Correlation between County-Level Surgeon Density and Mortality from Colorectal Cancer

Abstract

Purpose: We aimed to explore the effect of county-level general surgeon (GS) and colorectal surgeon (CS) density on colorectal cancer (CRC) mortality and to identify additional county characteristics associated with outcomes.

Methods: Using data from the Area Resource File, US Census, and National Cancer Institute, we developed multivariate regression models to determine the effect of density of GS and CS on CRC death between 2005 and 2009 while controlling for CRC incidence, county demographics, and other socioeconomic factors.

Results: In total, we included 1767 counties: Mean CRC incidence and death rates were 64.9 and 19.9 %, respectively. In this cohort, 45 % were metropolitan areas. Mean GS and CS densities were 7.2 and 0.15 per 100,000 people, respectively. Counties with at least 1 GS had a statistically significant decrease in CRC-specific mortality (beta coefficient -0.18, p < 0.001). Increasing GS density beyond 8 per 100,000 people did not result in any further meaningful reductions in mortality. The presence of at least 1 CS at the county-level was not associated with differences in CRC mortality (beta coefficient -0.021, p = 0.37). Metropolitan counties and a larger percentage of individuals who were <65 years old were associated with decreased CRC mortality. Conversely, a higher proportion below the poverty line was correlated with a significant increase in CRC mortality.

Conclusion: Unlike CS, the presence of GS at the county-level was associated with lower CRC mortality. However, increasing GS density beyond a certain point did not result in further meaningful reductions in mortality. A balanced strategy of distributing the surgical workforce across all counties can result in population-based improvements in CRC outcomes.

Keywords: Colorectal cancer; County-level; Mortality; Surgeon density.