, with the highest rates in the Midwest and the lowest in the Southwest. Cancer mortality with concurrent ADRD increased substantially in the early 2000s, followed by divergent trends across demographic and geographic subgroups. Persistent disparities highlight the need for integrated oncologic and cognitive care strategies and targeted public health interventions addressing inequities in aging populations.