Disparities in colorectal cancer mortality for rural populations in the United States: Does screening matter?

Introduction: Rural compared to urban populations in the US have increased colorectal cancer (CRC) incidence with known disparity in screening rates and mortality. We hypothesize that rural-urban disparities are different at a regional level. Methods: We assessed screening rates according to the 2016 Behavioral Risk Factor Surveillance System guidelines using state and city-level data for county level estimates and correlating with county CRC mortality data from the National Cancer Institute. We used multivariable modeling to examine associations between rurality, screening rates, and mortality. Results: Highest screening rate states had the smallest urban-rural disparities; lowest screening rate states had the largest disparities. Percent screened and urban-rural classification correlated significantly with mortality. Rural counties experienced ∼5 more deaths per 100,000 population even controlling for screening rates. Conclusions: National urban-rural disparities in CRC screening mask greater state/regional disparities, not fully explaining the urban-rural mortality gap. Other factors (i.e. access to care, treatment differences) must be considered.