The effect of historic redlining on firearm violence.

BACKGROUND: Firearm homicides disproportionately affect young Black men, which in turn have lasting impact of communities of color as a whole. Previous cross-sectional studies have highlighted the role of discriminatory housing policies on the incidence of urban firearm violence. We sought to estimate the effects of racist housing policies on firearm incidence. METHODS: Firearm incident data were obtained from the Boston Police Department and point locations spatially joined with vector files outlining the original 1930 Home Owner Loan Corporation (HOLC) Redlining maps. A regression discontinuity design was used to assess the increased rate of firearm violence crossing from historically "desirable" neighborhoods (Green) to historically "hazardous" neighborhoods (Red and Yellow) based on HOLC definitions. Linear regression models were fit on either side of the geographic boundaries with firearm incidents graphed at varying distances and the regression coefficient calculated at the boundary. RESULTS: Crossing from desirable to Red hazardous designation there was a significant discontinuity with an increase of 4.1 firearm incidents per 1,000 people (95% CI 0.68,7.55). Similarly, when crossing from desirable areas to the Yellow hazardous designation there was a significant discontinuity and increase of 5.9 firearm incidents per 1,000 people (95% CI 1.85,9.86). There was no significant discontinuity between the two hazardous HOLC designations (coefficient -0.93, 95% CI -5.71, 3.85). CONCLUSIONS: There is a significant increase in firearm incidents in historically redlined areas of Boston. This suggests that interventions should focus on downstream socioeconomic, demographic, and neighborhood detriments of historically discriminatory housing policies in order to address firearm homicides.

The effect of medicare and screening guidelines on colorectal cancer outcomes.

BACKGROUND: Colorectal cancer screening has been shown effective at reducing stage at presentation, but there is differential uptake of screening based on insurance status. We sought to determine the population-level effect of Medicare and screening guidelines on colorectal screening by race and region. METHODS: Data on Black and white patients with colorectal cancer were obtained from the SEER database. Regression discontinuity was used to assess the causal effect of near-universal health insurance (represented by age 65) and United States Preventive Services Task Force guidelines (age 50) on the proportion of people presenting at advanced stage. This was stratified by race and region. RESULTS: In the Southern United States, Black patients saw a significant decrease in advanced stage at presentation at age 65 (coefficient -0.12, p = 0.003), while white patients did not (coefficient -0.03, p = 0.09). At age 50, neither Black (coefficient 0.09, p = 0.10) nor white patients (coefficient -0.04, p = 0.1) saw a significant decrease in advanced stage. In the Western U.S., neither Black (coefficient 0.02, p = 0.72) or white patients (coefficient -0.02, p = 0.09) saw a significant decrease in advanced stage at age 65; however, both Black (coefficient -0.20, p = 0.008) and white patients (coefficient -0.05, p = 0.03) saw a significant decrease at age 50. CONCLUSIONS: Our data highlight the significant impact that near-universal insurance has on reducing colorectal cancer stage at presentation in areas with poor baseline insurance coverage, particularly for Black patients. To reduce disparities in advanced stage at presentation for colorectal cancer, state-level insurance coverage should be addressed.

Socioeconomic Mediation of Racial Segregation in Pancreatic Cancer Treatment and Outcome Disparities.

OBJECTIVE: To understand the mediating effect of socioeconomic factors on the association between residential segregation and racial disparities in pancreatic cancer (PC). BACKGROUND: Black patients with PC present at a later stage and have worse mortality than White patients. These disparities have been explained by the level of residential segregation. METHODS: Data were obtained from Surveillance, Epidemiology, and End-Results (SEER) and included all Black and White patients who were diagnosed with PC between 2005 and 2015. The primary exposure variable was the Index of Dissimilarity, a validated measure of segregation. County-level socioeconomic variables from the US Census were assessed as mediators. The primary outcomes were advanced stage at diagnosis, surgical resection for localized disease, and overall mortality. Generalized structural equation modeling was used to assess the mediation of each of the socioeconomic variables. RESULTS: Black patients in the highest levels of segregation saw a 12% increased risk [relative risk=1.12; 95% confidence interval (CI): 1.08, 1.15] of presenting at an advanced stage, 11% decreased likelihood of undergoing surgery (relative risk=0.89; 95% CI: 0.83, 0.94), and 8% increased hazards of death (hazard ratio=1.08; 95% CI: 1.03, 1.14) compared with White patients in the lowest levels. The Black share of the population, insurance status, and income inequality mediated 58% of the total effect on the advanced stage. Poverty and Black income immobility mediated 51% of the total effect on surgical resection. Poverty and Black income immobility mediated 50% of the total effect on overall survival. CONCLUSIONS: These socioeconomic factors serve as intervention points for legislators to address the social determinants inherent to the structural racism that mediate poor outcomes for Black patients.

Historic redlining, social mobility, and firearm violence.

BACKGROUND: Much of the recorded medical literature focuses on individual-level factors that contribute to firearm violence. Recently, studies have highlighted higher incidence of firearm violence in historically redlined and marginalized areas, but few have gone on to study the downstream associations causing these differences. This study aims to understand the effects of historic redlining and current income mobility on firearm violence. METHODS: Using a retrospective cross-sectional design, shooting incidents were spatially joined with redlining vector files and linked to income mobility data (how much a child makes in adulthood). Participants included all assault and homicide incidents involving a firearm in the city of Boston, between 2016 and 2019. The exposure of interest was redlining designation as outlined by the Home Owner's Loan Corporation (HOLC) in the 1930s and income mobility, stratified by race, defined as the income of a child in their 30s compared with where they grew up (census tract level). The outcome measured was shooting rate per census block. RESULTS: We find that increases in Black income mobility (BIM) and White income mobility (WIM) are associated with significant decreases in rates of firearm incidents in all HOLC designations; however, there is a larger decrease with increasing BIM (relative risk, 0.47 per unit increase in BIM [95% confidence interval, 0.35-0.64]; relative risk, 0.81 per unit increase in WIM [95% confidence interval, 0.71-0.93]). Plotting predicted rates of firearm violence in each HOLC designation at different levels of BIM, there were no significant differences in shooting rates between historically harmful and beneficial classifications above $50,000 of BIM. Despite level of WIM, there were continued disparities between harmful and beneficial HOLC classification. CONCLUSION: These findings highlight the importance of structural racism in the form of redlining and discriminatory housing policies, and the preclusion from economic mobility therein, on the incidence of firearm violence today. LEVEL OF EVIDENCE: Prognostic and Epidemiological; Level IV.

The Impact of Residential Racial Segregation on Non-Small Cell Lung Cancer Treatment and Outcomes.

BACKGROUND: Despite decreases in lung cancer incidence, racial disparities in diagnosis and treatment persist. Residential segregation and structural racism have effects on socioeconomic status for black people, affecting health care access. This study aims to determine the impact of residential segregation on racial disparities in non-small cell lung cancer (NSCLC) treatment and mortality. METHODS: Patient data were obtained from Surveillance, Epidemiology, and End Results Program database for black and white patients diagnosed with NSCLC from 2004-2016 in the 100 most populous counties. Regression models were built to assess outcomes of interest: stage at diagnosis and surgical resection of disease. Predicted margins assessed impact of index of dissimilarity (IoD) on these disparities. Competing risk regressions for black and white patients in highest and lowest quartiles of IoD were used to assess cancer-specific mortality. RESULTS: Our cohort had 193,369 white and 35,649 black patients. Black patients were more likely to be diagnosed at advanced stage than white patients, with increasing IoD. With increasing IoD, black patients were less likely to undergo surgical resection than white patients. Disparities were eliminated at low IoD. Black patients at high IoD had lower cancer-specific survival. CONCLUSIONS: Black patients were more likely to present at advanced disease, were less likely to receive surgery for early stage disease, and had higher cancer-specific mortality at higher IoD. Our findings highlight the impact of structural racism and residential segregation on NSCLC outcomes. Solutions to these disparities must come from policy reforms to reverse residential segregation and deleterious socioeconomic effects of discriminatory policies.

Redlining, structural racism, and lung cancer screening disparities.

OBJECTIVE: The objective of this study was to understand the effect of historical redlining (preclusion from home loans and wealth-building for Black Americans) and its downstream factors on the completion of lung cancer screening in Boston. METHODS: Patients within our institution were identified as eligible for lung cancer screening on the basis of the United State Preventive Service Task Force criteria and patient charts were reviewed to determine if patients completed low-dose computed tomography screening. Individual addresses were geocoded and overlayed with original 1930 Home Owner Loan Corporation redlining vector files. Structural equation models were used to estimate the odds of screening for Black and White patients, interacted with sex, in redlined and nonredlined areas. RESULTS: Black patients had a 44% lower odds of screening compared with White (odds ratio [OR], 0.66; 95% CI, 0.52-0.85). With race as a mediator, Black patients in redlined areas were 61% less likely to undergo screening than White patients (OR, 0.39; 95% CI, 0.24-0.64). Similarly, in redlined areas Black women had 61% (OR, 0.39; 95% CI, 0.21-0.73) and Black men 47% (OR, 0.53; 95% CI, 0.29-0.98) lower odds of screening compared with White men in redlined areas. CONCLUSIONS: Despite higher rates of lung cancer screening in redlined areas, Black race mediated worse screening rates in these areas, suggesting racist structural factors contributing to the disparities in lung cancer screening completion among Black and White patients. Furthermore, these disparities were more apparent in Black women, suggesting that racial and gender intersectional discrimination are important in lung cancer screening completion.

The Impact of Income and Social Mobility on Colorectal Cancer Outcomes and Treatment: A Cross-sectional Study.

OBJECTIVE: To determine the impact of income mobility on racial disparities in colorectal cancer. BACKGROUND: There are well-documented disparities in colorectal cancer treatment and outcomes between Black and White patients. Socioeconomic status, insurance, and other patient-level factors have been shown important, but little has been done to show the discriminatory factors that lead to these outcomes. METHODS: Data were obtained from the Surveillance Epidemiology and End-Results database for Black and White patients with colorectal cancer between 2005 and 2015. County level measures of Black (BIM) and White income mobility (WIM) were obtained from the Opportunity Atlas as a measure of intergenerational poverty and social mobility. Regression models were created to assess the relative risk of advanced stage at diagnosis (Stage IV), surgery for localized disease (Stage I/II), and cancer-specific mortality. RESULTS: There was no significant association of BIM or WIM on advanced stage at diagnosis in Black or White patients. An increase of $10,000 of BIM was associated with a 9% decrease in hazards of death for both Black (hazard ratio 0.91, 95% confidence interval 0.86,0.95) and White (0.91, 95%CI 0.90,0.93) patients, while the same increase in WIM was associated with no significant difference in hazards among Black patients (hazard ratio 0.99, 95% confidence interval 0.97,1.02). There were no predicted racial differences in hazards of death at high levels of BIM. CONCLUSIONS: Increased Black income mobility significantly improves survival for both Black and White patients. Interventions aimed at increasing economic and social mobility could significantly decrease mortality in both Black and White patients while alleviating disparities in outcomes.

The role of racial segregation in treatment and outcomes among patients with hepatocellular carcinoma.

BACKGROUND: There is a long history of segregation in the U.S.A with enduring impacts on cancer outcomes today. We evaluated the impact of segregation on racial disparities in Hepatocellular Carcinoma (HCC) treatment and outcomes. METHODS: We obtained data on black and white patients with HCC from the SEER program (2005-2015) within the 100 most populous participating counties. Our exposure was the index of dissimilarity (IoD), a validated measure of segregation. Outcomes were overall survival, advanced stage at diagnosis (Stage III/IV) and surgery for localized disease (Stage I/II). Cancer-specific survival was assessed using Kaplan-Meier estimates. RESULTS: Black patients had a 1.18 times increased risk (95%CI 1.14,1.22) of presenting at advanced stage as compared to white patients and these disparities disappeared at low levels of segregation. In the highest quartile of IoD, black patients had a significantly lower survival than white (17 months vs 27 months, p < 0.001), and this difference disappeared at the lowest quartile of IoD. CONCLUSIONS: Our data illustrate that structural racism in the form racial segregation has a significant impact on racial disparities in the treatment of HCC. Urban and health policy changes can potentially reduce disparities in HCC outcomes.

Residential Racial Segregation and Disparities in Breast Cancer Presentation, Treatment, and Survival.

OBJECTIVE: To understand the role of racial residential segregation on Black-White disparities in breast cancer presentation, treatment, and outcomes. SUMMARY OF BACKGROUND DATA: Racial disparities in breast cancer treatment and outcomes are well documented. Black individuals present at advanced stage, are less likely to receive appropriate surgical and adjuvant treatment, and have lower overall and stage-specific survival relative to White individuals. METHODS: Using data from the Surveillance, Epidemiology, and End Results program, we performed a retrospective cohort study of Black and White patients diagnosed with invasive breast cancer from 2005 to 2015 within the 100 most populous participating counties. The racial index of dissimilarity was used as a validated measure of residential segregation. Multivariable regression was performed, predicting advanced stage at diagnosis (stage III/IV), surgery for localized disease (stage I/II), and overall stage-specific survival. RESULTS: After adjusting for age at diagnosis, estrogen/progesterone receptor status, and region, Black patients have a 49% greater risk (relative risk [RR] 1.49 95% confidence interval [CI] 1.27, 1.74) of presenting at advanced stage with increasing segregation, while there was no observed difference in Whites (RR 1.04, 95% CI 0.93, 1.16). Black patients were 3% less likely to undergo surgical resection for localized disease (RR 0.97, 95% CI 0.95, 0.99) with increasing segregation, while Whites saw no significant difference. Black patients had a 29% increased hazard of death (RR 1.29, 95% CI 1.04, 1.60) with increasing segregation; there was no significant difference among White patients. CONCLUSIONS: Our data suggest that residential racial segregation has a significant association with Black-White racial disparities in breast cancer. These findings illustrate the importance of addressing structural racism and residential segregation in efforts to reduce Black-White breast cancer disparities.

The impact of racial residential segregation on prostate cancer diagnosis and treatment.

OBJECTIVES: To examine the effects of racial residential segregation and structural racism on the diagnosis, treatment, and outcomes of patients with prostate cancer. PATIENTS AND METHODS: This retrospective cohort study examined men diagnosed with prostate cancer between 2005 and 2015. We collected data from Black and White men, aged ≥30 years, living within the 100 most populous counties participating in the Surveillance, Epidemiology, and End Results programme, a nationally representative dataset. The racial Index of Dissimilarity, a validated measure of segregation, was the primary exposure of interest. Outcomes of interest included advanced stage at diagnosis (Stage IV), surgery for localised disease (Stage I-II), and 10-year overall and cancer-specific survival. Multivariable Poisson regression analyses with robust error variance estimated the relative risk (RR) of advanced stage at diagnosis and surgery for localised disease at differing levels of segregation. Survival analysis was performed using competing hazards analysis. RESULTS: Multivariable models estimating stage at diagnosis showed that the disparities between Black and White men disappeared at low levels of segregation. Disparities in receiving surgery for localised disease persisted across all levels of segregation. In racially stratified analyses, segregation had no effect on stage at diagnosis or surgical resection for Black patients. White patients saw a 56% (RR 0.42, P < 0.001) reduced risk of presenting at advanced stage and 20% increased likelihood (RR 1.20, P < 0.001) of surgery for localised disease. Black patients in the lowest segregation areas had the lowest overall mortality, but the highest cancer-specific mortality. CONCLUSIONS: Our study provides evidence that residential segregation has a significant impact on Black-White disparities in prostate cancer, likely through improved outcomes for White patients and worse outcomes for Black patients in more segregated areas. These findings suggest that mitigating segregation and the downstream effects of socioeconomic factors could alleviate these disparities.