Association between racial residential segregation and screening uptake for colorectal and cervical cancer among Black and White patients in five US health care systems

Background: Despite increased recognition that structural racism contributes to poorer health outcomes for racial and ethnic minorities, there are knowledge gaps about how current patterns of racial residential segregation are associated with cancer screening uptake. The authors examined associations between Black residential segregation and screening for colorectal cancer (CRC) and cervical cancer among non-Hispanic Black and non-Hispanic White adults. Methods: This was a retrospective study of CRC and cervical cancer screening-eligible adults from five health care systems within the Population-Based Research to Optimize the Screening Process (PROSPR II) Consortium (cohort entry, 2010-2012). Residential segregation was measured using site-specific quartiles of the Black local isolation score (LIS). The outcome was receipt of CRC or cervical cancer screening within 3 years of cohort entry (2010-2015). Logistic regression was used to calculate associations between the LIS and screening completion, adjusting for patient-level covariates. Results: Among CRC (n = 642,661) and cervical cancer (n = 163,340) screening-eligible patients, 456,526 (71.0%) and 106,124 (65.0%), respectively, received screening. Across PROSPR sites, living in neighborhoods with higher LIS tended to be associated with lower odds of CRC screening (Kaiser Permanente Northern California: adjusted odds ratio [aOR] LIS trend in Black patients, 0.95 [p < .001]; aOR LIS trend in White patients, 0.98 [p < .001]; Kaiser Permanente Southern California: aOR LIS trend in Black patients, 0.98 [p = .026]; aOR LIS trend in White patients, 1.01 [p = .023]; Kaiser Permanente Washington: aOR LIS trend in White patients, 0.97 [p = .002]. However, for cervical cancer screening, associations with the LIS varied by site and race (Kaiser Permanente Washington: aOR LIS trend in White patients, 0.95 [p < .001]; Mass General Brigham: aOR LIS trend in Black patients, 1.12 [p < .001]; aOR LIS trend in White patients, 1.03 [p < .001]). Conclusions: Across five diverse health care systems, the direction of the association between Black residential segregation and screening varied by PROSPR site, race, and screening type. Additional research, including studies that examine multiple dimensions of segregation and structural racism using intersectional approaches, are needed to further disentangle these relationships.