Social Determinants of Health and COVID-19 Mortality

The COVID-19 pandemic has disproportionately affected racial and ethnic minorities. While this unfortunately aligns with health inequities that have historically plagued these populations, one study sought to understand how structural factors are correlated with COVID-19 mortality across racial and ethnic groups.

The investigators wrote, “Evidence shows that social determinants of health (SDOH), the structural conditions that characterize where people live, work, and play, are substantial factors in racial and ethnic health disparities, including disparities in COVID-19 infection and mortality rates.”

The cross-sectional study, published yesterday in the Journal of the American Medical Association (JAMA), included 3142 counties from 50 US states and the District of Columbia. The investigators used measures of SDOH in the US counties with the highest proportions of racial and ethnic minority populations and mortalities.

The investigators pulled county-level COVID-19 data reported from the US Centers for Disease Control and Prevention (CDC) from January 22, 2020-February 28, 2021. The data sets included demographic information, such as race and ethnicity, as well as other SDOH measures. The study included the US’s 3 largest racial and ethnic groups, Black/African American, Hispanic/Latinx, and non-Hispanic White.

The study paid special attention to how SDOH vary contextually, such as in urban versus rural areas. The investigators strove to represent the spatial effects of COVID-19, “given that the virus is highly transmissible between individuals (spatial dependence) and has exhibited uneven spread across geographic areas and populations (spatial heterogeneity).”

The investigators used 4 indexes to measure SDOH: socioeconomic advantage index, limited mobility index, urban core opportunity index, and mixed immigrant cohesion and accessibility index. Utilizing spatial regression models, they examined the associations between SDOH and county-level COVID-19 mortalities.

Counties with a high proportion of a single racial and ethnic population and a high rate of COVID-19 mortality were identified as “concentrated longitudinal-impact counties.” Of the 3142 counties included in the study, 531 were considered concentrated longitudinal-impact counties. Among the concentrated longitudinal-impact counties, 11% had a larger Black/African American population relative to other counties, 6.3% had a larger Hispanic/Latinx population, and 1.1% had a larger non-Hispanic White population.

Across rural, suburban, and urban regions, the concentrated longitudinal-impact counties with a proportionally larger Black/African American population experienced higher income inequality and more preventable hospital stays. Most concentrated longitudinal-impact counties with a large Hispanic/Latinx population compared with other counties were in urban areas, and of those counties, the majority had a high percentage of people without health insurance.

Mortality rates in urban areas were most prevalent in immigrant communities with traditional family structures, multiple accessibility stressors, and housing overcrowding. Across all types of communities, areas with limited internet access had higher mortality rates, but this was especially prevalent in urban areas.

The investigators found correlations between SDOH measures and COVID-19 mortality across various racial and ethnic groups and community types. They recommended future research to explore “the different dimensions and regional patterns of SDOH to address health inequity and guide policies and programs.”