Population-Level Disparities in COVID-19: Measuring the Independent Association of the Proportion of Black Population on COVID-19 Cases and Deaths in US Counties

Abstract

Context: There is a need to understand population race and ethnicity disparities in the context of sociodemographic risk factors in the US experience of the COVID-19 pandemic. Objective: Determine the association between county-level proportion of non-Hispanic Black (NHB) on county COVID-19 case and death rates and observe how this association was influenced by county sociodemographic and health care infrastructure characteristics. Design and Setting: This was an ecologic analysis of US counties as of September 20, 2020, that employed stepwise construction of linear and negative binomial regression models. The primary independent variable was the proportion of NHB population in the county. Covariates included county demographic composition, proportion uninsured, proportion living in crowded households, proportion living in poverty, population density, state testing rate, Primary Care Health Professional Shortage Area status, and hospital beds per 1000 population. Main Outcome Measures: Outcomes were exponentiated COVID-19 cases per 100 000 population and COVID-19 deaths per 100 000 population. We produced county-level maps of the measures of interest. Results: In total, 3044 of 3142 US counties were included. Bivariate relationships between the proportion of NHB in a county and county COVID-19 case (Exp β = 1.026; 95% confidence interval [CI], 1.024-1.028; P < .001) and death rates (rate ratio [RR] = 1.032; 95% CI, 1.029-1.035; P < .001) were not attenuated in fully adjusted models. The adjusted association between the proportion of NHB population in a county and county COVID-19 case was Exp β = 1.025 (95% CI, 1.023-1.027; P < .001) and the association with county death rates was RR = 1.034 (95% CI, 1.031-1.038; P < .001). Conclusions : The proportion of NHB people in a county was positively associated with county COVID-19 case and death rates and did not change in models that accounted for other socioecologic and health care infrastructure characteristics that have been hypothesized to account for the disproportionate impact of COVID-19 on racial and ethnic minority populations. Results can inform efforts to mitigate the impact of structural racism of COVID-19.

Place, Race, and Case: Examining Racialized Economic Segregation and COVID-19 in Louisiana

“…This relationship varied across the state. These state-level findings are consistent with recent research, including one national study that found significant association between residential segregation and COVID-19 outcomes [24], and other national studies focusing on concentration (rather than segregation) of Black and Hispanic residents and income inequality [35,70,104]. However, one longitudinal study found the relationship between income inequality and COVID-19 cases weakened over time, suggesting inequality may be strongest before the virus becomes pervasive [104].…”

National Population-Level Disparities in COVID-19 Mortality Across the Intersection of Race/Ethnicity and Sex in the United States

“…Our general estimation strategy is to calculate upper and lower bounds for the mortality rates of interest, which subsequently determine the upper and lower bounds for the associated mortality RR’s and RD’s. The upper bounds for the age-specific and age-adjusted mortality rates are obtained by (i) appropriately combining COVID-19 death counts with unknown race/ethnicity and COVID-19 death counts for the racial/ethnic group of interest, and (ii) assuming the maximal number (9) of deaths corresponding to suppressed death counts for the racial/ethnic group of interest or those with unknown race/ethnicity. The lower bounds for the age-specific and age-adjusted mortality rates are obtained by (i) assuming COVID-19 death counts with unknown race/ethnicity all do not correspond to the racial/ethnic group of interest, and (ii) assuming the minimal number (1) of deaths corresponding to suppressed death counts for the racial/ethnic group of interest.…”

“…We focus the attention of this paper on quantifying disparities in population-level COVID-19 mortality. Substantial scientific research has uncovered disparities in COVID-19 mortality outcomes in the U.S. by race/ethnicity (e.g., (3, 4, 5, 6, 7, 8, 9, 10, 11)), as well as between males and females (e.g., (12, 13, 14, 15, 16, 17, 18, 19)). However, research on U.S. population-level disparities in COVID-19 mortality outcomes across the intersection of race/ethnicity and sex has been limited, largely due to the absence of requisite publicly available data, which represents a critical research gap in the quantification and understanding of the nature of population-level disparities in COVID-19 mortality outcomes between subgroups.…”

Actual Racial/Ethnic Disparities in COVID-19 Mortality for the Non-Hispanic Black Compared to Non-Hispanic White Population in 353 US Counties and Their Association with Structural Racism

“…In an attempt to characterize racial disparities in COVID-19 cases or deaths in counties, numerous previous studies have reported that the proportion of Black residents in a county is positively associated with the overall COVID-19 death rate in that county [ 4 – 22 ]. Our concern was that the proportion of Black residents may be correlated with factors that increase not only the Black COVID-19 death rate, but the White COVID-19 death rate as well.…”

“…The overwhelming majority of studies that have explored racial disparities in COVID-19 mortality at the county level have done so by examining the relationship between the percentage of Black or Latinx residents in a county and that county’s overall COVID-19 death rate [ 4 – 22 ]. However, finding such a relationship does not necessarily demonstrate that a racial disparity exists.…”