Abstract 3662: Association of US county-level social vulnerability index (SVI) with breast and colon cancer screening rates
Authors: Mehta Akhil , Lau Eric , Nagaraj Gayathri , Mirshahidi Hamid 
Published: June 2022

Introduction: Whether social determinants of health (SDOH) affect US breast and colon cancer screening rates remains unclear. That said, in 2011 the CDC began recording a social vulnerability index (SVI) for all US counties. SVI was designed to capture four SDOH: socioeconomic status (SES), household composition and disability, minority status and language, and housing type and transportation. This retrospective study sought to determine the association of county-level SVI with breast and colon cancer screening rates.

Methods: We used publicly available data from the CDC 2018 SVI database to collect SVI scores for every US county. SVI scores range from 0.1 to 1. A lower score indicates low vulnerability, while a higher score suggests high vulnerability. SVI scores were merged with publicly available data from the 2018 Behavioral Risk Factor Surveillance System (BRFSS) and National Health Interview Survey (NHIS) containing county modeled estimates for breast and colon cancer screening rates. Counties were then divided into &lt; 50th percentile and &gt;= 50th percentile for breast and colon cancer screening. SVI scores and their four SDOH were compared between groups. Statistical significance between groups was assessed at an alpha less than 0.5. Linear regression was used to identify the association between high county-level SVI and the probability of being &gt;= 50th percentile in breast and colon cancer screening.

Results: This study involved 3,109 counties. Compared to counties &gt;= 50th percentile in breast cancer screening (n = 1543), those &lt; 50th percentile (n = 1566) were significantly worse off in SES (0.60 ± 0.27 vs. 0.41 ± 0.27), household composition and disability (0.58 ± 0.28 vs. 0.42 ± 0.28), minority status and language (0.51 ± .30 vs. 0.49 ± .28), housing type and transportation (0.53 ± 0.29 vs. 0.46 ± 0.28), and overall SVI (0.58 ± 0.28 vs. 0.42 ± 0.27) (p &lt; .0001). Likewise, compared to counties &gt;= 50th percentile in colon cancer screening (n = 1548), those &lt; 50th percentile (n = 1561) were also significantly worse off in SES (0.63 ± 0.27 vs. 0.38 ± 0.25), household composition and disability (0.59 ± 0.27 vs. 0.41 ± 0.27), minority status and language (0.54 ± .30 vs. 0.45 ± .27), housing type and transportation (0.54 ± 0.29 vs. 0.46 ± 0.28), and overall SVI (0.61 ± 0.28 vs. 0.39 ± 0.27) (p &lt; .0001). High SVI counties compared with low SVI counties were significantly less likely to be &gt;= 50th percentile in breast cancer and colon cancer screening, OR 0.24 (95% CI 0.20 - 0.29) and 0.14 (95% CI 0.12 - 0.18). Finally, county-level SVI percentile correlated negatively with breast and colon cancer screening rates, Pearson coefficient -0.35 and -0.46.

Conclusions: This study highlights the significant impact of US county-level SVI on breast and colon cancer screening rates, signaling the need for more effective intervention strategies and allocation of resources to help improve SDOH for our country's most vulnerable citizens.

Citation Format: Akhil Mehta, Eric Lau, Gayathri Nagaraj, Hamid Mirshahidi. Association of US county-level social vulnerability index (SVI) with breast and colon cancer screening rates [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3662.