Social determinants of health impact Covid-19 survival at the county level

Racial disparities in Covid-19 mortality have nothing to do with biology and everything to do with social inequities, researchers reported in the Journal of Racial and Ethnic Health Disparities.

As with past pandemics in the U.S., reports have noted major disparities in Covid-19 mortality among marginalized populations, with Black people taking the hardest hit. And, according to Michelle DallaPiazza, MD, of the Division of Infectious Diseases in the Department of Medicine at Rutgers New Jersey Medical School in Newark, New Jersey, and colleagues, studies suggest that, rather than hinging on clinical factors, “racial disparities may reflect discrimination propagated by mutually reinforcing, inequitable systems–referred to as structural racism–which could ultimately influence the way in which minorities experience Covid-19 and other illnesses.”

For their analysis, DallaPiazza and colleagues assessed publicly available databases on Covid-19 death rates through Oct. 28, 2020, clinical covariates, and social determinants of health at the country level across the U.S. — SDHs included densely populated housing, a greater burden of chronic disease, limited healthcare access, higher poverty rates, and a higher likelihood of employment as an essential worker.

“Counties with higher death rates had a higher proportion of Black residents and greater levels of adverse social determinants of health,” they wrote. “A one percentage point increase in percent Black residents, percent uninsured adults, percent low birth weight, percent adults without high school diploma, incarceration rate, and percent households without internet in a county increased Covid-19 death rates by 0.9% (95% CI 0.5%–1.3%), 1.9% (95% CI 1.1%–2.7%), 7.6% (95% CI 4.4%–11.0%), 3.5% (95% CI 2.5%–4.5%), 5.4% (95% CI 1.3%–9.7%), and 3.4% (95% CI 2.5%–4.2%), respectively. Counties in the lowest quintile of a measure of economic privilege had an increased Covid-19 death rate of 67.5% (95% CI 35.9%–106.6%). Multivariate regression and subgroup analyses suggested that adverse social determinants of health may partially explain racial disparities in Covid-19 mortality.”

Notably, DallaPiazza and colleagues found that the percentage Black residents in a county is only a predictor of Covid-19 mortality in counties with higher degrees of adverse social determinants of health, “thus suggesting that social constructs and policies mediate the disparate Covid-19 outcomes in Black Americans. This precludes genetic differences as a possible explanation for Covid-19 racial disparities and challenges the harmful belief that racial disparities in illness primarily have a biological basis. Overall, this study provides both qualitative and quantitative evidence that [social determinants of health] play a significant role in influencing increased Covid-19 mortality for Black Americans.”

These results suggest that racial disparities in Covid outcomes stem from multiple compounding sources, but not from biological differences, DallaPiazza and colleagues argued. By identifying areas with a high number of adverse social determinants of health and working to reduce these inequities, health policymakers may be able to identify areas at high risk for Covid mortality and address these disparities.

“Multiple prior studies have linked [social determinants of health] to structural racism, which is deeply ingrained in the U.S. legal and economic systems, shaped by historical injustices, and perpetuated by bias,” they wrote. “As a next step, further research is needed to evaluate the effect of validated markers of structural racism on Covid-19 mortality, and to explore these associations over time as the pandemic evolves. Additional studies related to bias experienced within the healthcare system related to testing, triage, and treatment may also shed additional insights on Covid-19 racial disparities.”

The study authors cited a lack of more local-level data, limitations in Covid-19 mortality data, the use of publicly available data acquired at different time periods, potential confounding variables, and other variables in social determinants of health that were not assessed in their analysis as potential limitations to this study.

John McKenna, Associate Editor, BreakingMED™

Cat ID: 190

Topic ID: 79,190,730,933,190,926,192,927,151,928,925,934