Methodologic Strategies for Quantifying Associations of Historical and Contemporary Mortgage Discrimination on Population Health Equity: A Systematic Review.

BACKGROUND: Mortgage discrimination refers to the systematic withholding of home mortgages from minoritized groups. In recent years, there has been an increase in empirical research investigating associations of historical and contemporary mortgage discrimination on contemporary  outcomes. Investigators have used a variety of measurement methods and approaches, which may have implications for results and interpretation. PURPOSE: We conducted a systematic review of peer-reviewed literature that has quantified links between both historical and current mortgage discrimination with contemporary adverse environmental, social, and health outcomes. Our goals were to document the methodology used to measure and assign mortgage discrimination, to assess implications for results and interpretation, and to make recommendations for future work. METHODS: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, literature searches were conducted in September 2022 using terms that combined concepts of mortgage discrimination, health, and neighborhood environment. RESULTS: In total, 45 papers fit the eligibility criteria. In these, researchers investigated associations between mortgage discrimination and: (1) health outcomes (N = 28); (2) environmental and social exposures including heat, air pollution, greenspace, soil lead levels, and crime (N = 12); and (3) built environment features, including presence of retail alcohol, fast food, and tobacco stores (N = 5). Eleven included studies used Home Mortgage Discrimination Act (HMDA) data to identify racialized bias in mortgage discrimination or redlining, and 34 used Homeowner Loan Corporation (HOLC) maps. The construction and parametrization of mortgage discrimination or redlining and the spatial assignment of HOLC grades to contemporary addresses or neighborhoods varied substantially across studies. CONCLUSIONS: Results from our review suggest the need for careful consideration of optimal methods to analyze mortgage discrimination such as HOLC spatial assignment or HMDA index parametrization, contemplation of covariates, and place-based knowledge of the study location.

Associations between 1930s HOLC grades and estimated population burden of cardiovascular disease risk factors in 2020.

Studies have recently begun to explore the potential long-term health impacts of homeownership policies implemented in the New Deal era. We investigated the association between assigned grades of lending risk by the Home Owners' Load Corporation (HOLC) maps from the 1930s and present-day prevalence of three cardiovascular risk factors (diabetes and obesity in 2020, and hypertension in 2019), estimated at the census tract level in the United States. To minimize potential confounding, we adjusted for sociodemographic data from the time period when HOLC maps were made. We calculated propensity scores (predicted probability of receiving a HOLC grade) and created a pseudo-population using inverse probability weighting. We then employed marginal structural models to estimate prevalence differences comparing A vs. B, B vs. C, and C vs. D HOLC grades. Adjusting only for regions, a less desirable HOLC grade was associated with higher estimated prevalence rates of present-day cardiovascular risk factors; however, most differences were no longer significant after applying propensity score methods. The one exception was that the prevalence of diabetes, hypertension, and obesity were all higher in C vs. B graded census tracts, while no differences were observed for C and D and A and B comparisons. These results contribute to a small body of evidence that suggests historical "yellowlining" (as C grade was in color yellow) may have had persistent impacts on neighborhood-level cardiovascular risk factors 80 years later.

Historic Residential Redlining and Present-Day Social Determinants of Health, Home Evictions, and Food Insecurity within US Neighborhoods.

OBJECTIVE: Examine the association between historic residential redlining and present-day racial/ethnic composition of neighborhoods, racial/ethnic differences in social determinant of health domains, and risk of home evictions and food insecurity. RESEARCH DESIGN AND METHODS: We examined data on 12,334 (for eviction sample), and 8996 (for food insecurity sample), census tracts in 213 counties across 37 states in the USA with data on exposure to historic redlining. First, we examined relationships between Home Owners' Loan Corporation (HOLC) redlining grades (A="Best", B="Still Desirable", C="Definitely Declining", D="Hazardous") and present-day racial/ethnic composition and racial/ethnic differences in social determinant of health domains of neighborhoods. Second, we examined whether historic redlining is associated with present-day home eviction rates (measured across eviction filings rates, and eviction judgment rates for 12,334 census tracts in 2018) and food insecurity (measured across low supermarket access, low supermarket access and income, low supermarket access and low car ownership for 8996 census tracts in 2019). Multivariable regression models were adjusted for census tract population, urban/rural designation, and county level fixed effects. RESULTS: Relative to areas with a historic HOLC grading of "A (Best)", areas with a "D (Hazardous)" grading had a 2.59 (95%CI=1.99-3.19; p-value<0.01) higher rate of eviction filings, and a 1.03 (95%CI=0.80-1.27; p-value<0.01) higher rate of eviction judgments. Compared to areas with a historic HOLC grading of "A (Best)", areas rated with a "D (Hazardous)" had a 16.20 (95%CI=15.02-17.79; p-value<0.01) higher rate of food insecurity based on supermarket access and income, and a 6.15 (95%CI =5.53-6.76; p-value<0.01) higher rate of food insecurity based on supermarket access and car ownership. CONCLUSIONS: Historic residential redlining is significantly associated with present-day home evictions and food insecurity, highlighting persistent associations between structural racism and present-day social determinants of health.

Redlining, racism and food access in US urban cores.

In the 1930s, the Home Owners' Loan Corporation (HOLC) graded the mortgage security of urban US neighborhoods. In doing so, the HOLC engaged in the practice, imbued with racism and xenophobia, of "redlining" neighborhoods deemed "hazardous" for lenders. Redlining has caused persistent social, political and economic problems for communities of color. Linkages between redlining and contemporary food access remain unexamined, even though food access is essential to well-being. To investigate this, we used a census tract-level measure of low-income and low grocery store food access from the US Department of Agriculture Food Access Research Atlas, redlining data from Mapping Inequality Project, and demographic data from the American Community Survey. We employed generalized estimating equations with robust covariance estimates to analyze data pertaining to 10,459 census tracts in 202 US cities. Tracts that the HOLC graded as "C" ("decline in desirability") and "D" ("hazardous") had reduced contemporary food access compared to those graded "A" ("best"). Increases in contemporary census tract proportions of Black, Hispanic, or other racial/ethnic minority residents, as well as disabled residents, were associated with reduced food access. Increases in contemporary proportions of residents age 75 years and older or those without a car were associated with better food access. Tracts that underwent housing redevelopment since being graded had better food access, while those undergoing gentrification had reduced food access. Results suggest that issues of redlining, housing discrimination, racism, ableism, displacement, and food inaccessibility are deeply intertwined.

Historic racism in Kansas City affects Today's pediatric asthma burden.

Asthma morbidity is unequally distributed across populations throughout the United States, and reasons remain unclear. To assess how historical structural racism correlates with current day asthma disparities, we conducted a retrospective cohort study of 10,736 pediatric patients, ages 3-19 years, with two or more asthma encounters between October 2017-October 2019. Patient addresses were matched with historic Home Owners' Loan Corporation (HOLC) maps - which provide a measure of historic structural racism. Residential proximity to pollution sources served as an additional exposure measure. Healthcare utilization and asthma severity were studied against age, race, SES, geographic proximity to pollution, and HOLC grades. Patients living in historically divested neighborhoods and BIPOC patients were likely to require more acute care for asthma, even when adjusting for present day SES and residential proximity to pollution sources. This supports the assertion that historic structural racism influences present-day health.

The Relationship of Historical Redlining with Present-Day Neighborhood Environmental and Health Outcomes: A Scoping Review and Conceptual Model.

Following the Great Depression and related home foreclosures, the federal government established new agencies to facilitate access to affordable home mortgages, including the Home Owners' Loan Corporation (HOLC) and Federal Housing Administration (FHA). HOLC and FHA directed widespread neighborhood appraisals to determine investment risk, referred to as "redlining," which took into account residents' race. Redlining thereby contributed to segregation, disinvestment, and racial inequities in opportunities for homeownership and wealth accumulation. Recent research examines associations between historical redlining and subsequent environmental determinants of health and health-related outcomes. In this scoping review, we assess the extent of the current body of evidence, the range of outcomes studied, and key study characteristics, examining the direction and strength of the relationship between redlining, neighborhood environments, and health as well as different methodological approaches. Overall, studies nearly universally report evidence of an association between redlining and health-relevant outcomes, although heterogeneity in study design precludes direct comparison of results. We critically consider evidence regarding HOLC's causality and offer a conceptual framework for the relationship between redlining and present-day health. Finally, we point to key directions for future research to improve and broaden understanding of redlining's enduring impact and translate findings into public health and planning practice.

Changes in Concentration of Extracellular Aspartate and Glutamate During Cortical Spreading Depression in the Rat Cerebral Cortex

The author has examined the effect of cortical spreading depression(CSD) on the changes in extracellular concetration of aspartate and glutamate in the neocortex of anesthetized rats using microdialysis and high performance liquid chromatography(HPLC). The rats were prepared by halothane anesthesia and artificial ventilation. Rats were placed in a stereotaxic frame, and craniotomies were performed over the frontal and parietal cortexes on one side. The CSD was elicited by local application of KCI-soaked small pellets to the frontal cortex. The CSD was monitored by the changes of direct current(DC) potential in the parietal cortex. The microdialysis probe was implanted in the anterior part of the parietal cortex. Amino acids were analyzed by HPLC and fluorescence detection. Baseline concentration of the aspartate was 34.9+/-15.9nM and that of glutamate was 189.8+/-29.1nM(mean standard deviation). The perfusate for analysis was obtained 30 minutes after the beginning of the 300mM KCl induced CSD. Aspartate was found to increase to 146+/-55% baseline, glutamate up to 173+/-30% baseline(mean standard deviation). The increment of glutamate was statistically significant(p<0.05). Then 2M KCI-doaked pellets were applied for more frequent CSD amd the samples were collected. Aspartate increased up to 258+/-97% baseline, glutamate up to 174+/-57% baseline(mean standard deviation), The increment of glutamate and aspartate accompanying 2M KCI induced CSD were also statistically significant(p<0.05). These data suggest that the excitatory amino acids were released during the CSD and this may explain the various aspects of CSD that could contribute to the secondary neuronal damage in the compromised nerve cell.