Distance to endoscopy services amplifies racial inequities in colorectal cancer mortality in Washington state

Background This study evaluates relationships among race, access to endoscopy services, and colorectal cancer (CRC) mortality in Washington state (WA). Methods We overlayed the locations of ambulatory endoscopy services with place of residence at time of death, using Department of Health data (2011–2018). We compared CRC mortality data within and outside a 10 km buffer from services. We used linear regression to assess the impact of distance and race on age at death while adjusting for gender and education level. Results Age at death: median 72.9y vs. 68.2y for white vs. non-white (p < 0.001). The adjusted model showed that non-whites residing outside the buffer died 6.9y younger on average (p < 0.001). Non-whites residing inside the buffer died 5.2y younger on average (p < 0.001), and whites residing outside the buffer died 1.6y younger (p < 0.001). We used heatmaps to geolocate death density. Conclusions Results suggest that geographic access to endoscopy services disproportionately impacts non-whites in Washington. These data help identify communities which may benefit from improved access to alternative colorectal cancer screening methods.