Social vulnerability and cancer-related mortality among U.S. counties, 2013 to 2019.

Abstract

162 Background: Substantial differences exist among US counties with regards to cancer-related mortality. Social determinants of health (SDOH) can predispose underserved communities to poor cancer outcomes. We investigated the impact of county-level social vulnerability on age-adjusted cancer mortality rates (AAMRs). Methods: We linked cancer-related deaths across US counties from 2013 to 2019 in the CDC WONDER database to county-level Social Vulnerability Index (SVI) data from the CDC/ATSDR. Scores for overall SVI and its 4 subcomponents (socioeconomic status; household composition and disability; minority status and language; housing type and transportation) were calculated using 15 SDOH attributes. These were presented as percentile rankings by county and classified into quartiles based on their distribution among US counties (1st [least vulnerable] = 0 - 0.25; 4th [most vulnerable = 0.75 - 1.00]). AAMRs per 100,000 individuals across US counties were compared between 1st and 4th SVI quartiles using robust linear regression models with a log scale. Results: There were 4,107,273 deaths with overall AAMR 173 per 100,000 individuals. Highest AAMRs were noted among older adults > 65 years, men, non-Hispanic Black, and rural counties. AAMRs increased proportionally when moving from least to most vulnerable counties. Counties in 4th SVI quartile had 20% higher AAMRs compared to 1st SVI quartile (rate ratio; RR 1.08, 95% CI [1.08, 1.09], p < 0.001). This was pronounced for ages 45-65 (42% increase; RR 1.21, 95% CI [1.12 – 1.24]), Hispanic race (26% increase; RR 1.11, 95% CI [1.06, 1.16]), and rural counties (21% increase; RR 1.17, 95% CI [1.15, 1.19]). Increase in AAMR between 1st and 4th SVI quartile from vulnerable socioeconomic status was most pronounced in rural counties (RR 1.17; 95% CI [1.15, 1.2]), women (RR 1.17; 95% CI [1.15, 1.2]) and ages 45-65 (RR 1.15; 95% CI [1.09, 1.14]). Vulnerable household composition/disability was most pronounced for rural residents (RR 1.12; 95% CI [1.09, 1.14]), and housing/transportation barriers for Hispanic individuals (RR 1.15; 95% CI [1.09, 1.21]). Conclusions: This study highlights the most socially vulnerable US counties have higher cancer mortality rates than the least vulnerable US counties. Furthermore, non-Hispanic blacks, older adults, and rural counties face highest risks of health inequities. Our findings inform ongoing congressional deliberations on transportation, telehealth, and rural infrastructure to achieve geographic parity.[Table: see text]