Colorectal cancer incidence in Texas border versus non-border counties.

Abstract

21 Background: There are 32 counties and 2.8 million people in the Texas border region. The population is 88.4% Hispanic with estimates that 47% lack health insurance - not including non-US citizens, who are more likely to lack health insurance than US citizens. In 2014, 7 of the 20 US counties with the lowest CRC screening rates were in Texas, 6 of which were Texas border counties. It is unknown how the incidence of CRC in Texas border counties has changed over time compared to non-border counties. In this study, we investigate changes in the incidence of CRC in Texas border counties between 2000 and 2017. Methods: Data were obtained from the Texas Department of State Health Service’s Texas Cancer Registry. Cases of patients aged 18 or older between 2000 and 2017 were included in our analysis. Cases were excluded if they contained incomplete information regarding age, sex, year of diagnosis, site of diagnosis or poverty level. Simple descriptive statistics were calculated for all covariates. Chi-square tests of independence were created to examine the association between each categorical variable and border county status. Age-adjusted incidence rates (AAIR) were created for the state overall and by border status. SAS v9.4 was used for all data analysis. Results: In border counties from 2000 to 2017, the overall AAIR decreased from 65.9 (per 100,000) to 56.7. In those 50-64 years old and 65 years and older residing in border counties, the AAIR increased from 63.3 to 78.1 and decreased from 244 to 176.1, respectively. In non-border counties from 2000 to 2017, the overall AAIR decreased from 85.2 (per 100,000) to 57.3. In those 50-64 years old and 65 years and older residing in non-border counties, the AAIR decreased from 94.9 to 78.0 and from 303 to 168.5, respectively. Conclusions: The overall AAIR of CRC was lower in Texas border counties compared to non-border counties, which is likely a consequence of lower screening rates in border counties. The overall AAIR decreased at a slower rate in Texas border counties compared to non-border counties, which may represent lower rates of utilization of CRC screening over time in border counties. The increase in the AAIR among those 50-64 years old in Texas border counties warrants further investigation.