County-Level Urbanization and Cardiovascular Death in Patients With Cancer.

Context: Cardiovascular death (CVD) is a leading cause of mortality in patients with cancer, with sociodemographic factors such as urbanization influencing outcomes.

Objective: To examine the impact of county-level urbanization on CVD mortality in patients with cancer in the United States from 1999 to 2020.

Design: Retrospective cross-sectional analysis using CDC WONDER mortality data.

Setting: US counties categorized as rural or urban based on the 2013 NCHS Urban-Rural Classification Scheme.

Participants: Patients with cardiovascular disease (ICD-10: I00-I78) and comorbid cancer (ICD-10: C00-C97), spanning all U.S. counties from 1999 to 2020.

Main outcome measures: Age-adjusted mortality rates (AAMRs) per 100 000 population and rural-to-urban rate ratios (RRs) with 95% confidence intervals.

Results: The cumulative rural-to-urban RR for CVD in patients with cancer was 1.11 (95% CI: 1.10-1.11), increasing from 1.00 in 1999 to 1.20 in 2020 (β = 0.009, P < .001). Rural AAMRs were higher across demographic groups, including males (12.85 vs 11.62 per 100 000), females (6.08 vs 5.58), Black individuals (9.76 vs 9.64), and White individuals (8.79 vs 7.94). Rural Black populations showed a rising RR from 0.85 in 1999 to 1.04 in 2020 (β = 0.005, P = .01). Hispanic populations exhibited lower rural mortality, with a stable RR (0.93, P = 1.0). The most common CVD cause was ischemic heart disease (53.93% of rural and 55.9% of urban deaths).

Conclusions: An increasing rural-to-urban disparity in CVD mortality among cancer patients highlights the role of urbanization in health inequities. Interventions targeting rural health care access and socioeconomic disparities are essential to address this growing gap.