Lower Neighborhood-Level Socioeconomic Status Is Associated with Lower Colorectal Cancer Screening Uptake in the Southern Community Cohort Study.

Abstract

Colorectal cancer is highly preventable with timely screening, but screening modalities are widely underused, especially among those of low individual-level socioeconomic status (SES). In addition to individual-level SES, neighborhood-level SES may also play a role in colorectal cancer screening completion through less geographic access to health care, transportation, and community knowledge of and support for screenings. We investigated the associations of neighborhood SES using a census tract-level measure of social and economic conditions with the uptake of colonoscopy and stool-based testing. We utilized data from the Southern Community Cohort Study, a large, prospective study of English-speaking adults ages 40 to 79 from the southeastern United States with 65% of participants identifying as non-Hispanic Black and 53% having annual household income <$15,000. Neighborhood SES was measured via a neighborhood deprivation index compiled from principal component analysis of 11 census-tract variables in the domains of education, employment, occupation, and poverty; screening was self-reported at the baseline interview (2002-2009) and follow-up interview (2008-2012). We found that participants residing in the lowest SES areas had lower odds of ever undergoing colonoscopy (ORQ5vsQ1 = 0.75; 95% confidence interval, 0.68-0.82) or stool-based colorectal cancer testing (ORQ5vsQ1 = 0.71; 95% confidence interval, 0.63-0.80) while adjusting for individual-level SES factors. Associations were consistent between neighborhood SES and screening in subgroups defined by race, sex, household income, insurance, or education (P > 0.20 for all interaction tests). Our findings suggest that barriers to screening exist at the neighborhood level and that residents of lower SES neighborhoods may experience more barriers to screening using colonoscopy and stool-based modalities. Prevention Relevance: This study presents evidence that persons living in lower SES neighborhoods use colorectal cancer screening modalities at lower rates. Screening is highly preventive of colorectal cancer, but it has limited benefit if it cannot be utilized. Addressing neighborhood-level barriers to screening may improve socioeconomic disparities in colorectal cancer.