Abstract A012: The effect of neighborhood deprivation on colorectal cancer patients in Louisiana: A multilevel study
Authors: Li Tingting , Rung Ariane L. , KC Madhav , Hsieh Mei-Chin , Rozek Laura S. , Peters Edward S. 
Published: January 2023

Abstract
Background Colorectal cancer incidence in Louisiana and the US exhibit profound racial and ethnic disparities, determined not only by individual-level predictors but also by neighborhood-level characteristics. Aggregate-level factors such as neighborhood deprivation level, rural/urban status, and accessibility to healthcare facilities are associated with geographic health disparities. This study examines the effect of area neighborhood deprivation on overall and early-onset (age &lt; 50 years) CRC cancer incidence, stage at diagnosis, and survival. Methods From the Louisiana Tumor Registry we identified 18,903 eligible CRC cancer patients using ICD-O-3 codes C180-C189, C199, C209-C212, C218, and C260, with American Joint Committee on Cancer (AJCC) stage 0-IV between 2009 and 2018. The census tract (CT) level Area Deprivation Index (ADI) was calculated for the years 2010-2014 for all CTs where eligible patients reside. We convert the ADI to quantiles such that higher quantiles indicated more disadvantaged neighborhoods. Trend analysis of CRC cancer incidence by CT-level deprivation was conducted. Multilevel models were constructed to evaluate the influence of neighborhood deprivation on risk of advanced stage cancer diagnosis and death. Variables including sex, race/ethnicity, insurance, marital, smoking status, and primary subsite at the individual level and rural/urban status at the neighborhood level were adjusted. Results We observed a positive relationship between neighborhood deprivation and CRC cancer incidence, with an incidence rate of 38.91 (95% CI 37.32-40.50) cases per 100,000 for the least deprived areas and 57.29 (95% CI 55.20-59.37) cases per 100,000 among the CTs with the highest deprivation (P &lt;.0001). For both males and females, CRC incidence increased linearly with higher deprivation, but males experienced stronger association than females. The incidence of early-onset CRC cancer ranged from 7.62 (95% CI 6.82-8.43) cases per 100,000 population in the least deprived quantile to 11.14 (95% CI 9.99-12.29) cases per 100,000 population in the most deprived ADI quantile (P &lt; .0001). Multilevel model results estimate that the probability of advanced stage (AJCC stage II-IV) CRC cancer diagnosis increases as the deprivation index increases. Compared with patients in the least deprived group, living in the most deprived group was associated with the highest risk (OR: 1.31, 95% CI 1.14-1.52). Although the adjusted survival is similar across deprivation quantiles (HR = 1), an advanced stage of diagnosis significantly increases the overall and cause-specific risk of death. Conclusion Overall and early-onset CRC cancer incidence increases in areas with higher neighborhood deprivation level. Greater neighborhood derivation is associated with more advanced stage (AJCC II-IV) CRC cancer diagnosis. Acknowledgment Supported by NIH/NCI 1R01CA259420.
Citation Format: Tingting Li, Ariane L. Rung, Madhav KC, Mei-Chin Hsieh, Laura S. Rozek, Edward S. Peters. The effect of neighborhood deprivation on colorectal cancer patients in Louisiana: A multilevel study [abstract]. In: Proceedings of the 15th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2022 Sep 16-19; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr A012.